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perf tools: Add the ability to specify list of cpus to monitor

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This patch adds a -C option to stat, record, top to designate a list of CPUs to
monitor. CPUs can be specified as a comma-separated list or ranges, no space
allowed.

Examples:
$ perf record -a -C0-1,4-7 sleep 1
$ perf top -C0-4
$ perf stat -a -C1,2,3,4 sleep 1

With perf record in per-thread mode with inherit mode on, samples are collected
only when the thread runs on the designated CPUs.

The -C option does not turn on system-wide mode automatically.

Cc: David S. Miller <davem@davemloft.net>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <4bff9496.d345d80a.41fe.7b00@mx.google.com>
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Stephane Eranian
2010-05-28 12:00:01 +02:00
committed by Arnaldo Carvalho de Melo
parent 761844b9c6
commit c45c6ea2e5
8 changed files with 110 additions and 24 deletions
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57
tools/perf/util/cpumap.c
View File

@@ -20,7 +20,7 @@ static int default_cpu_map(void)
return nr_cpus;
}
int read_cpu_map(void)
static int read_all_cpu_map(void)
{
FILE *onlnf;
int nr_cpus = 0;
@@ -57,3 +57,58 @@ int read_cpu_map(void)
return default_cpu_map();
}
int read_cpu_map(const char *cpu_list)
{
unsigned long start_cpu, end_cpu = 0;
char *p = NULL;
int i, nr_cpus = 0;
if (!cpu_list)
return read_all_cpu_map();
if (!isdigit(*cpu_list))
goto invalid;
while (isdigit(*cpu_list)) {
p = NULL;
start_cpu = strtoul(cpu_list, &p, 0);
if (start_cpu >= INT_MAX
|| (*p != '\0' && *p != ',' && *p != '-'))
goto invalid;
if (*p == '-') {
cpu_list = ++p;
p = NULL;
end_cpu = strtoul(cpu_list, &p, 0);
if (end_cpu >= INT_MAX || (*p != '\0' && *p != ','))
goto invalid;
if (end_cpu < start_cpu)
goto invalid;
} else {
end_cpu = start_cpu;
}
for (; start_cpu <= end_cpu; start_cpu++) {
/* check for duplicates */
for (i = 0; i < nr_cpus; i++)
if (cpumap[i] == (int)start_cpu)
goto invalid;
assert(nr_cpus < MAX_NR_CPUS);
cpumap[nr_cpus++] = (int)start_cpu;
}
if (*p)
++p;
cpu_list = p;
}
if (nr_cpus > 0)
return nr_cpus;
return default_cpu_map();
invalid:
return -1;
}