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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-25 17:53:09 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-25 17:53:09 -0700
commit2a20b02c055a14eb60ac8da737d79dc940bb9ee0 (patch)
tree1cf09a5e13f8ed24bc66386c153969ad49f8f098 /kernel/perf_event.c
parent839767e79e7bdf06f241a47701f0f64b8e2d3f61 (diff)
parent45daae575e08bbf7405c5a3633e956fa364d1b4f (diff)
Merge branch 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perf-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf, x86: Complain louder about BIOSen corrupting CPU/PMU state and continue perf, x86: P4 PMU - Read proper MSR register to catch unflagged overflows perf symbols: Look at .dynsym again if .symtab not found perf build-id: Add quirk to deal with perf.data file format breakage perf session: Pass evsel in event_ops->sample() perf: Better fit max unprivileged mlock pages for tools needs perf_events: Fix stale ->cgrp pointer in update_cgrp_time_from_cpuctx() perf top: Fix uninitialized 'counter' variable tracing: Fix set_ftrace_filter probe function display perf, x86: Fix Intel fixed counters base initialization
Diffstat (limited to 'kernel/perf_event.c')
-rw-r--r--kernel/perf_event.c15
1 files changed, 13 insertions, 2 deletions
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index 3472bb1a070c..c75925c4d1e2 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -145,7 +145,8 @@ static struct srcu_struct pmus_srcu;
*/
int sysctl_perf_event_paranoid __read_mostly = 1;
-int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */
+/* Minimum for 128 pages + 1 for the user control page */
+int sysctl_perf_event_mlock __read_mostly = 516; /* 'free' kb per user */
/*
* max perf event sample rate
@@ -941,6 +942,7 @@ static void perf_group_attach(struct perf_event *event)
static void
list_del_event(struct perf_event *event, struct perf_event_context *ctx)
{
+ struct perf_cpu_context *cpuctx;
/*
* We can have double detach due to exit/hot-unplug + close.
*/
@@ -949,8 +951,17 @@ list_del_event(struct perf_event *event, struct perf_event_context *ctx)
event->attach_state &= ~PERF_ATTACH_CONTEXT;
- if (is_cgroup_event(event))
+ if (is_cgroup_event(event)) {
ctx->nr_cgroups--;
+ cpuctx = __get_cpu_context(ctx);
+ /*
+ * if there are no more cgroup events
+ * then cler cgrp to avoid stale pointer
+ * in update_cgrp_time_from_cpuctx()
+ */
+ if (!ctx->nr_cgroups)
+ cpuctx->cgrp = NULL;
+ }
ctx->nr_events--;
if (event->attr.inherit_stat)