path: root/arch/arm/kernel/perf_event.c
diff options
authorWill Deacon <will.deacon@arm.com>2011-11-17 15:05:14 +0000
committerWill Deacon <will.deacon@arm.com>2011-11-17 15:20:03 +0000
commitbce34d14428d35d9a06ddc10cd46ecef311764c9 (patch)
tree231aafe3e3b35f7b00da16240fa5a6b8ecdf2870 /arch/arm/kernel/perf_event.c
parent14e25c5eeb90d4f61cc94933307d04a19738ad2f (diff)
ARM: perf: initialise used_mask for fake PMU during validation
When validating an event group, we call pmu->get_event_idx for each group member in order to check that the group can be scheduled as a unit on an empty PMU. As a result of 3fc2c830 ("ARM: perf: remove event limit from pmu_hw_events"), the used_mask member of struct cpu_hw_events must be setup explicitly, something which we don't do for the fake cpu_hw_events used for validation. This patch sets up an empty used_mask for the fake validation cpu_hw_events, preventing NULL deferences when trying to get the event index. Reported-by: Pawel Moll <pawel.moll@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm/kernel/perf_event.c')
1 files changed, 7 insertions, 1 deletions
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 24e2347be6b..e508066d3d6 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -343,8 +343,14 @@ validate_group(struct perf_event *event)
struct perf_event *sibling, *leader = event->group_leader;
struct pmu_hw_events fake_pmu;
- memset(&fake_pmu, 0, sizeof(fake_pmu));
+ /*
+ * Initialise the fake PMU. We only need to populate the
+ * used_mask for the purposes of validation.
+ */
+ memset(fake_used_mask, 0, sizeof(fake_used_mask));
+ fake_pmu.used_mask = fake_used_mask;
if (!validate_event(&fake_pmu, leader))
return -ENOSPC;