Commit Graph

6 Commits

Author SHA1 Message Date
Xiaomeng Tong
cbe2c84804 perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator
commit 2012a9e279013933885983cbe0a5fe828052563b upstream.

The bug is here:
	return cluster;

The list iterator value 'cluster' will *always* be set and non-NULL
by list_for_each_entry(), so it is incorrect to assume that the
iterator value will be NULL if the list is empty or no element
is found.

To fix the bug, return 'cluster' when found, otherwise return NULL.

Cc: stable@vger.kernel.org
Fixes: 21bdbb7102 ("perf: add qcom l2 cache perf events driver")
Signed-off-by: Xiaomeng Tong <xiam0nd.tong@gmail.com>
Link: https://lore.kernel.org/r/20220327055733.4070-1-xiam0nd.tong@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-15 14:15:06 +02:00
Peter Zijlstra
edb39592a5 perf: Fix sibling iteration
Mark noticed that the change to sibling_list changed some iteration
semantics; because previously we used group_list as list entry,
sibling events would always have an empty sibling_list.

But because we now use sibling_list for both list head and list entry,
siblings will report as having siblings.

Fix this with a custom for_each_sibling_event() iterator.

Fixes: 8343aae661 ("perf/core: Remove perf_event::group_entry")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Suggested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: vincent.weaver@maine.edu
Cc: alexander.shishkin@linux.intel.com
Cc: torvalds@linux-foundation.org
Cc: alexey.budankov@linux.intel.com
Cc: valery.cherepennikov@intel.com
Cc: eranian@google.com
Cc: acme@redhat.com
Cc: linux-tip-commits@vger.kernel.org
Cc: davidcc@google.com
Cc: kan.liang@intel.com
Cc: Dmitry.Prohorov@intel.com
Cc: jolsa@redhat.com
Link: https://lkml.kernel.org/r/20180315170129.GX4043@hirez.programming.kicks-ass.net
2018-03-16 20:44:12 +01:00
Peter Zijlstra
8343aae661 perf/core: Remove perf_event::group_entry
Now that all the grouping is done with RB trees, we no longer need
group_entry and can replace the whole thing with sibling_list.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Carrillo-Cisneros <davidcc@google.com>
Cc: Dmitri Prokhorov <Dmitry.Prohorov@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Valery Cherepennikov <valery.cherepennikov@intel.com>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-03-12 15:28:49 +01:00
Neil Leeder
b65423ed46 perf: qcom_l2_pmu: add event names
Add event names so that common events can be
specified symbolically, for example:

l2cache_0/total-reads/,l2cache_0/cycles/

Event names are displayed in 'perf list'.

Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-02 10:13:06 +01:00
Neil Leeder
6c17c1c309 perf: qcom_l2: fix column exclusion check
The check for column exclusion did not verify that the event being
checked was an L2 event, and not a software event.
Software events should not be checked for column exclusion.
This resulted in a group with both software and L2 events sometimes
incorrectly rejecting the L2 event for column exclusion and
not counting it.

Add a check for PMU type before applying column exclusion logic.

Fixes: 21bdbb7102 ("perf: add qcom l2 cache perf events driver")
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-07-26 09:27:43 +01:00
Neil Leeder
21bdbb7102 perf: add qcom l2 cache perf events driver
Adds perf events support for L2 cache PMU.

The L2 cache PMU driver is named 'l2cache_0' and can be used
with perf events to profile L2 events such as cache hits
and misses on Qualcomm Technologies processors.

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
[will: minimise nesting in l2_cache_associate_cpu_with_cluster]
[will: use kstrtoul for unsigned long, remove redunant .owner setting]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-08 19:32:24 +00:00