diff options
| author | Ingo Molnar <mingo@elte.hu> | 2009-06-07 17:39:02 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-06-07 17:39:02 +0200 |
| commit | 3da297a60f7e8840f79f7d0b343af078890939ea (patch) | |
| tree | c3b5b39be914caa30f1eb820afbdc228d531e25e /tools/perf/builtin-top.c | |
| parent | 716c69fecacd42f2a304a97158e04af2786a3f65 (diff) | |
perf record: Fall back to cpu-clock-ticks if no PMU
On architectures/CPUs without PMU support but with perfcounters
enabled 'perf record' currently fails because it cannot create a
cycle based hw-perfcounter.
Fall back to the cpu-clock-tick sw-perfcounter in this case, which
is hrtimer based and will always work (as long as perfcounters
are enabled).
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'tools/perf/builtin-top.c')
| -rw-r--r-- | tools/perf/builtin-top.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 6da30a140e8..1f8c97d5c32 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -65,6 +65,7 @@ static int group = 0; static unsigned int page_size; static unsigned int mmap_pages = 16; static int freq = 0; +static int verbose = 0; static char *sym_filter; static unsigned long filter_start; @@ -550,11 +551,12 @@ try_again: if (fd[i][counter] < 0) { int err = errno; - error("sys_perf_counter_open() syscall returned with %d (%s)\n", - fd[i][counter], strerror(err)); + if (verbose) + error("sys_perf_counter_open() syscall returned with %d (%s)\n", + fd[i][counter], strerror(err)); if (err == EPERM) - die(" No permission - are you root?\n"); + die("No permission - are you root?\n"); /* * If it's cycles then fall back to hrtimer * based cpu-clock-tick sw counter, which @@ -563,7 +565,9 @@ try_again: if (attr->type == PERF_TYPE_HARDWARE && attr->config == PERF_COUNT_CPU_CYCLES) { - warning(" ... trying to fall back to cpu-clock-ticks\n"); + if (verbose) + warning(" ... trying to fall back to cpu-clock-ticks\n"); + attr->type = PERF_TYPE_SOFTWARE; attr->config = PERF_COUNT_CPU_CLOCK; goto try_again; @@ -673,6 +677,8 @@ static const struct option options[] = { "profile at this frequency"), OPT_INTEGER('E', "entries", &print_entries, "display this many functions"), + OPT_BOOLEAN('v', "verbose", &verbose, + "be more verbose (show counter open errors, etc)"), OPT_END() }; |