ref: 12e226ac6798412271020d42645f69138715c519
dir: /utils/kprof/kprof.c/
#include <lib9.h> #include <bio.h> #include <mach.h> enum { SpecialTotalTicks, SpecialOutsideTicks, SpecialMicroSecondsPerTick, SpecialSamples, SpecialSampleSize, SpecialSampleLogBucketSize, SpecialMax }; int pcres = 8; ulong uspertick; struct COUNTER { char *name; /* function name */ ulong time; /* ticks spent there */ }; void error(int perr, char *s) { fprint(2, "kprof: %s", s); if(perr) fprint(2, ": %r\n"); else fprint(2, "\n"); exits(s); } int compar(void *va, void *vb) { struct COUNTER *a, *b; a = (struct COUNTER *)va; b = (struct COUNTER *)vb; if(a->time < b->time) return -1; if(a->time == b->time) return 0; return 1; } ulong tickstoms(ulong ticks) { return ((vlong)ticks * uspertick) / 1000; } void main(int argc, char *argv[]) { int fd; long i, j, k, n; Dir *d; char *name; ulong *data; ulong tbase, sum; long delta; Symbol s; Biobuf outbuf; Fhdr f; struct COUNTER *cp; if(argc != 3) error(0, "usage: kprof text data"); /* * Read symbol table */ fd = open(argv[1], OREAD); if(fd < 0) error(1, argv[1]); if (!crackhdr(fd, &f)) error(1, "read text header"); if (f.type == FNONE) error(0, "text file not an a.out"); if (syminit(fd, &f) < 0) error(1, "syminit"); close(fd); /* * Read timing data */ fd = open(argv[2], OREAD); if(fd < 0) error(1, argv[2]); if((d = dirfstat(fd)) == nil) error(1, "stat"); n = d->length/sizeof(data[0]); if(n < 2) error(0, "data file too short"); data = malloc(d->length); if(data == 0) error(1, "malloc"); if(read(fd, data, d->length) < 0) error(1, "text read"); close(fd); free(d); for(i=0; i<n; i++) data[i] = beswal(data[i]); pcres = 1 << data[SpecialSampleLogBucketSize]; uspertick = data[SpecialMicroSecondsPerTick]; if (data[SpecialSampleSize] != sizeof(data[0])) error(0, "only sample size 4 supported\n"); delta = data[SpecialTotalTicks] - data[SpecialOutsideTicks]; print("total: %lud in kernel text: %lud outside kernel text: %lud\n", data[0], delta, data[1]); if(data[0] == 0) exits(0); if (!textsym(&s, 0)) error(0, "no text symbols"); tbase = s.value & ~(mach->pgsize-1); /* align down to page */ print("KTZERO %.8lux\n", tbase); /* * Accumulate counts for each function */ cp = 0; k = 0; for (i = 0, j = (s.value-tbase)/pcres+SpecialMax; j < n; i++) { name = s.name; /* save name */ if (!textsym(&s, i)) /* get next symbol */ break; sum = 0; while (j < n && j*pcres < s.value-tbase) sum += data[j++]; if (sum) { cp = realloc(cp, (k+1)*sizeof(struct COUNTER)); if (cp == 0) error(1, "realloc"); cp[k].name = name; cp[k].time = sum; k++; } } if (!k) error(0, "no counts"); cp[k].time = 0; /* "etext" can take no time */ /* * Sort by time and print */ qsort(cp, k, sizeof(struct COUNTER), compar); Binit(&outbuf, 1, OWRITE); Bprint(&outbuf, "ms %% sym\n"); while(--k>=0) Bprint(&outbuf, "%lud\t%3lud.%ld\t%s\n", tickstoms(cp[k].time), 100*cp[k].time/delta, (1000*cp[k].time/delta)%10, cp[k].name); exits(0); }