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Message-ID: <20160314122039.GA8719@gmail.com>
Date: Mon, 14 Mar 2016 13:20:39 +0100
From: Ingo Molnar <mingo@...nel.org>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: linux-kernel@...r.kernel.org,
Peter Zijlstra <a.p.zijlstra@...llo.nl>,
Thomas Gleixner <tglx@...utronix.de>,
Andrew Morton <akpm@...ux-foundation.org>,
"Paul E. McKenney" <paulmck@...ibm.com>
Subject: [GIT PULL] scheduler updates for v4.6
Linus,
Please pull the latest sched-core-for-linus git tree from:
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git sched-core-for-linus
# HEAD: f9c904b7613b8b4c85b10cd6b33ad41b2843fa9d sched/cputime: Fix steal_account_process_tick() to always return jiffies
The main changes in this cycle are:
- Make schedstats a runtime tunable (disabled by default) and optimize it via
static keys. As most distributions enable CONFIG_SCHEDSTATS=y due to its
instrumentation value, this is a nice performance enhancement. (Mel Gorman)
- Implement 'simple waitqueues' (swait): these are just pure waitqueues without
any of the more complex features of full-blown waitqueues (callbacks, wake
flags, wake keys, etc.). Simple waitqueues have less memory overhead and are
faster.
Use simple waitqueues in the RCU code (in 4 different places) and for handling
KVM vCPU wakeups.
(Peter Zijlstra, Daniel Wagner, Thomas Gleixner, Paul Gortmaker, Marcelo Tosatti)
- sched/numa enhancements (Rik van Riel)
- NOHZ performance enhancements (Rik van Riel)
- Various sched/deadline enhancements (Steven Rostedt)
- Various fixes (Peter Zijlstra)
- ... and a number of other fixes, cleanups and smaller enhancements.
Thanks,
Ingo
------------------>
Byungchul Park (2):
sched/core: Remove dead statement in __schedule()
sched/fair: Avoid using decay_load_missed() with a negative value
Chris Friesen (1):
sched/cputime: Fix steal_account_process_tick() to always return jiffies
Daniel Wagner (2):
kbuild: Add option to turn incompatible pointer check into error
rcu: Do not call rcu_nocb_gp_cleanup() while holding rnp->lock
Dongsheng Yang (1):
sched/core: Remove duplicated sched_group_set_shares() prototype
Frederic Weisbecker (1):
sched/fair: Consolidate nohz CPU load update code
Ingo Molnar (1):
Revert "kbuild: Add option to turn incompatible pointer check into error"
Luca Abeni (1):
sched/deadline: Remove dl_new from struct sched_dl_entity
Marcelo Tosatti (1):
KVM: Use simple waitqueue for vcpu->wq
Mel Gorman (1):
sched/debug: Make schedstats a runtime tunable that is disabled by default
Paul Gortmaker (1):
rcu: Use simple wait queues where possible in rcutree
Peter Zijlstra (4):
sched/cgroup: Fix cgroup entity load tracking tear-down
sched/deadline: Always calculate end of period on sched_yield()
sched/rt: Fix PI handling vs. sched_setscheduler()
sched/deadline: Remove superfluous call to switched_to_dl()
Peter Zijlstra (Intel) (1):
wait.[ch]: Introduce the simple waitqueue (swait) implementation
Prarit Bhargava (1):
sched/isolcpus: Output warning when the 'isolcpus=' kernel parameter is invalid
Rik van Riel (5):
sched/numa: Spread memory according to CPU and memory use
sched, time: Remove non-power-of-two divides from __acct_update_integrals()
acct, time: Change indentation in __acct_update_integrals()
time, acct: Drop irq save & restore from __acct_update_integrals()
sched, time: Switch VIRT_CPU_ACCOUNTING_GEN to jiffy granularity
Sebastian Andrzej Siewior (1):
sched/debug: Fix preempt_disable_ip recording for preempt_disable()
Stafford Horne (1):
sched/wait: Fix wait_event_freezable() documentation
Steven Rostedt (1):
sched/rt: Kick RT bandwidth timer immediately on start up
Steven Rostedt (Red Hat) (3):
sched/debug: Move the /sys/kernel/debug/sched_features file setup into debug.c
sched/debug: Move sched_domain_sysctl to debug.c
sched/debug: Add deadline scheduler bandwidth ratio to /proc/sched_debug
Documentation/kernel-parameters.txt | 5 +
Documentation/sysctl/kernel.txt | 8 +
arch/arm/kvm/arm.c | 8 +-
arch/arm/kvm/psci.c | 4 +-
arch/mips/kvm/mips.c | 8 +-
arch/powerpc/include/asm/kvm_host.h | 4 +-
arch/powerpc/kvm/book3s_hv.c | 23 +-
arch/s390/include/asm/kvm_host.h | 2 +-
arch/s390/kvm/interrupt.c | 4 +-
arch/x86/kvm/lapic.c | 6 +-
include/linux/ftrace.h | 12 +
include/linux/kvm_host.h | 5 +-
include/linux/latencytop.h | 3 +
include/linux/sched.h | 14 +-
include/linux/sched/sysctl.h | 4 +
include/linux/swait.h | 172 ++++++++++++++
include/linux/wait.h | 2 +-
kernel/latencytop.c | 14 +-
kernel/profile.c | 1 +
kernel/rcu/tree.c | 24 +-
kernel/rcu/tree.h | 12 +-
kernel/rcu/tree_plugin.h | 32 ++-
kernel/sched/Makefile | 2 +-
kernel/sched/core.c | 449 ++++++++----------------------------
kernel/sched/cputime.c | 53 +++--
kernel/sched/deadline.c | 60 +++--
kernel/sched/debug.c | 415 +++++++++++++++++++++++++++++----
kernel/sched/fair.c | 297 ++++++++++++++----------
kernel/sched/rt.c | 96 +++++---
kernel/sched/sched.h | 53 ++++-
kernel/sched/stats.h | 8 +-
kernel/sched/swait.c | 123 ++++++++++
kernel/softirq.c | 4 +-
kernel/sysctl.c | 13 +-
kernel/tsacct.c | 54 +++--
virt/kvm/async_pf.c | 4 +-
virt/kvm/kvm_main.c | 17 +-
37 files changed, 1300 insertions(+), 715 deletions(-)
create mode 100644 include/linux/swait.h
create mode 100644 kernel/sched/swait.c
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 9a53c929f017..76d68c5dfe28 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3528,6 +3528,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
sched_debug [KNL] Enables verbose scheduler debug messages.
+ schedstats= [KNL,X86] Enable or disable scheduled statistics.
+ Allowed values are enable and disable. This feature
+ incurs a small amount of overhead in the scheduler
+ but is useful for debugging and performance tuning.
+
skew_tick= [KNL] Offset the periodic timer tick per cpu to mitigate
xtime_lock contention on larger systems, and/or RCU lock
contention on all systems with CONFIG_MAXSMP set.
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index a93b414672a7..87119dc9bc64 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -760,6 +760,14 @@ rtsig-nr shows the number of RT signals currently queued.
==============================================================
+sched_schedstats:
+
+Enables/disables scheduler statistics. Enabling this feature
+incurs a small amount of overhead in the scheduler but is
+useful for debugging and performance tuning.
+
+==============================================================
+
sg-big-buff:
This file shows the size of the generic SCSI (sg) buffer.
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index dda1959f0dde..08e49c423c24 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -506,18 +506,18 @@ static void kvm_arm_resume_guest(struct kvm *kvm)
struct kvm_vcpu *vcpu;
kvm_for_each_vcpu(i, vcpu, kvm) {
- wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu);
+ struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
vcpu->arch.pause = false;
- wake_up_interruptible(wq);
+ swake_up(wq);
}
}
static void vcpu_sleep(struct kvm_vcpu *vcpu)
{
- wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu);
+ struct swait_queue_head *wq = kvm_arch_vcpu_wq(vcpu);
- wait_event_interruptible(*wq, ((!vcpu->arch.power_off) &&
+ swait_event_interruptible(*wq, ((!vcpu->arch.power_off) &&
(!vcpu->arch.pause)));
}
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index a9b3b905e661..c2b131527a64 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -70,7 +70,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
{
struct kvm *kvm = source_vcpu->kvm;
struct kvm_vcpu *vcpu = NULL;
- wait_queue_head_t *wq;
+ struct swait_queue_head *wq;
unsigned long cpu_id;
unsigned long context_id;
phys_addr_t target_pc;
@@ -119,7 +119,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
smp_mb(); /* Make sure the above is visible */
wq = kvm_arch_vcpu_wq(vcpu);
- wake_up_interruptible(wq);
+ swake_up(wq);
return PSCI_RET_SUCCESS;
}
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c
index 8bc3977576e6..341f6a1aa79a 100644
--- a/arch/mips/kvm/mips.c
+++ b/arch/mips/kvm/mips.c
@@ -445,8 +445,8 @@ int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu,
dvcpu->arch.wait = 0;
- if (waitqueue_active(&dvcpu->wq))
- wake_up_interruptible(&dvcpu->wq);
+ if (swait_active(&dvcpu->wq))
+ swake_up(&dvcpu->wq);
return 0;
}
@@ -1174,8 +1174,8 @@ static void kvm_mips_comparecount_func(unsigned long data)
kvm_mips_callbacks->queue_timer_int(vcpu);
vcpu->arch.wait = 0;
- if (waitqueue_active(&vcpu->wq))
- wake_up_interruptible(&vcpu->wq);
+ if (swait_active(&vcpu->wq))
+ swake_up(&vcpu->wq);
}
/* low level hrtimer wake routine */
diff --git a/arch/powerpc/include/asm/kvm_host.h b/arch/powerpc/include/asm/kvm_host.h
index 9d08d8cbed1a..c98afa538b3a 100644
--- a/arch/powerpc/include/asm/kvm_host.h
+++ b/arch/powerpc/include/asm/kvm_host.h
@@ -289,7 +289,7 @@ struct kvmppc_vcore {
struct list_head runnable_threads;
struct list_head preempt_list;
spinlock_t lock;
- wait_queue_head_t wq;
+ struct swait_queue_head wq;
spinlock_t stoltb_lock; /* protects stolen_tb and preempt_tb */
u64 stolen_tb;
u64 preempt_tb;
@@ -629,7 +629,7 @@ struct kvm_vcpu_arch {
u8 prodded;
u32 last_inst;
- wait_queue_head_t *wqp;
+ struct swait_queue_head *wqp;
struct kvmppc_vcore *vcore;
int ret;
int trap;
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index baeddb06811d..f1187bb6dd4d 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -114,11 +114,11 @@ static bool kvmppc_ipi_thread(int cpu)
static void kvmppc_fast_vcpu_kick_hv(struct kvm_vcpu *vcpu)
{
int cpu;
- wait_queue_head_t *wqp;
+ struct swait_queue_head *wqp;
wqp = kvm_arch_vcpu_wq(vcpu);
- if (waitqueue_active(wqp)) {
- wake_up_interruptible(wqp);
+ if (swait_active(wqp)) {
+ swake_up(wqp);
++vcpu->stat.halt_wakeup;
}
@@ -701,8 +701,8 @@ int kvmppc_pseries_do_hcall(struct kvm_vcpu *vcpu)
tvcpu->arch.prodded = 1;
smp_mb();
if (vcpu->arch.ceded) {
- if (waitqueue_active(&vcpu->wq)) {
- wake_up_interruptible(&vcpu->wq);
+ if (swait_active(&vcpu->wq)) {
+ swake_up(&vcpu->wq);
vcpu->stat.halt_wakeup++;
}
}
@@ -1459,7 +1459,7 @@ static struct kvmppc_vcore *kvmppc_vcore_create(struct kvm *kvm, int core)
INIT_LIST_HEAD(&vcore->runnable_threads);
spin_lock_init(&vcore->lock);
spin_lock_init(&vcore->stoltb_lock);
- init_waitqueue_head(&vcore->wq);
+ init_swait_queue_head(&vcore->wq);
vcore->preempt_tb = TB_NIL;
vcore->lpcr = kvm->arch.lpcr;
vcore->first_vcpuid = core * threads_per_subcore;
@@ -2531,10 +2531,9 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc)
{
struct kvm_vcpu *vcpu;
int do_sleep = 1;
+ DECLARE_SWAITQUEUE(wait);
- DEFINE_WAIT(wait);
-
- prepare_to_wait(&vc->wq, &wait, TASK_INTERRUPTIBLE);
+ prepare_to_swait(&vc->wq, &wait, TASK_INTERRUPTIBLE);
/*
* Check one last time for pending exceptions and ceded state after
@@ -2548,7 +2547,7 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc)
}
if (!do_sleep) {
- finish_wait(&vc->wq, &wait);
+ finish_swait(&vc->wq, &wait);
return;
}
@@ -2556,7 +2555,7 @@ static void kvmppc_vcore_blocked(struct kvmppc_vcore *vc)
trace_kvmppc_vcore_blocked(vc, 0);
spin_unlock(&vc->lock);
schedule();
- finish_wait(&vc->wq, &wait);
+ finish_swait(&vc->wq, &wait);
spin_lock(&vc->lock);
vc->vcore_state = VCORE_INACTIVE;
trace_kvmppc_vcore_blocked(vc, 1);
@@ -2612,7 +2611,7 @@ static int kvmppc_run_vcpu(struct kvm_run *kvm_run, struct kvm_vcpu *vcpu)
kvmppc_start_thread(vcpu, vc);
trace_kvm_guest_enter(vcpu);
} else if (vc->vcore_state == VCORE_SLEEPING) {
- wake_up(&vc->wq);
+ swake_up(&vc->wq);
}
}
diff --git a/arch/s390/include/asm/kvm_host.h b/arch/s390/include/asm/kvm_host.h
index 8959ebb6d2c9..b0c8ad0799c7 100644
--- a/arch/s390/include/asm/kvm_host.h
+++ b/arch/s390/include/asm/kvm_host.h
@@ -467,7 +467,7 @@ struct kvm_s390_irq_payload {
struct kvm_s390_local_interrupt {
spinlock_t lock;
struct kvm_s390_float_interrupt *float_int;
- wait_queue_head_t *wq;
+ struct swait_queue_head *wq;
atomic_t *cpuflags;
DECLARE_BITMAP(sigp_emerg_pending, KVM_MAX_VCPUS);
struct kvm_s390_irq_payload irq;
diff --git a/arch/s390/kvm/interrupt.c b/arch/s390/kvm/interrupt.c
index f88ca72c3a77..9ffc73221792 100644
--- a/arch/s390/kvm/interrupt.c
+++ b/arch/s390/kvm/interrupt.c
@@ -966,13 +966,13 @@ int kvm_s390_handle_wait(struct kvm_vcpu *vcpu)
void kvm_s390_vcpu_wakeup(struct kvm_vcpu *vcpu)
{
- if (waitqueue_active(&vcpu->wq)) {
+ if (swait_active(&vcpu->wq)) {
/*
* The vcpu gave up the cpu voluntarily, mark it as a good
* yield-candidate.
*/
vcpu->preempted = true;
- wake_up_interruptible(&vcpu->wq);
+ swake_up(&vcpu->wq);
vcpu->stat.halt_wakeup++;
}
}
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 36591faed13b..3a045f39ed81 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1195,7 +1195,7 @@ static void apic_update_lvtt(struct kvm_lapic *apic)
static void apic_timer_expired(struct kvm_lapic *apic)
{
struct kvm_vcpu *vcpu = apic->vcpu;
- wait_queue_head_t *q = &vcpu->wq;
+ struct swait_queue_head *q = &vcpu->wq;
struct kvm_timer *ktimer = &apic->lapic_timer;
if (atomic_read(&apic->lapic_timer.pending))
@@ -1204,8 +1204,8 @@ static void apic_timer_expired(struct kvm_lapic *apic)
atomic_inc(&apic->lapic_timer.pending);
kvm_set_pending_timer(vcpu);
- if (waitqueue_active(q))
- wake_up_interruptible(q);
+ if (swait_active(q))
+ swake_up(q);
if (apic_lvtt_tscdeadline(apic))
ktimer->expired_tscdeadline = ktimer->tscdeadline;
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index c2b340e23f62..6d9df3f7e334 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -713,6 +713,18 @@ static inline void __ftrace_enabled_restore(int enabled)
#define CALLER_ADDR5 ((unsigned long)ftrace_return_address(5))
#define CALLER_ADDR6 ((unsigned long)ftrace_return_address(6))
+static inline unsigned long get_lock_parent_ip(void)
+{
+ unsigned long addr = CALLER_ADDR0;
+
+ if (!in_lock_functions(addr))
+ return addr;
+ addr = CALLER_ADDR1;
+ if (!in_lock_functions(addr))
+ return addr;
+ return CALLER_ADDR2;
+}
+
#ifdef CONFIG_IRQSOFF_TRACER
extern void time_hardirqs_on(unsigned long a0, unsigned long a1);
extern void time_hardirqs_off(unsigned long a0, unsigned long a1);
diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h
index 861f690aa791..5276fe0916fc 100644
--- a/include/linux/kvm_host.h
+++ b/include/linux/kvm_host.h
@@ -25,6 +25,7 @@
#include <linux/irqflags.h>
#include <linux/context_tracking.h>
#include <linux/irqbypass.h>
+#include <linux/swait.h>
#include <asm/signal.h>
#include <linux/kvm.h>
@@ -218,7 +219,7 @@ struct kvm_vcpu {
int fpu_active;
int guest_fpu_loaded, guest_xcr0_loaded;
unsigned char fpu_counter;
- wait_queue_head_t wq;
+ struct swait_queue_head wq;
struct pid *pid;
int sigset_active;
sigset_t sigset;
@@ -782,7 +783,7 @@ static inline bool kvm_arch_has_assigned_device(struct kvm *kvm)
}
#endif
-static inline wait_queue_head_t *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu)
+static inline struct swait_queue_head *kvm_arch_vcpu_wq(struct kvm_vcpu *vcpu)
{
#ifdef __KVM_HAVE_ARCH_WQP
return vcpu->arch.wqp;
diff --git a/include/linux/latencytop.h b/include/linux/latencytop.h
index e23121f9d82a..59ccab297ae0 100644
--- a/include/linux/latencytop.h
+++ b/include/linux/latencytop.h
@@ -37,6 +37,9 @@ account_scheduler_latency(struct task_struct *task, int usecs, int inter)
void clear_all_latency_tracing(struct task_struct *p);
+extern int sysctl_latencytop(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos);
+
#else
static inline void
diff --git a/include/linux/sched.h b/include/linux/sched.h
index a10494a94cc3..838a89a78332 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -182,8 +182,6 @@ extern void update_cpu_load_nohz(int active);
static inline void update_cpu_load_nohz(int active) { }
#endif
-extern unsigned long get_parent_ip(unsigned long addr);
-
extern void dump_cpu_task(int cpu);
struct seq_file;
@@ -920,6 +918,10 @@ static inline int sched_info_on(void)
#endif
}
+#ifdef CONFIG_SCHEDSTATS
+void force_schedstat_enabled(void);
+#endif
+
enum cpu_idle_type {
CPU_IDLE,
CPU_NOT_IDLE,
@@ -1289,6 +1291,8 @@ struct sched_rt_entity {
unsigned long timeout;
unsigned long watchdog_stamp;
unsigned int time_slice;
+ unsigned short on_rq;
+ unsigned short on_list;
struct sched_rt_entity *back;
#ifdef CONFIG_RT_GROUP_SCHED
@@ -1329,10 +1333,6 @@ struct sched_dl_entity {
* task has to wait for a replenishment to be performed at the
* next firing of dl_timer.
*
- * @dl_new tells if a new instance arrived. If so we must
- * start executing it with full runtime and reset its absolute
- * deadline;
- *
* @dl_boosted tells if we are boosted due to DI. If so we are
* outside bandwidth enforcement mechanism (but only until we
* exit the critical section);
@@ -1340,7 +1340,7 @@ struct sched_dl_entity {
* @dl_yielded tells if task gave up the cpu before consuming
* all its available runtime during the last job.
*/
- int dl_throttled, dl_new, dl_boosted, dl_yielded;
+ int dl_throttled, dl_boosted, dl_yielded;
/*
* Bandwidth enforcement timer. Each -deadline task has its
diff --git a/include/linux/sched/sysctl.h b/include/linux/sched/sysctl.h
index c9e4731cf10b..4f080ab4f2cd 100644
--- a/include/linux/sched/sysctl.h
+++ b/include/linux/sched/sysctl.h
@@ -95,4 +95,8 @@ extern int sysctl_numa_balancing(struct ctl_table *table, int write,
void __user *buffer, size_t *lenp,
loff_t *ppos);
+extern int sysctl_schedstats(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp,
+ loff_t *ppos);
+
#endif /* _SCHED_SYSCTL_H */
diff --git a/include/linux/swait.h b/include/linux/swait.h
new file mode 100644
index 000000000000..c1f9c62a8a50
--- /dev/null
+++ b/include/linux/swait.h
@@ -0,0 +1,172 @@
+#ifndef _LINUX_SWAIT_H
+#define _LINUX_SWAIT_H
+
+#include <linux/list.h>
+#include <linux/stddef.h>
+#include <linux/spinlock.h>
+#include <asm/current.h>
+
+/*
+ * Simple wait queues
+ *
+ * While these are very similar to the other/complex wait queues (wait.h) the
+ * most important difference is that the simple waitqueue allows for
+ * deterministic behaviour -- IOW it has strictly bounded IRQ and lock hold
+ * times.
+ *
+ * In order to make this so, we had to drop a fair number of features of the
+ * other waitqueue code; notably:
+ *
+ * - mixing INTERRUPTIBLE and UNINTERRUPTIBLE sleeps on the same waitqueue;
+ * all wakeups are TASK_NORMAL in order to avoid O(n) lookups for the right
+ * sleeper state.
+ *
+ * - the exclusive mode; because this requires preserving the list order
+ * and this is hard.
+ *
+ * - custom wake functions; because you cannot give any guarantees about
+ * random code.
+ *
+ * As a side effect of this; the data structures are slimmer.
+ *
+ * One would recommend using this wait queue where possible.
+ */
+
+struct task_struct;
+
+struct swait_queue_head {
+ raw_spinlock_t lock;
+ struct list_head task_list;
+};
+
+struct swait_queue {
+ struct task_struct *task;
+ struct list_head task_list;
+};
+
+#define __SWAITQUEUE_INITIALIZER(name) { \
+ .task = current, \
+ .task_list = LIST_HEAD_INIT((name).task_list), \
+}
+
+#define DECLARE_SWAITQUEUE(name) \
+ struct swait_queue name = __SWAITQUEUE_INITIALIZER(name)
+
+#define __SWAIT_QUEUE_HEAD_INITIALIZER(name) { \
+ .lock = __RAW_SPIN_LOCK_UNLOCKED(name.lock), \
+ .task_list = LIST_HEAD_INIT((name).task_list), \
+}
+
+#define DECLARE_SWAIT_QUEUE_HEAD(name) \
+ struct swait_queue_head name = __SWAIT_QUEUE_HEAD_INITIALIZER(name)
+
+extern void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
+ struct lock_class_key *key);
+
+#define init_swait_queue_head(q) \
+ do { \
+ static struct lock_class_key __key; \
+ __init_swait_queue_head((q), #q, &__key); \
+ } while (0)
+
+#ifdef CONFIG_LOCKDEP
+# define __SWAIT_QUEUE_HEAD_INIT_ONSTACK(name) \
+ ({ init_swait_queue_head(&name); name; })
+# define DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(name) \
+ struct swait_queue_head name = __SWAIT_QUEUE_HEAD_INIT_ONSTACK(name)
+#else
+# define DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(name) \
+ DECLARE_SWAIT_QUEUE_HEAD(name)
+#endif
+
+static inline int swait_active(struct swait_queue_head *q)
+{
+ return !list_empty(&q->task_list);
+}
+
+extern void swake_up(struct swait_queue_head *q);
+extern void swake_up_all(struct swait_queue_head *q);
+extern void swake_up_locked(struct swait_queue_head *q);
+
+extern void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait);
+extern void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state);
+extern long prepare_to_swait_event(struct swait_queue_head *q, struct swait_queue *wait, int state);
+
+extern void __finish_swait(struct swait_queue_head *q, struct swait_queue *wait);
+extern void finish_swait(struct swait_queue_head *q, struct swait_queue *wait);
+
+/* as per ___wait_event() but for swait, therefore "exclusive == 0" */
+#define ___swait_event(wq, condition, state, ret, cmd) \
+({ \
+ struct swait_queue __wait; \
+ long __ret = ret; \
+ \
+ INIT_LIST_HEAD(&__wait.task_list); \
+ for (;;) { \
+ long __int = prepare_to_swait_event(&wq, &__wait, state);\
+ \
+ if (condition) \
+ break; \
+ \
+ if (___wait_is_interruptible(state) && __int) { \
+ __ret = __int; \
+ break; \
+ } \
+ \
+ cmd; \
+ } \
+ finish_swait(&wq, &__wait); \
+ __ret; \
+})
+
+#define __swait_event(wq, condition) \
+ (void)___swait_event(wq, condition, TASK_UNINTERRUPTIBLE, 0, \
+ schedule())
+
+#define swait_event(wq, condition) \
+do { \
+ if (condition) \
+ break; \
+ __swait_event(wq, condition); \
+} while (0)
+
+#define __swait_event_timeout(wq, condition, timeout) \
+ ___swait_event(wq, ___wait_cond_timeout(condition), \
+ TASK_UNINTERRUPTIBLE, timeout, \
+ __ret = schedule_timeout(__ret))
+
+#define swait_event_timeout(wq, condition, timeout) \
+({ \
+ long __ret = timeout; \
+ if (!___wait_cond_timeout(condition)) \
+ __ret = __swait_event_timeout(wq, condition, timeout); \
+ __ret; \
+})
+
+#define __swait_event_interruptible(wq, condition) \
+ ___swait_event(wq, condition, TASK_INTERRUPTIBLE, 0, \
+ schedule())
+
+#define swait_event_interruptible(wq, condition) \
+({ \
+ int __ret = 0; \
+ if (!(condition)) \
+ __ret = __swait_event_interruptible(wq, condition); \
+ __ret; \
+})
+
+#define __swait_event_interruptible_timeout(wq, condition, timeout) \
+ ___swait_event(wq, ___wait_cond_timeout(condition), \
+ TASK_INTERRUPTIBLE, timeout, \
+ __ret = schedule_timeout(__ret))
+
+#define swait_event_interruptible_timeout(wq, condition, timeout) \
+({ \
+ long __ret = timeout; \
+ if (!___wait_cond_timeout(condition)) \
+ __ret = __swait_event_interruptible_timeout(wq, \
+ condition, timeout); \
+ __ret; \
+})
+
+#endif /* _LINUX_SWAIT_H */
diff --git a/include/linux/wait.h b/include/linux/wait.h
index ae71a769b89e..27d7a0ab5da3 100644
--- a/include/linux/wait.h
+++ b/include/linux/wait.h
@@ -338,7 +338,7 @@ do { \
schedule(); try_to_freeze())
/**
- * wait_event - sleep (or freeze) until a condition gets true
+ * wait_event_freezable - sleep (or freeze) until a condition gets true
* @wq: the waitqueue to wait on
* @condition: a C expression for the event to wait for
*
diff --git a/kernel/latencytop.c b/kernel/latencytop.c
index a02812743a7e..b5c30d9f46c5 100644
--- a/kernel/latencytop.c
+++ b/kernel/latencytop.c
@@ -47,12 +47,12 @@
* of times)
*/
-#include <linux/latencytop.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/notifier.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
+#include <linux/latencytop.h>
#include <linux/export.h>
#include <linux/sched.h>
#include <linux/list.h>
@@ -289,4 +289,16 @@ static int __init init_lstats_procfs(void)
proc_create("latency_stats", 0644, NULL, &lstats_fops);
return 0;
}
+
+int sysctl_latencytop(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ int err;
+
+ err = proc_dointvec(table, write, buffer, lenp, ppos);
+ if (latencytop_enabled)
+ force_schedstat_enabled();
+
+ return err;
+}
device_initcall(init_lstats_procfs);
diff --git a/kernel/profile.c b/kernel/profile.c
index 99513e1160e5..51369697466e 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -59,6 +59,7 @@ int profile_setup(char *str)
if (!strncmp(str, sleepstr, strlen(sleepstr))) {
#ifdef CONFIG_SCHEDSTATS
+ force_schedstat_enabled();
prof_on = SLEEP_PROFILING;
if (str[strlen(sleepstr)] == ',')
str += strlen(sleepstr) + 1;
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index e41dd4131f7a..9fd5b628a88d 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1614,7 +1614,6 @@ static int rcu_future_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp)
int needmore;
struct rcu_data *rdp = this_cpu_ptr(rsp->rda);
- rcu_nocb_gp_cleanup(rsp, rnp);
rnp->need_future_gp[c & 0x1] = 0;
needmore = rnp->need_future_gp[(c + 1) & 0x1];
trace_rcu_future_gp(rnp, rdp, c,
@@ -1635,7 +1634,7 @@ static void rcu_gp_kthread_wake(struct rcu_state *rsp)
!READ_ONCE(rsp->gp_flags) ||
!rsp->gp_kthread)
return;
- wake_up(&rsp->gp_wq);
+ swake_up(&rsp->gp_wq);
}
/*
@@ -2010,6 +2009,7 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
int nocb = 0;
struct rcu_data *rdp;
struct rcu_node *rnp = rcu_get_root(rsp);
+ struct swait_queue_head *sq;
WRITE_ONCE(rsp->gp_activity, jiffies);
raw_spin_lock_irq_rcu_node(rnp);
@@ -2046,7 +2046,9 @@ static void rcu_gp_cleanup(struct rcu_state *rsp)
needgp = __note_gp_changes(rsp, rnp, rdp) || needgp;
/* smp_mb() provided by prior unlock-lock pair. */
nocb += rcu_future_gp_cleanup(rsp, rnp);
+ sq = rcu_nocb_gp_get(rnp);
raw_spin_unlock_irq(&rnp->lock);
+ rcu_nocb_gp_cleanup(sq);
cond_resched_rcu_qs();
WRITE_ONCE(rsp->gp_activity, jiffies);
rcu_gp_slow(rsp, gp_cleanup_delay);
@@ -2092,7 +2094,7 @@ static int __noreturn rcu_gp_kthread(void *arg)
READ_ONCE(rsp->gpnum),
TPS("reqwait"));
rsp->gp_state = RCU_GP_WAIT_GPS;
- wait_event_interruptible(rsp->gp_wq,
+ swait_event_interruptible(rsp->gp_wq,
READ_ONCE(rsp->gp_flags) &
RCU_GP_FLAG_INIT);
rsp->gp_state = RCU_GP_DONE_GPS;
@@ -2122,7 +2124,7 @@ static int __noreturn rcu_gp_kthread(void *arg)
READ_ONCE(rsp->gpnum),
TPS("fqswait"));
rsp->gp_state = RCU_GP_WAIT_FQS;
- ret = wait_event_interruptible_timeout(rsp->gp_wq,
+ ret = swait_event_interruptible_timeout(rsp->gp_wq,
rcu_gp_fqs_check_wake(rsp, &gf), j);
rsp->gp_state = RCU_GP_DOING_FQS;
/* Locking provides needed memory barriers. */
@@ -2246,7 +2248,7 @@ static void rcu_report_qs_rsp(struct rcu_state *rsp, unsigned long flags)
WARN_ON_ONCE(!rcu_gp_in_progress(rsp));
WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
raw_spin_unlock_irqrestore(&rcu_get_root(rsp)->lock, flags);
- rcu_gp_kthread_wake(rsp);
+ swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */
}
/*
@@ -2900,7 +2902,7 @@ static void force_quiescent_state(struct rcu_state *rsp)
}
WRITE_ONCE(rsp->gp_flags, READ_ONCE(rsp->gp_flags) | RCU_GP_FLAG_FQS);
raw_spin_unlock_irqrestore(&rnp_old->lock, flags);
- rcu_gp_kthread_wake(rsp);
+ swake_up(&rsp->gp_wq); /* Memory barrier implied by swake_up() path. */
}
/*
@@ -3529,7 +3531,7 @@ static void __rcu_report_exp_rnp(struct rcu_state *rsp, struct rcu_node *rnp,
raw_spin_unlock_irqrestore(&rnp->lock, flags);
if (wake) {
smp_mb(); /* EGP done before wake_up(). */
- wake_up(&rsp->expedited_wq);
+ swake_up(&rsp->expedited_wq);
}
break;
}
@@ -3780,7 +3782,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
jiffies_start = jiffies;
for (;;) {
- ret = wait_event_interruptible_timeout(
+ ret = swait_event_timeout(
rsp->expedited_wq,
sync_rcu_preempt_exp_done(rnp_root),
jiffies_stall);
@@ -3788,7 +3790,7 @@ static void synchronize_sched_expedited_wait(struct rcu_state *rsp)
return;
if (ret < 0) {
/* Hit a signal, disable CPU stall warnings. */
- wait_event(rsp->expedited_wq,
+ swait_event(rsp->expedited_wq,
sync_rcu_preempt_exp_done(rnp_root));
return;
}
@@ -4482,8 +4484,8 @@ static void __init rcu_init_one(struct rcu_state *rsp)
}
}
- init_waitqueue_head(&rsp->gp_wq);
- init_waitqueue_head(&rsp->expedited_wq);
+ init_swait_queue_head(&rsp->gp_wq);
+ init_swait_queue_head(&rsp->expedited_wq);
rnp = rsp->level[rcu_num_lvls - 1];
for_each_possible_cpu(i) {
while (i > rnp->grphi)
diff --git a/kernel/rcu/tree.h b/kernel/rcu/tree.h
index 83360b4f4352..bbd235d0e71f 100644
--- a/kernel/rcu/tree.h
+++ b/kernel/rcu/tree.h
@@ -27,6 +27,7 @@
#include <linux/threads.h>
#include <linux/cpumask.h>
#include <linux/seqlock.h>
+#include <linux/swait.h>
#include <linux/stop_machine.h>
/*
@@ -243,7 +244,7 @@ struct rcu_node {
/* Refused to boost: not sure why, though. */
/* This can happen due to race conditions. */
#ifdef CONFIG_RCU_NOCB_CPU
- wait_queue_head_t nocb_gp_wq[2];
+ struct swait_queue_head nocb_gp_wq[2];
/* Place for rcu_nocb_kthread() to wait GP. */
#endif /* #ifdef CONFIG_RCU_NOCB_CPU */
int need_future_gp[2];
@@ -399,7 +400,7 @@ struct rcu_data {
atomic_long_t nocb_q_count_lazy; /* invocation (all stages). */
struct rcu_head *nocb_follower_head; /* CBs ready to invoke. */
struct rcu_head **nocb_follower_tail;
- wait_queue_head_t nocb_wq; /* For nocb kthreads to sleep on. */
+ struct swait_queue_head nocb_wq; /* For nocb kthreads to sleep on. */
struct task_struct *nocb_kthread;
int nocb_defer_wakeup; /* Defer wakeup of nocb_kthread. */
@@ -478,7 +479,7 @@ struct rcu_state {
unsigned long gpnum; /* Current gp number. */
unsigned long completed; /* # of last completed gp. */
struct task_struct *gp_kthread; /* Task for grace periods. */
- wait_queue_head_t gp_wq; /* Where GP task waits. */
+ struct swait_queue_head gp_wq; /* Where GP task waits. */
short gp_flags; /* Commands for GP task. */
short gp_state; /* GP kthread sleep state. */
@@ -506,7 +507,7 @@ struct rcu_state {
unsigned long expedited_sequence; /* Take a ticket. */
atomic_long_t expedited_normal; /* # fallbacks to normal. */
atomic_t expedited_need_qs; /* # CPUs left to check in. */
- wait_queue_head_t expedited_wq; /* Wait for check-ins. */
+ struct swait_queue_head expedited_wq; /* Wait for check-ins. */
int ncpus_snap; /* # CPUs seen last time. */
unsigned long jiffies_force_qs; /* Time at which to invoke */
@@ -621,7 +622,8 @@ static void zero_cpu_stall_ticks(struct rcu_data *rdp);
static void increment_cpu_stall_ticks(void);
static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu);
static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq);
-static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp);
+static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp);
+static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq);
static void rcu_init_one_nocb(struct rcu_node *rnp);
static bool __call_rcu_nocb(struct rcu_data *rdp, struct rcu_head *rhp,
bool lazy, unsigned long flags);
diff --git a/kernel/rcu/tree_plugin.h b/kernel/rcu/tree_plugin.h
index 9467a8b7e756..080bd202d360 100644
--- a/kernel/rcu/tree_plugin.h
+++ b/kernel/rcu/tree_plugin.h
@@ -1811,9 +1811,9 @@ early_param("rcu_nocb_poll", parse_rcu_nocb_poll);
* Wake up any no-CBs CPUs' kthreads that were waiting on the just-ended
* grace period.
*/
-static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp)
+static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq)
{
- wake_up_all(&rnp->nocb_gp_wq[rnp->completed & 0x1]);
+ swake_up_all(sq);
}
/*
@@ -1829,10 +1829,15 @@ static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq)
rnp->need_future_gp[(rnp->completed + 1) & 0x1] += nrq;
}
+static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp)
+{
+ return &rnp->nocb_gp_wq[rnp->completed & 0x1];
+}
+
static void rcu_init_one_nocb(struct rcu_node *rnp)
{
- init_waitqueue_head(&rnp->nocb_gp_wq[0]);
- init_waitqueue_head(&rnp->nocb_gp_wq[1]);
+ init_swait_queue_head(&rnp->nocb_gp_wq[0]);
+ init_swait_queue_head(&rnp->nocb_gp_wq[1]);
}
#ifndef CONFIG_RCU_NOCB_CPU_ALL
@@ -1857,7 +1862,7 @@ static void wake_nocb_leader(struct rcu_data *rdp, bool force)
if (READ_ONCE(rdp_leader->nocb_leader_sleep) || force) {
/* Prior smp_mb__after_atomic() orders against prior enqueue. */
WRITE_ONCE(rdp_leader->nocb_leader_sleep, false);
- wake_up(&rdp_leader->nocb_wq);
+ swake_up(&rdp_leader->nocb_wq);
}
}
@@ -2069,7 +2074,7 @@ static void rcu_nocb_wait_gp(struct rcu_data *rdp)
*/
trace_rcu_future_gp(rnp, rdp, c, TPS("StartWait"));
for (;;) {
- wait_event_interruptible(
+ swait_event_interruptible(
rnp->nocb_gp_wq[c & 0x1],
(d = ULONG_CMP_GE(READ_ONCE(rnp->completed), c)));
if (likely(d))
@@ -2097,7 +2102,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
/* Wait for callbacks to appear. */
if (!rcu_nocb_poll) {
trace_rcu_nocb_wake(my_rdp->rsp->name, my_rdp->cpu, "Sleep");
- wait_event_interruptible(my_rdp->nocb_wq,
+ swait_event_interruptible(my_rdp->nocb_wq,
!READ_ONCE(my_rdp->nocb_leader_sleep));
/* Memory barrier handled by smp_mb() calls below and repoll. */
} else if (firsttime) {
@@ -2172,7 +2177,7 @@ static void nocb_leader_wait(struct rcu_data *my_rdp)
* List was empty, wake up the follower.
* Memory barriers supplied by atomic_long_add().
*/
- wake_up(&rdp->nocb_wq);
+ swake_up(&rdp->nocb_wq);
}
}
@@ -2193,7 +2198,7 @@ static void nocb_follower_wait(struct rcu_data *rdp)
if (!rcu_nocb_poll) {
trace_rcu_nocb_wake(rdp->rsp->name, rdp->cpu,
"FollowerSleep");
- wait_event_interruptible(rdp->nocb_wq,
+ swait_event_interruptible(rdp->nocb_wq,
READ_ONCE(rdp->nocb_follower_head));
} else if (firsttime) {
/* Don't drown trace log with "Poll"! */
@@ -2352,7 +2357,7 @@ void __init rcu_init_nohz(void)
static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)
{
rdp->nocb_tail = &rdp->nocb_head;
- init_waitqueue_head(&rdp->nocb_wq);
+ init_swait_queue_head(&rdp->nocb_wq);
rdp->nocb_follower_tail = &rdp->nocb_follower_head;
}
@@ -2502,7 +2507,7 @@ static bool rcu_nocb_cpu_needs_barrier(struct rcu_state *rsp, int cpu)
return false;
}
-static void rcu_nocb_gp_cleanup(struct rcu_state *rsp, struct rcu_node *rnp)
+static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq)
{
}
@@ -2510,6 +2515,11 @@ static void rcu_nocb_gp_set(struct rcu_node *rnp, int nrq)
{
}
+static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp)
+{
+ return NULL;
+}
+
static void rcu_init_one_nocb(struct rcu_node *rnp)
{
}
diff --git a/kernel/sched/Makefile b/kernel/sched/Makefile
index 67687973ce80..7d4cba227cbd 100644
--- a/kernel/sched/Makefile
+++ b/kernel/sched/Makefile
@@ -13,7 +13,7 @@ endif
obj-y += core.o loadavg.o clock.o cputime.o
obj-y += idle_task.o fair.o rt.o deadline.o stop_task.o
-obj-y += wait.o completion.o idle.o
+obj-y += wait.o swait.o completion.o idle.o
obj-$(CONFIG_SMP) += cpupri.o cpudeadline.o
obj-$(CONFIG_SCHED_AUTOGROUP) += auto_group.o
obj-$(CONFIG_SCHEDSTATS) += stats.o
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9503d590e5ef..249e37dc02c8 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -66,12 +66,10 @@
#include <linux/pagemap.h>
#include <linux/hrtimer.h>
#include <linux/tick.h>
-#include <linux/debugfs.h>
#include <linux/ctype.h>
#include <linux/ftrace.h>
#include <linux/slab.h>
#include <linux/init_task.h>
-#include <linux/binfmts.h>
#include <linux/context_tracking.h>
#include <linux/compiler.h>
@@ -124,138 +122,6 @@ const_debug unsigned int sysctl_sched_features =
#undef SCHED_FEAT
-#ifdef CONFIG_SCHED_DEBUG
-#define SCHED_FEAT(name, enabled) \
- #name ,
-
-static const char * const sched_feat_names[] = {
-#include "features.h"
-};
-
-#undef SCHED_FEAT
-
-static int sched_feat_show(struct seq_file *m, void *v)
-{
- int i;
-
- for (i = 0; i < __SCHED_FEAT_NR; i++) {
- if (!(sysctl_sched_features & (1UL << i)))
- seq_puts(m, "NO_");
- seq_printf(m, "%s ", sched_feat_names[i]);
- }
- seq_puts(m, "\n");
-
- return 0;
-}
-
-#ifdef HAVE_JUMP_LABEL
-
-#define jump_label_key__true STATIC_KEY_INIT_TRUE
-#define jump_label_key__false STATIC_KEY_INIT_FALSE
-
-#define SCHED_FEAT(name, enabled) \
- jump_label_key__##enabled ,
-
-struct static_key sched_feat_keys[__SCHED_FEAT_NR] = {
-#include "features.h"
-};
-
-#undef SCHED_FEAT
-
-static void sched_feat_disable(int i)
-{
- static_key_disable(&sched_feat_keys[i]);
-}
-
-static void sched_feat_enable(int i)
-{
- static_key_enable(&sched_feat_keys[i]);
-}
-#else
-static void sched_feat_disable(int i) { };
-static void sched_feat_enable(int i) { };
-#endif /* HAVE_JUMP_LABEL */
-
-static int sched_feat_set(char *cmp)
-{
- int i;
- int neg = 0;
-
- if (strncmp(cmp, "NO_", 3) == 0) {
- neg = 1;
- cmp += 3;
- }
-
- for (i = 0; i < __SCHED_FEAT_NR; i++) {
- if (strcmp(cmp, sched_feat_names[i]) == 0) {
- if (neg) {
- sysctl_sched_features &= ~(1UL << i);
- sched_feat_disable(i);
- } else {
- sysctl_sched_features |= (1UL << i);
- sched_feat_enable(i);
- }
- break;
- }
- }
-
- return i;
-}
-
-static ssize_t
-sched_feat_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
-{
- char buf[64];
- char *cmp;
- int i;
- struct inode *inode;
-
- if (cnt > 63)
- cnt = 63;
-
- if (copy_from_user(&buf, ubuf, cnt))
- return -EFAULT;
-
- buf[cnt] = 0;
- cmp = strstrip(buf);
-
- /* Ensure the static_key remains in a consistent state */
- inode = file_inode(filp);
- inode_lock(inode);
- i = sched_feat_set(cmp);
- inode_unlock(inode);
- if (i == __SCHED_FEAT_NR)
- return -EINVAL;
-
- *ppos += cnt;
-
- return cnt;
-}
-
-static int sched_feat_open(struct inode *inode, struct file *filp)
-{
- return single_open(filp, sched_feat_show, NULL);
-}
-
-static const struct file_operations sched_feat_fops = {
- .open = sched_feat_open,
- .write = sched_feat_write,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static __init int sched_init_debug(void)
-{
- debugfs_create_file("sched_features", 0644, NULL, NULL,
- &sched_feat_fops);
-
- return 0;
-}
-late_initcall(sched_init_debug);
-#endif /* CONFIG_SCHED_DEBUG */
-
/*
* Number of tasks to iterate in a single balance run.
* Limited because this is done with IRQs disabled.
@@ -2093,7 +1959,8 @@ try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
ttwu_queue(p, cpu);
stat:
- ttwu_stat(p, cpu, wake_flags);
+ if (schedstat_enabled())
+ ttwu_stat(p, cpu, wake_flags);
out:
raw_spin_unlock_irqrestore(&p->pi_lock, flags);
@@ -2141,7 +2008,8 @@ static void try_to_wake_up_local(struct task_struct *p)
ttwu_activate(rq, p, ENQUEUE_WAKEUP);
ttwu_do_wakeup(rq, p, 0);
- ttwu_stat(p, smp_processor_id(), 0);
+ if (schedstat_enabled())
+ ttwu_stat(p, smp_processor_id(), 0);
out:
raw_spin_unlock(&p->pi_lock);
}
@@ -2183,7 +2051,6 @@ void __dl_clear_params(struct task_struct *p)
dl_se->dl_bw = 0;
dl_se->dl_throttled = 0;
- dl_se->dl_new = 1;
dl_se->dl_yielded = 0;
}
@@ -2210,6 +2077,7 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
#endif
#ifdef CONFIG_SCHEDSTATS
+ /* Even if schedstat is disabled, there should not be garbage */
memset(&p->se.statistics, 0, sizeof(p->se.statistics));
#endif
@@ -2218,6 +2086,10 @@ static void __sched_fork(unsigned long clone_flags, struct task_struct *p)
__dl_clear_params(p);
INIT_LIST_HEAD(&p->rt.run_list);
+ p->rt.timeout = 0;
+ p->rt.time_slice = sched_rr_timeslice;
+ p->rt.on_rq = 0;
+ p->rt.on_list = 0;
#ifdef CONFIG_PREEMPT_NOTIFIERS
INIT_HLIST_HEAD(&p->preempt_notifiers);
@@ -2281,6 +2153,69 @@ int sysctl_numa_balancing(struct ctl_table *table, int write,
#endif
#endif
+DEFINE_STATIC_KEY_FALSE(sched_schedstats);
+
+#ifdef CONFIG_SCHEDSTATS
+static void set_schedstats(bool enabled)
+{
+ if (enabled)
+ static_branch_enable(&sched_schedstats);
+ else
+ static_branch_disable(&sched_schedstats);
+}
+
+void force_schedstat_enabled(void)
+{
+ if (!schedstat_enabled()) {
+ pr_info("kernel profiling enabled schedstats, disable via kernel.sched_schedstats.\n");
+ static_branch_enable(&sched_schedstats);
+ }
+}
+
+static int __init setup_schedstats(char *str)
+{
+ int ret = 0;
+ if (!str)
+ goto out;
+
+ if (!strcmp(str, "enable")) {
+ set_schedstats(true);
+ ret = 1;
+ } else if (!strcmp(str, "disable")) {
+ set_schedstats(false);
+ ret = 1;
+ }
+out:
+ if (!ret)
+ pr_warn("Unable to parse schedstats=\n");
+
+ return ret;
+}
+__setup("schedstats=", setup_schedstats);
+
+#ifdef CONFIG_PROC_SYSCTL
+int sysctl_schedstats(struct ctl_table *table, int write,
+ void __user *buffer, size_t *lenp, loff_t *ppos)
+{
+ struct ctl_table t;
+ int err;
+ int state = static_branch_likely(&sched_schedstats);
+
+ if (write && !capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ t = *table;
+ t.data = &state;
+ err = proc_dointvec_minmax(&t, write, buffer, lenp, ppos);
+ if (err < 0)
+ return err;
+ if (write)
+ set_schedstats(state);
+ return err;
+}
+#endif
+#endif
+
/*
* fork()/clone()-time setup:
*/
@@ -3010,16 +2945,6 @@ u64 scheduler_tick_max_deferment(void)
}
#endif
-notrace unsigned long get_parent_ip(unsigned long addr)
-{
- if (in_lock_functions(addr)) {
- addr = CALLER_ADDR2;
- if (in_lock_functions(addr))
- addr = CALLER_ADDR3;
- }
- return addr;
-}
-
#if defined(CONFIG_PREEMPT) && (defined(CONFIG_DEBUG_PREEMPT) || \
defined(CONFIG_PREEMPT_TRACER))
@@ -3041,7 +2966,7 @@ void preempt_count_add(int val)
PREEMPT_MASK - 10);
#endif
if (preempt_count() == val) {
- unsigned long ip = get_parent_ip(CALLER_ADDR1);
+ unsigned long ip = get_lock_parent_ip();
#ifdef CONFIG_DEBUG_PREEMPT
current->preempt_disable_ip = ip;
#endif
@@ -3068,7 +2993,7 @@ void preempt_count_sub(int val)
#endif
if (preempt_count() == val)
- trace_preempt_on(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
__preempt_count_sub(val);
}
EXPORT_SYMBOL(preempt_count_sub);
@@ -3280,7 +3205,6 @@ static void __sched notrace __schedule(bool preempt)
trace_sched_switch(preempt, prev, next);
rq = context_switch(rq, prev, next); /* unlocks the rq */
- cpu = cpu_of(rq);
} else {
lockdep_unpin_lock(&rq->lock);
raw_spin_unlock_irq(&rq->lock);
@@ -3466,7 +3390,7 @@ EXPORT_SYMBOL(default_wake_function);
*/
void rt_mutex_setprio(struct task_struct *p, int prio)
{
- int oldprio, queued, running, enqueue_flag = ENQUEUE_RESTORE;
+ int oldprio, queued, running, queue_flag = DEQUEUE_SAVE | DEQUEUE_MOVE;
struct rq *rq;
const struct sched_class *prev_class;
@@ -3494,11 +3418,15 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
trace_sched_pi_setprio(p, prio);
oldprio = p->prio;
+
+ if (oldprio == prio)
+ queue_flag &= ~DEQUEUE_MOVE;
+
prev_class = p->sched_class;
queued = task_on_rq_queued(p);
running = task_current(rq, p);
if (queued)
- dequeue_task(rq, p, DEQUEUE_SAVE);
+ dequeue_task(rq, p, queue_flag);
if (running)
put_prev_task(rq, p);
@@ -3516,7 +3444,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (!dl_prio(p->normal_prio) ||
(pi_task && dl_entity_preempt(&pi_task->dl, &p->dl))) {
p->dl.dl_boosted = 1;
- enqueue_flag |= ENQUEUE_REPLENISH;
+ queue_flag |= ENQUEUE_REPLENISH;
} else
p->dl.dl_boosted = 0;
p->sched_class = &dl_sched_class;
@@ -3524,7 +3452,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (dl_prio(oldprio))
p->dl.dl_boosted = 0;
if (oldprio < prio)
- enqueue_flag |= ENQUEUE_HEAD;
+ queue_flag |= ENQUEUE_HEAD;
p->sched_class = &rt_sched_class;
} else {
if (dl_prio(oldprio))
@@ -3539,7 +3467,7 @@ void rt_mutex_setprio(struct task_struct *p, int prio)
if (running)
p->sched_class->set_curr_task(rq);
if (queued)
- enqueue_task(rq, p, enqueue_flag);
+ enqueue_task(rq, p, queue_flag);
check_class_changed(rq, p, prev_class, oldprio);
out_unlock:
@@ -3895,6 +3823,7 @@ static int __sched_setscheduler(struct task_struct *p,
const struct sched_class *prev_class;
struct rq *rq;
int reset_on_fork;
+ int queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE;
/* may grab non-irq protected spin_locks */
BUG_ON(in_interrupt());
@@ -4077,17 +4006,14 @@ static int __sched_setscheduler(struct task_struct *p,
* itself.
*/
new_effective_prio = rt_mutex_get_effective_prio(p, newprio);
- if (new_effective_prio == oldprio) {
- __setscheduler_params(p, attr);
- task_rq_unlock(rq, p, &flags);
- return 0;
- }
+ if (new_effective_prio == oldprio)
+ queue_flags &= ~DEQUEUE_MOVE;
}
queued = task_on_rq_queued(p);
running = task_current(rq, p);
if (queued)
- dequeue_task(rq, p, DEQUEUE_SAVE);
+ dequeue_task(rq, p, queue_flags);
if (running)
put_prev_task(rq, p);
@@ -4097,15 +4023,14 @@ static int __sched_setscheduler(struct task_struct *p,
if (running)
p->sched_class->set_curr_task(rq);
if (queued) {
- int enqueue_flags = ENQUEUE_RESTORE;
/*
* We enqueue to tail when the priority of a task is
* increased (user space view).
*/
- if (oldprio <= p->prio)
- enqueue_flags |= ENQUEUE_HEAD;
+ if (oldprio < p->prio)
+ queue_flags |= ENQUEUE_HEAD;
- enqueue_task(rq, p, enqueue_flags);
+ enqueue_task(rq, p, queue_flags);
}
check_class_changed(rq, p, prev_class, oldprio);
@@ -5405,183 +5330,6 @@ static void migrate_tasks(struct rq *dead_rq)
}
#endif /* CONFIG_HOTPLUG_CPU */
-#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
-
-static struct ctl_table sd_ctl_dir[] = {
- {
- .procname = "sched_domain",
- .mode = 0555,
- },
- {}
-};
-
-static struct ctl_table sd_ctl_root[] = {
- {
- .procname = "kernel",
- .mode = 0555,
- .child = sd_ctl_dir,
- },
- {}
-};
-
-static struct ctl_table *sd_alloc_ctl_entry(int n)
-{
- struct ctl_table *entry =
- kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL);
-
- return entry;
-}
-
-static void sd_free_ctl_entry(struct ctl_table **tablep)
-{
- struct ctl_table *entry;
-
- /*
- * In the intermediate directories, both the child directory and
- * procname are dynamically allocated and could fail but the mode
- * will always be set. In the lowest directory the names are
- * static strings and all have proc handlers.
- */
- for (entry = *tablep; entry->mode; entry++) {
- if (entry->child)
- sd_free_ctl_entry(&entry->child);
- if (entry->proc_handler == NULL)
- kfree(entry->procname);
- }
-
- kfree(*tablep);
- *tablep = NULL;
-}
-
-static int min_load_idx = 0;
-static int max_load_idx = CPU_LOAD_IDX_MAX-1;
-
-static void
-set_table_entry(struct ctl_table *entry,
- const char *procname, void *data, int maxlen,
- umode_t mode, proc_handler *proc_handler,
- bool load_idx)
-{
- entry->procname = procname;
- entry->data = data;
- entry->maxlen = maxlen;
- entry->mode = mode;
- entry->proc_handler = proc_handler;
-
- if (load_idx) {
- entry->extra1 = &min_load_idx;
- entry->extra2 = &max_load_idx;
- }
-}
-
-static struct ctl_table *
-sd_alloc_ctl_domain_table(struct sched_domain *sd)
-{
- struct ctl_table *table = sd_alloc_ctl_entry(14);
-
- if (table == NULL)
- return NULL;
-
- set_table_entry(&table[0], "min_interval", &sd->min_interval,
- sizeof(long), 0644, proc_doulongvec_minmax, false);
- set_table_entry(&table[1], "max_interval", &sd->max_interval,
- sizeof(long), 0644, proc_doulongvec_minmax, false);
- set_table_entry(&table[2], "busy_idx", &sd->busy_idx,
- sizeof(int), 0644, proc_dointvec_minmax, true);
- set_table_entry(&table[3], "idle_idx", &sd->idle_idx,
- sizeof(int), 0644, proc_dointvec_minmax, true);
- set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,
- sizeof(int), 0644, proc_dointvec_minmax, true);
- set_table_entry(&table[5], "wake_idx", &sd->wake_idx,
- sizeof(int), 0644, proc_dointvec_minmax, true);
- set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,
- sizeof(int), 0644, proc_dointvec_minmax, true);
- set_table_entry(&table[7], "busy_factor", &sd->busy_factor,
- sizeof(int), 0644, proc_dointvec_minmax, false);
- set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,
- sizeof(int), 0644, proc_dointvec_minmax, false);
- set_table_entry(&table[9], "cache_nice_tries",
- &sd->cache_nice_tries,
- sizeof(int), 0644, proc_dointvec_minmax, false);
- set_table_entry(&table[10], "flags", &sd->flags,
- sizeof(int), 0644, proc_dointvec_minmax, false);
- set_table_entry(&table[11], "max_newidle_lb_cost",
- &sd->max_newidle_lb_cost,
- sizeof(long), 0644, proc_doulongvec_minmax, false);
- set_table_entry(&table[12], "name", sd->name,
- CORENAME_MAX_SIZE, 0444, proc_dostring, false);
- /* &table[13] is terminator */
-
- return table;
-}
-
-static struct ctl_table *sd_alloc_ctl_cpu_table(int cpu)
-{
- struct ctl_table *entry, *table;
- struct sched_domain *sd;
- int domain_num = 0, i;
- char buf[32];
-
- for_each_domain(cpu, sd)
- domain_num++;
- entry = table = sd_alloc_ctl_entry(domain_num + 1);
- if (table == NULL)
- return NULL;
-
- i = 0;
- for_each_domain(cpu, sd) {
- snprintf(buf, 32, "domain%d", i);
- entry->procname = kstrdup(buf, GFP_KERNEL);
- entry->mode = 0555;
- entry->child = sd_alloc_ctl_domain_table(sd);
- entry++;
- i++;
- }
- return table;
-}
-
-static struct ctl_table_header *sd_sysctl_header;
-static void register_sched_domain_sysctl(void)
-{
- int i, cpu_num = num_possible_cpus();
- struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
- char buf[32];
-
- WARN_ON(sd_ctl_dir[0].child);
- sd_ctl_dir[0].child = entry;
-
- if (entry == NULL)
- return;
-
- for_each_possible_cpu(i) {
- snprintf(buf, 32, "cpu%d", i);
- entry->procname = kstrdup(buf, GFP_KERNEL);
- entry->mode = 0555;
- entry->child = sd_alloc_ctl_cpu_table(i);
- entry++;
- }
-
- WARN_ON(sd_sysctl_header);
- sd_sysctl_header = register_sysctl_table(sd_ctl_root);
-}
-
-/* may be called multiple times per register */
-static void unregister_sched_domain_sysctl(void)
-{
- unregister_sysctl_table(sd_sysctl_header);
- sd_sysctl_header = NULL;
- if (sd_ctl_dir[0].child)
- sd_free_ctl_entry(&sd_ctl_dir[0].child);
-}
-#else
-static void register_sched_domain_sysctl(void)
-{
-}
-static void unregister_sched_domain_sysctl(void)
-{
-}
-#endif /* CONFIG_SCHED_DEBUG && CONFIG_SYSCTL */
-
static void set_rq_online(struct rq *rq)
{
if (!rq->online) {
@@ -6173,11 +5921,16 @@ cpu_attach_domain(struct sched_domain *sd, struct root_domain *rd, int cpu)
/* Setup the mask of cpus configured for isolated domains */
static int __init isolated_cpu_setup(char *str)
{
+ int ret;
+
alloc_bootmem_cpumask_var(&cpu_isolated_map);
- cpulist_parse(str, cpu_isolated_map);
+ ret = cpulist_parse(str, cpu_isolated_map);
+ if (ret) {
+ pr_err("sched: Error, all isolcpus= values must be between 0 and %d\n", nr_cpu_ids);
+ return 0;
+ }
return 1;
}
-
__setup("isolcpus=", isolated_cpu_setup);
struct s_data {
@@ -7860,11 +7613,9 @@ void sched_destroy_group(struct task_group *tg)
void sched_offline_group(struct task_group *tg)
{
unsigned long flags;
- int i;
/* end participation in shares distribution */
- for_each_possible_cpu(i)
- unregister_fair_sched_group(tg, i);
+ unregister_fair_sched_group(tg);
spin_lock_irqsave(&task_group_lock, flags);
list_del_rcu(&tg->list);
@@ -7890,7 +7641,7 @@ void sched_move_task(struct task_struct *tsk)
queued = task_on_rq_queued(tsk);
if (queued)
- dequeue_task(rq, tsk, DEQUEUE_SAVE);
+ dequeue_task(rq, tsk, DEQUEUE_SAVE | DEQUEUE_MOVE);
if (unlikely(running))
put_prev_task(rq, tsk);
@@ -7914,7 +7665,7 @@ void sched_move_task(struct task_struct *tsk)
if (unlikely(running))
tsk->sched_class->set_curr_task(rq);
if (queued)
- enqueue_task(rq, tsk, ENQUEUE_RESTORE);
+ enqueue_task(rq, tsk, ENQUEUE_RESTORE | ENQUEUE_MOVE);
task_rq_unlock(rq, tsk, &flags);
}
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index b2ab2ffb1adc..75f98c5498d5 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -262,21 +262,21 @@ static __always_inline bool steal_account_process_tick(void)
#ifdef CONFIG_PARAVIRT
if (static_key_false(¶virt_steal_enabled)) {
u64 steal;
- cputime_t steal_ct;
+ unsigned long steal_jiffies;
steal = paravirt_steal_clock(smp_processor_id());
steal -= this_rq()->prev_steal_time;
/*
- * cputime_t may be less precise than nsecs (eg: if it's
- * based on jiffies). Lets cast the result to cputime
+ * steal is in nsecs but our caller is expecting steal
+ * time in jiffies. Lets cast the result to jiffies
* granularity and account the rest on the next rounds.
*/
- steal_ct = nsecs_to_cputime(steal);
- this_rq()->prev_steal_time += cputime_to_nsecs(steal_ct);
+ steal_jiffies = nsecs_to_jiffies(steal);
+ this_rq()->prev_steal_time += jiffies_to_nsecs(steal_jiffies);
- account_steal_time(steal_ct);
- return steal_ct;
+ account_steal_time(jiffies_to_cputime(steal_jiffies));
+ return steal_jiffies;
}
#endif
return false;
@@ -668,26 +668,25 @@ void thread_group_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime
#endif /* !CONFIG_VIRT_CPU_ACCOUNTING_NATIVE */
#ifdef CONFIG_VIRT_CPU_ACCOUNTING_GEN
-static unsigned long long vtime_delta(struct task_struct *tsk)
+static cputime_t vtime_delta(struct task_struct *tsk)
{
- unsigned long long clock;
+ unsigned long now = READ_ONCE(jiffies);
- clock = local_clock();
- if (clock < tsk->vtime_snap)
+ if (time_before(now, (unsigned long)tsk->vtime_snap))
return 0;
- return clock - tsk->vtime_snap;
+ return jiffies_to_cputime(now - tsk->vtime_snap);
}
static cputime_t get_vtime_delta(struct task_struct *tsk)
{
- unsigned long long delta = vtime_delta(tsk);
+ unsigned long now = READ_ONCE(jiffies);
+ unsigned long delta = now - tsk->vtime_snap;
WARN_ON_ONCE(tsk->vtime_snap_whence == VTIME_INACTIVE);
- tsk->vtime_snap += delta;
+ tsk->vtime_snap = now;
- /* CHECKME: always safe to convert nsecs to cputime? */
- return nsecs_to_cputime(delta);
+ return jiffies_to_cputime(delta);
}
static void __vtime_account_system(struct task_struct *tsk)
@@ -699,6 +698,9 @@ static void __vtime_account_system(struct task_struct *tsk)
void vtime_account_system(struct task_struct *tsk)
{
+ if (!vtime_delta(tsk))
+ return;
+
write_seqcount_begin(&tsk->vtime_seqcount);
__vtime_account_system(tsk);
write_seqcount_end(&tsk->vtime_seqcount);
@@ -707,7 +709,8 @@ void vtime_account_system(struct task_struct *tsk)
void vtime_gen_account_irq_exit(struct task_struct *tsk)
{
write_seqcount_begin(&tsk->vtime_seqcount);
- __vtime_account_system(tsk);
+ if (vtime_delta(tsk))
+ __vtime_account_system(tsk);
if (context_tracking_in_user())
tsk->vtime_snap_whence = VTIME_USER;
write_seqcount_end(&tsk->vtime_seqcount);
@@ -718,16 +721,19 @@ void vtime_account_user(struct task_struct *tsk)
cputime_t delta_cpu;
write_seqcount_begin(&tsk->vtime_seqcount);
- delta_cpu = get_vtime_delta(tsk);
tsk->vtime_snap_whence = VTIME_SYS;
- account_user_time(tsk, delta_cpu, cputime_to_scaled(delta_cpu));
+ if (vtime_delta(tsk)) {
+ delta_cpu = get_vtime_delta(tsk);
+ account_user_time(tsk, delta_cpu, cputime_to_scaled(delta_cpu));
+ }
write_seqcount_end(&tsk->vtime_seqcount);
}
void vtime_user_enter(struct task_struct *tsk)
{
write_seqcount_begin(&tsk->vtime_seqcount);
- __vtime_account_system(tsk);
+ if (vtime_delta(tsk))
+ __vtime_account_system(tsk);
tsk->vtime_snap_whence = VTIME_USER;
write_seqcount_end(&tsk->vtime_seqcount);
}
@@ -742,7 +748,8 @@ void vtime_guest_enter(struct task_struct *tsk)
* that can thus safely catch up with a tickless delta.
*/
write_seqcount_begin(&tsk->vtime_seqcount);
- __vtime_account_system(tsk);
+ if (vtime_delta(tsk))
+ __vtime_account_system(tsk);
current->flags |= PF_VCPU;
write_seqcount_end(&tsk->vtime_seqcount);
}
@@ -772,7 +779,7 @@ void arch_vtime_task_switch(struct task_struct *prev)
write_seqcount_begin(¤t->vtime_seqcount);
current->vtime_snap_whence = VTIME_SYS;
- current->vtime_snap = sched_clock_cpu(smp_processor_id());
+ current->vtime_snap = jiffies;
write_seqcount_end(¤t->vtime_seqcount);
}
@@ -783,7 +790,7 @@ void vtime_init_idle(struct task_struct *t, int cpu)
local_irq_save(flags);
write_seqcount_begin(&t->vtime_seqcount);
t->vtime_snap_whence = VTIME_SYS;
- t->vtime_snap = sched_clock_cpu(cpu);
+ t->vtime_snap = jiffies;
write_seqcount_end(&t->vtime_seqcount);
local_irq_restore(flags);
}
diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c
index 57b939c81bce..c7a036facbe1 100644
--- a/kernel/sched/deadline.c
+++ b/kernel/sched/deadline.c
@@ -352,7 +352,15 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se,
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
- WARN_ON(!dl_se->dl_new || dl_se->dl_throttled);
+ WARN_ON(dl_time_before(rq_clock(rq), dl_se->deadline));
+
+ /*
+ * We are racing with the deadline timer. So, do nothing because
+ * the deadline timer handler will take care of properly recharging
+ * the runtime and postponing the deadline
+ */
+ if (dl_se->dl_throttled)
+ return;
/*
* We use the regular wall clock time to set deadlines in the
@@ -361,7 +369,6 @@ static inline void setup_new_dl_entity(struct sched_dl_entity *dl_se,
*/
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
dl_se->runtime = pi_se->dl_runtime;
- dl_se->dl_new = 0;
}
/*
@@ -399,6 +406,9 @@ static void replenish_dl_entity(struct sched_dl_entity *dl_se,
dl_se->runtime = pi_se->dl_runtime;
}
+ if (dl_se->dl_yielded && dl_se->runtime > 0)
+ dl_se->runtime = 0;
+
/*
* We keep moving the deadline away until we get some
* available runtime for the entity. This ensures correct
@@ -500,15 +510,6 @@ static void update_dl_entity(struct sched_dl_entity *dl_se,
struct dl_rq *dl_rq = dl_rq_of_se(dl_se);
struct rq *rq = rq_of_dl_rq(dl_rq);
- /*
- * The arrival of a new instance needs special treatment, i.e.,
- * the actual scheduling parameters have to be "renewed".
- */
- if (dl_se->dl_new) {
- setup_new_dl_entity(dl_se, pi_se);
- return;
- }
-
if (dl_time_before(dl_se->deadline, rq_clock(rq)) ||
dl_entity_overflow(dl_se, pi_se, rq_clock(rq))) {
dl_se->deadline = rq_clock(rq) + pi_se->dl_deadline;
@@ -605,16 +606,6 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer)
}
/*
- * This is possible if switched_from_dl() raced against a running
- * callback that took the above !dl_task() path and we've since then
- * switched back into SCHED_DEADLINE.
- *
- * There's nothing to do except drop our task reference.
- */
- if (dl_se->dl_new)
- goto unlock;
-
- /*
* The task might have been boosted by someone else and might be in the
* boosting/deboosting path, its not throttled.
*/
@@ -735,8 +726,11 @@ static void update_curr_dl(struct rq *rq)
* approach need further study.
*/
delta_exec = rq_clock_task(rq) - curr->se.exec_start;
- if (unlikely((s64)delta_exec <= 0))
+ if (unlikely((s64)delta_exec <= 0)) {
+ if (unlikely(dl_se->dl_yielded))
+ goto throttle;
return;
+ }
schedstat_set(curr->se.statistics.exec_max,
max(curr->se.statistics.exec_max, delta_exec));
@@ -749,8 +743,10 @@ static void update_curr_dl(struct rq *rq)
sched_rt_avg_update(rq, delta_exec);
- dl_se->runtime -= dl_se->dl_yielded ? 0 : delta_exec;
- if (dl_runtime_exceeded(dl_se)) {
+ dl_se->runtime -= delta_exec;
+
+throttle:
+ if (dl_runtime_exceeded(dl_se) || dl_se->dl_yielded) {
dl_se->dl_throttled = 1;
__dequeue_task_dl(rq, curr, 0);
if (unlikely(dl_se->dl_boosted || !start_dl_timer(curr)))
@@ -917,7 +913,7 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se,
* parameters of the task might need updating. Otherwise,
* we want a replenishment of its runtime.
*/
- if (dl_se->dl_new || flags & ENQUEUE_WAKEUP)
+ if (flags & ENQUEUE_WAKEUP)
update_dl_entity(dl_se, pi_se);
else if (flags & ENQUEUE_REPLENISH)
replenish_dl_entity(dl_se, pi_se);
@@ -994,18 +990,14 @@ static void dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags)
*/
static void yield_task_dl(struct rq *rq)
{
- struct task_struct *p = rq->curr;
-
/*
* We make the task go to sleep until its current deadline by
* forcing its runtime to zero. This way, update_curr_dl() stops
* it and the bandwidth timer will wake it up and will give it
* new scheduling parameters (thanks to dl_yielded=1).
*/
- if (p->dl.runtime > 0) {
- rq->curr->dl.dl_yielded = 1;
- p->dl.runtime = 0;
- }
+ rq->curr->dl.dl_yielded = 1;
+
update_rq_clock(rq);
update_curr_dl(rq);
/*
@@ -1722,6 +1714,9 @@ static void switched_from_dl(struct rq *rq, struct task_struct *p)
*/
static void switched_to_dl(struct rq *rq, struct task_struct *p)
{
+ if (dl_time_before(p->dl.deadline, rq_clock(rq)))
+ setup_new_dl_entity(&p->dl, &p->dl);
+
if (task_on_rq_queued(p) && rq->curr != p) {
#ifdef CONFIG_SMP
if (p->nr_cpus_allowed > 1 && rq->dl.overloaded)
@@ -1768,8 +1763,7 @@ static void prio_changed_dl(struct rq *rq, struct task_struct *p,
*/
resched_curr(rq);
#endif /* CONFIG_SMP */
- } else
- switched_to_dl(rq, p);
+ }
}
const struct sched_class dl_sched_class = {
diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c
index 641511771ae6..4fbc3bd5ff60 100644
--- a/kernel/sched/debug.c
+++ b/kernel/sched/debug.c
@@ -16,6 +16,7 @@
#include <linux/kallsyms.h>
#include <linux/utsname.h>
#include <linux/mempolicy.h>
+#include <linux/debugfs.h>
#include "sched.h"
@@ -58,6 +59,309 @@ static unsigned long nsec_low(unsigned long long nsec)
#define SPLIT_NS(x) nsec_high(x), nsec_low(x)
+#define SCHED_FEAT(name, enabled) \
+ #name ,
+
+static const char * const sched_feat_names[] = {
+#include "features.h"
+};
+
+#undef SCHED_FEAT
+
+static int sched_feat_show(struct seq_file *m, void *v)
+{
+ int i;
+
+ for (i = 0; i < __SCHED_FEAT_NR; i++) {
+ if (!(sysctl_sched_features & (1UL << i)))
+ seq_puts(m, "NO_");
+ seq_printf(m, "%s ", sched_feat_names[i]);
+ }
+ seq_puts(m, "\n");
+
+ return 0;
+}
+
+#ifdef HAVE_JUMP_LABEL
+
+#define jump_label_key__true STATIC_KEY_INIT_TRUE
+#define jump_label_key__false STATIC_KEY_INIT_FALSE
+
+#define SCHED_FEAT(name, enabled) \
+ jump_label_key__##enabled ,
+
+struct static_key sched_feat_keys[__SCHED_FEAT_NR] = {
+#include "features.h"
+};
+
+#undef SCHED_FEAT
+
+static void sched_feat_disable(int i)
+{
+ static_key_disable(&sched_feat_keys[i]);
+}
+
+static void sched_feat_enable(int i)
+{
+ static_key_enable(&sched_feat_keys[i]);
+}
+#else
+static void sched_feat_disable(int i) { };
+static void sched_feat_enable(int i) { };
+#endif /* HAVE_JUMP_LABEL */
+
+static int sched_feat_set(char *cmp)
+{
+ int i;
+ int neg = 0;
+
+ if (strncmp(cmp, "NO_", 3) == 0) {
+ neg = 1;
+ cmp += 3;
+ }
+
+ for (i = 0; i < __SCHED_FEAT_NR; i++) {
+ if (strcmp(cmp, sched_feat_names[i]) == 0) {
+ if (neg) {
+ sysctl_sched_features &= ~(1UL << i);
+ sched_feat_disable(i);
+ } else {
+ sysctl_sched_features |= (1UL << i);
+ sched_feat_enable(i);
+ }
+ break;
+ }
+ }
+
+ return i;
+}
+
+static ssize_t
+sched_feat_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ char *cmp;
+ int i;
+ struct inode *inode;
+
+ if (cnt > 63)
+ cnt = 63;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+ cmp = strstrip(buf);
+
+ /* Ensure the static_key remains in a consistent state */
+ inode = file_inode(filp);
+ inode_lock(inode);
+ i = sched_feat_set(cmp);
+ inode_unlock(inode);
+ if (i == __SCHED_FEAT_NR)
+ return -EINVAL;
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static int sched_feat_open(struct inode *inode, struct file *filp)
+{
+ return single_open(filp, sched_feat_show, NULL);
+}
+
+static const struct file_operations sched_feat_fops = {
+ .open = sched_feat_open,
+ .write = sched_feat_write,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+};
+
+static __init int sched_init_debug(void)
+{
+ debugfs_create_file("sched_features", 0644, NULL, NULL,
+ &sched_feat_fops);
+
+ return 0;
+}
+late_initcall(sched_init_debug);
+
+#ifdef CONFIG_SMP
+
+#ifdef CONFIG_SYSCTL
+
+static struct ctl_table sd_ctl_dir[] = {
+ {
+ .procname = "sched_domain",
+ .mode = 0555,
+ },
+ {}
+};
+
+static struct ctl_table sd_ctl_root[] = {
+ {
+ .procname = "kernel",
+ .mode = 0555,
+ .child = sd_ctl_dir,
+ },
+ {}
+};
+
+static struct ctl_table *sd_alloc_ctl_entry(int n)
+{
+ struct ctl_table *entry =
+ kcalloc(n, sizeof(struct ctl_table), GFP_KERNEL);
+
+ return entry;
+}
+
+static void sd_free_ctl_entry(struct ctl_table **tablep)
+{
+ struct ctl_table *entry;
+
+ /*
+ * In the intermediate directories, both the child directory and
+ * procname are dynamically allocated and could fail but the mode
+ * will always be set. In the lowest directory the names are
+ * static strings and all have proc handlers.
+ */
+ for (entry = *tablep; entry->mode; entry++) {
+ if (entry->child)
+ sd_free_ctl_entry(&entry->child);
+ if (entry->proc_handler == NULL)
+ kfree(entry->procname);
+ }
+
+ kfree(*tablep);
+ *tablep = NULL;
+}
+
+static int min_load_idx = 0;
+static int max_load_idx = CPU_LOAD_IDX_MAX-1;
+
+static void
+set_table_entry(struct ctl_table *entry,
+ const char *procname, void *data, int maxlen,
+ umode_t mode, proc_handler *proc_handler,
+ bool load_idx)
+{
+ entry->procname = procname;
+ entry->data = data;
+ entry->maxlen = maxlen;
+ entry->mode = mode;
+ entry->proc_handler = proc_handler;
+
+ if (load_idx) {
+ entry->extra1 = &min_load_idx;
+ entry->extra2 = &max_load_idx;
+ }
+}
+
+static struct ctl_table *
+sd_alloc_ctl_domain_table(struct sched_domain *sd)
+{
+ struct ctl_table *table = sd_alloc_ctl_entry(14);
+
+ if (table == NULL)
+ return NULL;
+
+ set_table_entry(&table[0], "min_interval", &sd->min_interval,
+ sizeof(long), 0644, proc_doulongvec_minmax, false);
+ set_table_entry(&table[1], "max_interval", &sd->max_interval,
+ sizeof(long), 0644, proc_doulongvec_minmax, false);
+ set_table_entry(&table[2], "busy_idx", &sd->busy_idx,
+ sizeof(int), 0644, proc_dointvec_minmax, true);
+ set_table_entry(&table[3], "idle_idx", &sd->idle_idx,
+ sizeof(int), 0644, proc_dointvec_minmax, true);
+ set_table_entry(&table[4], "newidle_idx", &sd->newidle_idx,
+ sizeof(int), 0644, proc_dointvec_minmax, true);
+ set_table_entry(&table[5], "wake_idx", &sd->wake_idx,
+ sizeof(int), 0644, proc_dointvec_minmax, true);
+ set_table_entry(&table[6], "forkexec_idx", &sd->forkexec_idx,
+ sizeof(int), 0644, proc_dointvec_minmax, true);
+ set_table_entry(&table[7], "busy_factor", &sd->busy_factor,
+ sizeof(int), 0644, proc_dointvec_minmax, false);
+ set_table_entry(&table[8], "imbalance_pct", &sd->imbalance_pct,
+ sizeof(int), 0644, proc_dointvec_minmax, false);
+ set_table_entry(&table[9], "cache_nice_tries",
+ &sd->cache_nice_tries,
+ sizeof(int), 0644, proc_dointvec_minmax, false);
+ set_table_entry(&table[10], "flags", &sd->flags,
+ sizeof(int), 0644, proc_dointvec_minmax, false);
+ set_table_entry(&table[11], "max_newidle_lb_cost",
+ &sd->max_newidle_lb_cost,
+ sizeof(long), 0644, proc_doulongvec_minmax, false);
+ set_table_entry(&table[12], "name", sd->name,
+ CORENAME_MAX_SIZE, 0444, proc_dostring, false);
+ /* &table[13] is terminator */
+
+ return table;
+}
+
+static struct ctl_table *sd_alloc_ctl_cpu_table(int cpu)
+{
+ struct ctl_table *entry, *table;
+ struct sched_domain *sd;
+ int domain_num = 0, i;
+ char buf[32];
+
+ for_each_domain(cpu, sd)
+ domain_num++;
+ entry = table = sd_alloc_ctl_entry(domain_num + 1);
+ if (table == NULL)
+ return NULL;
+
+ i = 0;
+ for_each_domain(cpu, sd) {
+ snprintf(buf, 32, "domain%d", i);
+ entry->procname = kstrdup(buf, GFP_KERNEL);
+ entry->mode = 0555;
+ entry->child = sd_alloc_ctl_domain_table(sd);
+ entry++;
+ i++;
+ }
+ return table;
+}
+
+static struct ctl_table_header *sd_sysctl_header;
+void register_sched_domain_sysctl(void)
+{
+ int i, cpu_num = num_possible_cpus();
+ struct ctl_table *entry = sd_alloc_ctl_entry(cpu_num + 1);
+ char buf[32];
+
+ WARN_ON(sd_ctl_dir[0].child);
+ sd_ctl_dir[0].child = entry;
+
+ if (entry == NULL)
+ return;
+
+ for_each_possible_cpu(i) {
+ snprintf(buf, 32, "cpu%d", i);
+ entry->procname = kstrdup(buf, GFP_KERNEL);
+ entry->mode = 0555;
+ entry->child = sd_alloc_ctl_cpu_table(i);
+ entry++;
+ }
+
+ WARN_ON(sd_sysctl_header);
+ sd_sysctl_header = register_sysctl_table(sd_ctl_root);
+}
+
+/* may be called multiple times per register */
+void unregister_sched_domain_sysctl(void)
+{
+ unregister_sysctl_table(sd_sysctl_header);
+ sd_sysctl_header = NULL;
+ if (sd_ctl_dir[0].child)
+ sd_free_ctl_entry(&sd_ctl_dir[0].child);
+}
+#endif /* CONFIG_SYSCTL */
+#endif /* CONFIG_SMP */
+
#ifdef CONFIG_FAIR_GROUP_SCHED
static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
{
@@ -75,16 +379,18 @@ static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group
PN(se->vruntime);
PN(se->sum_exec_runtime);
#ifdef CONFIG_SCHEDSTATS
- PN(se->statistics.wait_start);
- PN(se->statistics.sleep_start);
- PN(se->statistics.block_start);
- PN(se->statistics.sleep_max);
- PN(se->statistics.block_max);
- PN(se->statistics.exec_max);
- PN(se->statistics.slice_max);
- PN(se->statistics.wait_max);
- PN(se->statistics.wait_sum);
- P(se->statistics.wait_count);
+ if (schedstat_enabled()) {
+ PN(se->statistics.wait_start);
+ PN(se->statistics.sleep_start);
+ PN(se->statistics.block_start);
+ PN(se->statistics.sleep_max);
+ PN(se->statistics.block_max);
+ PN(se->statistics.exec_max);
+ PN(se->statistics.slice_max);
+ PN(se->statistics.wait_max);
+ PN(se->statistics.wait_sum);
+ P(se->statistics.wait_count);
+ }
#endif
P(se->load.weight);
#ifdef CONFIG_SMP
@@ -122,10 +428,12 @@ print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
(long long)(p->nvcsw + p->nivcsw),
p->prio);
#ifdef CONFIG_SCHEDSTATS
- SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
- SPLIT_NS(p->se.statistics.wait_sum),
- SPLIT_NS(p->se.sum_exec_runtime),
- SPLIT_NS(p->se.statistics.sum_sleep_runtime));
+ if (schedstat_enabled()) {
+ SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
+ SPLIT_NS(p->se.statistics.wait_sum),
+ SPLIT_NS(p->se.sum_exec_runtime),
+ SPLIT_NS(p->se.statistics.sum_sleep_runtime));
+ }
#else
SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
0LL, 0L,
@@ -258,8 +566,17 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
{
+ struct dl_bw *dl_bw;
+
SEQ_printf(m, "\ndl_rq[%d]:\n", cpu);
SEQ_printf(m, " .%-30s: %ld\n", "dl_nr_running", dl_rq->dl_nr_running);
+#ifdef CONFIG_SMP
+ dl_bw = &cpu_rq(cpu)->rd->dl_bw;
+#else
+ dl_bw = &dl_rq->dl_bw;
+#endif
+ SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->bw", dl_bw->bw);
+ SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->total_bw", dl_bw->total_bw);
}
extern __read_mostly int sched_clock_running;
@@ -313,17 +630,18 @@ do { \
#define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
#define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
- P(yld_count);
-
- P(sched_count);
- P(sched_goidle);
#ifdef CONFIG_SMP
P64(avg_idle);
P64(max_idle_balance_cost);
#endif
- P(ttwu_count);
- P(ttwu_local);
+ if (schedstat_enabled()) {
+ P(yld_count);
+ P(sched_count);
+ P(sched_goidle);
+ P(ttwu_count);
+ P(ttwu_local);
+ }
#undef P
#undef P64
@@ -569,38 +887,39 @@ void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
nr_switches = p->nvcsw + p->nivcsw;
#ifdef CONFIG_SCHEDSTATS
- PN(se.statistics.sum_sleep_runtime);
- PN(se.statistics.wait_start);
- PN(se.statistics.sleep_start);
- PN(se.statistics.block_start);
- PN(se.statistics.sleep_max);
- PN(se.statistics.block_max);
- PN(se.statistics.exec_max);
- PN(se.statistics.slice_max);
- PN(se.statistics.wait_max);
- PN(se.statistics.wait_sum);
- P(se.statistics.wait_count);
- PN(se.statistics.iowait_sum);
- P(se.statistics.iowait_count);
P(se.nr_migrations);
- P(se.statistics.nr_migrations_cold);
- P(se.statistics.nr_failed_migrations_affine);
- P(se.statistics.nr_failed_migrations_running);
- P(se.statistics.nr_failed_migrations_hot);
- P(se.statistics.nr_forced_migrations);
- P(se.statistics.nr_wakeups);
- P(se.statistics.nr_wakeups_sync);
- P(se.statistics.nr_wakeups_migrate);
- P(se.statistics.nr_wakeups_local);
- P(se.statistics.nr_wakeups_remote);
- P(se.statistics.nr_wakeups_affine);
- P(se.statistics.nr_wakeups_affine_attempts);
- P(se.statistics.nr_wakeups_passive);
- P(se.statistics.nr_wakeups_idle);
- {
+ if (schedstat_enabled()) {
u64 avg_atom, avg_per_cpu;
+ PN(se.statistics.sum_sleep_runtime);
+ PN(se.statistics.wait_start);
+ PN(se.statistics.sleep_start);
+ PN(se.statistics.block_start);
+ PN(se.statistics.sleep_max);
+ PN(se.statistics.block_max);
+ PN(se.statistics.exec_max);
+ PN(se.statistics.slice_max);
+ PN(se.statistics.wait_max);
+ PN(se.statistics.wait_sum);
+ P(se.statistics.wait_count);
+ PN(se.statistics.iowait_sum);
+ P(se.statistics.iowait_count);
+ P(se.statistics.nr_migrations_cold);
+ P(se.statistics.nr_failed_migrations_affine);
+ P(se.statistics.nr_failed_migrations_running);
+ P(se.statistics.nr_failed_migrations_hot);
+ P(se.statistics.nr_forced_migrations);
+ P(se.statistics.nr_wakeups);
+ P(se.statistics.nr_wakeups_sync);
+ P(se.statistics.nr_wakeups_migrate);
+ P(se.statistics.nr_wakeups_local);
+ P(se.statistics.nr_wakeups_remote);
+ P(se.statistics.nr_wakeups_affine);
+ P(se.statistics.nr_wakeups_affine_attempts);
+ P(se.statistics.nr_wakeups_passive);
+ P(se.statistics.nr_wakeups_idle);
+
avg_atom = p->se.sum_exec_runtime;
if (nr_switches)
avg_atom = div64_ul(avg_atom, nr_switches);
diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c
index 56b7d4b83947..33130529e9b5 100644
--- a/kernel/sched/fair.c
+++ b/kernel/sched/fair.c
@@ -20,8 +20,8 @@
* Copyright (C) 2007 Red Hat, Inc., Peter Zijlstra
*/
-#include <linux/latencytop.h>
#include <linux/sched.h>
+#include <linux/latencytop.h>
#include <linux/cpumask.h>
#include <linux/cpuidle.h>
#include <linux/slab.h>
@@ -755,7 +755,9 @@ static void
update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
struct task_struct *p;
- u64 delta = rq_clock(rq_of(cfs_rq)) - se->statistics.wait_start;
+ u64 delta;
+
+ delta = rq_clock(rq_of(cfs_rq)) - se->statistics.wait_start;
if (entity_is_task(se)) {
p = task_of(se);
@@ -776,22 +778,12 @@ update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
se->statistics.wait_sum += delta;
se->statistics.wait_start = 0;
}
-#else
-static inline void
-update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
-}
-
-static inline void
-update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
-{
-}
-#endif
/*
* Task is being enqueued - update stats:
*/
-static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+static inline void
+update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
{
/*
* Are we enqueueing a waiting task? (for current tasks
@@ -802,7 +794,7 @@ static void update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
}
static inline void
-update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
{
/*
* Mark the end of the wait period if dequeueing a
@@ -810,8 +802,41 @@ update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se)
*/
if (se != cfs_rq->curr)
update_stats_wait_end(cfs_rq, se);
+
+ if (flags & DEQUEUE_SLEEP) {
+ if (entity_is_task(se)) {
+ struct task_struct *tsk = task_of(se);
+
+ if (tsk->state & TASK_INTERRUPTIBLE)
+ se->statistics.sleep_start = rq_clock(rq_of(cfs_rq));
+ if (tsk->state & TASK_UNINTERRUPTIBLE)
+ se->statistics.block_start = rq_clock(rq_of(cfs_rq));
+ }
+ }
+
+}
+#else
+static inline void
+update_stats_wait_start(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
}
+static inline void
+update_stats_wait_end(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+}
+
+static inline void
+update_stats_enqueue(struct cfs_rq *cfs_rq, struct sched_entity *se)
+{
+}
+
+static inline void
+update_stats_dequeue(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
+{
+}
+#endif
+
/*
* We are picking a new current task - update its stats:
*/
@@ -907,10 +932,11 @@ struct numa_group {
spinlock_t lock; /* nr_tasks, tasks */
int nr_tasks;
pid_t gid;
+ int active_nodes;
struct rcu_head rcu;
- nodemask_t active_nodes;
unsigned long total_faults;
+ unsigned long max_faults_cpu;
/*
* Faults_cpu is used to decide whether memory should move
* towards the CPU. As a consequence, these stats are weighted
@@ -969,6 +995,18 @@ static inline unsigned long group_faults_cpu(struct numa_group *group, int nid)
group->faults_cpu[task_faults_idx(NUMA_MEM, nid, 1)];
}
+/*
+ * A node triggering more than 1/3 as many NUMA faults as the maximum is
+ * considered part of a numa group's pseudo-interleaving set. Migrations
+ * between these nodes are slowed down, to allow things to settle down.
+ */
+#define ACTIVE_NODE_FRACTION 3
+
+static bool numa_is_active_node(int nid, struct numa_group *ng)
+{
+ return group_faults_cpu(ng, nid) * ACTIVE_NODE_FRACTION > ng->max_faults_cpu;
+}
+
/* Handle placement on systems where not all nodes are directly connected. */
static unsigned long score_nearby_nodes(struct task_struct *p, int nid,
int maxdist, bool task)
@@ -1118,27 +1156,23 @@ bool should_numa_migrate_memory(struct task_struct *p, struct page * page,
return true;
/*
- * Do not migrate if the destination is not a node that
- * is actively used by this numa group.
+ * Destination node is much more heavily used than the source
+ * node? Allow migration.
*/
- if (!node_isset(dst_nid, ng->active_nodes))
- return false;
-
- /*
- * Source is a node that is not actively used by this
- * numa group, while the destination is. Migrate.
- */
- if (!node_isset(src_nid, ng->active_nodes))
+ if (group_faults_cpu(ng, dst_nid) > group_faults_cpu(ng, src_nid) *
+ ACTIVE_NODE_FRACTION)
return true;
/*
- * Both source and destination are nodes in active
- * use by this numa group. Maximize memory bandwidth
- * by migrating from more heavily used groups, to less
- * heavily used ones, spreading the load around.
- * Use a 1/4 hysteresis to avoid spurious page movement.
+ * Distribute memory according to CPU & memory use on each node,
+ * with 3/4 hysteresis to avoid unnecessary memory migrations:
+ *
+ * faults_cpu(dst) 3 faults_cpu(src)
+ * --------------- * - > ---------------
+ * faults_mem(dst) 4 faults_mem(src)
*/
- return group_faults(p, dst_nid) < (group_faults(p, src_nid) * 3 / 4);
+ return group_faults_cpu(ng, dst_nid) * group_faults(p, src_nid) * 3 >
+ group_faults_cpu(ng, src_nid) * group_faults(p, dst_nid) * 4;
}
static unsigned long weighted_cpuload(const int cpu);
@@ -1484,7 +1518,7 @@ static int task_numa_migrate(struct task_struct *p)
.best_task = NULL,
.best_imp = 0,
- .best_cpu = -1
+ .best_cpu = -1,
};
struct sched_domain *sd;
unsigned long taskweight, groupweight;
@@ -1536,8 +1570,7 @@ static int task_numa_migrate(struct task_struct *p)
* multiple NUMA nodes; in order to better consolidate the group,
* we need to check other locations.
*/
- if (env.best_cpu == -1 || (p->numa_group &&
- nodes_weight(p->numa_group->active_nodes) > 1)) {
+ if (env.best_cpu == -1 || (p->numa_group && p->numa_group->active_nodes > 1)) {
for_each_online_node(nid) {
if (nid == env.src_nid || nid == p->numa_preferred_nid)
continue;
@@ -1572,12 +1605,14 @@ static int task_numa_migrate(struct task_struct *p)
* trying for a better one later. Do not set the preferred node here.
*/
if (p->numa_group) {
+ struct numa_group *ng = p->numa_group;
+
if (env.best_cpu == -1)
nid = env.src_nid;
else
nid = env.dst_nid;
- if (node_isset(nid, p->numa_group->active_nodes))
+ if (ng->active_nodes > 1 && numa_is_active_node(env.dst_nid, ng))
sched_setnuma(p, env.dst_nid);
}
@@ -1627,20 +1662,15 @@ static void numa_migrate_preferred(struct task_struct *p)
}
/*
- * Find the nodes on which the workload is actively running. We do this by
+ * Find out how many nodes on the workload is actively running on. Do this by
* tracking the nodes from which NUMA hinting faults are triggered. This can
* be different from the set of nodes where the workload's memory is currently
* located.
- *
- * The bitmask is used to make smarter decisions on when to do NUMA page
- * migrations, To prevent flip-flopping, and excessive page migrations, nodes
- * are added when they cause over 6/16 of the maximum number of faults, but
- * only removed when they drop below 3/16.
*/
-static void update_numa_active_node_mask(struct numa_group *numa_group)
+static void numa_group_count_active_nodes(struct numa_group *numa_group)
{
unsigned long faults, max_faults = 0;
- int nid;
+ int nid, active_nodes = 0;
for_each_online_node(nid) {
faults = group_faults_cpu(numa_group, nid);
@@ -1650,12 +1680,12 @@ static void update_numa_active_node_mask(struct numa_group *numa_group)
for_each_online_node(nid) {
faults = group_faults_cpu(numa_group, nid);
- if (!node_isset(nid, numa_group->active_nodes)) {
- if (faults > max_faults * 6 / 16)
- node_set(nid, numa_group->active_nodes);
- } else if (faults < max_faults * 3 / 16)
- node_clear(nid, numa_group->active_nodes);
+ if (faults * ACTIVE_NODE_FRACTION > max_faults)
+ active_nodes++;
}
+
+ numa_group->max_faults_cpu = max_faults;
+ numa_group->active_nodes = active_nodes;
}
/*
@@ -1946,7 +1976,7 @@ static void task_numa_placement(struct task_struct *p)
update_task_scan_period(p, fault_types[0], fault_types[1]);
if (p->numa_group) {
- update_numa_active_node_mask(p->numa_group);
+ numa_group_count_active_nodes(p->numa_group);
spin_unlock_irq(group_lock);
max_nid = preferred_group_nid(p, max_group_nid);
}
@@ -1990,14 +2020,14 @@ static void task_numa_group(struct task_struct *p, int cpupid, int flags,
return;
atomic_set(&grp->refcount, 1);
+ grp->active_nodes = 1;
+ grp->max_faults_cpu = 0;
spin_lock_init(&grp->lock);
grp->gid = p->pid;
/* Second half of the array tracks nids where faults happen */
grp->faults_cpu = grp->faults + NR_NUMA_HINT_FAULT_TYPES *
nr_node_ids;
- node_set(task_node(current), grp->active_nodes);
-
for (i = 0; i < NR_NUMA_HINT_FAULT_STATS * nr_node_ids; i++)
grp->faults[i] = p->numa_faults[i];
@@ -2111,6 +2141,7 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags)
bool migrated = flags & TNF_MIGRATED;
int cpu_node = task_node(current);
int local = !!(flags & TNF_FAULT_LOCAL);
+ struct numa_group *ng;
int priv;
if (!static_branch_likely(&sched_numa_balancing))
@@ -2151,9 +2182,10 @@ void task_numa_fault(int last_cpupid, int mem_node, int pages, int flags)
* actively using should be counted as local. This allows the
* scan rate to slow down when a workload has settled down.
*/
- if (!priv && !local && p->numa_group &&
- node_isset(cpu_node, p->numa_group->active_nodes) &&
- node_isset(mem_node, p->numa_group->active_nodes))
+ ng = p->numa_group;
+ if (!priv && !local && ng && ng->active_nodes > 1 &&
+ numa_is_active_node(cpu_node, ng) &&
+ numa_is_active_node(mem_node, ng))
local = 1;
task_numa_placement(p);
@@ -3102,6 +3134,26 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
static void check_enqueue_throttle(struct cfs_rq *cfs_rq);
+static inline void check_schedstat_required(void)
+{
+#ifdef CONFIG_SCHEDSTATS
+ if (schedstat_enabled())
+ return;
+
+ /* Force schedstat enabled if a dependent tracepoint is active */
+ if (trace_sched_stat_wait_enabled() ||
+ trace_sched_stat_sleep_enabled() ||
+ trace_sched_stat_iowait_enabled() ||
+ trace_sched_stat_blocked_enabled() ||
+ trace_sched_stat_runtime_enabled()) {
+ pr_warn_once("Scheduler tracepoints stat_sleep, stat_iowait, "
+ "stat_blocked and stat_runtime require the "
+ "kernel parameter schedstats=enabled or "
+ "kernel.sched_schedstats=1\n");
+ }
+#endif
+}
+
static void
enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
{
@@ -3122,11 +3174,15 @@ enqueue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
if (flags & ENQUEUE_WAKEUP) {
place_entity(cfs_rq, se, 0);
- enqueue_sleeper(cfs_rq, se);
+ if (schedstat_enabled())
+ enqueue_sleeper(cfs_rq, se);
}
- update_stats_enqueue(cfs_rq, se);
- check_spread(cfs_rq, se);
+ check_schedstat_required();
+ if (schedstat_enabled()) {
+ update_stats_enqueue(cfs_rq, se);
+ check_spread(cfs_rq, se);
+ }
if (se != cfs_rq->curr)
__enqueue_entity(cfs_rq, se);
se->on_rq = 1;
@@ -3193,19 +3249,8 @@ dequeue_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int flags)
update_curr(cfs_rq);
dequeue_entity_load_avg(cfs_rq, se);
- update_stats_dequeue(cfs_rq, se);
- if (flags & DEQUEUE_SLEEP) {
-#ifdef CONFIG_SCHEDSTATS
- if (entity_is_task(se)) {
- struct task_struct *tsk = task_of(se);
-
- if (tsk->state & TASK_INTERRUPTIBLE)
- se->statistics.sleep_start = rq_clock(rq_of(cfs_rq));
- if (tsk->state & TASK_UNINTERRUPTIBLE)
- se->statistics.block_start = rq_clock(rq_of(cfs_rq));
- }
-#endif
- }
+ if (schedstat_enabled())
+ update_stats_dequeue(cfs_rq, se, flags);
clear_buddies(cfs_rq, se);
@@ -3279,7 +3324,8 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
* a CPU. So account for the time it spent waiting on the
* runqueue.
*/
- update_stats_wait_end(cfs_rq, se);
+ if (schedstat_enabled())
+ update_stats_wait_end(cfs_rq, se);
__dequeue_entity(cfs_rq, se);
update_load_avg(se, 1);
}
@@ -3292,7 +3338,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se)
* least twice that of our own weight (i.e. dont track it
* when there are only lesser-weight tasks around):
*/
- if (rq_of(cfs_rq)->load.weight >= 2*se->load.weight) {
+ if (schedstat_enabled() && rq_of(cfs_rq)->load.weight >= 2*se->load.weight) {
se->statistics.slice_max = max(se->statistics.slice_max,
se->sum_exec_runtime - se->prev_sum_exec_runtime);
}
@@ -3375,9 +3421,13 @@ static void put_prev_entity(struct cfs_rq *cfs_rq, struct sched_entity *prev)
/* throttle cfs_rqs exceeding runtime */
check_cfs_rq_runtime(cfs_rq);
- check_spread(cfs_rq, prev);
+ if (schedstat_enabled()) {
+ check_spread(cfs_rq, prev);
+ if (prev->on_rq)
+ update_stats_wait_start(cfs_rq, prev);
+ }
+
if (prev->on_rq) {
- update_stats_wait_start(cfs_rq, prev);
/* Put 'current' back into the tree. */
__enqueue_entity(cfs_rq, prev);
/* in !on_rq case, update occurred at dequeue */
@@ -4459,9 +4509,17 @@ static void __update_cpu_load(struct rq *this_rq, unsigned long this_load,
/* scale is effectively 1 << i now, and >> i divides by scale */
- old_load = this_rq->cpu_load[i] - tickless_load;
+ old_load = this_rq->cpu_load[i];
old_load = decay_load_missed(old_load, pending_updates - 1, i);
- old_load += tickless_load;
+ if (tickless_load) {
+ old_load -= decay_load_missed(tickless_load, pending_updates - 1, i);
+ /*
+ * old_load can never be a negative value because a
+ * decayed tickless_load cannot be greater than the
+ * original tickless_load.
+ */
+ old_load += tickless_load;
+ }
new_load = this_load;
/*
* Round up the averaging division if load is increasing. This
@@ -4484,6 +4542,25 @@ static unsigned long weighted_cpuload(const int cpu)
}
#ifdef CONFIG_NO_HZ_COMMON
+static void __update_cpu_load_nohz(struct rq *this_rq,
+ unsigned long curr_jiffies,
+ unsigned long load,
+ int active)
+{
+ unsigned long pending_updates;
+
+ pending_updates = curr_jiffies - this_rq->last_load_update_tick;
+ if (pending_updates) {
+ this_rq->last_load_update_tick = curr_jiffies;
+ /*
+ * In the regular NOHZ case, we were idle, this means load 0.
+ * In the NOHZ_FULL case, we were non-idle, we should consider
+ * its weighted load.
+ */
+ __update_cpu_load(this_rq, load, pending_updates, active);
+ }
+}
+
/*
* There is no sane way to deal with nohz on smp when using jiffies because the
* cpu doing the jiffies update might drift wrt the cpu doing the jiffy reading
@@ -4501,22 +4578,15 @@ static unsigned long weighted_cpuload(const int cpu)
* Called from nohz_idle_balance() to update the load ratings before doing the
* idle balance.
*/
-static void update_idle_cpu_load(struct rq *this_rq)
+static void update_cpu_load_idle(struct rq *this_rq)
{
- unsigned long curr_jiffies = READ_ONCE(jiffies);
- unsigned long load = weighted_cpuload(cpu_of(this_rq));
- unsigned long pending_updates;
-
/*
* bail if there's load or we're actually up-to-date.
*/
- if (load || curr_jiffies == this_rq->last_load_update_tick)
+ if (weighted_cpuload(cpu_of(this_rq)))
return;
- pending_updates = curr_jiffies - this_rq->last_load_update_tick;
- this_rq->last_load_update_tick = curr_jiffies;
-
- __update_cpu_load(this_rq, load, pending_updates, 0);
+ __update_cpu_load_nohz(this_rq, READ_ONCE(jiffies), 0, 0);
}
/*
@@ -4527,22 +4597,12 @@ void update_cpu_load_nohz(int active)
struct rq *this_rq = this_rq();
unsigned long curr_jiffies = READ_ONCE(jiffies);
unsigned long load = active ? weighted_cpuload(cpu_of(this_rq)) : 0;
- unsigned long pending_updates;
if (curr_jiffies == this_rq->last_load_update_tick)
return;
raw_spin_lock(&this_rq->lock);
- pending_updates = curr_jiffies - this_rq->last_load_update_tick;
- if (pending_updates) {
- this_rq->last_load_update_tick = curr_jiffies;
- /*
- * In the regular NOHZ case, we were idle, this means load 0.
- * In the NOHZ_FULL case, we were non-idle, we should consider
- * its weighted load.
- */
- __update_cpu_load(this_rq, load, pending_updates, active);
- }
+ __update_cpu_load_nohz(this_rq, curr_jiffies, load, active);
raw_spin_unlock(&this_rq->lock);
}
#endif /* CONFIG_NO_HZ */
@@ -4554,7 +4614,7 @@ void update_cpu_load_active(struct rq *this_rq)
{
unsigned long load = weighted_cpuload(cpu_of(this_rq));
/*
- * See the mess around update_idle_cpu_load() / update_cpu_load_nohz().
+ * See the mess around update_cpu_load_idle() / update_cpu_load_nohz().
*/
this_rq->last_load_update_tick = jiffies;
__update_cpu_load(this_rq, load, 1, 1);
@@ -7848,7 +7908,7 @@ static void nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle)
if (time_after_eq(jiffies, rq->next_balance)) {
raw_spin_lock_irq(&rq->lock);
update_rq_clock(rq);
- update_idle_cpu_load(rq);
+ update_cpu_load_idle(rq);
raw_spin_unlock_irq(&rq->lock);
rebalance_domains(rq, CPU_IDLE);
}
@@ -8234,11 +8294,8 @@ void free_fair_sched_group(struct task_group *tg)
for_each_possible_cpu(i) {
if (tg->cfs_rq)
kfree(tg->cfs_rq[i]);
- if (tg->se) {
- if (tg->se[i])
- remove_entity_load_avg(tg->se[i]);
+ if (tg->se)
kfree(tg->se[i]);
- }
}
kfree(tg->cfs_rq);
@@ -8286,21 +8343,29 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
return 0;
}
-void unregister_fair_sched_group(struct task_group *tg, int cpu)
+void unregister_fair_sched_group(struct task_group *tg)
{
- struct rq *rq = cpu_rq(cpu);
unsigned long flags;
+ struct rq *rq;
+ int cpu;
- /*
- * Only empty task groups can be destroyed; so we can speculatively
- * check on_list without danger of it being re-added.
- */
- if (!tg->cfs_rq[cpu]->on_list)
- return;
+ for_each_possible_cpu(cpu) {
+ if (tg->se[cpu])
+ remove_entity_load_avg(tg->se[cpu]);
- raw_spin_lock_irqsave(&rq->lock, flags);
- list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
- raw_spin_unlock_irqrestore(&rq->lock, flags);
+ /*
+ * Only empty task groups can be destroyed; so we can speculatively
+ * check on_list without danger of it being re-added.
+ */
+ if (!tg->cfs_rq[cpu]->on_list)
+ continue;
+
+ rq = cpu_rq(cpu);
+
+ raw_spin_lock_irqsave(&rq->lock, flags);
+ list_del_leaf_cfs_rq(tg->cfs_rq[cpu]);
+ raw_spin_unlock_irqrestore(&rq->lock, flags);
+ }
}
void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
@@ -8382,7 +8447,7 @@ int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent)
return 1;
}
-void unregister_fair_sched_group(struct task_group *tg, int cpu) { }
+void unregister_fair_sched_group(struct task_group *tg) { }
#endif /* CONFIG_FAIR_GROUP_SCHED */
diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c
index 8ec86abe0ea1..a774b4dbf291 100644
--- a/kernel/sched/rt.c
+++ b/kernel/sched/rt.c
@@ -58,7 +58,15 @@ static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
raw_spin_lock(&rt_b->rt_runtime_lock);
if (!rt_b->rt_period_active) {
rt_b->rt_period_active = 1;
- hrtimer_forward_now(&rt_b->rt_period_timer, rt_b->rt_period);
+ /*
+ * SCHED_DEADLINE updates the bandwidth, as a run away
+ * RT task with a DL task could hog a CPU. But DL does
+ * not reset the period. If a deadline task was running
+ * without an RT task running, it can cause RT tasks to
+ * throttle when they start up. Kick the timer right away
+ * to update the period.
+ */
+ hrtimer_forward_now(&rt_b->rt_period_timer, ns_to_ktime(0));
hrtimer_start_expires(&rt_b->rt_period_timer, HRTIMER_MODE_ABS_PINNED);
}
raw_spin_unlock(&rt_b->rt_runtime_lock);
@@ -436,7 +444,7 @@ static void dequeue_top_rt_rq(struct rt_rq *rt_rq);
static inline int on_rt_rq(struct sched_rt_entity *rt_se)
{
- return !list_empty(&rt_se->run_list);
+ return rt_se->on_rq;
}
#ifdef CONFIG_RT_GROUP_SCHED
@@ -482,8 +490,8 @@ static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
return rt_se->my_q;
}
-static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head);
-static void dequeue_rt_entity(struct sched_rt_entity *rt_se);
+static void enqueue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags);
+static void dequeue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags);
static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
{
@@ -499,7 +507,7 @@ static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
if (!rt_se)
enqueue_top_rt_rq(rt_rq);
else if (!on_rt_rq(rt_se))
- enqueue_rt_entity(rt_se, false);
+ enqueue_rt_entity(rt_se, 0);
if (rt_rq->highest_prio.curr < curr->prio)
resched_curr(rq);
@@ -516,7 +524,7 @@ static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
if (!rt_se)
dequeue_top_rt_rq(rt_rq);
else if (on_rt_rq(rt_se))
- dequeue_rt_entity(rt_se);
+ dequeue_rt_entity(rt_se, 0);
}
static inline int rt_rq_throttled(struct rt_rq *rt_rq)
@@ -1166,7 +1174,30 @@ void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
dec_rt_group(rt_se, rt_rq);
}
-static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
+/*
+ * Change rt_se->run_list location unless SAVE && !MOVE
+ *
+ * assumes ENQUEUE/DEQUEUE flags match
+ */
+static inline bool move_entity(unsigned int flags)
+{
+ if ((flags & (DEQUEUE_SAVE | DEQUEUE_MOVE)) == DEQUEUE_SAVE)
+ return false;
+
+ return true;
+}
+
+static void __delist_rt_entity(struct sched_rt_entity *rt_se, struct rt_prio_array *array)
+{
+ list_del_init(&rt_se->run_list);
+
+ if (list_empty(array->queue + rt_se_prio(rt_se)))
+ __clear_bit(rt_se_prio(rt_se), array->bitmap);
+
+ rt_se->on_list = 0;
+}
+
+static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags)
{
struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
struct rt_prio_array *array = &rt_rq->active;
@@ -1179,26 +1210,37 @@ static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
* get throttled and the current group doesn't have any other
* active members.
*/
- if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
+ if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running)) {
+ if (rt_se->on_list)
+ __delist_rt_entity(rt_se, array);
return;
+ }
- if (head)
- list_add(&rt_se->run_list, queue);
- else
- list_add_tail(&rt_se->run_list, queue);
- __set_bit(rt_se_prio(rt_se), array->bitmap);
+ if (move_entity(flags)) {
+ WARN_ON_ONCE(rt_se->on_list);
+ if (flags & ENQUEUE_HEAD)
+ list_add(&rt_se->run_list, queue);
+ else
+ list_add_tail(&rt_se->run_list, queue);
+
+ __set_bit(rt_se_prio(rt_se), array->bitmap);
+ rt_se->on_list = 1;
+ }
+ rt_se->on_rq = 1;
inc_rt_tasks(rt_se, rt_rq);
}
-static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
+static void __dequeue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags)
{
struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
struct rt_prio_array *array = &rt_rq->active;
- list_del_init(&rt_se->run_list);
- if (list_empty(array->queue + rt_se_prio(rt_se)))
- __clear_bit(rt_se_prio(rt_se), array->bitmap);
+ if (move_entity(flags)) {
+ WARN_ON_ONCE(!rt_se->on_list);
+ __delist_rt_entity(rt_se, array);
+ }
+ rt_se->on_rq = 0;
dec_rt_tasks(rt_se, rt_rq);
}
@@ -1207,7 +1249,7 @@ static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
* Because the prio of an upper entry depends on the lower
* entries, we must remove entries top - down.
*/
-static void dequeue_rt_stack(struct sched_rt_entity *rt_se)
+static void dequeue_rt_stack(struct sched_rt_entity *rt_se, unsigned int flags)
{
struct sched_rt_entity *back = NULL;
@@ -1220,31 +1262,31 @@ static void dequeue_rt_stack(struct sched_rt_entity *rt_se)
for (rt_se = back; rt_se; rt_se = rt_se->back) {
if (on_rt_rq(rt_se))
- __dequeue_rt_entity(rt_se);
+ __dequeue_rt_entity(rt_se, flags);
}
}
-static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
+static void enqueue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags)
{
struct rq *rq = rq_of_rt_se(rt_se);
- dequeue_rt_stack(rt_se);
+ dequeue_rt_stack(rt_se, flags);
for_each_sched_rt_entity(rt_se)
- __enqueue_rt_entity(rt_se, head);
+ __enqueue_rt_entity(rt_se, flags);
enqueue_top_rt_rq(&rq->rt);
}
-static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
+static void dequeue_rt_entity(struct sched_rt_entity *rt_se, unsigned int flags)
{
struct rq *rq = rq_of_rt_se(rt_se);
- dequeue_rt_stack(rt_se);
+ dequeue_rt_stack(rt_se, flags);
for_each_sched_rt_entity(rt_se) {
struct rt_rq *rt_rq = group_rt_rq(rt_se);
if (rt_rq && rt_rq->rt_nr_running)
- __enqueue_rt_entity(rt_se, false);
+ __enqueue_rt_entity(rt_se, flags);
}
enqueue_top_rt_rq(&rq->rt);
}
@@ -1260,7 +1302,7 @@ enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
if (flags & ENQUEUE_WAKEUP)
rt_se->timeout = 0;
- enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
+ enqueue_rt_entity(rt_se, flags);
if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
enqueue_pushable_task(rq, p);
@@ -1271,7 +1313,7 @@ static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
struct sched_rt_entity *rt_se = &p->rt;
update_curr_rt(rq);
- dequeue_rt_entity(rt_se);
+ dequeue_rt_entity(rt_se, flags);
dequeue_pushable_task(rq, p);
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index 10f16374df7f..ef5875fff5b7 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -3,6 +3,7 @@
#include <linux/sched/sysctl.h>
#include <linux/sched/rt.h>
#include <linux/sched/deadline.h>
+#include <linux/binfmts.h>
#include <linux/mutex.h>
#include <linux/spinlock.h>
#include <linux/stop_machine.h>
@@ -313,12 +314,11 @@ extern int tg_nop(struct task_group *tg, void *data);
extern void free_fair_sched_group(struct task_group *tg);
extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
-extern void unregister_fair_sched_group(struct task_group *tg, int cpu);
+extern void unregister_fair_sched_group(struct task_group *tg);
extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
struct sched_entity *se, int cpu,
struct sched_entity *parent);
extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
-extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
@@ -909,6 +909,18 @@ static inline unsigned int group_first_cpu(struct sched_group *group)
extern int group_balance_cpu(struct sched_group *sg);
+#if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
+void register_sched_domain_sysctl(void);
+void unregister_sched_domain_sysctl(void);
+#else
+static inline void register_sched_domain_sysctl(void)
+{
+}
+static inline void unregister_sched_domain_sysctl(void)
+{
+}
+#endif
+
#else
static inline void sched_ttwu_pending(void) { }
@@ -1022,6 +1034,7 @@ extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
#endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
extern struct static_key_false sched_numa_balancing;
+extern struct static_key_false sched_schedstats;
static inline u64 global_rt_period(void)
{
@@ -1130,18 +1143,40 @@ static inline void finish_lock_switch(struct rq *rq, struct task_struct *prev)
extern const int sched_prio_to_weight[40];
extern const u32 sched_prio_to_wmult[40];
+/*
+ * {de,en}queue flags:
+ *
+ * DEQUEUE_SLEEP - task is no longer runnable
+ * ENQUEUE_WAKEUP - task just became runnable
+ *
+ * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
+ * are in a known state which allows modification. Such pairs
+ * should preserve as much state as possible.
+ *
+ * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
+ * in the runqueue.
+ *
+ * ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
+ * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
+ * ENQUEUE_WAKING - sched_class::task_waking was called
+ *
+ */
+
+#define DEQUEUE_SLEEP 0x01
+#define DEQUEUE_SAVE 0x02 /* matches ENQUEUE_RESTORE */
+#define DEQUEUE_MOVE 0x04 /* matches ENQUEUE_MOVE */
+
#define ENQUEUE_WAKEUP 0x01
-#define ENQUEUE_HEAD 0x02
+#define ENQUEUE_RESTORE 0x02
+#define ENQUEUE_MOVE 0x04
+
+#define ENQUEUE_HEAD 0x08
+#define ENQUEUE_REPLENISH 0x10
#ifdef CONFIG_SMP
-#define ENQUEUE_WAKING 0x04 /* sched_class::task_waking was called */
+#define ENQUEUE_WAKING 0x20
#else
#define ENQUEUE_WAKING 0x00
#endif
-#define ENQUEUE_REPLENISH 0x08
-#define ENQUEUE_RESTORE 0x10
-
-#define DEQUEUE_SLEEP 0x01
-#define DEQUEUE_SAVE 0x02
#define RETRY_TASK ((void *)-1UL)
diff --git a/kernel/sched/stats.h b/kernel/sched/stats.h
index b0fbc7632de5..70b3b6a20fb0 100644
--- a/kernel/sched/stats.h
+++ b/kernel/sched/stats.h
@@ -29,9 +29,10 @@ rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
if (rq)
rq->rq_sched_info.run_delay += delta;
}
-# define schedstat_inc(rq, field) do { (rq)->field++; } while (0)
-# define schedstat_add(rq, field, amt) do { (rq)->field += (amt); } while (0)
-# define schedstat_set(var, val) do { var = (val); } while (0)
+# define schedstat_enabled() static_branch_unlikely(&sched_schedstats)
+# define schedstat_inc(rq, field) do { if (schedstat_enabled()) { (rq)->field++; } } while (0)
+# define schedstat_add(rq, field, amt) do { if (schedstat_enabled()) { (rq)->field += (amt); } } while (0)
+# define schedstat_set(var, val) do { if (schedstat_enabled()) { var = (val); } } while (0)
#else /* !CONFIG_SCHEDSTATS */
static inline void
rq_sched_info_arrive(struct rq *rq, unsigned long long delta)
@@ -42,6 +43,7 @@ rq_sched_info_dequeued(struct rq *rq, unsigned long long delta)
static inline void
rq_sched_info_depart(struct rq *rq, unsigned long long delta)
{}
+# define schedstat_enabled() 0
# define schedstat_inc(rq, field) do { } while (0)
# define schedstat_add(rq, field, amt) do { } while (0)
# define schedstat_set(var, val) do { } while (0)
diff --git a/kernel/sched/swait.c b/kernel/sched/swait.c
new file mode 100644
index 000000000000..82f0dff90030
--- /dev/null
+++ b/kernel/sched/swait.c
@@ -0,0 +1,123 @@
+#include <linux/sched.h>
+#include <linux/swait.h>
+
+void __init_swait_queue_head(struct swait_queue_head *q, const char *name,
+ struct lock_class_key *key)
+{
+ raw_spin_lock_init(&q->lock);
+ lockdep_set_class_and_name(&q->lock, key, name);
+ INIT_LIST_HEAD(&q->task_list);
+}
+EXPORT_SYMBOL(__init_swait_queue_head);
+
+/*
+ * The thing about the wake_up_state() return value; I think we can ignore it.
+ *
+ * If for some reason it would return 0, that means the previously waiting
+ * task is already running, so it will observe condition true (or has already).
+ */
+void swake_up_locked(struct swait_queue_head *q)
+{
+ struct swait_queue *curr;
+
+ if (list_empty(&q->task_list))
+ return;
+
+ curr = list_first_entry(&q->task_list, typeof(*curr), task_list);
+ wake_up_process(curr->task);
+ list_del_init(&curr->task_list);
+}
+EXPORT_SYMBOL(swake_up_locked);
+
+void swake_up(struct swait_queue_head *q)
+{
+ unsigned long flags;
+
+ if (!swait_active(q))
+ return;
+
+ raw_spin_lock_irqsave(&q->lock, flags);
+ swake_up_locked(q);
+ raw_spin_unlock_irqrestore(&q->lock, flags);
+}
+EXPORT_SYMBOL(swake_up);
+
+/*
+ * Does not allow usage from IRQ disabled, since we must be able to
+ * release IRQs to guarantee bounded hold time.
+ */
+void swake_up_all(struct swait_queue_head *q)
+{
+ struct swait_queue *curr;
+ LIST_HEAD(tmp);
+
+ if (!swait_active(q))
+ return;
+
+ raw_spin_lock_irq(&q->lock);
+ list_splice_init(&q->task_list, &tmp);
+ while (!list_empty(&tmp)) {
+ curr = list_first_entry(&tmp, typeof(*curr), task_list);
+
+ wake_up_state(curr->task, TASK_NORMAL);
+ list_del_init(&curr->task_list);
+
+ if (list_empty(&tmp))
+ break;
+
+ raw_spin_unlock_irq(&q->lock);
+ raw_spin_lock_irq(&q->lock);
+ }
+ raw_spin_unlock_irq(&q->lock);
+}
+EXPORT_SYMBOL(swake_up_all);
+
+void __prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait)
+{
+ wait->task = current;
+ if (list_empty(&wait->task_list))
+ list_add(&wait->task_list, &q->task_list);
+}
+
+void prepare_to_swait(struct swait_queue_head *q, struct swait_queue *wait, int state)
+{
+ unsigned long flags;
+
+ raw_spin_lock_irqsave(&q->lock, flags);
+ __prepare_to_swait(q, wait);
+ set_current_state(state);
+ raw_spin_unlock_irqrestore(&q->lock, flags);
+}
+EXPORT_SYMBOL(prepare_to_swait);
+
+long prepare_to_swait_event(struct swait_queue_head *q, struct swait_queue *wait, int state)
+{
+ if (signal_pending_state(state, current))
+ return -ERESTARTSYS;
+
+ prepare_to_swait(q, wait, state);
+
+ return 0;
+}
+EXPORT_SYMBOL(prepare_to_swait_event);
+
+void __finish_swait(struct swait_queue_head *q, struct swait_queue *wait)
+{
+ __set_current_state(TASK_RUNNING);
+ if (!list_empty(&wait->task_list))
+ list_del_init(&wait->task_list);
+}
+
+void finish_swait(struct swait_queue_head *q, struct swait_queue *wait)
+{
+ unsigned long flags;
+
+ __set_current_state(TASK_RUNNING);
+
+ if (!list_empty_careful(&wait->task_list)) {
+ raw_spin_lock_irqsave(&q->lock, flags);
+ list_del_init(&wait->task_list);
+ raw_spin_unlock_irqrestore(&q->lock, flags);
+ }
+}
+EXPORT_SYMBOL(finish_swait);
diff --git a/kernel/softirq.c b/kernel/softirq.c
index 479e4436f787..8aae49dd7da8 100644
--- a/kernel/softirq.c
+++ b/kernel/softirq.c
@@ -116,9 +116,9 @@ void __local_bh_disable_ip(unsigned long ip, unsigned int cnt)
if (preempt_count() == cnt) {
#ifdef CONFIG_DEBUG_PREEMPT
- current->preempt_disable_ip = get_parent_ip(CALLER_ADDR1);
+ current->preempt_disable_ip = get_lock_parent_ip();
#endif
- trace_preempt_off(CALLER_ADDR0, get_parent_ip(CALLER_ADDR1));
+ trace_preempt_off(CALLER_ADDR0, get_lock_parent_ip());
}
}
EXPORT_SYMBOL(__local_bh_disable_ip);
diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 97715fd9e790..f5102fabef7f 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -350,6 +350,17 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = proc_dointvec,
},
+#ifdef CONFIG_SCHEDSTATS
+ {
+ .procname = "sched_schedstats",
+ .data = NULL,
+ .maxlen = sizeof(unsigned int),
+ .mode = 0644,
+ .proc_handler = sysctl_schedstats,
+ .extra1 = &zero,
+ .extra2 = &one,
+ },
+#endif /* CONFIG_SCHEDSTATS */
#endif /* CONFIG_SMP */
#ifdef CONFIG_NUMA_BALANCING
{
@@ -505,7 +516,7 @@ static struct ctl_table kern_table[] = {
.data = &latencytop_enabled,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec,
+ .proc_handler = sysctl_latencytop,
},
#endif
#ifdef CONFIG_BLK_DEV_INITRD
diff --git a/kernel/tsacct.c b/kernel/tsacct.c
index 975cb49e32bf..f8e26ab963ed 100644
--- a/kernel/tsacct.c
+++ b/kernel/tsacct.c
@@ -93,9 +93,11 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
{
struct mm_struct *mm;
- /* convert pages-usec to Mbyte-usec */
- stats->coremem = p->acct_rss_mem1 * PAGE_SIZE / MB;
- stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE / MB;
+ /* convert pages-nsec/1024 to Mbyte-usec, see __acct_update_integrals */
+ stats->coremem = p->acct_rss_mem1 * PAGE_SIZE;
+ do_div(stats->coremem, 1000 * KB);
+ stats->virtmem = p->acct_vm_mem1 * PAGE_SIZE;
+ do_div(stats->virtmem, 1000 * KB);
mm = get_task_mm(p);
if (mm) {
/* adjust to KB unit */
@@ -123,27 +125,28 @@ void xacct_add_tsk(struct taskstats *stats, struct task_struct *p)
static void __acct_update_integrals(struct task_struct *tsk,
cputime_t utime, cputime_t stime)
{
- if (likely(tsk->mm)) {
- cputime_t time, dtime;
- struct timeval value;
- unsigned long flags;
- u64 delta;
-
- local_irq_save(flags);
- time = stime + utime;
- dtime = time - tsk->acct_timexpd;
- jiffies_to_timeval(cputime_to_jiffies(dtime), &value);
- delta = value.tv_sec;
- delta = delta * USEC_PER_SEC + value.tv_usec;
-
- if (delta == 0)
- goto out;
- tsk->acct_timexpd = time;
- tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm);
- tsk->acct_vm_mem1 += delta * tsk->mm->total_vm;
- out:
- local_irq_restore(flags);
- }
+ cputime_t time, dtime;
+ u64 delta;
+
+ if (!likely(tsk->mm))
+ return;
+
+ time = stime + utime;
+ dtime = time - tsk->acct_timexpd;
+ /* Avoid division: cputime_t is often in nanoseconds already. */
+ delta = cputime_to_nsecs(dtime);
+
+ if (delta < TICK_NSEC)
+ return;
+
+ tsk->acct_timexpd = time;
+ /*
+ * Divide by 1024 to avoid overflow, and to avoid division.
+ * The final unit reported to userspace is Mbyte-usecs,
+ * the rest of the math is done in xacct_add_tsk.
+ */
+ tsk->acct_rss_mem1 += delta * get_mm_rss(tsk->mm) >> 10;
+ tsk->acct_vm_mem1 += delta * tsk->mm->total_vm >> 10;
}
/**
@@ -153,9 +156,12 @@ static void __acct_update_integrals(struct task_struct *tsk,
void acct_update_integrals(struct task_struct *tsk)
{
cputime_t utime, stime;
+ unsigned long flags;
+ local_irq_save(flags);
task_cputime(tsk, &utime, &stime);
__acct_update_integrals(tsk, utime, stime);
+ local_irq_restore(flags);
}
/**
diff --git a/virt/kvm/async_pf.c b/virt/kvm/async_pf.c
index db2dd3335c6a..65da997b430a 100644
--- a/virt/kvm/async_pf.c
+++ b/virt/kvm/async_pf.c
@@ -97,8 +97,8 @@ static void async_pf_execute(struct work_struct *work)
* This memory barrier pairs with prepare_to_wait's set_current_state()
*/
smp_mb();
- if (waitqueue_active(&vcpu->wq))
- wake_up_interruptible(&vcpu->wq);
+ if (swait_active(&vcpu->wq))
+ swake_up(&vcpu->wq);
mmput(mm);
kvm_put_kvm(vcpu->kvm);
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index a11cfd20a6a0..f8417d09a56d 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -216,8 +216,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
vcpu->kvm = kvm;
vcpu->vcpu_id = id;
vcpu->pid = NULL;
- vcpu->halt_poll_ns = 0;
- init_waitqueue_head(&vcpu->wq);
+ init_swait_queue_head(&vcpu->wq);
kvm_async_pf_vcpu_init(vcpu);
vcpu->pre_pcpu = -1;
@@ -1990,7 +1989,7 @@ static int kvm_vcpu_check_block(struct kvm_vcpu *vcpu)
void kvm_vcpu_block(struct kvm_vcpu *vcpu)
{
ktime_t start, cur;
- DEFINE_WAIT(wait);
+ DECLARE_SWAITQUEUE(wait);
bool waited = false;
u64 block_ns;
@@ -2015,7 +2014,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
kvm_arch_vcpu_blocking(vcpu);
for (;;) {
- prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
+ prepare_to_swait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE);
if (kvm_vcpu_check_block(vcpu) < 0)
break;
@@ -2024,7 +2023,7 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu)
schedule();
}
- finish_wait(&vcpu->wq, &wait);
+ finish_swait(&vcpu->wq, &wait);
cur = ktime_get();
kvm_arch_vcpu_unblocking(vcpu);
@@ -2056,11 +2055,11 @@ void kvm_vcpu_kick(struct kvm_vcpu *vcpu)
{
int me;
int cpu = vcpu->cpu;
- wait_queue_head_t *wqp;
+ struct swait_queue_head *wqp;
wqp = kvm_arch_vcpu_wq(vcpu);
- if (waitqueue_active(wqp)) {
- wake_up_interruptible(wqp);
+ if (swait_active(wqp)) {
+ swake_up(wqp);
++vcpu->stat.halt_wakeup;
}
@@ -2161,7 +2160,7 @@ void kvm_vcpu_on_spin(struct kvm_vcpu *me)
continue;
if (vcpu == me)
continue;
- if (waitqueue_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
+ if (swait_active(&vcpu->wq) && !kvm_arch_vcpu_runnable(vcpu))
continue;
if (!kvm_vcpu_eligible_for_directed_yield(vcpu))
continue;
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