Commit 15aaa346 authored by Len Brown's avatar Len Brown

tools turbostat: harden against cpu online/offline

Sometimes users have turbostat running in interval mode
when they take processors offline/online.

Previously, turbostat would survive, but not gracefully.

Tighten up the error checking so turbostat notices
changesn sooner, and print just 1 line on change:

turbostat: re-initialized with num_cpus %d
Signed-off-by: default avatarLen Brown <len.brown@intel.com>
parent 88c3281f
......@@ -71,7 +71,6 @@ unsigned int show_cpu;
int aperf_mperf_unstable;
int backwards_count;
char *progname;
int need_reinitialize;
int num_cpus;
cpu_set_t *cpu_mask;
......@@ -138,30 +137,24 @@ int cpu_migrate(int cpu)
return 0;
}
unsigned long long get_msr(int cpu, off_t offset)
int get_msr(int cpu, off_t offset, unsigned long long *msr)
{
ssize_t retval;
unsigned long long msr;
char pathname[32];
int fd;
sprintf(pathname, "/dev/cpu/%d/msr", cpu);
fd = open(pathname, O_RDONLY);
if (fd < 0) {
perror(pathname);
need_reinitialize = 1;
return 0;
}
retval = pread(fd, &msr, sizeof msr, offset);
if (retval != sizeof msr) {
fprintf(stderr, "cpu%d pread(..., 0x%zx) = %jd\n",
cpu, offset, retval);
exit(-2);
}
if (fd < 0)
return -1;
retval = pread(fd, msr, sizeof *msr, offset);
close(fd);
return msr;
if (retval != sizeof *msr)
return -1;
return 0;
}
void print_header(void)
......@@ -506,36 +499,51 @@ void compute_average(struct counters *delta, struct counters *avg)
free(sum);
}
void get_counters(struct counters *cnt)
int get_counters(struct counters *cnt)
{
for ( ; cnt; cnt = cnt->next) {
if (cpu_migrate(cnt->cpu)) {
need_reinitialize = 1;
return;
if (cpu_migrate(cnt->cpu))
return -1;
if (get_msr(cnt->cpu, MSR_TSC, &cnt->tsc))
return -1;
if (has_aperf) {
if (get_msr(cnt->cpu, MSR_APERF, &cnt->aperf))
return -1;
if (get_msr(cnt->cpu, MSR_MPERF, &cnt->mperf))
return -1;
}
if (do_nhm_cstates) {
if (get_msr(cnt->cpu, MSR_CORE_C3_RESIDENCY, &cnt->c3))
return -1;
if (get_msr(cnt->cpu, MSR_CORE_C6_RESIDENCY, &cnt->c6))
return -1;
}
cnt->tsc = get_msr(cnt->cpu, MSR_TSC);
if (do_nhm_cstates)
cnt->c3 = get_msr(cnt->cpu, MSR_CORE_C3_RESIDENCY);
if (do_nhm_cstates)
cnt->c6 = get_msr(cnt->cpu, MSR_CORE_C6_RESIDENCY);
if (do_snb_cstates)
cnt->c7 = get_msr(cnt->cpu, MSR_CORE_C7_RESIDENCY);
if (has_aperf)
cnt->aperf = get_msr(cnt->cpu, MSR_APERF);
if (has_aperf)
cnt->mperf = get_msr(cnt->cpu, MSR_MPERF);
if (do_snb_cstates)
cnt->pc2 = get_msr(cnt->cpu, MSR_PKG_C2_RESIDENCY);
if (do_nhm_cstates)
cnt->pc3 = get_msr(cnt->cpu, MSR_PKG_C3_RESIDENCY);
if (do_nhm_cstates)
cnt->pc6 = get_msr(cnt->cpu, MSR_PKG_C6_RESIDENCY);
if (do_snb_cstates)
cnt->pc7 = get_msr(cnt->cpu, MSR_PKG_C7_RESIDENCY);
if (get_msr(cnt->cpu, MSR_CORE_C7_RESIDENCY, &cnt->c7))
return -1;
if (do_nhm_cstates) {
if (get_msr(cnt->cpu, MSR_PKG_C3_RESIDENCY, &cnt->pc3))
return -1;
if (get_msr(cnt->cpu, MSR_PKG_C6_RESIDENCY, &cnt->pc6))
return -1;
}
if (do_snb_cstates) {
if (get_msr(cnt->cpu, MSR_PKG_C2_RESIDENCY, &cnt->pc2))
return -1;
if (get_msr(cnt->cpu, MSR_PKG_C7_RESIDENCY, &cnt->pc7))
return -1;
}
if (extra_msr_offset)
cnt->extra_msr = get_msr(cnt->cpu, extra_msr_offset);
if (get_msr(cnt->cpu, extra_msr_offset, &cnt->extra_msr))
return -1;
}
return 0;
}
void print_nehalem_info(void)
......@@ -546,7 +554,7 @@ void print_nehalem_info(void)
if (!do_nehalem_platform_info)
return;
msr = get_msr(0, MSR_NEHALEM_PLATFORM_INFO);
get_msr(0, MSR_NEHALEM_PLATFORM_INFO, &msr);
ratio = (msr >> 40) & 0xFF;
fprintf(stderr, "%d * %.0f = %.0f MHz max efficiency\n",
......@@ -562,7 +570,7 @@ void print_nehalem_info(void)
if (!do_nehalem_turbo_ratio_limit)
return;
msr = get_msr(0, MSR_NEHALEM_TURBO_RATIO_LIMIT);
get_msr(0, MSR_NEHALEM_TURBO_RATIO_LIMIT, &msr);
ratio = (msr >> 24) & 0xFF;
if (ratio)
......@@ -755,7 +763,7 @@ int get_core_id(int cpu)
}
/*
* run func(index, cpu) on every cpu in /proc/stat
* run func(pkg, core, cpu) on every cpu in /proc/stat
*/
int for_all_cpus(void (func)(int, int, int))
......@@ -791,20 +799,18 @@ int for_all_cpus(void (func)(int, int, int))
void re_initialize(void)
{
printf("turbostat: topology changed, re-initializing.\n");
free_all_counters();
num_cpus = for_all_cpus(alloc_new_counters);
need_reinitialize = 0;
cpu_mask_uninit();
cpu_mask_init(num_cpus);
printf("num_cpus is now %d\n", num_cpus);
printf("turbostat: re-initialized with num_cpus %d\n", num_cpus);
}
void dummy(int pkg, int core, int cpu) { return; }
/*
* check to see if a cpu came on-line
*/
void verify_num_cpus(void)
int verify_num_cpus(void)
{
int new_num_cpus;
......@@ -814,8 +820,9 @@ void verify_num_cpus(void)
if (verbose)
printf("num_cpus was %d, is now %d\n",
num_cpus, new_num_cpus);
need_reinitialize = 1;
return -1;
}
return 0;
}
void turbostat_loop()
......@@ -825,25 +832,25 @@ void turbostat_loop()
gettimeofday(&tv_even, (struct timezone *)NULL);
while (1) {
verify_num_cpus();
if (need_reinitialize) {
if (verify_num_cpus()) {
re_initialize();
goto restart;
}
sleep(interval_sec);
get_counters(cnt_odd);
if (get_counters(cnt_odd)) {
re_initialize();
goto restart;
}
gettimeofday(&tv_odd, (struct timezone *)NULL);
compute_delta(cnt_odd, cnt_even, cnt_delta);
timersub(&tv_odd, &tv_even, &tv_delta);
compute_average(cnt_delta, cnt_average);
print_counters(cnt_delta);
if (need_reinitialize) {
sleep(interval_sec);
if (get_counters(cnt_even)) {
re_initialize();
goto restart;
}
sleep(interval_sec);
get_counters(cnt_even);
gettimeofday(&tv_even, (struct timezone *)NULL);
compute_delta(cnt_even, cnt_odd, cnt_delta);
timersub(&tv_even, &tv_odd, &tv_delta);
......
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