diff options
| author | Ravi Bangoria <ravi.bangoria@amd.com> | 2023-06-20 14:46:03 +0530 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-07-10 09:52:34 +0200 |
| commit | 7c2128235eff99b448af8f4b5b2933495bf1a440 (patch) | |
| tree | f7f04f22933d60272bac4952840dc6e387e9d5b2 /arch/x86/events | |
| parent | 06c2afb862f9da8dc5efa4b6076a0e48c3fbaaa5 (diff) | |
perf/amd: Prevent grouping of IBS events
IBS PMUs can have only one event active at any point in time. Restrict
grouping of multiple IBS events.
Reported-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20230620091603.269-1-ravi.bangoria@amd.com
Diffstat (limited to 'arch/x86/events')
| -rw-r--r-- | arch/x86/events/amd/ibs.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c index 371014802191..74e664266753 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -247,11 +247,33 @@ int forward_event_to_ibs(struct perf_event *event) return -ENOENT; } +/* + * Grouping of IBS events is not possible since IBS can have only + * one event active at any point in time. + */ +static int validate_group(struct perf_event *event) +{ + struct perf_event *sibling; + + if (event->group_leader == event) + return 0; + + if (event->group_leader->pmu == event->pmu) + return -EINVAL; + + for_each_sibling_event(sibling, event->group_leader) { + if (sibling->pmu == event->pmu) + return -EINVAL; + } + return 0; +} + static int perf_ibs_init(struct perf_event *event) { struct hw_perf_event *hwc = &event->hw; struct perf_ibs *perf_ibs; u64 max_cnt, config; + int ret; perf_ibs = get_ibs_pmu(event->attr.type); if (!perf_ibs) @@ -265,6 +287,10 @@ static int perf_ibs_init(struct perf_event *event) if (config & ~perf_ibs->config_mask) return -EINVAL; + ret = validate_group(event); + if (ret) + return ret; + if (hwc->sample_period) { if (config & perf_ibs->cnt_mask) /* raw max_cnt may not be set */ |