From: Len Brown Date: Fri, 30 Mar 2012 02:19:58 +0000 (-0400) Subject: tools turbostat: harden against cpu online/offline X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=15aaa34654831e98dd76f7738b6c7f5d05a66430;p=openwrt%2Fstaging%2Fblogic.git 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: Len Brown --- diff --git a/tools/power/x86/turbostat/turbostat.c b/tools/power/x86/turbostat/turbostat.c index fa60872b9474..ab2f682fd44c 100644 --- a/tools/power/x86/turbostat/turbostat.c +++ b/tools/power/x86/turbostat/turbostat.c @@ -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 @@ restart: 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);