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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2023-10-01 19:34:53 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2023-10-01 19:34:53 +0300 |
| commit | 3a38c57a87aeb5c6d71a1b6dd572569112dbce38 (patch) | |
| tree | 7318c7f4e97923b59de94b93e4175b24e093d8d2 | |
| parent | e402b08634b398e9feb94902c7adcf05bb8ba47d (diff) | |
| parent | 599522d9d2e19d6240e4312577f1c5f3ffca22f6 (diff) | |
| download | linux-3a38c57a87aeb5c6d71a1b6dd572569112dbce38.tar.xz | |
Merge tag 'perf-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf event fixes from Ingo Molnar:
"Misc fixes: work around an AMD microcode bug on certain models, and
fix kexec kernel PMI handlers on AMD systems that get loaded on older
kernels that have an unexpected register state"
* tag 'perf-urgent-2023-10-01' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/amd: Do not WARN() on every IRQ
perf/x86/amd/core: Fix overflow reset on hotplug
| -rw-r--r-- | arch/x86/events/amd/core.c | 24 |
1 files changed, 17 insertions, 7 deletions
diff --git a/arch/x86/events/amd/core.c b/arch/x86/events/amd/core.c index abadd5f23425..e24976593a29 100644 --- a/arch/x86/events/amd/core.c +++ b/arch/x86/events/amd/core.c @@ -534,8 +534,12 @@ static void amd_pmu_cpu_reset(int cpu) /* Clear enable bits i.e. PerfCntrGlobalCtl.PerfCntrEn */ wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, 0); - /* Clear overflow bits i.e. PerfCntrGLobalStatus.PerfCntrOvfl */ - wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, amd_pmu_global_cntr_mask); + /* + * Clear freeze and overflow bits i.e. PerfCntrGLobalStatus.LbrFreeze + * and PerfCntrGLobalStatus.PerfCntrOvfl + */ + wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, + GLOBAL_STATUS_LBRS_FROZEN | amd_pmu_global_cntr_mask); } static int amd_pmu_cpu_prepare(int cpu) @@ -570,6 +574,7 @@ static void amd_pmu_cpu_starting(int cpu) int i, nb_id; cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY; + amd_pmu_cpu_reset(cpu); if (!x86_pmu.amd_nb_constraints) return; @@ -591,8 +596,6 @@ static void amd_pmu_cpu_starting(int cpu) cpuc->amd_nb->nb_id = nb_id; cpuc->amd_nb->refcnt++; - - amd_pmu_cpu_reset(cpu); } static void amd_pmu_cpu_dead(int cpu) @@ -601,6 +604,7 @@ static void amd_pmu_cpu_dead(int cpu) kfree(cpuhw->lbr_sel); cpuhw->lbr_sel = NULL; + amd_pmu_cpu_reset(cpu); if (!x86_pmu.amd_nb_constraints) return; @@ -613,8 +617,6 @@ static void amd_pmu_cpu_dead(int cpu) cpuhw->amd_nb = NULL; } - - amd_pmu_cpu_reset(cpu); } static inline void amd_pmu_set_global_ctl(u64 ctl) @@ -884,7 +886,7 @@ static int amd_pmu_v2_handle_irq(struct pt_regs *regs) struct hw_perf_event *hwc; struct perf_event *event; int handled = 0, idx; - u64 status, mask; + u64 reserved, status, mask; bool pmu_enabled; /* @@ -909,6 +911,14 @@ static int amd_pmu_v2_handle_irq(struct pt_regs *regs) status &= ~GLOBAL_STATUS_LBRS_FROZEN; } + reserved = status & ~amd_pmu_global_cntr_mask; + if (reserved) + pr_warn_once("Reserved PerfCntrGlobalStatus bits are set (0x%llx), please consider updating microcode\n", + reserved); + + /* Clear any reserved bits set by buggy microcode */ + status &= amd_pmu_global_cntr_mask; + for (idx = 0; idx < x86_pmu.num_counters; idx++) { if (!test_bit(idx, cpuc->active_mask)) continue; |