From 2a57d40832dc8366bc517bcbbfdb1d7fb583735b Mon Sep 17 00:00:00 2001 From: Kan Liang Date: Tue, 2 Feb 2021 12:09:06 -0800 Subject: [PATCH] perf tools: Support the auxiliary event On the Intel Sapphire Rapids server, an auxiliary event has to be enabled simultaneously with the load latency event to retrieve complete Memory Info. Add X86 specific perf_mem_events__name() to handle the auxiliary event. - Users are only interested in the samples of the mem-loads event. Sample read the auxiliary event. - The auxiliary event must be in front of the load latency event in a group. Assume the second event to sample if the auxiliary event is the leader. - Add a weak is_mem_loads_aux_event() to check the auxiliary event for X86. For other ARCHs, it always return false. Parse the unique event name, mem-loads-aux, for the auxiliary event. Committer notes: According to 61b985e3e775a3a7 ("perf/x86/intel: Add perf core PMU support for Sapphire Rapids"), ENODATA is only returned by sys_perf_event_open() when used with these auxiliary events, with this in evsel__open_strerror(): case ENODATA: return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. " "Please add an auxiliary event in front of the load latency event."); This is Ok at this point in time, but fragile long term, I pointed this out in the e-mail thread, requesting a follow up patch to check if ENODATA is really for this specific case. Fixed up sizeof(MEM_LOADS_AUX_NAME) bug pointed out by Namhyung. Signed-off-by: Kan Liang Cc: Andi Kleen Cc: Jin Yao Cc: Jiri Olsa Cc: Madhavan Srinivasan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lore.kernel.org/lkml/20210205152648.GC920417@kernel.org Link: http://lore.kernel.org/lkml/1612296553-21962-3-git-send-email-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/arch/x86/util/Build | 1 + tools/perf/arch/x86/util/mem-events.c | 44 +++++++++++++++++++++++++++++++++++ tools/perf/util/evsel.c | 3 +++ tools/perf/util/mem-events.c | 5 ++++ tools/perf/util/mem-events.h | 2 ++ tools/perf/util/parse-events.l | 1 + tools/perf/util/record.c | 5 +++- 7 files changed, 60 insertions(+), 1 deletion(-) create mode 100644 tools/perf/arch/x86/util/mem-events.c diff --git a/tools/perf/arch/x86/util/Build b/tools/perf/arch/x86/util/Build index ce1ec92..9801461 100644 --- a/tools/perf/arch/x86/util/Build +++ b/tools/perf/arch/x86/util/Build @@ -7,6 +7,7 @@ perf-y += topdown.o perf-y += machine.o perf-y += event.o perf-y += evlist.o +perf-y += mem-events.o perf-$(CONFIG_DWARF) += dwarf-regs.o perf-$(CONFIG_BPF_PROLOGUE) += dwarf-regs.o diff --git a/tools/perf/arch/x86/util/mem-events.c b/tools/perf/arch/x86/util/mem-events.c new file mode 100644 index 0000000..588110f --- /dev/null +++ b/tools/perf/arch/x86/util/mem-events.c @@ -0,0 +1,44 @@ +// SPDX-License-Identifier: GPL-2.0 +#include "util/pmu.h" +#include "map_symbol.h" +#include "mem-events.h" + +static char mem_loads_name[100]; +static bool mem_loads_name__init; + +#define MEM_LOADS_AUX 0x8203 +#define MEM_LOADS_AUX_NAME "{cpu/mem-loads-aux/,cpu/mem-loads,ldlat=%u/pp}:S" + +bool is_mem_loads_aux_event(struct evsel *leader) +{ + if (!pmu_have_event("cpu", "mem-loads-aux")) + return false; + + return leader->core.attr.config == MEM_LOADS_AUX; +} + +char *perf_mem_events__name(int i) +{ + struct perf_mem_event *e = perf_mem_events__ptr(i); + + if (!e) + return NULL; + + if (i == PERF_MEM_EVENTS__LOAD) { + if (mem_loads_name__init) + return mem_loads_name; + + mem_loads_name__init = true; + + if (pmu_have_event("cpu", "mem-loads-aux")) { + scnprintf(mem_loads_name, sizeof(mem_loads_name), + MEM_LOADS_AUX_NAME, perf_mem_events__loads_ldlat); + } else { + scnprintf(mem_loads_name, sizeof(mem_loads_name), + e->name, perf_mem_events__loads_ldlat); + } + return mem_loads_name; + } + + return (char *)e->name; +} diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 8b18ec5..a8ce6b2 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -2712,6 +2712,9 @@ int evsel__open_strerror(struct evsel *evsel, struct target *target, if (perf_missing_features.aux_output) return scnprintf(msg, size, "The 'aux_output' feature is not supported, update the kernel."); break; + case ENODATA: + return scnprintf(msg, size, "Cannot collect data source with the load latency event alone. " + "Please add an auxiliary event in front of the load latency event."); default: break; } diff --git a/tools/perf/util/mem-events.c b/tools/perf/util/mem-events.c index 19007e4..3edfb88 100644 --- a/tools/perf/util/mem-events.c +++ b/tools/perf/util/mem-events.c @@ -56,6 +56,11 @@ char * __weak perf_mem_events__name(int i) return (char *)e->name; } +__weak bool is_mem_loads_aux_event(struct evsel *leader __maybe_unused) +{ + return false; +} + int perf_mem_events__parse(const char *str) { char *tok, *saveptr = NULL; diff --git a/tools/perf/util/mem-events.h b/tools/perf/util/mem-events.h index 5ef1782..045a507 100644 --- a/tools/perf/util/mem-events.h +++ b/tools/perf/util/mem-events.h @@ -9,6 +9,7 @@ #include #include #include "stat.h" +#include "evsel.h" struct perf_mem_event { bool record; @@ -39,6 +40,7 @@ int perf_mem_events__init(void); char *perf_mem_events__name(int i); struct perf_mem_event *perf_mem_events__ptr(int i); +bool is_mem_loads_aux_event(struct evsel *leader); void perf_mem_events__list(void); diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index 9db5097..0b36285 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -356,6 +356,7 @@ bpf-output { return sym(yyscanner, PERF_TYPE_SOFTWARE, PERF_COUNT_SW_BPF_OUT cycles-ct | cycles-t | mem-loads | +mem-loads-aux | mem-stores | topdown-[a-z-]+ | tx-capacity-[a-z-]+ | diff --git a/tools/perf/util/record.c b/tools/perf/util/record.c index 1c1f24d..f99852d 100644 --- a/tools/perf/util/record.c +++ b/tools/perf/util/record.c @@ -15,6 +15,8 @@ #include "record.h" #include "../perf-sys.h" #include "topdown.h" +#include "map_symbol.h" +#include "mem-events.h" /* * evsel__config_leader_sampling() uses special rules for leader sampling. @@ -25,7 +27,8 @@ static struct evsel *evsel__read_sampler(struct evsel *evsel, struct evlist *evl { struct evsel *leader = evsel->leader; - if (evsel__is_aux_event(leader) || arch_topdown_sample_read(leader)) { + if (evsel__is_aux_event(leader) || arch_topdown_sample_read(leader) || + is_mem_loads_aux_event(leader)) { evlist__for_each_entry(evlist, evsel) { if (evsel->leader == leader && evsel != evsel->leader) return evsel; -- 2.7.4