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Merge branch 'perf/urgent' of git://git.kernel.org/pub/scm/linux/kernel/git/frederic/random-tracing into perf/core

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This commit is contained in:
Ingo Molnar
2010-05-20 14:38:55 +02:00
parent f869097e88 85cb68b27c
commit dfacc4d6c9
551 changed files with 11391 additions and 7782 deletions
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58
kernel/perf_event.c
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@@ -4050,19 +4050,46 @@ static inline u64 swevent_hash(u64 type, u32 event_id)
return hash_64(val, SWEVENT_HLIST_BITS);
}
static struct hlist_head *
find_swevent_head(struct perf_cpu_context *ctx, u64 type, u32 event_id)
static inline struct hlist_head *
__find_swevent_head(struct swevent_hlist *hlist, u64 type, u32 event_id)
{
u64 hash;
struct swevent_hlist *hlist;
u64 hash = swevent_hash(type, event_id);
hash = swevent_hash(type, event_id);
return &hlist->heads[hash];
}
/* For the read side: events when they trigger */
static inline struct hlist_head *
find_swevent_head_rcu(struct perf_cpu_context *ctx, u64 type, u32 event_id)
{
struct swevent_hlist *hlist;
hlist = rcu_dereference(ctx->swevent_hlist);
if (!hlist)
return NULL;
return &hlist->heads[hash];
return __find_swevent_head(hlist, type, event_id);
}
/* For the event head insertion and removal in the hlist */
static inline struct hlist_head *
find_swevent_head(struct perf_cpu_context *ctx, struct perf_event *event)
{
struct swevent_hlist *hlist;
u32 event_id = event->attr.config;
u64 type = event->attr.type;
/*
* Event scheduling is always serialized against hlist allocation
* and release. Which makes the protected version suitable here.
* The context lock guarantees that.
*/
hlist = rcu_dereference_protected(ctx->swevent_hlist,
lockdep_is_held(&event->ctx->lock));
if (!hlist)
return NULL;
return __find_swevent_head(hlist, type, event_id);
}
static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
@@ -4079,7 +4106,7 @@ static void do_perf_sw_event(enum perf_type_id type, u32 event_id,
rcu_read_lock();
head = find_swevent_head(cpuctx, type, event_id);
head = find_swevent_head_rcu(cpuctx, type, event_id);
if (!head)
goto end;
@@ -4162,7 +4189,7 @@ static int perf_swevent_enable(struct perf_event *event)
perf_swevent_set_period(event);
}
head = find_swevent_head(cpuctx, event->attr.type, event->attr.config);
head = find_swevent_head(cpuctx, event);
if (WARN_ON_ONCE(!head))
return -EINVAL;
@@ -4350,6 +4377,14 @@ static const struct pmu perf_ops_task_clock = {
.read = task_clock_perf_event_read,
};
/* Deref the hlist from the update side */
static inline struct swevent_hlist *
swevent_hlist_deref(struct perf_cpu_context *cpuctx)
{
return rcu_dereference_protected(cpuctx->swevent_hlist,
lockdep_is_held(&cpuctx->hlist_mutex));
}
static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
{
struct swevent_hlist *hlist;
@@ -4360,12 +4395,11 @@ static void swevent_hlist_release_rcu(struct rcu_head *rcu_head)
static void swevent_hlist_release(struct perf_cpu_context *cpuctx)
{
struct swevent_hlist *hlist;
struct swevent_hlist *hlist = swevent_hlist_deref(cpuctx);
if (!cpuctx->swevent_hlist)
if (!hlist)
return;
hlist = cpuctx->swevent_hlist;
rcu_assign_pointer(cpuctx->swevent_hlist, NULL);
call_rcu(&hlist->rcu_head, swevent_hlist_release_rcu);
}
@@ -4402,7 +4436,7 @@ static int swevent_hlist_get_cpu(struct perf_event *event, int cpu)
mutex_lock(&cpuctx->hlist_mutex);
if (!cpuctx->swevent_hlist && cpu_online(cpu)) {
if (!swevent_hlist_deref(cpuctx) && cpu_online(cpu)) {
struct swevent_hlist *hlist;
hlist = kzalloc(sizeof(*hlist), GFP_KERNEL);