Author: freqlabs Date: Tue Aug 4 12:04:47 2020 New Revision: 363831 URL: https://svnweb.freebsd.org/changeset/base/363831
Log: MFC r363630: libpmc: Use known pmc_cpuid buffer size Use the existing PMC_CPUID_LEN to size pmc_cpuid in the kernel and various buffers for reading it in libpmc. This avoids some extra syscalls and malloc/frees. While in here, use strlcpy to copy a user-provided cpuid string instead of memcpy, to make sure we terminate the buffer. Reviewed by: mav Sponsored by: iXsystems, Inc. Differential Revision: https://reviews.freebsd.org/D25679 Modified: stable/12/lib/libpmc/libpmc_pmu_util.c stable/12/sys/dev/hwpmc/hwpmc_mod.c Directory Properties: stable/12/ (props changed) Modified: stable/12/lib/libpmc/libpmc_pmu_util.c ============================================================================== --- stable/12/lib/libpmc/libpmc_pmu_util.c Tue Aug 4 11:13:13 2020 (r363830) +++ stable/12/lib/libpmc/libpmc_pmu_util.c Tue Aug 4 12:04:47 2020 (r363831) @@ -30,6 +30,7 @@ #include <sys/types.h> #include <sys/errno.h> +#include <sys/pmc.h> #include <sys/sysctl.h> #include <stddef.h> #include <stdlib.h> @@ -89,20 +90,13 @@ static struct pmu_alias pmu_amd_alias_table[] = { static pmu_mfr_t pmu_events_mfr(void) { - char *buf; - size_t s; + char buf[PMC_CPUID_LEN]; + size_t s = sizeof(buf); pmu_mfr_t mfr; - if (sysctlbyname("kern.hwpmc.cpuid", (void *)NULL, &s, + if (sysctlbyname("kern.hwpmc.cpuid", buf, &s, (void *)NULL, 0) == -1) return (PMU_INVALID); - if ((buf = malloc(s + 1)) == NULL) - return (PMU_INVALID); - if (sysctlbyname("kern.hwpmc.cpuid", buf, &s, - (void *)NULL, 0) == -1) { - free(buf); - return (PMU_INVALID); - } if (strcasestr(buf, "AuthenticAMD") != NULL || strcasestr(buf, "HygonGenuine") != NULL) mfr = PMU_AMD; @@ -110,7 +104,6 @@ pmu_events_mfr(void) mfr = PMU_INTEL; else mfr = PMU_INVALID; - free(buf); return (mfr); } @@ -169,17 +162,14 @@ pmu_events_map_get(const char *cpuid) { regex_t re; regmatch_t pmatch[1]; - size_t s; - char buf[64]; + char buf[PMC_CPUID_LEN]; + size_t s = sizeof(buf); int match; const struct pmu_events_map *pme; if (cpuid != NULL) { - memcpy(buf, cpuid, 64); + strlcpy(buf, cpuid, s); } else { - if (sysctlbyname("kern.hwpmc.cpuid", (void *)NULL, &s, - (void *)NULL, 0) == -1) - return (NULL); if (sysctlbyname("kern.hwpmc.cpuid", buf, &s, (void *)NULL, 0) == -1) return (NULL); Modified: stable/12/sys/dev/hwpmc/hwpmc_mod.c ============================================================================== --- stable/12/sys/dev/hwpmc/hwpmc_mod.c Tue Aug 4 11:13:13 2020 (r363830) +++ stable/12/sys/dev/hwpmc/hwpmc_mod.c Tue Aug 4 12:04:47 2020 (r363831) @@ -304,7 +304,7 @@ static int pmc_callchaindepth = PMC_CALLCHAIN_DEPTH; SYSCTL_INT(_kern_hwpmc, OID_AUTO, callchaindepth, CTLFLAG_RDTUN, &pmc_callchaindepth, 0, "depth of call chain records"); -char pmc_cpuid[64]; +char pmc_cpuid[PMC_CPUID_LEN]; SYSCTL_STRING(_kern_hwpmc, OID_AUTO, cpuid, CTLFLAG_RD, pmc_cpuid, 0, "cpu version string"); #ifdef HWPMC_DEBUG _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
