perf cpumap: Introduce cpu_map__snprint_mask()
The cpu_map__snprint_mask() generates a string representation of a
cpumask bitmap. For cpu 0 to 11, it'll return "fff".
Committer notes:
Fix compiler warning on some toolchains:
19 fedora:24-x-ARC-uClibc: FAIL
CC /tmp/build/perf/util/cpumap.o
util/cpumap.c: In function 'hex_char':
util/cpumap.c:679:2: error: comparison is always true due to limited range of data type [-Werror=type-limits]
if (0 <= val && val <= 9)
^
cc1: all warnings being treated as errors
Applying patch from Namhyung that makes function receive an 'unsigned
char', that is what the callers are passing to this function.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20170224011251.14946-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/cpumap.c b/tools/perf/util/cpumap.c
index 39ad2ca..061018b 100644
--- a/tools/perf/util/cpumap.c
+++ b/tools/perf/util/cpumap.c
@@ -673,3 +673,49 @@ size_t cpu_map__snprint(struct cpu_map *map, char *buf, size_t size)
pr_debug("cpumask list: %s\n", buf);
return ret;
}
+
+static char hex_char(unsigned char val)
+{
+ if (val < 10)
+ return val + '0';
+ if (val < 16)
+ return val - 10 + 'a';
+ return '?';
+}
+
+size_t cpu_map__snprint_mask(struct cpu_map *map, char *buf, size_t size)
+{
+ int i, cpu;
+ char *ptr = buf;
+ unsigned char *bitmap;
+ int last_cpu = cpu_map__cpu(map, map->nr - 1);
+
+ bitmap = zalloc((last_cpu + 7) / 8);
+ if (bitmap == NULL) {
+ buf[0] = '\0';
+ return 0;
+ }
+
+ for (i = 0; i < map->nr; i++) {
+ cpu = cpu_map__cpu(map, i);
+ bitmap[cpu / 8] |= 1 << (cpu % 8);
+ }
+
+ for (cpu = last_cpu / 4 * 4; cpu >= 0; cpu -= 4) {
+ unsigned char bits = bitmap[cpu / 8];
+
+ if (cpu % 8)
+ bits >>= 4;
+ else
+ bits &= 0xf;
+
+ *ptr++ = hex_char(bits);
+ if ((cpu % 32) == 0 && cpu > 0)
+ *ptr++ = ',';
+ }
+ *ptr = '\0';
+ free(bitmap);
+
+ buf[size - 1] = '\0';
+ return ptr - buf;
+}