ich777/linux_media
1
0
Fork 0
mirror of https://github.com/tbsdtv/linux_media.git synced 2025-07-23 04:33:26 +02:00
Code Issues Packages Projects Releases Wiki Activity

perf: Re-instate the linear PMU search

Browse Source 
Full revert of commit 9551fbb64d ("perf/core: Remove pmu linear
searching code").

Some architectures (notably arm/arm64) still relied on the linear
search in order to find the PMU that consumes
PERF_TYPE_{HARDWARE,HW_CACHE,RAW}.

This will need a more thorought audit and cleanup.

Reported-by: Nathan Chancellor <nathan@kernel.org>
Reported-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230605101401.GL38236@hirez.programming.kicks-ass.net
This commit is contained in:
Peter Zijlstra
2023-06-05 12:14:01 +02:00
parent 10d95a317e
commit 228020b490
1 changed files with 24 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

37
kernel/events/core.c
View File

@@ -11630,27 +11630,38 @@ static struct pmu *perf_init_event(struct perf_event *event)
}
again:
ret = -ENOENT;
rcu_read_lock();
pmu = idr_find(&pmu_idr, type);
rcu_read_unlock();
if (!pmu)
goto fail;
if (pmu) {
if (event->attr.type != type && type != PERF_TYPE_RAW &&
!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE))
goto fail;
if (event->attr.type != type && type != PERF_TYPE_RAW &&
!(pmu->capabilities & PERF_PMU_CAP_EXTENDED_HW_TYPE))
goto fail;
ret = perf_try_init_event(pmu, event);
if (ret == -ENOENT && event->attr.type != type && !extended_type) {
type = event->attr.type;
goto again;
}
ret = perf_try_init_event(pmu, event);
if (ret == -ENOENT && event->attr.type != type && !extended_type) {
type = event->attr.type;
goto again;
if (ret)
pmu = ERR_PTR(ret);
goto unlock;
}
fail:
if (ret)
pmu = ERR_PTR(ret);
list_for_each_entry_rcu(pmu, &pmus, entry, lockdep_is_held(&pmus_srcu)) {
ret = perf_try_init_event(pmu, event);
if (!ret)
goto unlock;
if (ret != -ENOENT) {
pmu = ERR_PTR(ret);
goto unlock;
}
}
fail:
pmu = ERR_PTR(-ENOENT);
unlock:
srcu_read_unlock(&pmus_srcu, idx);