Author: jtl Date: Wed Nov 18 14:52:01 2015 New Revision: 291016 URL: https://svnweb.freebsd.org/changeset/base/291016
Log: Support a wider history counter in pmcstat(8) gmon output pmcstat(8) contains an option to output sampling data in a gmon format compatible with gprof(1). Currently, it uses the default histcounter, which is an (unsigned short). With large sets of sampling data, it is possible to overflow the maximum value provided by an (unsigned short). This change adds the -e argument to pmcstat. If -e and -g are both specified, pmcstat will use a histcounter type of uint64_t. Differential Revision: https://reviews.freebsd.org/D4151 Reviewed by: jhb, bjk Approved by: gnn (mentor) MFC after: 1 month Sponsored by: Juniper Networks Modified: head/usr.sbin/pmcstat/pmcpl_gprof.c head/usr.sbin/pmcstat/pmcstat.8 head/usr.sbin/pmcstat/pmcstat.c head/usr.sbin/pmcstat/pmcstat.h Modified: head/usr.sbin/pmcstat/pmcpl_gprof.c ============================================================================== --- head/usr.sbin/pmcstat/pmcpl_gprof.c Wed Nov 18 13:19:34 2015 (r291015) +++ head/usr.sbin/pmcstat/pmcpl_gprof.c Wed Nov 18 14:52:01 2015 (r291016) @@ -74,6 +74,14 @@ __FBSDID("$FreeBSD$"); #include "pmcpl_callgraph.h" #include "pmcpl_gprof.h" +typedef uint64_t WIDEHISTCOUNTER; + +#define WIDEHISTCOUNTER_MAX UINT64_MAX +#define HISTCOUNTER_MAX USHRT_MAX +#define WIDEHISTCOUNTER_GMONTYPE ((int) 64) +#define HISTCOUNTER_GMONTYPE ((int) 0) +static int hc_sz=0; + /* * struct pmcstat_gmonfile tracks a given 'gmon.out' file. These * files are mmap()'ed in as needed. @@ -126,11 +134,13 @@ pmcstat_gmon_create_file(struct pmcstat_ gm.lpc = image->pi_start; gm.hpc = image->pi_end; - gm.ncnt = (pgf->pgf_nbuckets * sizeof(HISTCOUNTER)) + - sizeof(struct gmonhdr); + gm.ncnt = (pgf->pgf_nbuckets * hc_sz) + sizeof(struct gmonhdr); gm.version = GMONVERSION; gm.profrate = 0; /* use ticks */ - gm.histcounter_type = 0; /* compatibility with moncontrol() */ + if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC) + gm.histcounter_type = WIDEHISTCOUNTER_GMONTYPE; + else + gm.histcounter_type = HISTCOUNTER_GMONTYPE; gm.spare[0] = gm.spare[1] = 0; /* Write out the gmon header */ @@ -400,6 +410,7 @@ pmcpl_gmon_process(struct pmcstat_proces struct pmcstat_gmonfile *pgf; uintfptr_t bucket; HISTCOUNTER *hc; + WIDEHISTCOUNTER *whc; pmc_id_t pmcid; (void) nsamples; (void) usermode; (void) cpu; @@ -437,6 +448,14 @@ pmcpl_gmon_process(struct pmcstat_proces */ pgf = pmcstat_image_find_gmonfile(image, pmcid); if (pgf == NULL) { + if (hc_sz == 0) { + /* Determine the correct histcounter size. */ + if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC) + hc_sz = sizeof(WIDEHISTCOUNTER); + else + hc_sz = sizeof(HISTCOUNTER); + } + if ((pgf = calloc(1, sizeof(*pgf))) == NULL) err(EX_OSERR, "ERROR:"); @@ -448,7 +467,7 @@ pmcpl_gmon_process(struct pmcstat_proces pgf->pgf_nbuckets = (image->pi_end - image->pi_start) / FUNCTION_ALIGNMENT; /* see <machine/profile.h> */ pgf->pgf_ndatabytes = sizeof(struct gmonhdr) + - pgf->pgf_nbuckets * sizeof(HISTCOUNTER); + pgf->pgf_nbuckets * hc_sz; pgf->pgf_nsamples = 0; pgf->pgf_file = NULL; @@ -474,14 +493,25 @@ pmcpl_gmon_process(struct pmcstat_proces assert(bucket < pgf->pgf_nbuckets); - hc = (HISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata + - sizeof(struct gmonhdr)); - - /* saturating add */ - if (hc[bucket] < 0xFFFFU) /* XXX tie this to sizeof(HISTCOUNTER) */ - hc[bucket]++; - else /* mark that an overflow occurred */ - pgf->pgf_overflow = 1; + if (args.pa_flags & FLAG_DO_WIDE_GPROF_HC) { + whc = (WIDEHISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata + + sizeof(struct gmonhdr)); + + /* saturating add */ + if (whc[bucket] < WIDEHISTCOUNTER_MAX) + whc[bucket]++; + else /* mark that an overflow occurred */ + pgf->pgf_overflow = 1; + } else { + hc = (HISTCOUNTER *) ((uintptr_t) pgf->pgf_gmondata + + sizeof(struct gmonhdr)); + + /* saturating add */ + if (hc[bucket] < HISTCOUNTER_MAX) + hc[bucket]++; + else /* mark that an overflow occurred */ + pgf->pgf_overflow = 1; + } pgf->pgf_nsamples++; } Modified: head/usr.sbin/pmcstat/pmcstat.8 ============================================================================== --- head/usr.sbin/pmcstat/pmcstat.8 Wed Nov 18 13:19:34 2015 (r291015) +++ head/usr.sbin/pmcstat/pmcstat.8 Wed Nov 18 14:52:01 2015 (r291016) @@ -25,7 +25,7 @@ .\" .\" $FreeBSD$ .\" -.Dd May 27, 2015 +.Dd November 17, 2015 .Dt PMCSTAT 8 .Os .Sh NAME @@ -49,6 +49,7 @@ .Op Fl a Ar pathname .Op Fl c Ar cpu-spec .Op Fl d +.Op Fl e .Op Fl f Ar pluginopt .Op Fl g .Op Fl k Ar kerneldir @@ -260,6 +261,12 @@ The default is to measure events for the .Fl P , or .Fl S ) . +.It Fl e +Specify that the gprof profile files will use a wide history counter. +These files are produced in a format compatible with +.Xr gprof 1 . +However, other tools that cannot fully parse a BSD-style +gmon header might be unable to correctly parse these files. .It Fl f Ar pluginopt Pass option string to the active plugin. .br Modified: head/usr.sbin/pmcstat/pmcstat.c ============================================================================== --- head/usr.sbin/pmcstat/pmcstat.c Wed Nov 18 13:19:34 2015 (r291015) +++ head/usr.sbin/pmcstat/pmcstat.c Wed Nov 18 14:52:01 2015 (r291016) @@ -506,6 +506,7 @@ pmcstat_show_usage(void) "\t -a file\t print sampled PCs and callgraph to \"file\"\n" "\t -c cpu-list\t set cpus for subsequent system-wide PMCs\n" "\t -d\t\t (toggle) track descendants\n" + "\t -e\t\t use wide history counter for gprof(1) output\n" "\t -f spec\t pass \"spec\" to as plugin option\n" "\t -g\t\t produce gprof(1) compatible profiles\n" "\t -k dir\t\t set the path to the kernel\n" @@ -627,7 +628,7 @@ main(int argc, char **argv) CPU_COPY(&rootmask, &cpumask); while ((option = getopt(argc, argv, - "CD:EF:G:M:NO:P:R:S:TWa:c:df:gk:l:m:n:o:p:qr:s:t:vw:z:")) != -1) + "CD:EF:G:M:NO:P:R:S:TWa:c:def:gk:l:m:n:o:p:qr:s:t:vw:z:")) != -1) switch (option) { case 'a': /* Annotate + callgraph */ args.pa_flags |= FLAG_DO_ANNOTATE; @@ -668,6 +669,10 @@ main(int argc, char **argv) args.pa_required |= FLAG_HAS_PROCESS_PMCS; break; + case 'e': /* wide gprof metrics */ + args.pa_flags |= FLAG_DO_WIDE_GPROF_HC; + break; + case 'F': /* produce a system-wide calltree */ args.pa_flags |= FLAG_DO_CALLGRAPHS; args.pa_plugin = PMCSTAT_PL_CALLTREE; @@ -1022,6 +1027,13 @@ main(int argc, char **argv) "ERROR: options -g/-G/-m/-T require sampling PMCs or -R to be specified." ); + /* check if -e was specified without -g */ + if ((args.pa_flags & FLAG_DO_WIDE_GPROF_HC) && + !(args.pa_flags & FLAG_DO_GPROF)) + errx(EX_USAGE, +"ERROR: option -e requires gprof mode to be specified." + ); + /* check if -O was spuriously specified */ if ((args.pa_flags & FLAG_HAS_OUTPUT_LOGFILE) && (args.pa_required & FLAG_HAS_OUTPUT_LOGFILE) == 0) Modified: head/usr.sbin/pmcstat/pmcstat.h ============================================================================== --- head/usr.sbin/pmcstat/pmcstat.h Wed Nov 18 13:19:34 2015 (r291015) +++ head/usr.sbin/pmcstat/pmcstat.h Wed Nov 18 14:52:01 2015 (r291016) @@ -55,6 +55,7 @@ #define FLAG_DO_ANALYSIS 0x00020000 /* -g or -G or -m or -T */ #define FLAGS_HAS_CPUMASK 0x00040000 /* -c */ #define FLAG_HAS_DURATION 0x00080000 /* -l secs */ +#define FLAG_DO_WIDE_GPROF_HC 0x00100000 /* -e */ #define DEFAULT_SAMPLE_COUNT 65536 #define DEFAULT_WAIT_INTERVAL 5.0 _______________________________________________ [email protected] mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "[email protected]"
