From f3be1e7b2cf8bc096386a3588fc640b0db6b28d7 Mon Sep 17 00:00:00 2001 From: Reinette Chatre Date: Fri, 22 Jun 2018 15:42:29 -0700 Subject: [PATCH] x86/intel_rdt: Support L3 cache performance event of Broadwell Broadwell microarchitecture supports pseudo-locking. Add support for the L3 cache related performance events of these systems so that the success of pseudo-locking can be measured more accurately on these platforms. Signed-off-by: Reinette Chatre Signed-off-by: Thomas Gleixner Cc: fenghua.yu@intel.com Cc: tony.luck@intel.com Cc: vikas.shivappa@linux.intel.com Cc: gavin.hindman@intel.com Cc: jithu.joseph@intel.com Cc: dave.hansen@intel.com Cc: hpa@zytor.com Link: https://lkml.kernel.org/r/36c1414e9bd17c3faf440f32b644b9c879bcbae2.1529706536.git.reinette.chatre@intel.com --- arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c | 56 +++++++++++++++++++ .../kernel/cpu/intel_rdt_pseudo_lock_event.h | 10 ++++ 2 files changed, 66 insertions(+) diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c index 9e808c07a7f0..dd1341557c9d 100644 --- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c +++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock.c @@ -850,6 +850,8 @@ static int measure_cycles_lat_fn(void *_plr) static int measure_cycles_perf_fn(void *_plr) { + unsigned long long l3_hits = 0, l3_miss = 0; + u64 l3_hit_bits = 0, l3_miss_bits = 0; struct pseudo_lock_region *plr = _plr; unsigned long long l2_hits, l2_miss; u64 l2_hit_bits, l2_miss_bits; @@ -883,6 +885,16 @@ static int measure_cycles_perf_fn(void *_plr) * L2_HIT 02H * L1_MISS 08H * L2_MISS 10H + * + * On Broadwell Microarchitecture the MEM_LOAD_UOPS_RETIRED event + * has two "no fix" errata associated with it: BDM35 and BDM100. On + * this platform we use the following events instead: + * L2_RQSTS 24H (Documented in https://download.01.org/perfmon/BDW/) + * REFERENCES FFH + * MISS 3FH + * LONGEST_LAT_CACHE 2EH (Documented in SDM) + * REFERENCE 4FH + * MISS 41H */ /* @@ -901,6 +913,14 @@ static int measure_cycles_perf_fn(void *_plr) l2_hit_bits = (0x52ULL << 16) | (0x2 << 8) | 0xd1; l2_miss_bits = (0x52ULL << 16) | (0x10 << 8) | 0xd1; break; + case INTEL_FAM6_BROADWELL_X: + /* On BDW the l2_hit_bits count references, not hits */ + l2_hit_bits = (0x52ULL << 16) | (0xff << 8) | 0x24; + l2_miss_bits = (0x52ULL << 16) | (0x3f << 8) | 0x24; + /* On BDW the l3_hit_bits count references, not hits */ + l3_hit_bits = (0x52ULL << 16) | (0x4f << 8) | 0x2e; + l3_miss_bits = (0x52ULL << 16) | (0x41 << 8) | 0x2e; + break; default: goto out; } @@ -917,9 +937,21 @@ static int measure_cycles_perf_fn(void *_plr) pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1, 0x0); pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0, 0x0); pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 1, 0x0); + if (l3_hit_bits > 0) { + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2, 0x0); + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3, 0x0); + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 2, 0x0); + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_PERFCTR0 + 3, 0x0); + } /* Set and enable the L2 counters */ pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0, l2_hit_bits); pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1, l2_miss_bits); + if (l3_hit_bits > 0) { + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2, + l3_hit_bits); + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3, + l3_miss_bits); + } mem_r = plr->kmem; size = plr->size; line_size = plr->line_size; @@ -937,11 +969,35 @@ static int measure_cycles_perf_fn(void *_plr) l2_hit_bits & ~(0x40ULL << 16)); pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 1, l2_miss_bits & ~(0x40ULL << 16)); + if (l3_hit_bits > 0) { + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 2, + l3_hit_bits & ~(0x40ULL << 16)); + pseudo_wrmsrl_notrace(MSR_ARCH_PERFMON_EVENTSEL0 + 3, + l3_miss_bits & ~(0x40ULL << 16)); + } l2_hits = native_read_pmc(0); l2_miss = native_read_pmc(1); + if (l3_hit_bits > 0) { + l3_hits = native_read_pmc(2); + l3_miss = native_read_pmc(3); + } wrmsr(MSR_MISC_FEATURE_CONTROL, 0x0, 0x0); local_irq_enable(); + /* + * On BDW we count references and misses, need to adjust. Sometimes + * the "hits" counter is a bit more than the references, for + * example, x references but x + 1 hits. To not report invalid + * hit values in this case we treat that as misses eaqual to + * references. + */ + if (boot_cpu_data.x86_model == INTEL_FAM6_BROADWELL_X) + l2_hits -= (l2_miss > l2_hits ? l2_hits : l2_miss); trace_pseudo_lock_l2(l2_hits, l2_miss); + if (l3_hit_bits > 0) { + if (boot_cpu_data.x86_model == INTEL_FAM6_BROADWELL_X) + l3_hits -= (l3_miss > l3_hits ? l3_hits : l3_miss); + trace_pseudo_lock_l3(l3_hits, l3_miss); + } out: plr->thread_done = 1; diff --git a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock_event.h b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock_event.h index efad50d2ee2f..2c041e6d9f05 100644 --- a/arch/x86/kernel/cpu/intel_rdt_pseudo_lock_event.h +++ b/arch/x86/kernel/cpu/intel_rdt_pseudo_lock_event.h @@ -25,6 +25,16 @@ TRACE_EVENT(pseudo_lock_l2, TP_printk("hits=%llu miss=%llu", __entry->l2_hits, __entry->l2_miss)); +TRACE_EVENT(pseudo_lock_l3, + TP_PROTO(u64 l3_hits, u64 l3_miss), + TP_ARGS(l3_hits, l3_miss), + TP_STRUCT__entry(__field(u64, l3_hits) + __field(u64, l3_miss)), + TP_fast_assign(__entry->l3_hits = l3_hits; + __entry->l3_miss = l3_miss;), + TP_printk("hits=%llu miss=%llu", + __entry->l3_hits, __entry->l3_miss)); + #endif /* _TRACE_PSEUDO_LOCK_H */ #undef TRACE_INCLUDE_PATH -- 2.30.2