diff options
| author | Len Brown <len.brown@intel.com> | 2012-11-08 22:38:05 -0500 |
|---|---|---|
| committer | Len Brown <len.brown@intel.com> | 2012-11-27 00:03:06 -0500 |
| commit | e52966c084f9d9ea12be2ac7df801d610d4a19a5 (patch) | |
| tree | 4ea59e63067349ce8671cdcf7fe06a62c0b1933b /tools/power | |
| parent | 3fc808aaa052dec7b155f3242c6c0eabf0c49127 (diff) | |
| download | lwn-e52966c084f9d9ea12be2ac7df801d610d4a19a5.tar.gz lwn-e52966c084f9d9ea12be2ac7df801d610d4a19a5.zip | |
tools/power turbostat: prevent infinite loop on migration error path
Turbostat assumed if it can't migrate to a CPU, then the CPU
must have gone off-line and turbostat should re-initialize
with the new topology.
But if turbostat can not migrate because it is restricted by
a cpuset, then it will fail to migrate even after re-initialization,
resulting in an infinite loop.
Spit out a warning when we can't migrate
and endure only 2 re-initialize cycles in a row
before giving up and exiting.
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'tools/power')
| -rw-r--r-- | tools/power/x86/turbostat/turbostat.c | 11 |
1 files changed, 10 insertions, 1 deletions
diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index 3c063a00f3bf..77e76b11382f 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -656,8 +656,10 @@ int get_counters(struct thread_data *t, struct core_data *c, struct pkg_data *p) { int cpu = t->cpu_id; - if (cpu_migrate(cpu)) + if (cpu_migrate(cpu)) { + fprintf(stderr, "Could not migrate to CPU %d\n", cpu); return -1; + } t->tsc = rdtsc(); /* we are running on local CPU of interest */ @@ -1088,15 +1090,22 @@ int mark_cpu_present(int cpu) void turbostat_loop() { int retval; + int restarted = 0; restart: + restarted++; + retval = for_all_cpus(get_counters, EVEN_COUNTERS); if (retval < -1) { exit(retval); } else if (retval == -1) { + if (restarted > 1) { + exit(retval); + } re_initialize(); goto restart; } + restarted = 0; gettimeofday(&tv_even, (struct timezone *)NULL); while (1) { |