perf: Move cgroup init before PMU ->event_init()
The Intel QoS PMU needs to know whether an event is part of a cgroup
during ->event_init(), because tasks in the same cgroup share a
monitoring ID.
Move the cgroup initialisation before calling into the PMU driver.
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kanaka Juvva <kanaka.d.juvva@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Vikas Shivappa <vikas.shivappa@linux.intel.com>
Link: http://lkml.kernel.org/r/1422038748-21397-4-git-send-email-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 4e8dc59..1fc3bae 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -7116,7 +7116,7 @@
struct perf_event *group_leader,
struct perf_event *parent_event,
perf_overflow_handler_t overflow_handler,
- void *context)
+ void *context, int cgroup_fd)
{
struct pmu *pmu;
struct perf_event *event;
@@ -7212,6 +7212,12 @@
if (!has_branch_stack(event))
event->attr.branch_sample_type = 0;
+ if (cgroup_fd != -1) {
+ err = perf_cgroup_connect(cgroup_fd, event, attr, group_leader);
+ if (err)
+ goto err_ns;
+ }
+
pmu = perf_init_event(event);
if (!pmu)
goto err_ns;
@@ -7235,6 +7241,8 @@
event->destroy(event);
module_put(pmu->module);
err_ns:
+ if (is_cgroup_event(event))
+ perf_detach_cgroup(event);
if (event->ns)
put_pid_ns(event->ns);
kfree(event);
@@ -7453,6 +7461,7 @@
int move_group = 0;
int err;
int f_flags = O_RDWR;
+ int cgroup_fd = -1;
/* for future expandability... */
if (flags & ~PERF_FLAG_ALL)
@@ -7518,21 +7527,16 @@
get_online_cpus();
+ if (flags & PERF_FLAG_PID_CGROUP)
+ cgroup_fd = pid;
+
event = perf_event_alloc(&attr, cpu, task, group_leader, NULL,
- NULL, NULL);
+ NULL, NULL, cgroup_fd);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err_cpus;
}
- if (flags & PERF_FLAG_PID_CGROUP) {
- err = perf_cgroup_connect(pid, event, &attr, group_leader);
- if (err) {
- __free_event(event);
- goto err_cpus;
- }
- }
-
if (is_sampling_event(event)) {
if (event->pmu->capabilities & PERF_PMU_CAP_NO_INTERRUPT) {
err = -ENOTSUPP;
@@ -7769,7 +7773,7 @@
*/
event = perf_event_alloc(attr, cpu, task, NULL, NULL,
- overflow_handler, context);
+ overflow_handler, context, -1);
if (IS_ERR(event)) {
err = PTR_ERR(event);
goto err;
@@ -8130,7 +8134,7 @@
parent_event->cpu,
child,
group_leader, parent_event,
- NULL, NULL);
+ NULL, NULL, -1);
if (IS_ERR(child_event))
return child_event;
