[tip:perfcounters/core] perf_counter: First part of 'perf report' conversion to C + elfutils

From: tip-bot for Arnaldo Carvalho de Melo
Date: Tue May 26 2009 - 08:13:34 EST


Commit-ID: 8fa66bdcc81dd4fc2c91228074d0a4698120c5a2
Gitweb: http://git.kernel.org/tip/8fa66bdcc81dd4fc2c91228074d0a4698120c5a2
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Mon, 18 May 2009 12:45:42 -0300
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Tue, 26 May 2009 13:52:53 +0200

perf_counter: First part of 'perf report' conversion to C + elfutils

Integrate perf-report into 'perf', as builtin-report.c.

Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Acked-by: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>


---
Documentation/perf_counter/Makefile | 6 +-
Documentation/perf_counter/builtin-report.c | 751 +++++++++++++++++++++++++++
Documentation/perf_counter/builtin.h | 1 +
Documentation/perf_counter/command-list.txt | 1 +
Documentation/perf_counter/perf.c | 1 +
5 files changed, 755 insertions(+), 5 deletions(-)

diff --git a/Documentation/perf_counter/Makefile b/Documentation/perf_counter/Makefile
index 45daa72..49c601e 100644
--- a/Documentation/perf_counter/Makefile
+++ b/Documentation/perf_counter/Makefile
@@ -228,7 +228,6 @@ COMPAT_CFLAGS =
COMPAT_OBJS =
LIB_H =
LIB_OBJS =
-PROGRAMS = perf-report
SCRIPT_PERL =
SCRIPT_SH =
TEST_PROGRAMS =
@@ -315,6 +314,7 @@ LIB_OBJS += util/wrapper.o

BUILTIN_OBJS += builtin-help.o
BUILTIN_OBJS += builtin-record.o
+BUILTIN_OBJS += builtin-report.o
BUILTIN_OBJS += builtin-stat.o
BUILTIN_OBJS += builtin-top.o

@@ -811,10 +811,6 @@ clean:
$(RM) $(htmldocs).tar.gz $(manpages).tar.gz
$(RM) PERF-VERSION-FILE PERF-CFLAGS PERF-BUILD-OPTIONS

-# temporary hack:
-perf-report: perf-report.cc ../../include/linux/perf_counter.h Makefile
- g++ -g -O2 -Wall -lrt -o $@ $<
-
.PHONY: all install clean strip
.PHONY: shell_compatibility_test please_set_SHELL_PATH_to_a_more_modern_shell
.PHONY: .FORCE-PERF-VERSION-FILE TAGS tags cscope .FORCE-PERF-CFLAGS
diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c
new file mode 100644
index 0000000..864f68f
--- /dev/null
+++ b/Documentation/perf_counter/builtin-report.c
@@ -0,0 +1,751 @@
+#define _GNU_SOURCE
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <errno.h>
+#include <ctype.h>
+#include <time.h>
+#include <getopt.h>
+#include <assert.h>
+#include <search.h>
+
+#include <sys/ioctl.h>
+#include <sys/poll.h>
+#include <sys/prctl.h>
+#include <sys/wait.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#include <linux/unistd.h>
+#include <linux/types.h>
+
+#include "../../include/linux/perf_counter.h"
+#include "list.h"
+
+#define SHOW_KERNEL 1
+#define SHOW_USER 2
+#define SHOW_HV 4
+
+static char const *input_name = "output.perf";
+static int input;
+static int show_mask = SHOW_KERNEL | SHOW_USER | SHOW_HV;
+
+static unsigned long page_size;
+static unsigned long mmap_window = 32;
+
+static const char *perf_event_names[] = {
+ [PERF_EVENT_MMAP] = " PERF_EVENT_MMAP",
+ [PERF_EVENT_MUNMAP] = " PERF_EVENT_MUNMAP",
+ [PERF_EVENT_COMM] = " PERF_EVENT_COMM",
+};
+
+struct ip_event {
+ struct perf_event_header header;
+ __u64 ip;
+ __u32 pid, tid;
+};
+struct mmap_event {
+ struct perf_event_header header;
+ __u32 pid, tid;
+ __u64 start;
+ __u64 len;
+ __u64 pgoff;
+ char filename[PATH_MAX];
+};
+struct comm_event {
+ struct perf_event_header header;
+ __u32 pid,tid;
+ char comm[16];
+};
+
+typedef union event_union {
+ struct perf_event_header header;
+ struct ip_event ip;
+ struct mmap_event mmap;
+ struct comm_event comm;
+} event_t;
+
+struct section {
+ struct list_head node;
+ uint64_t start;
+ uint64_t end;
+ uint64_t offset;
+ char name[0];
+};
+
+static struct section *section__new(uint64_t start, uint64_t size,
+ uint64_t offset, char *name)
+{
+ struct section *self = malloc(sizeof(*self) + strlen(name) + 1);
+
+ if (self != NULL) {
+ self->start = start;
+ self->end = start + size;
+ self->offset = offset;
+ strcpy(self->name, name);
+ }
+
+ return self;
+}
+
+static void section__delete(struct section *self)
+{
+ free(self);
+}
+
+struct symbol {
+ struct list_head node;
+ uint64_t start;
+ uint64_t end;
+ char name[0];
+};
+
+static struct symbol *symbol__new(uint64_t start, uint64_t len, const char *name)
+{
+ struct symbol *self = malloc(sizeof(*self) + strlen(name) + 1);
+
+ if (self != NULL) {
+ self->start = start;
+ self->end = start + len;
+ strcpy(self->name, name);
+ }
+
+ return self;
+}
+
+static void symbol__delete(struct symbol *self)
+{
+ free(self);
+}
+
+static size_t symbol__fprintf(struct symbol *self, FILE *fp)
+{
+ return fprintf(fp, " %lx-%lx %s\n",
+ self->start, self->end, self->name);
+}
+
+struct dso {
+ struct list_head node;
+ struct list_head sections;
+ struct list_head syms;
+ char name[0];
+};
+
+static struct dso *dso__new(const char *name)
+{
+ struct dso *self = malloc(sizeof(*self) + strlen(name) + 1);
+
+ if (self != NULL) {
+ strcpy(self->name, name);
+ INIT_LIST_HEAD(&self->sections);
+ INIT_LIST_HEAD(&self->syms);
+ }
+
+ return self;
+}
+
+static void dso__delete_sections(struct dso *self)
+{
+ struct section *pos, *n;
+
+ list_for_each_entry_safe(pos, n, &self->sections, node)
+ section__delete(pos);
+}
+
+static void dso__delete_symbols(struct dso *self)
+{
+ struct symbol *pos, *n;
+
+ list_for_each_entry_safe(pos, n, &self->syms, node)
+ symbol__delete(pos);
+}
+
+static void dso__delete(struct dso *self)
+{
+ dso__delete_sections(self);
+ dso__delete_symbols(self);
+ free(self);
+}
+
+static void dso__insert_symbol(struct dso *self, struct symbol *sym)
+{
+ list_add_tail(&sym->node, &self->syms);
+}
+
+static struct symbol *dso__find_symbol(struct dso *self, uint64_t ip)
+{
+ if (self == NULL)
+ return NULL;
+
+ struct symbol *pos;
+
+ list_for_each_entry(pos, &self->syms, node)
+ if (ip >= pos->start && ip <= pos->end)
+ return pos;
+
+ return NULL;
+}
+
+static int dso__load(struct dso *self)
+{
+ /* FIXME */
+ return 0;
+}
+
+static size_t dso__fprintf(struct dso *self, FILE *fp)
+{
+ struct symbol *pos;
+ size_t ret = fprintf(fp, "dso: %s\n", self->name);
+
+ list_for_each_entry(pos, &self->syms, node)
+ ret += symbol__fprintf(pos, fp);
+
+ return ret;
+}
+
+static LIST_HEAD(dsos);
+static struct dso *kernel_dso;
+
+static void dsos__add(struct dso *dso)
+{
+ list_add_tail(&dso->node, &dsos);
+}
+
+static struct dso *dsos__find(const char *name)
+{
+ struct dso *pos;
+
+ list_for_each_entry(pos, &dsos, node)
+ if (strcmp(pos->name, name) == 0)
+ return pos;
+ return NULL;
+}
+
+static struct dso *dsos__findnew(const char *name)
+{
+ struct dso *dso = dsos__find(name);
+
+ if (dso == NULL) {
+ dso = dso__new(name);
+ if (dso != NULL && dso__load(dso) < 0)
+ goto out_delete_dso;
+
+ dsos__add(dso);
+ }
+
+ return dso;
+
+out_delete_dso:
+ dso__delete(dso);
+ return NULL;
+}
+
+static void dsos__fprintf(FILE *fp)
+{
+ struct dso *pos;
+
+ list_for_each_entry(pos, &dsos, node)
+ dso__fprintf(pos, fp);
+}
+
+static int load_kallsyms(void)
+{
+ kernel_dso = dso__new("[kernel]");
+ if (kernel_dso == NULL)
+ return -1;
+
+ FILE *file = fopen("/proc/kallsyms", "r");
+
+ if (file == NULL)
+ goto out_delete_dso;
+
+ char *line = NULL;
+ size_t n;
+
+ while (!feof(file)) {
+ unsigned long long start;
+ char c, symbf[4096];
+
+ if (getline(&line, &n, file) < 0)
+ break;
+
+ if (!line)
+ goto out_delete_dso;
+
+ if (sscanf(line, "%llx %c %s", &start, &c, symbf) == 3) {
+ struct symbol *sym = symbol__new(start, 0x1000000, symbf);
+
+ if (sym == NULL)
+ goto out_delete_dso;
+
+ dso__insert_symbol(kernel_dso, sym);
+ }
+ }
+
+ dsos__add(kernel_dso);
+ free(line);
+ fclose(file);
+ return 0;
+
+out_delete_dso:
+ dso__delete(kernel_dso);
+ return -1;
+}
+
+struct map {
+ struct list_head node;
+ uint64_t start;
+ uint64_t end;
+ uint64_t pgoff;
+ struct dso *dso;
+};
+
+static struct map *map__new(struct mmap_event *event)
+{
+ struct map *self = malloc(sizeof(*self));
+
+ if (self != NULL) {
+ self->start = event->start;
+ self->end = event->start + event->len;
+ self->pgoff = event->pgoff;
+
+ self->dso = dsos__findnew(event->filename);
+ if (self->dso == NULL)
+ goto out_delete;
+ }
+ return self;
+out_delete:
+ free(self);
+ return NULL;
+}
+
+static size_t map__fprintf(struct map *self, FILE *fp)
+{
+ return fprintf(fp, " %lx-%lx %lx %s\n",
+ self->start, self->end, self->pgoff, self->dso->name);
+}
+
+struct symhist {
+ struct list_head node;
+ struct dso *dso;
+ struct symbol *sym;
+ uint32_t count;
+ char level;
+};
+
+static struct symhist *symhist__new(struct symbol *sym, struct dso *dso,
+ char level)
+{
+ struct symhist *self = malloc(sizeof(*self));
+
+ if (self != NULL) {
+ self->sym = sym;
+ self->dso = dso;
+ self->level = level;
+ self->count = 0;
+ }
+
+ return self;
+}
+
+static void symhist__delete(struct symhist *self)
+{
+ free(self);
+}
+
+static bool symhist__equal(struct symhist *self, struct symbol *sym,
+ struct dso *dso, char level)
+{
+ return self->level == level && self->sym == sym && self->dso == dso;
+}
+
+static void symhist__inc(struct symhist *self)
+{
+ ++self->count;
+}
+
+static size_t symhist__fprintf(struct symhist *self, FILE *fp)
+{
+ size_t ret = fprintf(fp, "[%c] ", self->level);
+
+ if (self->level != '.')
+ ret += fprintf(fp, "%s", self->sym->name);
+ else
+ ret += fprintf(fp, "%s: %s",
+ self->dso ? self->dso->name : "<unknown",
+ self->sym ? self->sym->name : "<unknown>");
+ return ret + fprintf(fp, ": %u\n", self->count);
+}
+
+struct thread {
+ struct list_head node;
+ struct list_head maps;
+ struct list_head symhists;
+ pid_t pid;
+ char *comm;
+};
+
+static struct thread *thread__new(pid_t pid)
+{
+ struct thread *self = malloc(sizeof(*self));
+
+ if (self != NULL) {
+ self->pid = pid;
+ self->comm = NULL;
+ INIT_LIST_HEAD(&self->maps);
+ INIT_LIST_HEAD(&self->symhists);
+ }
+
+ return self;
+}
+
+static void thread__insert_symhist(struct thread *self,
+ struct symhist *symhist)
+{
+ list_add_tail(&symhist->node, &self->symhists);
+}
+
+static struct symhist *thread__symhists_find(struct thread *self,
+ struct symbol *sym,
+ struct dso *dso, char level)
+{
+ struct symhist *pos;
+
+ list_for_each_entry(pos, &self->symhists, node)
+ if (symhist__equal(pos, sym, dso, level))
+ return pos;
+
+ return NULL;
+}
+
+static int thread__symbol_incnew(struct thread *self, struct symbol *sym,
+ struct dso *dso, char level)
+{
+ struct symhist *symhist = thread__symhists_find(self, sym, dso, level);
+
+ if (symhist == NULL) {
+ symhist = symhist__new(sym, dso, level);
+ if (symhist == NULL)
+ goto out_error;
+ thread__insert_symhist(self, symhist);
+ }
+
+ symhist__inc(symhist);
+ return 0;
+out_error:
+ return -ENOMEM;
+}
+
+static int thread__set_comm(struct thread *self, const char *comm)
+{
+ self->comm = strdup(comm);
+ return self->comm ? 0 : -ENOMEM;
+}
+
+static size_t thread__maps_fprintf(struct thread *self, FILE *fp)
+{
+ struct map *pos;
+ size_t ret = 0;
+
+ list_for_each_entry(pos, &self->maps, node)
+ ret += map__fprintf(pos, fp);
+
+ return ret;
+}
+
+static size_t thread__fprintf(struct thread *self, FILE *fp)
+{
+ struct symhist *pos;
+ int ret = fprintf(fp, "thread: %d %s\n", self->pid, self->comm);
+
+ list_for_each_entry(pos, &self->symhists, node)
+ ret += symhist__fprintf(pos, fp);
+
+ return ret;
+}
+
+static LIST_HEAD(threads);
+
+static void threads__add(struct thread *thread)
+{
+ list_add_tail(&thread->node, &threads);
+}
+
+static struct thread *threads__find(pid_t pid)
+{
+ struct thread *pos;
+
+ list_for_each_entry(pos, &threads, node)
+ if (pos->pid == pid)
+ return pos;
+ return NULL;
+}
+
+static struct thread *threads__findnew(pid_t pid)
+{
+ struct thread *thread = threads__find(pid);
+
+ if (thread == NULL) {
+ thread = thread__new(pid);
+ if (thread != NULL)
+ threads__add(thread);
+ }
+
+ return thread;
+}
+
+static void thread__insert_map(struct thread *self, struct map *map)
+{
+ list_add_tail(&map->node, &self->maps);
+}
+
+static struct map *thread__find_map(struct thread *self, uint64_t ip)
+{
+ if (self == NULL)
+ return NULL;
+
+ struct map *pos;
+
+ list_for_each_entry(pos, &self->maps, node)
+ if (ip >= pos->start && ip <= pos->end)
+ return pos;
+
+ return NULL;
+}
+
+static void threads__fprintf(FILE *fp)
+{
+ struct thread *pos;
+
+ list_for_each_entry(pos, &threads, node)
+ thread__fprintf(pos, fp);
+}
+
+#if 0
+static std::string resolve_user_symbol(int pid, uint64_t ip)
+{
+ std::string sym = "<unknown>";
+
+ maps_t &m = maps[pid];
+ maps_t::const_iterator mi = m.upper_bound(map(ip));
+ if (mi == m.end())
+ return sym;
+
+ ip -= mi->start + mi->pgoff;
+
+ symbols_t &s = dsos[mi->dso].syms;
+ symbols_t::const_iterator si = s.upper_bound(symbol(ip));
+
+ sym = mi->dso + ": <unknown>";
+
+ if (si == s.begin())
+ return sym;
+ si--;
+
+ if (si->start <= ip && ip < si->end)
+ sym = mi->dso + ": " + si->name;
+#if 0
+ else if (si->start <= ip)
+ sym = mi->dso + ": ?" + si->name;
+#endif
+
+ return sym;
+}
+#endif
+
+static void display_help(void)
+{
+ printf(
+ "Usage: perf-report [<options>]\n"
+ " -i file --input=<file> # input file\n"
+ );
+
+ exit(0);
+}
+
+static void process_options(int argc, char *argv[])
+{
+ int error = 0;
+
+ for (;;) {
+ int option_index = 0;
+ /** Options for getopt */
+ static struct option long_options[] = {
+ {"input", required_argument, NULL, 'i'},
+ {"no-user", no_argument, NULL, 'u'},
+ {"no-kernel", no_argument, NULL, 'k'},
+ {"no-hv", no_argument, NULL, 'h'},
+ {NULL, 0, NULL, 0 }
+ };
+ int c = getopt_long(argc, argv, "+:i:kuh",
+ long_options, &option_index);
+ if (c == -1)
+ break;
+
+ switch (c) {
+ case 'i': input_name = strdup(optarg); break;
+ case 'k': show_mask &= ~SHOW_KERNEL; break;
+ case 'u': show_mask &= ~SHOW_USER; break;
+ case 'h': show_mask &= ~SHOW_HV; break;
+ default: error = 1; break;
+ }
+ }
+
+ if (error)
+ display_help();
+}
+
+int cmd_report(int argc, char **argv)
+{
+ unsigned long offset = 0;
+ unsigned long head = 0;
+ struct stat stat;
+ char *buf;
+ event_t *event;
+ int ret, rc = EXIT_FAILURE;
+ unsigned long total = 0;
+
+ page_size = getpagesize();
+
+ process_options(argc, argv);
+
+ input = open(input_name, O_RDONLY);
+ if (input < 0) {
+ perror("failed to open file");
+ exit(-1);
+ }
+
+ ret = fstat(input, &stat);
+ if (ret < 0) {
+ perror("failed to stat file");
+ exit(-1);
+ }
+
+ if (!stat.st_size) {
+ fprintf(stderr, "zero-sized file, nothing to do!\n");
+ exit(0);
+ }
+
+ if (load_kallsyms() < 0) {
+ perror("failed to open kallsyms");
+ return EXIT_FAILURE;
+ }
+
+remap:
+ buf = (char *)mmap(NULL, page_size * mmap_window, PROT_READ,
+ MAP_SHARED, input, offset);
+ if (buf == MAP_FAILED) {
+ perror("failed to mmap file");
+ exit(-1);
+ }
+
+more:
+ event = (event_t *)(buf + head);
+
+ if (head + event->header.size >= page_size * mmap_window) {
+ unsigned long shift = page_size * (head / page_size);
+ int ret;
+
+ ret = munmap(buf, page_size * mmap_window);
+ assert(ret == 0);
+
+ offset += shift;
+ head -= shift;
+ goto remap;
+ }
+
+
+ if (!event->header.size) {
+ fprintf(stderr, "zero-sized event at file offset %ld\n", offset + head);
+ fprintf(stderr, "skipping %ld bytes of events.\n", stat.st_size - offset - head);
+ goto done;
+ }
+
+ head += event->header.size;
+
+ if (event->header.misc & PERF_EVENT_MISC_OVERFLOW) {
+ char level;
+ int show = 0;
+ struct dso *dso = NULL;
+ struct thread *thread = threads__findnew(event->ip.pid);
+
+ if (thread == NULL)
+ goto done;
+
+ if (event->header.misc & PERF_EVENT_MISC_KERNEL) {
+ show = SHOW_KERNEL;
+ level = 'k';
+ dso = kernel_dso;
+ } else if (event->header.misc & PERF_EVENT_MISC_USER) {
+ show = SHOW_USER;
+ level = '.';
+ struct map *map = thread__find_map(thread, event->ip.ip);
+ if (map != NULL)
+ dso = map->dso;
+ } else {
+ show = SHOW_HV;
+ level = 'H';
+ }
+
+ if (show & show_mask) {
+ struct symbol *sym = dso__find_symbol(dso, event->ip.ip);
+
+ if (thread__symbol_incnew(thread, sym, dso, level))
+ goto done;
+ }
+ total++;
+ } else switch (event->header.type) {
+ case PERF_EVENT_MMAP: {
+ struct thread *thread = threads__findnew(event->mmap.pid);
+ struct map *map = map__new(&event->mmap);
+
+ if (thread == NULL || map == NULL )
+ goto done;
+ thread__insert_map(thread, map);
+ break;
+ }
+ case PERF_EVENT_COMM: {
+ struct thread *thread = threads__findnew(event->comm.pid);
+
+ if (thread == NULL ||
+ thread__set_comm(thread, event->comm.comm))
+ goto done;
+ break;
+ }
+ }
+
+ if (offset + head < stat.st_size)
+ goto more;
+
+ rc = EXIT_SUCCESS;
+done:
+ close(input);
+ //dsos__fprintf(stdout);
+ threads__fprintf(stdout);
+#if 0
+ std::map<std::string, int>::iterator hi = hist.begin();
+
+ while (hi != hist.end()) {
+ rev_hist.insert(std::pair<int, std::string>(hi->second, hi->first));
+ hist.erase(hi++);
+ }
+
+ std::multimap<int, std::string>::const_iterator ri = rev_hist.begin();
+
+ while (ri != rev_hist.end()) {
+ printf(" %5.2f %s\n", (100.0 * ri->first)/total, ri->second.c_str());
+ ri++;
+ }
+#endif
+ return rc;
+}
+
diff --git a/Documentation/perf_counter/builtin.h b/Documentation/perf_counter/builtin.h
index d32318a..5bfea57 100644
--- a/Documentation/perf_counter/builtin.h
+++ b/Documentation/perf_counter/builtin.h
@@ -16,6 +16,7 @@ extern int check_pager_config(const char *cmd);

extern int cmd_help(int argc, const char **argv, const char *prefix);
extern int cmd_record(int argc, const char **argv, const char *prefix);
+extern int cmd_report(int argc, const char **argv, const char *prefix);
extern int cmd_stat(int argc, const char **argv, const char *prefix);
extern int cmd_top(int argc, const char **argv, const char *prefix);
extern int cmd_version(int argc, const char **argv, const char *prefix);
diff --git a/Documentation/perf_counter/command-list.txt b/Documentation/perf_counter/command-list.txt
index d15210a..4390292 100644
--- a/Documentation/perf_counter/command-list.txt
+++ b/Documentation/perf_counter/command-list.txt
@@ -1,6 +1,7 @@
# List of known perf commands.
# command name category [deprecated] [common]
perf-record mainporcelain common
+perf-report mainporcelain common
perf-stat mainporcelain common
perf-top mainporcelain common

diff --git a/Documentation/perf_counter/perf.c b/Documentation/perf_counter/perf.c
index 1d6d7aa..e8a8584 100644
--- a/Documentation/perf_counter/perf.c
+++ b/Documentation/perf_counter/perf.c
@@ -250,6 +250,7 @@ static void handle_internal_command(int argc, const char **argv)
static struct cmd_struct commands[] = {
{ "help", cmd_help, 0 },
{ "record", cmd_record, 0 },
+ { "report", cmd_report, 0 },
{ "stat", cmd_stat, 0 },
{ "top", cmd_top, 0 },
{ "version", cmd_version, 0 },
--
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