The following commit has been merged into the perf/core branch of tip: Commit-ID: fda1f99f34a8f0975086bcfef34da865009995c1 Gitweb: https://git.kernel.org/tip/fda1f99f34a8f0975086bcfef34da865009995c1 Author: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> AuthorDate: Fri, 03 Jul 2020 05:49:18 -07:00 Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx> CommitterDate: Wed, 08 Jul 2020 11:38:54 +02:00 perf/x86/intel/lbr: Factor out rdlbr_all() and wrlbr_all() The previous model-specific LBR and Architecture LBR (legacy way) use a similar method to save/restore the LBR information, which directly accesses the LBR registers. The codes which read/write a set of LBR registers can be shared between them. Factor out two functions which are used to read/write a set of LBR registers. Add lbr_info into structure x86_pmu, and use it to replace the hardcoded LBR INFO MSR, because the LBR INFO MSR address of the previous model-specific LBR is different from Architecture LBR. The MSR address should be assigned at boot time. For now, only Sky Lake and later platforms have the LBR INFO MSR. Signed-off-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx> Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx> Link: https://lkml.kernel.org/r/1593780569-62993-13-git-send-email-kan.liang@xxxxxxxxxxxxxxx --- arch/x86/events/intel/lbr.c | 66 ++++++++++++++++++++++++++--------- arch/x86/events/perf_event.h | 2 +- 2 files changed, 51 insertions(+), 17 deletions(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 21f4f07..d3d129c 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -237,7 +237,7 @@ void intel_pmu_lbr_reset_64(void) wrmsrl(x86_pmu.lbr_from + i, 0); wrmsrl(x86_pmu.lbr_to + i, 0); if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) - wrmsrl(MSR_LBR_INFO_0 + i, 0); + wrmsrl(x86_pmu.lbr_info + i, 0); } } @@ -343,6 +343,11 @@ static __always_inline void wrlbr_to(unsigned int idx, u64 val) wrmsrl(x86_pmu.lbr_to + idx, val); } +static __always_inline void wrlbr_info(unsigned int idx, u64 val) +{ + wrmsrl(x86_pmu.lbr_info + idx, val); +} + static __always_inline u64 rdlbr_from(unsigned int idx) { u64 val; @@ -361,8 +366,44 @@ static __always_inline u64 rdlbr_to(unsigned int idx) return val; } +static __always_inline u64 rdlbr_info(unsigned int idx) +{ + u64 val; + + rdmsrl(x86_pmu.lbr_info + idx, val); + + return val; +} + +static inline void +wrlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) +{ + wrlbr_from(idx, lbr->from); + wrlbr_to(idx, lbr->to); + if (need_info) + wrlbr_info(idx, lbr->info); +} + +static inline bool +rdlbr_all(struct lbr_entry *lbr, unsigned int idx, bool need_info) +{ + u64 from = rdlbr_from(idx); + + /* Don't read invalid entry */ + if (!from) + return false; + + lbr->from = from; + lbr->to = rdlbr_to(idx); + if (need_info) + lbr->info = rdlbr_info(idx); + + return true; +} + void intel_pmu_lbr_restore(void *ctx) { + bool need_info = x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct x86_perf_task_context *task_ctx = ctx; int i; @@ -372,11 +413,7 @@ void intel_pmu_lbr_restore(void *ctx) mask = x86_pmu.lbr_nr - 1; for (i = 0; i < task_ctx->valid_lbrs; i++) { lbr_idx = (tos - i) & mask; - wrlbr_from(lbr_idx, task_ctx->lbr[i].from); - wrlbr_to(lbr_idx, task_ctx->lbr[i].to); - - if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) - wrmsrl(MSR_LBR_INFO_0 + lbr_idx, task_ctx->lbr[i].info); + wrlbr_all(&task_ctx->lbr[i], lbr_idx, need_info); } for (; i < x86_pmu.lbr_nr; i++) { @@ -384,7 +421,7 @@ void intel_pmu_lbr_restore(void *ctx) wrlbr_from(lbr_idx, 0); wrlbr_to(lbr_idx, 0); if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) - wrmsrl(MSR_LBR_INFO_0 + lbr_idx, 0); + wrlbr_info(lbr_idx, 0); } wrmsrl(x86_pmu.lbr_tos, tos); @@ -427,23 +464,19 @@ static void __intel_pmu_lbr_restore(void *ctx) void intel_pmu_lbr_save(void *ctx) { + bool need_info = x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO; struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); struct x86_perf_task_context *task_ctx = ctx; unsigned lbr_idx, mask; - u64 tos, from; + u64 tos; int i; mask = x86_pmu.lbr_nr - 1; tos = intel_pmu_lbr_tos(); for (i = 0; i < x86_pmu.lbr_nr; i++) { lbr_idx = (tos - i) & mask; - from = rdlbr_from(lbr_idx); - if (!from) + if (!rdlbr_all(&task_ctx->lbr[i], lbr_idx, need_info)) break; - task_ctx->lbr[i].from = from; - task_ctx->lbr[i].to = rdlbr_to(lbr_idx); - if (x86_pmu.intel_cap.lbr_format == LBR_FORMAT_INFO) - rdmsrl(MSR_LBR_INFO_0 + lbr_idx, task_ctx->lbr[i].info); } task_ctx->valid_lbrs = i; task_ctx->tos = tos; @@ -689,7 +722,7 @@ void intel_pmu_lbr_read_64(struct cpu_hw_events *cpuc) if (lbr_format == LBR_FORMAT_INFO && need_info) { u64 info; - rdmsrl(MSR_LBR_INFO_0 + lbr_idx, info); + info = rdlbr_info(lbr_idx); mis = !!(info & LBR_INFO_MISPRED); pred = !mis; in_tx = !!(info & LBR_INFO_IN_TX); @@ -1336,6 +1369,7 @@ __init void intel_pmu_lbr_init_skl(void) x86_pmu.lbr_tos = MSR_LBR_TOS; x86_pmu.lbr_from = MSR_LBR_NHM_FROM; x86_pmu.lbr_to = MSR_LBR_NHM_TO; + x86_pmu.lbr_info = MSR_LBR_INFO_0; x86_pmu.lbr_sel_mask = LBR_SEL_MASK; x86_pmu.lbr_sel_map = hsw_lbr_sel_map; @@ -1421,7 +1455,7 @@ int x86_perf_get_lbr(struct x86_pmu_lbr *lbr) lbr->nr = x86_pmu.lbr_nr; lbr->from = x86_pmu.lbr_from; lbr->to = x86_pmu.lbr_to; - lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? MSR_LBR_INFO_0 : 0; + lbr->info = (lbr_fmt == LBR_FORMAT_INFO) ? x86_pmu.lbr_info : 0; return 0; } diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index aaa426d..20e35cb 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -690,7 +690,7 @@ struct x86_pmu { * Intel LBR */ unsigned int lbr_tos, lbr_from, lbr_to, - lbr_nr; /* LBR base regs and size */ + lbr_info, lbr_nr; /* LBR base regs and size */ union { u64 lbr_sel_mask; /* LBR_SELECT valid bits */ u64 lbr_ctl_mask; /* LBR_CTL valid bits */
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