linux-kernel - [PATCH v2 1/2] perf/core: add perf_ctx

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

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon,  8 Apr 2019 10:32:51 -0700
From:   Stephane Eranian <eranian@...gle.com>
To:     linux-kernel@...r.kernel.org
Cc:     peterz@...radead.org, tglx@...utronix.de, ak@...ux.intel.com,
        kan.liang@...el.com, mingo@...e.hu, nelson.dsouza@...el.com,
        jolsa@...hat.com, tonyj@...e.com
Subject: [PATCH v2 1/2] perf/core: add perf_ctx_resched() as global function

This patch add perf_ctx_resched() a global function that can be called
to force rescheduling of events based on event types. The function locks
both cpuctx and task_ctx internally. This will be used by a subsequent patch.

Signed-off-by: Stephane Eranian <eranian@...gle.com>
Change-Id: Icbc05e5f461fd6e091b46778fe62b23f308e2be7
---
 include/linux/perf_event.h | 14 ++++++++++++++
 kernel/events/core.c       | 18 +++++++++---------
 2 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 085a95e2582a..ee8a275df0ed 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -822,6 +822,15 @@ struct bpf_perf_event_data_kern {
 	struct perf_event *event;
 };
 
+enum event_type_t {
+	EVENT_FLEXIBLE = 0x1,
+	EVENT_PINNED = 0x2,
+	EVENT_TIME = 0x4,
+	/* see ctx_resched() for details */
+	EVENT_CPU = 0x8,
+	EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED,
+};
+
 #ifdef CONFIG_CGROUP_PERF
 
 /*
@@ -888,6 +897,11 @@ extern void perf_sched_cb_dec(struct pmu *pmu);
 extern void perf_sched_cb_inc(struct pmu *pmu);
 extern int perf_event_task_disable(void);
 extern int perf_event_task_enable(void);
+
+extern void perf_ctx_resched(struct perf_cpu_context *cpuctx,
+			     struct perf_event_context *task_ctx,
+			     enum event_type_t event_type);
+
 extern int perf_event_refresh(struct perf_event *event, int refresh);
 extern void perf_event_update_userpage(struct perf_event *event);
 extern int perf_event_release_kernel(struct perf_event *event);
diff --git a/kernel/events/core.c b/kernel/events/core.c
index dfc4bab0b02b..30474064ec22 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -354,15 +354,6 @@ static void event_function_local(struct perf_event *event, event_f func, void *d
 	(PERF_SAMPLE_BRANCH_KERNEL |\
 	 PERF_SAMPLE_BRANCH_HV)
 
-enum event_type_t {
-	EVENT_FLEXIBLE = 0x1,
-	EVENT_PINNED = 0x2,
-	EVENT_TIME = 0x4,
-	/* see ctx_resched() for details */
-	EVENT_CPU = 0x8,
-	EVENT_ALL = EVENT_FLEXIBLE | EVENT_PINNED,
-};
-
 /*
  * perf_sched_events : >0 events exist
  * perf_cgroup_events: >0 per-cpu cgroup events exist on this cpu
@@ -2477,6 +2468,15 @@ static void ctx_resched(struct perf_cpu_context *cpuctx,
 	perf_pmu_enable(cpuctx->ctx.pmu);
 }
 
+void perf_ctx_resched(struct perf_cpu_context *cpuctx,
+		      struct perf_event_context *task_ctx,
+		      enum event_type_t event_type)
+{
+	perf_ctx_lock(cpuctx, task_ctx);
+	ctx_resched(cpuctx, task_ctx, event_type);
+	perf_ctx_unlock(cpuctx, task_ctx);
+}
+
 /*
  * Cross CPU call to install and enable a performance event
  *
-- 
2.21.0.392.gf8f6787159e-goog