linux/tools/perf/builtin-annotate.c
Arnaldo Carvalho de Melo b91fc39f4a perf machine: Protect the machine->threads with a rwlock
In addition to using refcounts for the struct thread lifetime
management, we need to protect access to machine->threads from
concurrent access.

That happens in 'perf top', where a thread processes events, inserting
and deleting entries from that rb_tree while another thread decays
hist_entries, that end up dropping references and ultimately deleting
threads from the rb_tree and releasing its resources when no further
hist_entry (or other data structures, like in 'perf sched') references
it.

So the rule is the same for refcounts + protected trees in the kernel,
get the tree lock, find object, bump the refcount, drop the tree lock,
return, use object, drop the refcount if no more use of it is needed,
keep it if storing it in some other data structure, drop when releasing
that data structure.

I.e. pair "t = machine__find(new)_thread()" with a "thread__put(t)", and
"perf_event__preprocess_sample(&al)" with "addr_location__put(&al)".

The addr_location__put() one is because as we return references to
several data structures, we may end up adding more reference counting
for the other data structures and then we'll drop it at
addr_location__put() time.

Acked-by: David Ahern <dsahern@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-bs9rt4n0jw3hi9f3zxyy3xln@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-05-08 16:19:27 -03:00

389 lines
9.9 KiB
C

/*
* builtin-annotate.c
*
* Builtin annotate command: Analyze the perf.data input file,
* look up and read DSOs and symbol information and display
* a histogram of results, along various sorting keys.
*/
#include "builtin.h"
#include "util/util.h"
#include "util/color.h"
#include <linux/list.h>
#include "util/cache.h"
#include <linux/rbtree.h>
#include "util/symbol.h"
#include "perf.h"
#include "util/debug.h"
#include "util/evlist.h"
#include "util/evsel.h"
#include "util/annotate.h"
#include "util/event.h"
#include "util/parse-options.h"
#include "util/parse-events.h"
#include "util/thread.h"
#include "util/sort.h"
#include "util/hist.h"
#include "util/session.h"
#include "util/tool.h"
#include "util/data.h"
#include "arch/common.h"
#include <dlfcn.h>
#include <linux/bitmap.h>
struct perf_annotate {
struct perf_tool tool;
struct perf_session *session;
bool use_tui, use_stdio, use_gtk;
bool full_paths;
bool print_line;
bool skip_missing;
const char *sym_hist_filter;
const char *cpu_list;
DECLARE_BITMAP(cpu_bitmap, MAX_NR_CPUS);
};
static int perf_evsel__add_sample(struct perf_evsel *evsel,
struct perf_sample *sample __maybe_unused,
struct addr_location *al,
struct perf_annotate *ann)
{
struct hists *hists = evsel__hists(evsel);
struct hist_entry *he;
int ret;
if (ann->sym_hist_filter != NULL &&
(al->sym == NULL ||
strcmp(ann->sym_hist_filter, al->sym->name) != 0)) {
/* We're only interested in a symbol named sym_hist_filter */
if (al->sym != NULL) {
rb_erase(&al->sym->rb_node,
&al->map->dso->symbols[al->map->type]);
symbol__delete(al->sym);
}
return 0;
}
he = __hists__add_entry(hists, al, NULL, NULL, NULL, 1, 1, 0, true);
if (he == NULL)
return -ENOMEM;
ret = hist_entry__inc_addr_samples(he, evsel->idx, al->addr);
hists__inc_nr_samples(hists, true);
return ret;
}
static int process_sample_event(struct perf_tool *tool,
union perf_event *event,
struct perf_sample *sample,
struct perf_evsel *evsel,
struct machine *machine)
{
struct perf_annotate *ann = container_of(tool, struct perf_annotate, tool);
struct addr_location al;
int ret = 0;
if (perf_event__preprocess_sample(event, machine, &al, sample) < 0) {
pr_warning("problem processing %d event, skipping it.\n",
event->header.type);
return -1;
}
if (ann->cpu_list && !test_bit(sample->cpu, ann->cpu_bitmap))
goto out_put;
if (!al.filtered && perf_evsel__add_sample(evsel, sample, &al, ann)) {
pr_warning("problem incrementing symbol count, "
"skipping event\n");
ret = -1;
}
out_put:
addr_location__put(&al);
return ret;
}
static int hist_entry__tty_annotate(struct hist_entry *he,
struct perf_evsel *evsel,
struct perf_annotate *ann)
{
return symbol__tty_annotate(he->ms.sym, he->ms.map, evsel,
ann->print_line, ann->full_paths, 0, 0);
}
static void hists__find_annotations(struct hists *hists,
struct perf_evsel *evsel,
struct perf_annotate *ann)
{
struct rb_node *nd = rb_first(&hists->entries), *next;
int key = K_RIGHT;
while (nd) {
struct hist_entry *he = rb_entry(nd, struct hist_entry, rb_node);
struct annotation *notes;
if (he->ms.sym == NULL || he->ms.map->dso->annotate_warned)
goto find_next;
notes = symbol__annotation(he->ms.sym);
if (notes->src == NULL) {
find_next:
if (key == K_LEFT)
nd = rb_prev(nd);
else
nd = rb_next(nd);
continue;
}
if (use_browser == 2) {
int ret;
int (*annotate)(struct hist_entry *he,
struct perf_evsel *evsel,
struct hist_browser_timer *hbt);
annotate = dlsym(perf_gtk_handle,
"hist_entry__gtk_annotate");
if (annotate == NULL) {
ui__error("GTK browser not found!\n");
return;
}
ret = annotate(he, evsel, NULL);
if (!ret || !ann->skip_missing)
return;
/* skip missing symbols */
nd = rb_next(nd);
} else if (use_browser == 1) {
key = hist_entry__tui_annotate(he, evsel, NULL);
switch (key) {
case -1:
if (!ann->skip_missing)
return;
/* fall through */
case K_RIGHT:
next = rb_next(nd);
break;
case K_LEFT:
next = rb_prev(nd);
break;
default:
return;
}
if (next != NULL)
nd = next;
} else {
hist_entry__tty_annotate(he, evsel, ann);
nd = rb_next(nd);
/*
* Since we have a hist_entry per IP for the same
* symbol, free he->ms.sym->src to signal we already
* processed this symbol.
*/
zfree(&notes->src);
}
}
}
static int __cmd_annotate(struct perf_annotate *ann)
{
int ret;
struct perf_session *session = ann->session;
struct perf_evsel *pos;
u64 total_nr_samples;
machines__set_symbol_filter(&session->machines, symbol__annotate_init);
if (ann->cpu_list) {
ret = perf_session__cpu_bitmap(session, ann->cpu_list,
ann->cpu_bitmap);
if (ret)
goto out;
}
if (!objdump_path) {
ret = perf_session_env__lookup_objdump(&session->header.env);
if (ret)
goto out;
}
ret = perf_session__process_events(session);
if (ret)
goto out;
if (dump_trace) {
perf_session__fprintf_nr_events(session, stdout);
perf_evlist__fprintf_nr_events(session->evlist, stdout);
goto out;
}
if (verbose > 3)
perf_session__fprintf(session, stdout);
if (verbose > 2)
perf_session__fprintf_dsos(session, stdout);
total_nr_samples = 0;
evlist__for_each(session->evlist, pos) {
struct hists *hists = evsel__hists(pos);
u32 nr_samples = hists->stats.nr_events[PERF_RECORD_SAMPLE];
if (nr_samples > 0) {
total_nr_samples += nr_samples;
hists__collapse_resort(hists, NULL);
hists__output_resort(hists, NULL);
if (symbol_conf.event_group &&
!perf_evsel__is_group_leader(pos))
continue;
hists__find_annotations(hists, pos, ann);
}
}
if (total_nr_samples == 0) {
ui__error("The %s file has no samples!\n", session->file->path);
goto out;
}
if (use_browser == 2) {
void (*show_annotations)(void);
show_annotations = dlsym(perf_gtk_handle,
"perf_gtk__show_annotations");
if (show_annotations == NULL) {
ui__error("GTK browser not found!\n");
goto out;
}
show_annotations();
}
out:
return ret;
}
static const char * const annotate_usage[] = {
"perf annotate [<options>]",
NULL
};
int cmd_annotate(int argc, const char **argv, const char *prefix __maybe_unused)
{
struct perf_annotate annotate = {
.tool = {
.sample = process_sample_event,
.mmap = perf_event__process_mmap,
.mmap2 = perf_event__process_mmap2,
.comm = perf_event__process_comm,
.exit = perf_event__process_exit,
.fork = perf_event__process_fork,
.ordered_events = true,
.ordering_requires_timestamps = true,
},
};
struct perf_data_file file = {
.path = input_name,
.mode = PERF_DATA_MODE_READ,
};
const struct option options[] = {
OPT_STRING('i', "input", &input_name, "file",
"input file name"),
OPT_STRING('d', "dsos", &symbol_conf.dso_list_str, "dso[,dso...]",
"only consider symbols in these dsos"),
OPT_STRING('s', "symbol", &annotate.sym_hist_filter, "symbol",
"symbol to annotate"),
OPT_BOOLEAN('f', "force", &file.force, "don't complain, do it"),
OPT_INCR('v', "verbose", &verbose,
"be more verbose (show symbol address, etc)"),
OPT_BOOLEAN('D', "dump-raw-trace", &dump_trace,
"dump raw trace in ASCII"),
OPT_BOOLEAN(0, "gtk", &annotate.use_gtk, "Use the GTK interface"),
OPT_BOOLEAN(0, "tui", &annotate.use_tui, "Use the TUI interface"),
OPT_BOOLEAN(0, "stdio", &annotate.use_stdio, "Use the stdio interface"),
OPT_STRING('k', "vmlinux", &symbol_conf.vmlinux_name,
"file", "vmlinux pathname"),
OPT_BOOLEAN('m', "modules", &symbol_conf.use_modules,
"load module symbols - WARNING: use only with -k and LIVE kernel"),
OPT_BOOLEAN('l', "print-line", &annotate.print_line,
"print matching source lines (may be slow)"),
OPT_BOOLEAN('P', "full-paths", &annotate.full_paths,
"Don't shorten the displayed pathnames"),
OPT_BOOLEAN(0, "skip-missing", &annotate.skip_missing,
"Skip symbols that cannot be annotated"),
OPT_STRING('C', "cpu", &annotate.cpu_list, "cpu", "list of cpus to profile"),
OPT_STRING(0, "symfs", &symbol_conf.symfs, "directory",
"Look for files with symbols relative to this directory"),
OPT_BOOLEAN(0, "source", &symbol_conf.annotate_src,
"Interleave source code with assembly code (default)"),
OPT_BOOLEAN(0, "asm-raw", &symbol_conf.annotate_asm_raw,
"Display raw encoding of assembly instructions (default)"),
OPT_STRING('M', "disassembler-style", &disassembler_style, "disassembler style",
"Specify disassembler style (e.g. -M intel for intel syntax)"),
OPT_STRING(0, "objdump", &objdump_path, "path",
"objdump binary to use for disassembly and annotations"),
OPT_BOOLEAN(0, "group", &symbol_conf.event_group,
"Show event group information together"),
OPT_END()
};
int ret = hists__init();
if (ret < 0)
return ret;
argc = parse_options(argc, argv, options, annotate_usage, 0);
if (annotate.use_stdio)
use_browser = 0;
else if (annotate.use_tui)
use_browser = 1;
else if (annotate.use_gtk)
use_browser = 2;
setup_browser(true);
annotate.session = perf_session__new(&file, false, &annotate.tool);
if (annotate.session == NULL)
return -1;
symbol_conf.priv_size = sizeof(struct annotation);
symbol_conf.try_vmlinux_path = true;
ret = symbol__init(&annotate.session->header.env);
if (ret < 0)
goto out_delete;
if (setup_sorting() < 0)
usage_with_options(annotate_usage, options);
if (argc) {
/*
* Special case: if there's an argument left then assume that
* it's a symbol filter:
*/
if (argc > 1)
usage_with_options(annotate_usage, options);
annotate.sym_hist_filter = argv[0];
}
ret = __cmd_annotate(&annotate);
out_delete:
/*
* Speed up the exit process, for large files this can
* take quite a while.
*
* XXX Enable this when using valgrind or if we ever
* librarize this command.
*
* Also experiment with obstacks to see how much speed
* up we'll get here.
*
* perf_session__delete(session);
*/
return ret;
}