perf/smmuv3: Validate groups for global filtering

With global filtering, it becomes possible for users to construct
self-contradictory groups with conflicting filters. Make sure we
cover that when initially validating events.

Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Robin Murphy 2019-08-01 16:22:45 +01:00 committed by Will Deacon
parent 33e84ea433
commit 3c9347351a

View File

@ -113,8 +113,6 @@ struct smmu_pmu {
u64 counter_mask;
u32 options;
bool global_filter;
u32 global_filter_span;
u32 global_filter_sid;
};
#define to_smmu_pmu(p) (container_of(p, struct smmu_pmu, pmu))
@ -260,6 +258,19 @@ static void smmu_pmu_set_event_filter(struct perf_event *event,
smmu_pmu_set_smr(smmu_pmu, idx, sid);
}
static bool smmu_pmu_check_global_filter(struct perf_event *curr,
struct perf_event *new)
{
if (get_filter_enable(new) != get_filter_enable(curr))
return false;
if (!get_filter_enable(new))
return true;
return get_filter_span(new) == get_filter_span(curr) &&
get_filter_stream_id(new) == get_filter_stream_id(curr);
}
static int smmu_pmu_apply_event_filter(struct smmu_pmu *smmu_pmu,
struct perf_event *event, int idx)
{
@ -279,17 +290,14 @@ static int smmu_pmu_apply_event_filter(struct smmu_pmu *smmu_pmu,
}
/* Requested settings same as current global settings*/
if (span == smmu_pmu->global_filter_span &&
sid == smmu_pmu->global_filter_sid)
idx = find_first_bit(smmu_pmu->used_counters, num_ctrs);
if (idx == num_ctrs ||
smmu_pmu_check_global_filter(smmu_pmu->events[idx], event)) {
smmu_pmu_set_event_filter(event, 0, span, sid);
return 0;
}
if (!bitmap_empty(smmu_pmu->used_counters, num_ctrs))
return -EAGAIN;
smmu_pmu_set_event_filter(event, 0, span, sid);
smmu_pmu->global_filter_span = span;
smmu_pmu->global_filter_sid = sid;
return 0;
return -EAGAIN;
}
static int smmu_pmu_get_event_idx(struct smmu_pmu *smmu_pmu,
@ -312,6 +320,19 @@ static int smmu_pmu_get_event_idx(struct smmu_pmu *smmu_pmu,
return idx;
}
static bool smmu_pmu_events_compatible(struct perf_event *curr,
struct perf_event *new)
{
if (new->pmu != curr->pmu)
return false;
if (to_smmu_pmu(new->pmu)->global_filter &&
!smmu_pmu_check_global_filter(curr, new))
return false;
return true;
}
/*
* Implementation of abstract pmu functionality required by
* the core perf events code.
@ -349,7 +370,7 @@ static int smmu_pmu_event_init(struct perf_event *event)
/* Don't allow groups with mixed PMUs, except for s/w events */
if (!is_software_event(event->group_leader)) {
if (event->group_leader->pmu != event->pmu)
if (!smmu_pmu_events_compatible(event->group_leader, event))
return -EINVAL;
if (++group_num_events > smmu_pmu->num_counters)
@ -360,7 +381,7 @@ static int smmu_pmu_event_init(struct perf_event *event)
if (is_software_event(sibling))
continue;
if (sibling->pmu != event->pmu)
if (!smmu_pmu_events_compatible(sibling, event))
return -EINVAL;
if (++group_num_events > smmu_pmu->num_counters)