Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752948Ab3C0O1B (ORCPT ); Wed, 27 Mar 2013 10:27:01 -0400 Received: from merlin.infradead.org ([205.233.59.134]:46939 "EHLO merlin.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750716Ab3C0O07 (ORCPT ); Wed, 27 Mar 2013 10:26:59 -0400 Message-ID: <1364394409.5053.78.camel@laptop> Subject: Re: [PATCH v2] perf: add callgrind conversion tool From: Peter Zijlstra To: Roberto Vitillo Cc: linux-kernel@vger.kernel.org, paulus@samba.org, mingo@redhat.com, acme@ghostprotocols.net, namhyung@kernel.org Date: Wed, 27 Mar 2013 15:26:49 +0100 In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.2-0ubuntu0.1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 28120 Lines: 1339 This sort of reminds me of another little proglet I have lying about that might need a home.. --- /* * Library to hook into code compiled with -finstrument-functions it will * record function arcs (call_fn, this_fn) as well as the sum of whatever event * is being measured over that function. * * Copyright (C) 2011 Red Hat, Inc., Peter Zijlstra * * This file is copyrighted under the GPLv2 License (and not any later version). * * SuperFastHash under LGPLv2.1 (http://www.azillionmonkeys.com/qed/hash.html) * * Compilation example: * gcc -shared -fPIC profviz.c -o profviz.so -lpthread -ldl -lelf * * Usage example: * LD_PRELOAD=./profviz.so your_program */ #define _GNU_SOURCE #include "util/util.h" #include "perf.h" #include "util/parse-events.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define barrier() asm volatile("" ::: "memory") static u64 rdpmc(unsigned int counter) { unsigned int low, high; asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter)); return low | ((u64)high) << 32; } static u64 rdtsc(void) { unsigned int low, high; asm volatile("rdtsc" : "=a" (low), "=d" (high)); return low | ((u64)high) << 32; } static u64 mmap_read_self(void *addr) { struct perf_event_mmap_page *pc = addr; u32 seq, idx, time_mult = 0, time_shift = 0, width = 0; u64 count, cyc = 0, time_offset = 0, enabled, running, delta; s64 pmc = 0; do { seq = pc->lock; barrier(); enabled = pc->time_enabled; running = pc->time_running; if (pc->cap_usr_time && enabled != running) { cyc = rdtsc(); time_mult = pc->time_mult; time_shift = pc->time_shift; time_offset = pc->time_offset; } idx = pc->index; count = pc->offset; if (pc->cap_usr_rdpmc && idx) { width = pc->pmc_width; pmc = rdpmc(idx - 1); } barrier(); } while (pc->lock != seq); if (idx) { pmc <<= 64 - width; pmc >>= 64 - width; /* shift right signed */ count += pmc; } if (enabled != running) { u64 quot, rem; quot = (cyc >> time_shift); rem = cyc & ((1 << time_shift) - 1); delta = time_offset + quot * time_mult + ((rem * time_mult) >> time_shift); enabled += delta; if (idx) running += delta; quot = count / running; rem = count % running; count = quot * enabled + (rem * enabled) / running; } return count; } static int (*pthread_create_orig)(pthread_t *__restrict, __const pthread_attr_t *__restrict, void *(*)(void *), void *__restrict) = NULL; static struct perf_event_attr perf_attr = { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, .exclude_kernel = 1, }; struct prof_arc { void *call_fn; void *this_fn; uint64_t count; }; struct prof_fn { void *this_fn; uint64_t count; }; #define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8) \ +(uint32_t)(((const uint8_t *)(d))[0]) ) static uint32_t SuperFastHash (const char * data, int len, uint32_t hash) { uint32_t tmp; int rem; if (len <= 0 || data == NULL) return 0; rem = len & 3; len >>= 2; /* Main loop */ for (;len > 0; len--) { hash += get16bits (data); tmp = (get16bits (data+2) << 11) ^ hash; hash = (hash << 16) ^ tmp; data += 2*sizeof (uint16_t); hash += hash >> 11; } /* Handle end cases */ switch (rem) { case 3: hash += get16bits (data); hash ^= hash << 16; hash ^= data[sizeof (uint16_t)] << 18; hash += hash >> 11; break; case 2: hash += get16bits (data); hash ^= hash << 11; hash += hash >> 17; break; case 1: hash += *data; hash ^= hash << 10; hash += hash >> 1; } /* Force "avalanching" of final 127 bits */ hash ^= hash << 3; hash += hash >> 5; hash ^= hash << 4; hash += hash >> 17; hash ^= hash << 25; hash += hash >> 6; return hash; } void die(const char *err, ...) { va_list params; va_start(params, err); vfprintf(stderr, err, params); va_end(params); exit(-1); } #define HASH_TABLE_SIZE 16384 #define AVG_STACK_DEPTH 8 #define ARC_HASH_SIZE (HASH_TABLE_SIZE * AVG_STACK_DEPTH) static struct prof_arc prof_arc_hash[ARC_HASH_SIZE]; static pthread_mutex_t prof_arc_lock; #define FN_HASH_SIZE (HASH_TABLE_SIZE) static struct prof_fn prof_fn_hash[FN_HASH_SIZE]; static pthread_mutex_t prof_fn_lock; #define HASH_INIT 0x9e370001UL #define HASH_CHAIN 16 static inline void * prof_hash_find(void *hash_base, const size_t hash_size, const void *key, const size_t key_size, const size_t entry_size, pthread_mutex_t *lock) { uint32_t hash = HASH_INIT; void *entry = NULL; int i, j; for (i = 0; i < HASH_CHAIN; i++) { hash = SuperFastHash(key, key_size, hash); entry = hash_base + entry_size * (hash % FN_HASH_SIZE); if (!memcmp(entry, key, key_size)) return entry; for (j = 0; j < key_size; j++) { if (*((char *)entry + j)) goto next_1; } goto found_empty; next_1: continue; } die("fn_hash too full"); found_empty: hash = HASH_INIT; pthread_mutex_lock(lock); for (i = 0; i < HASH_CHAIN; i++) { hash = SuperFastHash(key, key_size, hash); entry = hash_base + entry_size * (hash % FN_HASH_SIZE); if (!memcmp(entry, key, key_size)) goto unlock; for (j = 0; j < key_size; j++) { if (*((char *)entry + j)) goto next_2; } memcpy(entry, key, key_size); goto unlock; next_2: continue; } die("fn_hash too full (locked)"); unlock: pthread_mutex_unlock(lock); return entry; } static struct prof_fn *prof_fn_find(void *this_fn) { return prof_hash_find(prof_fn_hash, FN_HASH_SIZE, &this_fn, sizeof(this_fn), sizeof(struct prof_fn), &prof_fn_lock); } static struct prof_arc *prof_arc_find(void *this_fn, void *call_fn) { struct prof_arc arc = { .this_fn = this_fn, .call_fn = call_fn, }; return prof_hash_find(prof_arc_hash, ARC_HASH_SIZE, &arc, 2*sizeof(void *), sizeof(struct prof_arc), &prof_arc_lock); } static unsigned long page_size; struct prof_stack { struct prof_arc *arc; struct prof_fn *fn; uint64_t stamp; }; static __thread struct prof_stack prof_stack[128]; static __thread int prof_stack_idx = 0; static __thread void *perf_event; static void thread_init(void) { int fd; fd = sys_perf_event_open(&perf_attr, 0, -1, -1, 0); if (fd < 0) die("failed to create perf_event"); perf_event = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0); if (perf_event == (void *)(-1)) die("failed to mmap perf_event"); close(fd); prof_stack_idx = 0; } static u64 first_count; void prof_init(void) __attribute__((constructor)); void prof_init(void) { char *event_str; page_size = sysconf(_SC_PAGESIZE); pthread_create_orig = dlsym(RTLD_NEXT, "pthread_create"); if (!pthread_create_orig) { char *error = dlerror(); if (!error) error = "pthread_create is NULL"; die("%s\n", error); } memset(prof_arc_hash, 0, sizeof(prof_arc_hash)); pthread_mutex_init(&prof_arc_lock, NULL); memset(prof_fn_hash, 0, sizeof(prof_fn_hash)); pthread_mutex_init(&prof_fn_lock, NULL); event_str = getenv("PROF_EVENT"); if (event_str) /* perf_attr = parse_attr_crap(event_str); */ ; thread_init(); /* main thread */ first_count = mmap_read_self(perf_event); } struct prof_symbol { void *addr; unsigned long size; const char *name; }; static struct prof_symbol *prof_symbols; static unsigned long prof_nr_symbols; static void prof_gelf(const char *name, void (*func)(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *data), void *data) { Elf *elf; Elf_Scn *scn = NULL; GElf_Shdr shdr; int fd; elf_version(EV_CURRENT); fd = open(name, O_RDONLY); elf = elf_begin(fd, ELF_C_READ, NULL); while ((scn = elf_nextscn(elf, scn)) != NULL) { gelf_getshdr(scn, &shdr); if (shdr.sh_type == SHT_SYMTAB) { func(elf, scn, &shdr, data); } } elf_end(elf); close(fd); } static void prof_gelf_nr_symbols(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *data) { unsigned long *nr_symbols = data; unsigned long count; count = shdr->sh_size / shdr->sh_entsize; *nr_symbols += count; } static int prof_count_symbols(struct dl_phdr_info *info, size_t size, void *data) { prof_gelf(info->dlpi_name, prof_gelf_nr_symbols, data); return 0; } static void prof_gelf_load_symbols(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *_info) { struct dl_phdr_info *info = _info; unsigned long count = shdr->sh_size / shdr->sh_entsize; unsigned long i; Elf_Data *data; data = elf_getdata(scn, NULL); for (i = 0; i < count; i++) { GElf_Sym sym; char *name; struct prof_symbol *symbol = &prof_symbols[prof_nr_symbols]; gelf_getsym(data, i, &sym); if (GELF_ST_TYPE(sym.st_info) != STT_FUNC) continue; if (!sym.st_size) continue; name = elf_strptr(elf, shdr->sh_link, sym.st_name); if (!name) continue; symbol->name = strdup(name); symbol->addr = (void *)(sym.st_value + info->dlpi_addr); symbol->size = sym.st_size; prof_nr_symbols++; } } static int prof_load_symbols(struct dl_phdr_info *info, size_t size, void *data) { prof_gelf(info->dlpi_name, prof_gelf_load_symbols, info); return 0; } static int prof_cmp_symbol(const void *_a, const void *_b) { const struct prof_symbol *a = _a, *b = _b; if (a->addr < b->addr) return -1; if (a->addr > b->addr) return 1; return 0; } static void load_symbols(void) { unsigned long nr_symbols = 0; struct dl_phdr_info dl_info = { .dlpi_name = "/proc/self/exe", .dlpi_addr = 0, }; prof_count_symbols(&dl_info, sizeof(dl_info), &nr_symbols); dl_iterate_phdr(prof_count_symbols, &nr_symbols); prof_symbols = calloc(nr_symbols, sizeof(struct prof_symbol)); prof_load_symbols(&dl_info, sizeof(dl_info), NULL); dl_iterate_phdr(prof_load_symbols, NULL); qsort(prof_symbols, prof_nr_symbols, sizeof(struct prof_symbol), prof_cmp_symbol); } static struct prof_symbol *find_symbol(void *addr) { struct prof_symbol *sym; unsigned long l, u, i; l = 0; u = prof_nr_symbols; while (l < u) { i = (l + u) / 2; sym = &prof_symbols[i]; if (addr >= sym->addr && addr < sym->addr + sym->size) return sym; if (addr < sym->addr) u = i; else l = i + 1; } return NULL; } void prof_exit(void) __attribute__((destructor)); void prof_exit(void) { FILE *file; int i; int64_t max_fn_count = 0; load_symbols(); file = fopen("prof.dot", "w"); if (!file) die("failed to create output file"); fprintf(file, "#\n# first count: %lu\n#\n", first_count); /* * Maybe replace "profile" with the argv */ fprintf(file, "digraph profile {\n"); for (i = 0; i < ARC_HASH_SIZE; i++) { struct prof_arc *arc = &prof_arc_hash[i]; struct prof_symbol *c_sym, *t_sym; struct prof_fn *c; double p; if (!(arc->call_fn && arc->this_fn)) continue; c_sym = find_symbol(arc->call_fn); t_sym = find_symbol(arc->this_fn); if (!c_sym || !t_sym) die("symbols missing"); c = prof_fn_find(c_sym->addr); if (!c) die("fn_hash|symtab borken"); p = (double)arc->count / (double)c->count; fprintf(file, " \"%s\" -> \"%s\" [label=\"%f\", color=\"%.3f %.3f %.3f\"]\n", c_sym->name, t_sym->name, 100.0 * p, 0.33, 1.0, p); } for (i = 0; i < ARC_HASH_SIZE; i++) { struct prof_arc *arc = &prof_arc_hash[i]; struct prof_symbol *c_sym; struct prof_fn *c; double p; if (!(arc->call_fn && arc->this_fn)) continue; c_sym = find_symbol(arc->call_fn); c = prof_fn_find(c_sym->addr); c->count -= arc->count; } for (i = 0; i < FN_HASH_SIZE; i++) { struct prof_fn *fn = &prof_fn_hash[i]; struct prof_symbol *s; if (!fn->this_fn) continue; if ((int64_t)fn->count > max_fn_count) max_fn_count = fn->count; s = find_symbol(fn->this_fn); // fprintf(file, "# %s %ld\n", s->name, fn->count); } for (i = 0; i < FN_HASH_SIZE; i++) { struct prof_fn *fn = &prof_fn_hash[i]; struct prof_symbol *s; double p; if (!fn->this_fn) continue; s = find_symbol(fn->this_fn); p = (double)fn->count / (double)max_fn_count; fprintf(file, " \"%s\" [color=\"%.3f %.3f %.3f\"]\n", s->name, 0.0, 1.0, p); } fprintf(file, "}\n"); fflush(file); fclose(file); } struct tramp_data { void *(*func)(void *); void *arg; pthread_mutex_t lock; pthread_cond_t wait; }; static void *tramp_func(void *data) { struct tramp_data *tramp_data = data; void *(*func)(void *) = tramp_data->func; void *arg = tramp_data->arg; void *ret; thread_init(); pthread_mutex_lock(&tramp_data->lock); pthread_cond_signal(&tramp_data->wait); pthread_mutex_unlock(&tramp_data->lock); ret = func(arg); munmap(perf_event, page_size); return ret; } /* hijack pthread_create() */ int pthread_create(pthread_t *__restrict thread, __const pthread_attr_t *__restrict attr, void *(*func)(void *), void *__restrict arg) { struct tramp_data tramp_data = { .func = func, .arg = arg, }; int ret; pthread_cond_init(&tramp_data.wait, NULL); pthread_mutex_init(&tramp_data.lock, NULL); pthread_mutex_lock(&tramp_data.lock); ret = pthread_create_orig(thread, attr, &tramp_func, &tramp_data); if (!ret) pthread_cond_wait(&tramp_data.wait, &tramp_data.lock); pthread_mutex_unlock(&tramp_data.lock); pthread_mutex_destroy(&tramp_data.lock); pthread_cond_destroy(&tramp_data.wait); return ret; } void __cyg_profile_func_enter(void *this_fn, void *call_fn) { struct prof_stack *st = &prof_stack[prof_stack_idx++]; st->arc = prof_arc_find(this_fn, call_fn); st->fn = prof_fn_find(this_fn); st->stamp = mmap_read_self(perf_event); } void __cyg_profile_func_exit(void *this_fn, void *call_fn) { struct prof_stack *st = &prof_stack[--prof_stack_idx]; uint64_t now, delta; now = mmap_read_self(perf_event); delta = now - st->stamp; (void)__sync_fetch_and_add(&st->fn->count, delta); (void)__sync_fetch_and_add(&st->arc->count, delta); } /* * Library to hook into code compiled with -finstrument-functions it will * record function arcs (call_fn, this_fn) as well as the sum of whatever event * is being measured over that function. * * Copyright (C) 2011 Red Hat, Inc., Peter Zijlstra * * This file is copyrighted under the GPLv2 License (and not any later version). * * SuperFastHash under LGPLv2.1 (http://www.azillionmonkeys.com/qed/hash.html) * * Compilation example: * gcc -shared -fPIC profviz.c -o profviz.so -lpthread -ldl -lelf * * Usage example: * LD_PRELOAD=./profviz.so your_program */ #define _GNU_SOURCE #include "util/util.h" #include "perf.h" #include "util/parse-events.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define barrier() asm volatile("" ::: "memory") static u64 rdpmc(unsigned int counter) { unsigned int low, high; asm volatile("rdpmc" : "=a" (low), "=d" (high) : "c" (counter)); return low | ((u64)high) << 32; } static u64 rdtsc(void) { unsigned int low, high; asm volatile("rdtsc" : "=a" (low), "=d" (high)); return low | ((u64)high) << 32; } static u64 mmap_read_self(void *addr) { struct perf_event_mmap_page *pc = addr; u32 seq, idx, time_mult = 0, time_shift = 0, width = 0; u64 count, cyc = 0, time_offset = 0, enabled, running, delta; s64 pmc = 0; do { seq = pc->lock; barrier(); enabled = pc->time_enabled; running = pc->time_running; if (pc->cap_usr_time && enabled != running) { cyc = rdtsc(); time_mult = pc->time_mult; time_shift = pc->time_shift; time_offset = pc->time_offset; } idx = pc->index; count = pc->offset; if (pc->cap_usr_rdpmc && idx) { width = pc->pmc_width; pmc = rdpmc(idx - 1); } barrier(); } while (pc->lock != seq); if (idx) { pmc <<= 64 - width; pmc >>= 64 - width; /* shift right signed */ count += pmc; } if (enabled != running) { u64 quot, rem; quot = (cyc >> time_shift); rem = cyc & ((1 << time_shift) - 1); delta = time_offset + quot * time_mult + ((rem * time_mult) >> time_shift); enabled += delta; if (idx) running += delta; quot = count / running; rem = count % running; count = quot * enabled + (rem * enabled) / running; } return count; } static int (*pthread_create_orig)(pthread_t *__restrict, __const pthread_attr_t *__restrict, void *(*)(void *), void *__restrict) = NULL; static struct perf_event_attr perf_attr = { .type = PERF_TYPE_HARDWARE, .config = PERF_COUNT_HW_CPU_CYCLES, .exclude_kernel = 1, }; struct prof_arc { void *call_fn; void *this_fn; uint64_t count; }; struct prof_fn { void *this_fn; uint64_t count; }; #define get16bits(d) ((((uint32_t)(((const uint8_t *)(d))[1])) << 8) \ +(uint32_t)(((const uint8_t *)(d))[0]) ) static uint32_t SuperFastHash (const char * data, int len, uint32_t hash) { uint32_t tmp; int rem; if (len <= 0 || data == NULL) return 0; rem = len & 3; len >>= 2; /* Main loop */ for (;len > 0; len--) { hash += get16bits (data); tmp = (get16bits (data+2) << 11) ^ hash; hash = (hash << 16) ^ tmp; data += 2*sizeof (uint16_t); hash += hash >> 11; } /* Handle end cases */ switch (rem) { case 3: hash += get16bits (data); hash ^= hash << 16; hash ^= data[sizeof (uint16_t)] << 18; hash += hash >> 11; break; case 2: hash += get16bits (data); hash ^= hash << 11; hash += hash >> 17; break; case 1: hash += *data; hash ^= hash << 10; hash += hash >> 1; } /* Force "avalanching" of final 127 bits */ hash ^= hash << 3; hash += hash >> 5; hash ^= hash << 4; hash += hash >> 17; hash ^= hash << 25; hash += hash >> 6; return hash; } void die(const char *err, ...) { va_list params; va_start(params, err); vfprintf(stderr, err, params); va_end(params); exit(-1); } #define HASH_TABLE_SIZE 16384 #define AVG_STACK_DEPTH 8 #define ARC_HASH_SIZE (HASH_TABLE_SIZE * AVG_STACK_DEPTH) static struct prof_arc prof_arc_hash[ARC_HASH_SIZE]; static pthread_mutex_t prof_arc_lock; #define FN_HASH_SIZE (HASH_TABLE_SIZE) static struct prof_fn prof_fn_hash[FN_HASH_SIZE]; static pthread_mutex_t prof_fn_lock; #define HASH_INIT 0x9e370001UL #define HASH_CHAIN 16 static inline void * prof_hash_find(void *hash_base, const size_t hash_size, const void *key, const size_t key_size, const size_t entry_size, pthread_mutex_t *lock) { uint32_t hash = HASH_INIT; void *entry = NULL; int i, j; for (i = 0; i < HASH_CHAIN; i++) { hash = SuperFastHash(key, key_size, hash); entry = hash_base + entry_size * (hash % FN_HASH_SIZE); if (!memcmp(entry, key, key_size)) return entry; for (j = 0; j < key_size; j++) { if (*((char *)entry + j)) goto next_1; } goto found_empty; next_1: continue; } die("fn_hash too full"); found_empty: hash = HASH_INIT; pthread_mutex_lock(lock); for (i = 0; i < HASH_CHAIN; i++) { hash = SuperFastHash(key, key_size, hash); entry = hash_base + entry_size * (hash % FN_HASH_SIZE); if (!memcmp(entry, key, key_size)) goto unlock; for (j = 0; j < key_size; j++) { if (*((char *)entry + j)) goto next_2; } memcpy(entry, key, key_size); goto unlock; next_2: continue; } die("fn_hash too full (locked)"); unlock: pthread_mutex_unlock(lock); return entry; } static struct prof_fn *prof_fn_find(void *this_fn) { return prof_hash_find(prof_fn_hash, FN_HASH_SIZE, &this_fn, sizeof(this_fn), sizeof(struct prof_fn), &prof_fn_lock); } static struct prof_arc *prof_arc_find(void *this_fn, void *call_fn) { struct prof_arc arc = { .this_fn = this_fn, .call_fn = call_fn, }; return prof_hash_find(prof_arc_hash, ARC_HASH_SIZE, &arc, 2*sizeof(void *), sizeof(struct prof_arc), &prof_arc_lock); } static unsigned long page_size; struct prof_stack { struct prof_arc *arc; struct prof_fn *fn; uint64_t stamp; }; static __thread struct prof_stack prof_stack[128]; static __thread int prof_stack_idx = 0; static __thread void *perf_event; static void thread_init(void) { int fd; fd = sys_perf_event_open(&perf_attr, 0, -1, -1, 0); if (fd < 0) die("failed to create perf_event"); perf_event = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, 0); if (perf_event == (void *)(-1)) die("failed to mmap perf_event"); close(fd); prof_stack_idx = 0; } static u64 first_count; void prof_init(void) __attribute__((constructor)); void prof_init(void) { char *event_str; page_size = sysconf(_SC_PAGESIZE); pthread_create_orig = dlsym(RTLD_NEXT, "pthread_create"); if (!pthread_create_orig) { char *error = dlerror(); if (!error) error = "pthread_create is NULL"; die("%s\n", error); } memset(prof_arc_hash, 0, sizeof(prof_arc_hash)); pthread_mutex_init(&prof_arc_lock, NULL); memset(prof_fn_hash, 0, sizeof(prof_fn_hash)); pthread_mutex_init(&prof_fn_lock, NULL); event_str = getenv("PROF_EVENT"); if (event_str) /* perf_attr = parse_attr_crap(event_str); */ ; thread_init(); /* main thread */ first_count = mmap_read_self(perf_event); } struct prof_symbol { void *addr; unsigned long size; const char *name; }; static struct prof_symbol *prof_symbols; static unsigned long prof_nr_symbols; static void prof_gelf(const char *name, void (*func)(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *data), void *data) { Elf *elf; Elf_Scn *scn = NULL; GElf_Shdr shdr; int fd; elf_version(EV_CURRENT); fd = open(name, O_RDONLY); elf = elf_begin(fd, ELF_C_READ, NULL); while ((scn = elf_nextscn(elf, scn)) != NULL) { gelf_getshdr(scn, &shdr); if (shdr.sh_type == SHT_SYMTAB) { func(elf, scn, &shdr, data); } } elf_end(elf); close(fd); } static void prof_gelf_nr_symbols(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *data) { unsigned long *nr_symbols = data; unsigned long count; count = shdr->sh_size / shdr->sh_entsize; *nr_symbols += count; } static int prof_count_symbols(struct dl_phdr_info *info, size_t size, void *data) { prof_gelf(info->dlpi_name, prof_gelf_nr_symbols, data); return 0; } static void prof_gelf_load_symbols(Elf *elf, Elf_Scn *scn, GElf_Shdr *shdr, void *_info) { struct dl_phdr_info *info = _info; unsigned long count = shdr->sh_size / shdr->sh_entsize; unsigned long i; Elf_Data *data; data = elf_getdata(scn, NULL); for (i = 0; i < count; i++) { GElf_Sym sym; char *name; struct prof_symbol *symbol = &prof_symbols[prof_nr_symbols]; gelf_getsym(data, i, &sym); if (GELF_ST_TYPE(sym.st_info) != STT_FUNC) continue; if (!sym.st_size) continue; name = elf_strptr(elf, shdr->sh_link, sym.st_name); if (!name) continue; symbol->name = strdup(name); symbol->addr = (void *)(sym.st_value + info->dlpi_addr); symbol->size = sym.st_size; prof_nr_symbols++; } } static int prof_load_symbols(struct dl_phdr_info *info, size_t size, void *data) { prof_gelf(info->dlpi_name, prof_gelf_load_symbols, info); return 0; } static int prof_cmp_symbol(const void *_a, const void *_b) { const struct prof_symbol *a = _a, *b = _b; if (a->addr < b->addr) return -1; if (a->addr > b->addr) return 1; return 0; } static void load_symbols(void) { unsigned long nr_symbols = 0; struct dl_phdr_info dl_info = { .dlpi_name = "/proc/self/exe", .dlpi_addr = 0, }; prof_count_symbols(&dl_info, sizeof(dl_info), &nr_symbols); dl_iterate_phdr(prof_count_symbols, &nr_symbols); prof_symbols = calloc(nr_symbols, sizeof(struct prof_symbol)); prof_load_symbols(&dl_info, sizeof(dl_info), NULL); dl_iterate_phdr(prof_load_symbols, NULL); qsort(prof_symbols, prof_nr_symbols, sizeof(struct prof_symbol), prof_cmp_symbol); } static struct prof_symbol *find_symbol(void *addr) { struct prof_symbol *sym; unsigned long l, u, i; l = 0; u = prof_nr_symbols; while (l < u) { i = (l + u) / 2; sym = &prof_symbols[i]; if (addr >= sym->addr && addr < sym->addr + sym->size) return sym; if (addr < sym->addr) u = i; else l = i + 1; } return NULL; } void prof_exit(void) __attribute__((destructor)); void prof_exit(void) { FILE *file; int i; int64_t max_fn_count = 0; load_symbols(); file = fopen("prof.dot", "w"); if (!file) die("failed to create output file"); fprintf(file, "#\n# first count: %lu\n#\n", first_count); /* * Maybe replace "profile" with the argv */ fprintf(file, "digraph profile {\n"); for (i = 0; i < ARC_HASH_SIZE; i++) { struct prof_arc *arc = &prof_arc_hash[i]; struct prof_symbol *c_sym, *t_sym; struct prof_fn *c; double p; if (!(arc->call_fn && arc->this_fn)) continue; c_sym = find_symbol(arc->call_fn); t_sym = find_symbol(arc->this_fn); if (!c_sym || !t_sym) die("symbols missing"); c = prof_fn_find(c_sym->addr); if (!c) die("fn_hash|symtab borken"); p = (double)arc->count / (double)c->count; fprintf(file, " \"%s\" -> \"%s\" [label=\"%f\", color=\"%.3f %.3f %.3f\"]\n", c_sym->name, t_sym->name, 100.0 * p, 0.33, 1.0, p); } for (i = 0; i < ARC_HASH_SIZE; i++) { struct prof_arc *arc = &prof_arc_hash[i]; struct prof_symbol *c_sym; struct prof_fn *c; double p; if (!(arc->call_fn && arc->this_fn)) continue; c_sym = find_symbol(arc->call_fn); c = prof_fn_find(c_sym->addr); c->count -= arc->count; } for (i = 0; i < FN_HASH_SIZE; i++) { struct prof_fn *fn = &prof_fn_hash[i]; struct prof_symbol *s; if (!fn->this_fn) continue; if ((int64_t)fn->count > max_fn_count) max_fn_count = fn->count; s = find_symbol(fn->this_fn); // fprintf(file, "# %s %ld\n", s->name, fn->count); } for (i = 0; i < FN_HASH_SIZE; i++) { struct prof_fn *fn = &prof_fn_hash[i]; struct prof_symbol *s; double p; if (!fn->this_fn) continue; s = find_symbol(fn->this_fn); p = (double)fn->count / (double)max_fn_count; fprintf(file, " \"%s\" [color=\"%.3f %.3f %.3f\"]\n", s->name, 0.0, 1.0, p); } fprintf(file, "}\n"); fflush(file); fclose(file); } struct tramp_data { void *(*func)(void *); void *arg; pthread_mutex_t lock; pthread_cond_t wait; }; static void *tramp_func(void *data) { struct tramp_data *tramp_data = data; void *(*func)(void *) = tramp_data->func; void *arg = tramp_data->arg; void *ret; thread_init(); pthread_mutex_lock(&tramp_data->lock); pthread_cond_signal(&tramp_data->wait); pthread_mutex_unlock(&tramp_data->lock); ret = func(arg); munmap(perf_event, page_size); return ret; } /* hijack pthread_create() */ int pthread_create(pthread_t *__restrict thread, __const pthread_attr_t *__restrict attr, void *(*func)(void *), void *__restrict arg) { struct tramp_data tramp_data = { .func = func, .arg = arg, }; int ret; pthread_cond_init(&tramp_data.wait, NULL); pthread_mutex_init(&tramp_data.lock, NULL); pthread_mutex_lock(&tramp_data.lock); ret = pthread_create_orig(thread, attr, &tramp_func, &tramp_data); if (!ret) pthread_cond_wait(&tramp_data.wait, &tramp_data.lock); pthread_mutex_unlock(&tramp_data.lock); pthread_mutex_destroy(&tramp_data.lock); pthread_cond_destroy(&tramp_data.wait); return ret; } void __cyg_profile_func_enter(void *this_fn, void *call_fn) { struct prof_stack *st = &prof_stack[prof_stack_idx++]; st->arc = prof_arc_find(this_fn, call_fn); st->fn = prof_fn_find(this_fn); st->stamp = mmap_read_self(perf_event); } void __cyg_profile_func_exit(void *this_fn, void *call_fn) { struct prof_stack *st = &prof_stack[--prof_stack_idx]; uint64_t now, delta; now = mmap_read_self(perf_event); delta = now - st->stamp; (void)__sync_fetch_and_add(&st->fn->count, delta); (void)__sync_fetch_and_add(&st->arc->count, delta); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/