| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Thu, 31 Jan 2013 23:11:33 -0500
From: Len Brown <lenb@...nel.org>
To: linux-pm@...r.kernel.org
Cc: linux-kernel@...r.kernel.org, Len Brown <len.brown@...el.com>
Subject: [PATCH 1/4] intel_idle: stop using driver_data for static flags
From: Len Brown <len.brown@...el.com>
The commit, 4202735e8ab6ecfb0381631a0d0b58fefe0bd4e2
(cpuidle: Split cpuidle_state structure and move per-cpu statistics fields)
observed that the MWAIT flags for Cn on every processor to date were the
same, and created get_driver_data() to supply them.
Unfortunately, that assumption is false, going forward.
So here we restore the MWAIT flags to the cpuidle_state table.
However, instead restoring the old "driver_data" field,
we put the flags into the existing "flags" field,
where they probalby should have lived all along.
This patch does not change any operation.
This patch removes 1 of the 3 users of cpuidle_state_usage.driver_data.
Perhaps some day we'll get rid of the other 2.
Signed-off-by: Len Brown <len.brown@...el.com>
---
drivers/idle/intel_idle.c | 75 ++++++++++++++++-------------------------------
1 file changed, 26 insertions(+), 49 deletions(-)
diff --git a/drivers/idle/intel_idle.c b/drivers/idle/intel_idle.c
index 2df9414..8331753 100644
--- a/drivers/idle/intel_idle.c
+++ b/drivers/idle/intel_idle.c
@@ -109,6 +109,16 @@ static struct cpuidle_state *cpuidle_state_table;
#define CPUIDLE_FLAG_TLB_FLUSHED 0x10000
/*
+ * MWAIT takes an 8-bit "hint" in EAX "suggesting"
+ * the C-state (top nibble) and sub-state (bottom nibble)
+ * 0x00 means "MWAIT(C1)", 0x10 means "MWAIT(C2)" etc.
+ *
+ * We store the hint at the top of our "flags" for each state.
+ */
+#define flags_2_MWAIT_EAX(flags) (((flags) >> 24) & 0xFF)
+#define MWAIT_EAX_2_flags(eax) ((eax & 0xFF) << 24)
+
+/*
* States are indexed by the cstate number,
* which is also the index into the MWAIT hint array.
* Thus C0 is a dummy.
@@ -118,21 +128,21 @@ static struct cpuidle_state nehalem_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C1 */
.name = "C1-NHM",
.desc = "MWAIT 0x00",
- .flags = CPUIDLE_FLAG_TIME_VALID,
+ .flags = MWAIT_EAX_2_flags(0x00) | CPUIDLE_FLAG_TIME_VALID,
.exit_latency = 3,
.target_residency = 6,
.enter = &intel_idle },
{ /* MWAIT C2 */
.name = "C3-NHM",
.desc = "MWAIT 0x10",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x10) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 20,
.target_residency = 80,
.enter = &intel_idle },
{ /* MWAIT C3 */
.name = "C6-NHM",
.desc = "MWAIT 0x20",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x20) |CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 200,
.target_residency = 800,
.enter = &intel_idle },
@@ -143,28 +153,28 @@ static struct cpuidle_state snb_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C1 */
.name = "C1-SNB",
.desc = "MWAIT 0x00",
- .flags = CPUIDLE_FLAG_TIME_VALID,
+ .flags = MWAIT_EAX_2_flags(0x00) | CPUIDLE_FLAG_TIME_VALID,
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle },
{ /* MWAIT C2 */
.name = "C3-SNB",
.desc = "MWAIT 0x10",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x10) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 80,
.target_residency = 211,
.enter = &intel_idle },
{ /* MWAIT C3 */
.name = "C6-SNB",
.desc = "MWAIT 0x20",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x20) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 104,
.target_residency = 345,
.enter = &intel_idle },
{ /* MWAIT C4 */
.name = "C7-SNB",
.desc = "MWAIT 0x30",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x30) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 109,
.target_residency = 345,
.enter = &intel_idle },
@@ -175,28 +185,28 @@ static struct cpuidle_state ivb_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C1 */
.name = "C1-IVB",
.desc = "MWAIT 0x00",
- .flags = CPUIDLE_FLAG_TIME_VALID,
+ .flags = MWAIT_EAX_2_flags(0x00) | CPUIDLE_FLAG_TIME_VALID,
.exit_latency = 1,
.target_residency = 1,
.enter = &intel_idle },
{ /* MWAIT C2 */
.name = "C3-IVB",
.desc = "MWAIT 0x10",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x10) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 59,
.target_residency = 156,
.enter = &intel_idle },
{ /* MWAIT C3 */
.name = "C6-IVB",
.desc = "MWAIT 0x20",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x20) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 80,
.target_residency = 300,
.enter = &intel_idle },
{ /* MWAIT C4 */
.name = "C7-IVB",
.desc = "MWAIT 0x30",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x30) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 87,
.target_residency = 300,
.enter = &intel_idle },
@@ -207,14 +217,14 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C1 */
.name = "C1-ATM",
.desc = "MWAIT 0x00",
- .flags = CPUIDLE_FLAG_TIME_VALID,
+ .flags = MWAIT_EAX_2_flags(0x00) | CPUIDLE_FLAG_TIME_VALID,
.exit_latency = 1,
.target_residency = 4,
.enter = &intel_idle },
{ /* MWAIT C2 */
.name = "C2-ATM",
.desc = "MWAIT 0x10",
- .flags = CPUIDLE_FLAG_TIME_VALID,
+ .flags = MWAIT_EAX_2_flags(0x10) | CPUIDLE_FLAG_TIME_VALID,
.exit_latency = 20,
.target_residency = 80,
.enter = &intel_idle },
@@ -222,7 +232,7 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C4 */
.name = "C4-ATM",
.desc = "MWAIT 0x30",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x30) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 100,
.target_residency = 400,
.enter = &intel_idle },
@@ -230,41 +240,12 @@ static struct cpuidle_state atom_cstates[MWAIT_MAX_NUM_CSTATES] = {
{ /* MWAIT C6 */
.name = "C6-ATM",
.desc = "MWAIT 0x52",
- .flags = CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
+ .flags = MWAIT_EAX_2_flags(0x52) | CPUIDLE_FLAG_TIME_VALID | CPUIDLE_FLAG_TLB_FLUSHED,
.exit_latency = 140,
.target_residency = 560,
.enter = &intel_idle },
};
-static long get_driver_data(int cstate)
-{
- int driver_data;
- switch (cstate) {
-
- case 1: /* MWAIT C1 */
- driver_data = 0x00;
- break;
- case 2: /* MWAIT C2 */
- driver_data = 0x10;
- break;
- case 3: /* MWAIT C3 */
- driver_data = 0x20;
- break;
- case 4: /* MWAIT C4 */
- driver_data = 0x30;
- break;
- case 5: /* MWAIT C5 */
- driver_data = 0x40;
- break;
- case 6: /* MWAIT C6 */
- driver_data = 0x52;
- break;
- default:
- driver_data = 0x00;
- }
- return driver_data;
-}
-
/**
* intel_idle
* @dev: cpuidle_device
@@ -278,8 +259,7 @@ static int intel_idle(struct cpuidle_device *dev,
{
unsigned long ecx = 1; /* break on interrupt flag */
struct cpuidle_state *state = &drv->states[index];
- struct cpuidle_state_usage *state_usage = &dev->states_usage[index];
- unsigned long eax = (unsigned long)cpuidle_get_statedata(state_usage);
+ unsigned long eax = flags_2_MWAIT_EAX(state->flags);
unsigned int cstate;
int cpu = smp_processor_id();
@@ -558,9 +538,6 @@ static int intel_idle_cpu_init(int cpu)
if (cpuidle_state_table[cstate].enter == NULL)
continue;
- dev->states_usage[dev->state_count].driver_data =
- (void *)get_driver_data(cstate);
-
dev->state_count += 1;
}
--
1.8.1.2.422.g08c0e7f
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists