diff options
| -rw-r--r-- | arch/x86/events/amd/ibs.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/arch/x86/events/amd/ibs.c b/arch/x86/events/amd/ibs.c index ea323dc182a6..40669eac9d6d 100644 --- a/arch/x86/events/amd/ibs.c +++ b/arch/x86/events/amd/ibs.c @@ -89,6 +89,7 @@ struct perf_ibs { u64 max_period; unsigned long offset_mask[1]; int offset_max; + unsigned int fetch_count_reset_broken : 1; struct cpu_perf_ibs __percpu *pcpu; struct attribute **format_attrs; @@ -370,7 +371,12 @@ perf_ibs_event_update(struct perf_ibs *perf_ibs, struct perf_event *event, static inline void perf_ibs_enable_event(struct perf_ibs *perf_ibs, struct hw_perf_event *hwc, u64 config) { - wrmsrl(hwc->config_base, hwc->config | config | perf_ibs->enable_mask); + u64 tmp = hwc->config | config; + + if (perf_ibs->fetch_count_reset_broken) + wrmsrl(hwc->config_base, tmp & ~perf_ibs->enable_mask); + + wrmsrl(hwc->config_base, tmp | perf_ibs->enable_mask); } /* @@ -756,6 +762,13 @@ static __init void perf_event_ibs_init(void) { struct attribute **attr = ibs_op_format_attrs; + /* + * Some chips fail to reset the fetch count when it is written; instead + * they need a 0-1 transition of IbsFetchEn. + */ + if (boot_cpu_data.x86 >= 0x16 && boot_cpu_data.x86 <= 0x18) + perf_ibs_fetch.fetch_count_reset_broken = 1; + perf_ibs_pmu_init(&perf_ibs_fetch, "ibs_fetch"); if (ibs_caps & IBS_CAPS_OPCNT) { |