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authorJan Stancek <jstancek@redhat.com>2017-02-17 12:10:24 +0100
committerArnaldo Carvalho de Melo <acme@redhat.com>2017-02-17 16:33:05 +0100
commit92a7e1278005b6bb3459affc50b2b6e2464e7e7c (patch)
tree54f07cee8f0a9eb221f3a58324d5fe9417d885fa /tools/perf/util/cpumap.c
parentperf session: Fix DEBUG=1 build with clang (diff)
downloadlinux-92a7e1278005b6bb3459affc50b2b6e2464e7e7c.tar.xz
linux-92a7e1278005b6bb3459affc50b2b6e2464e7e7c.zip
perf cpumap: Add cpu__max_present_cpu()
Similar to cpu__max_cpu() (which returns the max possible CPU), returns the max present CPU. Signed-off-by: Jan Stancek <jstancek@redhat.com> Acked-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/8ea4601b5cacc49927235b4ebac424bd6eeccb06.1487146877.git.jstancek@redhat.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Diffstat (limited to 'tools/perf/util/cpumap.c')
-rw-r--r--tools/perf/util/cpumap.c22
1 files changed, 22 insertions, 0 deletions
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)) {