[GIT PULL] perf fixes

From: Ingo Molnar
Date: Sat Nov 16 2019 - 16:33:41 EST


Linus,

Please pull the latest perf-urgent-for-linus git tree from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus

# HEAD: d00dbd29814236ad128ff9517e8f7af6b6ef4ba0 perf/core: Fix missing static inline on perf_cgroup_switch()

Misc fixes: a handful of AUX event handling related fixes, a Sparse fix
and two ABI fixes.

Thanks,

Ingo

------------------>
Alexander Shishkin (4):
perf/aux: Fix the aux_output group inheritance fix
perf/core: Reattach a misplaced comment
perf/aux: Disallow aux_output for kernel events
perf/core: Consistently fail fork on allocation failures

Ben Dooks (Codethink) (1):
perf/core: Fix missing static inline on perf_cgroup_switch()

Peter Zijlstra (1):
perf/core: Disallow uncore-cgroup events


kernel/events/core.c | 23 +++++++++++++++++++----
1 file changed, 19 insertions(+), 4 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index aec8dba2bea4..00a014670ed0 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1031,7 +1031,7 @@ perf_cgroup_set_timestamp(struct task_struct *task,
{
}

-void
+static inline void
perf_cgroup_switch(struct task_struct *task, struct task_struct *next)
{
}
@@ -10535,6 +10535,15 @@ perf_event_alloc(struct perf_event_attr *attr, int cpu,
goto err_ns;
}

+ /*
+ * Disallow uncore-cgroup events, they don't make sense as the cgroup will
+ * be different on other CPUs in the uncore mask.
+ */
+ if (pmu->task_ctx_nr == perf_invalid_context && cgroup_fd != -1) {
+ err = -EINVAL;
+ goto err_pmu;
+ }
+
if (event->attr.aux_output &&
!(pmu->capabilities & PERF_PMU_CAP_AUX_OUTPUT)) {
err = -EOPNOTSUPP;
@@ -11323,8 +11332,11 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
int err;

/*
- * Get the target context (task or percpu):
+ * Grouping is not supported for kernel events, neither is 'AUX',
+ * make sure the caller's intentions are adjusted.
*/
+ if (attr->aux_output)
+ return ERR_PTR(-EINVAL);

event = perf_event_alloc(attr, cpu, task, NULL, NULL,
overflow_handler, context, -1);
@@ -11336,6 +11348,9 @@ perf_event_create_kernel_counter(struct perf_event_attr *attr, int cpu,
/* Mark owner so we could distinguish it from user events. */
event->owner = TASK_TOMBSTONE;

+ /*
+ * Get the target context (task or percpu):
+ */
ctx = find_get_context(event->pmu, task, event);
if (IS_ERR(ctx)) {
err = PTR_ERR(ctx);
@@ -11787,7 +11802,7 @@ inherit_event(struct perf_event *parent_event,
GFP_KERNEL);
if (!child_ctx->task_ctx_data) {
free_event(child_event);
- return NULL;
+ return ERR_PTR(-ENOMEM);
}
}

@@ -11890,7 +11905,7 @@ static int inherit_group(struct perf_event *parent_event,
if (IS_ERR(child_ctr))
return PTR_ERR(child_ctr);

- if (sub->aux_event == parent_event &&
+ if (sub->aux_event == parent_event && child_ctr &&
!perf_get_aux_event(child_ctr, leader))
return -EINVAL;
}