>From 9bf8ece1e397b851beedaeceeb0cd07421ff6f43 Mon Sep 17 00:00:00 2001 Message-Id: <9bf8ece1e397b851beedaeceeb0cd07421ff6f43.1485877985.git.jstancek@redhat.com> From: Jan Stancek Date: Tue, 31 Jan 2017 14:41:46 +0100 Subject: [PATCH 1/3 v2] perf: add cpu__max_present_cpu() Similar to cpu__max_cpu() (which returns max possible CPU), returns max present CPU. Signed-off-by: Jan Stancek --- tools/perf/util/cpumap.c | 22 ++++++++++++++++++++++ tools/perf/util/cpumap.h | 1 + 2 files changed, 23 insertions(+) diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c index 2c0b52264a46..8c7504939113 100644 --- a/tools/perf/util/cpumap.c +++ b/tools/perf/util/cpumap.c @@ -9,6 +9,7 @@ #include "asm/bug.h" static int max_cpu_num; +static int max_present_cpu_num; static int max_node_num; static int *cpunode_map; @@ -442,6 +443,7 @@ static void set_max_cpu_num(void) /* set up default */ max_cpu_num = 4096; + max_present_cpu_num = 4096; mnt = sysfs__mountpoint(); if (!mnt) @@ -455,6 +457,17 @@ static void set_max_cpu_num(void) } ret = get_max_num(path, &max_cpu_num); + if (ret) + goto out; + + /* get the highest present cpu number for a sparse allocation */ + ret = snprintf(path, PATH_MAX, "%s/devices/system/cpu/present", mnt); + if (ret == PATH_MAX) { + pr_err("sysfs path crossed PATH_MAX(%d) size\n", PATH_MAX); + goto out; + } + + ret = get_max_num(path, &max_present_cpu_num); out: if (ret) @@ -505,6 +518,15 @@ int cpu__max_cpu(void) return max_cpu_num; } +int cpu__max_present_cpu(void) +{ + if (unlikely(!max_present_cpu_num)) + set_max_cpu_num(); + + return max_present_cpu_num; +} + + int cpu__get_node(int cpu) { if (unlikely(cpunode_map == NULL)) { diff --git a/tools/perf/util/cpumap.h b/tools/perf/util/cpumap.h index 06bd689f5989..1a0549af8f5c 100644 --- a/tools/perf/util/cpumap.h +++ b/tools/perf/util/cpumap.h @@ -62,6 +62,7 @@ static inline bool cpu_map__empty(const struct cpu_map *map) int cpu__max_node(void); int cpu__max_cpu(void); +int cpu__max_present_cpu(void); int cpu__get_node(int cpu); int cpu_map__build_map(struct cpu_map *cpus, struct cpu_map **res, -- 1.8.3.1