Author: mmacy Date: Fri Sep 14 01:30:05 2018 New Revision: 338677 URL: https://svnweb.freebsd.org/changeset/base/338677
Log: hwpmc: set default rate if event description lacks one / filter rate against misuse Not all event descriptions have a sample rate (such as inst_retired.any) this will restore the legacy behavior of using 65536 in that case. It also prevents accidental API misuse that could lead to panic. PR: 230985 Reported by: markj Reviewed by: markj Approved by: re (gjb) Sponsored by: Limelight Networks Differential Revision: https://reviews.freebsd.org/D16958 Modified: head/lib/libpmc/libpmc_pmu_util.c head/sys/dev/hwpmc/hwpmc_mod.c Modified: head/lib/libpmc/libpmc_pmu_util.c ============================================================================== --- head/lib/libpmc/libpmc_pmu_util.c Fri Sep 14 01:11:10 2018 (r338676) +++ head/lib/libpmc/libpmc_pmu_util.c Fri Sep 14 01:30:05 2018 (r338677) @@ -237,6 +237,7 @@ pmu_parse_event(struct pmu_event_desc *ped, const char return (ENOMEM); r = event; bzero(ped, sizeof(*ped)); + ped->ped_period = DEFAULT_SAMPLE_COUNT; ped->ped_umask = -1; while ((kvp = strsep(&event, ",")) != NULL) { key = strsep(&kvp, "="); Modified: head/sys/dev/hwpmc/hwpmc_mod.c ============================================================================== --- head/sys/dev/hwpmc/hwpmc_mod.c Fri Sep 14 01:11:10 2018 (r338676) +++ head/sys/dev/hwpmc/hwpmc_mod.c Fri Sep 14 01:30:05 2018 (r338677) @@ -61,6 +61,7 @@ __FBSDID("$FreeBSD$"); #include <sys/sx.h> #include <sys/sysctl.h> #include <sys/sysent.h> +#include <sys/syslog.h> #include <sys/systm.h> #include <sys/vnode.h> @@ -3942,9 +3943,16 @@ pmc_syscall_handler(struct thread *td, void *syscall_a pmc->pm_flags = pa.pm_flags; /* XXX set lower bound on sampling for process counters */ - if (PMC_IS_SAMPLING_MODE(mode)) - pmc->pm_sc.pm_reloadcount = pa.pm_count; - else + if (PMC_IS_SAMPLING_MODE(mode)) { + /* + * Don't permit requested sample rate to be less than 1000 + */ + if (pa.pm_count < 1000) + log(LOG_WARNING, + "pmcallocate: passed sample rate %ju - setting to 1000\n", + (uintmax_t)pa.pm_count); + pmc->pm_sc.pm_reloadcount = MAX(1000, pa.pm_count); + } else pmc->pm_sc.pm_initial = pa.pm_count; /* switch thread to CPU 'cpu' */ @@ -4460,9 +4468,16 @@ pmc_syscall_handler(struct thread *td, void *syscall_a break; } - if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) - pm->pm_sc.pm_reloadcount = sc.pm_count; - else + if (PMC_IS_SAMPLING_MODE(PMC_TO_MODE(pm))) { + /* + * Don't permit requested sample rate to be less than 1000 + */ + if (sc.pm_count < 1000) + log(LOG_WARNING, + "pmcsetcount: passed sample rate %ju - setting to 1000\n", + (uintmax_t)sc.pm_count); + pm->pm_sc.pm_reloadcount = MAX(1000, sc.pm_count); + } else pm->pm_sc.pm_initial = sc.pm_count; } break; _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
