[PATCH 02/10] perf evsel: Assume rest of perf_header_attr functions

From: Arnaldo Carvalho de Melo
Date: Wed Mar 09 2011 - 13:33:35 EST

From: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>

The append code in record can be made smarter, i.e. allowing merging of
different sets of events, but that is left for the future.

Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Cc: Stephane Eranian <eranian@xxxxxxxxxx>
Cc: Tom Zanussi <tzanussi@xxxxxxxxx>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
---
tools/perf/builtin-record.c | 92 +++++++++----------------
tools/perf/util/evlist.c | 26 +++++---
tools/perf/util/evlist.h | 4 +-
tools/perf/util/evsel.c | 21 +++++-
tools/perf/util/evsel.h | 9 ++-
tools/perf/util/header.c | 161 ++++++++++++------------------------------
tools/perf/util/header.h | 30 ++-------
tools/perf/util/session.c | 10 +---
8 files changed, 128 insertions(+), 225 deletions(-)

diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 9d236e8..81dbe27 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -31,7 +31,6 @@
#include <sys/mman.h>

#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
-#define SID(e, x, y) xyarray__entry(e->id, x, y)

enum write_mode_t {
WRITE_FORCE,
@@ -160,54 +159,6 @@ static void sig_atexit(void)
kill(getpid(), signr);
}

-static struct perf_header_attr *get_header_attr(struct perf_event_attr *a, int nr)
-{
- struct perf_header_attr *h_attr;
-
- if (nr < session->header.attrs) {
- h_attr = session->header.attr[nr];
- } else {
- h_attr = perf_header_attr__new(a);
- if (h_attr != NULL)
- if (perf_header__add_attr(&session->header, h_attr) < 0) {
- perf_header_attr__delete(h_attr);
- h_attr = NULL;
- }
- }
-
- return h_attr;
-}
-
-static void create_counter(struct perf_evsel *evsel, int cpu)
-{
- struct perf_event_attr *attr = &evsel->attr;
- struct perf_header_attr *h_attr;
- struct perf_sample_id *sid;
- int thread_index;
-
- for (thread_index = 0; thread_index < evsel_list->threads->nr; thread_index++) {
- h_attr = get_header_attr(attr, evsel->idx);
- if (h_attr == NULL)
- die("nomem\n");
-
- if (!file_new) {
- if (memcmp(&h_attr->attr, attr, sizeof(*attr))) {
- fprintf(stderr, "incompatible append\n");
- exit(-1);
- }
- }
-
- sid = SID(evsel, cpu, thread_index);
- if (perf_header_attr__add_id(h_attr, sid->id) < 0) {
- pr_warning("Not enough memory to add id\n");
- exit(-1);
- }
- }
-
- if (!sample_type)
- sample_type = attr->sample_type;
-}
-
static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
{
struct perf_event_attr *attr = &evsel->attr;
@@ -278,10 +229,28 @@ static void config_attr(struct perf_evsel *evsel, struct perf_evlist *evlist)
}
}

+static bool perf_evlist__equal(struct perf_evlist *evlist,
+ struct perf_evlist *other)
+{
+ struct perf_evsel *pos, *pair;
+
+ if (evlist->nr_entries != other->nr_entries)
+ return false;
+
+ pair = list_entry(other->entries.next, struct perf_evsel, node);
+
+ list_for_each_entry(pos, &evlist->entries, node) {
+ if (memcmp(&pos->attr, &pair->attr, sizeof(pos->attr) != 0))
+ return false;
+ pair = list_entry(pair->node.next, struct perf_evsel, node);
+ }
+
+ return true;
+}
+
static void open_counters(struct perf_evlist *evlist)
{
struct perf_evsel *pos;
- int cpu;

list_for_each_entry(pos, &evlist->entries, node) {
struct perf_event_attr *attr = &pos->attr;
@@ -364,10 +333,16 @@ try_again:
if (perf_evlist__mmap(evlist, mmap_pages, false) < 0)
die("failed to mmap with %d (%s)\n", errno, strerror(errno));

- for (cpu = 0; cpu < evsel_list->cpus->nr; ++cpu) {
- list_for_each_entry(pos, &evlist->entries, node)
- create_counter(pos, cpu);
+ if (file_new)
+ session->evlist = evlist;
+ else {
+ if (!perf_evlist__equal(session->evlist, evlist)) {
+ fprintf(stderr, "incompatible append\n");
+ exit(-1);
+ }
}
+
+ sample_type = pos->attr.sample_type;
}

static int process_buildids(void)
@@ -390,7 +365,7 @@ static void atexit_header(void)

if (!no_buildid)
process_buildids();
- perf_header__write(&session->header, evsel_list, output, true);
+ perf_session__write_header(session, evsel_list, output, true);
perf_session__delete(session);
perf_evlist__delete(evsel_list);
symbol__exit();
@@ -600,8 +575,8 @@ static int __cmd_record(int argc, const char **argv)
if (err < 0)
return err;
} else if (file_new) {
- err = perf_header__write(&session->header, evsel_list,
- output, false);
+ err = perf_session__write_header(session, evsel_list,
+ output, false);
if (err < 0)
return err;
}
@@ -611,9 +586,8 @@ static int __cmd_record(int argc, const char **argv)
perf_session__set_sample_id_all(session, sample_id_all_avail);

if (pipe_output) {
- err = perf_event__synthesize_attrs(&session->header,
- process_synthesized_event,
- session);
+ err = perf_session__synthesize_attrs(session,
+ process_synthesized_event);
if (err < 0) {
pr_err("Couldn't synthesize attrs.\n");
return err;
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 190c64c..d852cef 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -19,7 +19,7 @@
#include <linux/hash.h>

#define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
-#define SID(e, x, y) xyarray__entry(e->id, x, y)
+#define SID(e, x, y) xyarray__entry(e->sample_id, x, y)

void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
struct thread_map *threads)
@@ -106,8 +106,9 @@ void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd)
evlist->nr_fds++;
}

-void perf_evlist__id_hash(struct perf_evlist *evlist, struct perf_evsel *evsel,
- int cpu, int thread, u64 id)
+static void perf_evlist__id_hash(struct perf_evlist *evlist,
+ struct perf_evsel *evsel,
+ int cpu, int thread, u64 id)
{
int hash;
struct perf_sample_id *sid = SID(evsel, cpu, thread);
@@ -118,9 +119,16 @@ void perf_evlist__id_hash(struct perf_evlist *evlist, struct perf_evsel *evsel,
hlist_add_head(&sid->node, &evlist->heads[hash]);
}

-static int perf_evlist__id_hash_fd(struct perf_evlist *evlist,
- struct perf_evsel *evsel,
- int cpu, int thread, int fd)
+void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
+ int cpu, int thread, u64 id)
+{
+ perf_evlist__id_hash(evlist, evsel, cpu, thread, id);
+ evsel->id[evsel->ids++] = id;
+}
+
+static int perf_evlist__id_add_fd(struct perf_evlist *evlist,
+ struct perf_evsel *evsel,
+ int cpu, int thread, int fd)
{
u64 read_data[4] = { 0, };
int id_idx = 1; /* The first entry is the counter value */
@@ -134,7 +142,7 @@ static int perf_evlist__id_hash_fd(struct perf_evlist *evlist,
if (evsel->attr.read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
++id_idx;

- perf_evlist__id_hash(evlist, evsel, cpu, thread, read_data[id_idx]);
+ perf_evlist__id_add(evlist, evsel, cpu, thread, read_data[id_idx]);
return 0;
}

@@ -292,7 +300,7 @@ int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)

list_for_each_entry(evsel, &evlist->entries, node) {
if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
- evsel->id == NULL &&
+ evsel->sample_id == NULL &&
perf_evsel__alloc_id(evsel, cpus->nr, threads->nr) < 0)
return -ENOMEM;

@@ -308,7 +316,7 @@ int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite)
goto out_unmap;

if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
- perf_evlist__id_hash_fd(evlist, evsel, cpu, thread, fd) < 0)
+ perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0)
goto out_unmap;
}
}
diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h
index 078d512..8b1cb7a 100644
--- a/tools/perf/util/evlist.h
+++ b/tools/perf/util/evlist.h
@@ -38,8 +38,8 @@ void perf_evlist__delete(struct perf_evlist *evlist);
void perf_evlist__add(struct perf_evlist *evlist, struct perf_evsel *entry);
int perf_evlist__add_default(struct perf_evlist *evlist);

-void perf_evlist__id_hash(struct perf_evlist *evlist, struct perf_evsel *evsel,
- int cpu, int thread, u64 id);
+void perf_evlist__id_add(struct perf_evlist *evlist, struct perf_evsel *evsel,
+ int cpu, int thread, u64 id);

int perf_evlist__alloc_pollfd(struct perf_evlist *evlist);
void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd);
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 8083d51..662596a 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -41,8 +41,18 @@ int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)

int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
{
- evsel->id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
- return evsel->id != NULL ? 0 : -ENOMEM;
+ evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
+ if (evsel->sample_id == NULL)
+ return -ENOMEM;
+
+ evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
+ if (evsel->id == NULL) {
+ xyarray__delete(evsel->sample_id);
+ evsel->sample_id = NULL;
+ return -ENOMEM;
+ }
+
+ return 0;
}

int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
@@ -60,7 +70,9 @@ void perf_evsel__free_fd(struct perf_evsel *evsel)

void perf_evsel__free_id(struct perf_evsel *evsel)
{
- xyarray__delete(evsel->id);
+ xyarray__delete(evsel->sample_id);
+ evsel->sample_id = NULL;
+ free(evsel->id);
evsel->id = NULL;
}

@@ -79,7 +91,8 @@ void perf_evsel__exit(struct perf_evsel *evsel)
{
assert(list_empty(&evsel->node));
xyarray__delete(evsel->fd);
- xyarray__delete(evsel->id);
+ xyarray__delete(evsel->sample_id);
+ free(evsel->id);
}

void perf_evsel__delete(struct perf_evsel *evsel)
diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h
index 281b60e..6710ab5 100644
--- a/tools/perf/util/evsel.h
+++ b/tools/perf/util/evsel.h
@@ -49,12 +49,17 @@ struct perf_evsel {
struct perf_event_attr attr;
char *filter;
struct xyarray *fd;
- struct xyarray *id;
+ struct xyarray *sample_id;
+ u64 *id;
struct perf_counts *counts;
int idx;
+ int ids;
struct hists hists;
char *name;
- void *priv;
+ union {
+ void *priv;
+ off_t id_offset;
+ };
struct cgroup_sel *cgrp;
};

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 3457ec6..40b10e4 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -20,89 +20,6 @@

static bool no_buildid_cache = false;

-/*
- * Create new perf.data header attribute:
- */
-struct perf_header_attr *perf_header_attr__new(struct perf_event_attr *attr)
-{
- struct perf_header_attr *self = malloc(sizeof(*self));
-
- if (self != NULL) {
- self->attr = *attr;
- self->ids = 0;
- self->size = 1;
- self->id = malloc(sizeof(u64));
- if (self->id == NULL) {
- free(self);
- self = NULL;
- }
- }
-
- return self;
-}
-
-void perf_header_attr__delete(struct perf_header_attr *self)
-{
- free(self->id);
- free(self);
-}
-
-int perf_header_attr__add_id(struct perf_header_attr *self, u64 id)
-{
- int pos = self->ids;
-
- self->ids++;
- if (self->ids > self->size) {
- int nsize = self->size * 2;
- u64 *nid = realloc(self->id, nsize * sizeof(u64));
-
- if (nid == NULL)
- return -1;
-
- self->size = nsize;
- self->id = nid;
- }
- self->id[pos] = id;
- return 0;
-}
-
-int perf_header__init(struct perf_header *self)
-{
- self->size = 1;
- self->attr = malloc(sizeof(void *));
- return self->attr == NULL ? -ENOMEM : 0;
-}
-
-void perf_header__exit(struct perf_header *self)
-{
- int i;
- for (i = 0; i < self->attrs; ++i)
- perf_header_attr__delete(self->attr[i]);
- free(self->attr);
-}
-
-int perf_header__add_attr(struct perf_header *self,
- struct perf_header_attr *attr)
-{
- if (self->frozen)
- return -1;
-
- if (self->attrs == self->size) {
- int nsize = self->size * 2;
- struct perf_header_attr **nattr;
-
- nattr = realloc(self->attr, nsize * sizeof(void *));
- if (nattr == NULL)
- return -1;
-
- self->size = nsize;
- self->attr = nattr;
- }
-
- self->attr[self->attrs++] = attr;
- return 0;
-}
-
static int event_count;
static struct perf_trace_event_type *events;

@@ -516,33 +433,41 @@ int perf_header__write_pipe(int fd)
return 0;
}

-int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
- int fd, bool at_exit)
+int perf_session__write_header(struct perf_session *session,
+ struct perf_evlist *evlist,
+ int fd, bool at_exit)
{
struct perf_file_header f_header;
struct perf_file_attr f_attr;
- struct perf_header_attr *attr;
- int i, err;
+ struct perf_header *self = &session->header;
+ struct perf_evsel *attr, *pair = NULL;
+ int err;

lseek(fd, sizeof(f_header), SEEK_SET);

- for (i = 0; i < self->attrs; i++) {
- attr = self->attr[i];
+ if (session->evlist != evlist)
+ pair = list_entry(session->evlist->entries.next, struct perf_evsel, node);

+ list_for_each_entry(attr, &evlist->entries, node) {
attr->id_offset = lseek(fd, 0, SEEK_CUR);
err = do_write(fd, attr->id, attr->ids * sizeof(u64));
if (err < 0) {
+out_err_write:
pr_debug("failed to write perf header\n");
return err;
}
+ if (session->evlist != evlist) {
+ err = do_write(fd, pair->id, pair->ids * sizeof(u64));
+ if (err < 0)
+ goto out_err_write;
+ attr->ids += pair->ids;
+ pair = list_entry(pair->node.next, struct perf_evsel, node);
+ }
}

-
self->attr_offset = lseek(fd, 0, SEEK_CUR);

- for (i = 0; i < self->attrs; i++) {
- attr = self->attr[i];
-
+ list_for_each_entry(attr, &evlist->entries, node) {
f_attr = (struct perf_file_attr){
.attr = attr->attr,
.ids = {
@@ -581,7 +506,7 @@ int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
.attr_size = sizeof(f_attr),
.attrs = {
.offset = self->attr_offset,
- .size = self->attrs * sizeof(f_attr),
+ .size = evlist->nr_entries * sizeof(f_attr),
},
.data = {
.offset = self->data_offset,
@@ -918,7 +843,7 @@ int perf_session__read_header(struct perf_session *session, int fd)
if (perf_header__getbuffer64(self, fd, &f_id, sizeof(f_id)))
goto out_errno;

- perf_evlist__id_hash(session->evlist, evsel, 0, j, f_id);
+ perf_evlist__id_add(session->evlist, evsel, 0, j, f_id);
}

lseek(fd, tmp, SEEK_SET);
@@ -1012,16 +937,13 @@ int perf_event__synthesize_attr(struct perf_event_attr *attr, u16 ids, u64 *id,
return err;
}

-int perf_event__synthesize_attrs(struct perf_header *self,
- perf_event__handler_t process,
- struct perf_session *session)
+int perf_session__synthesize_attrs(struct perf_session *session,
+ perf_event__handler_t process)
{
- struct perf_header_attr *attr;
- int i, err = 0;
-
- for (i = 0; i < self->attrs; i++) {
- attr = self->attr[i];
+ struct perf_evsel *attr;
+ int err = 0;

+ list_for_each_entry(attr, &session->evlist->entries, node) {
err = perf_event__synthesize_attr(&attr->attr, attr->ids,
attr->id, process, session);
if (err) {
@@ -1036,27 +958,36 @@ int perf_event__synthesize_attrs(struct perf_header *self,
int perf_event__process_attr(union perf_event *event,
struct perf_session *session)
{
- struct perf_header_attr *attr;
unsigned int i, ids, n_ids;
+ struct perf_evsel *evsel;

- attr = perf_header_attr__new(&event->attr.attr);
- if (attr == NULL)
+ if (session->evlist == NULL) {
+ session->evlist = perf_evlist__new(NULL, NULL);
+ if (session->evlist == NULL)
+ return -ENOMEM;
+ }
+
+ evsel = perf_evsel__new(&event->attr.attr,
+ session->evlist->nr_entries);
+ if (evsel == NULL)
return -ENOMEM;

+ perf_evlist__add(session->evlist, evsel);
+
ids = event->header.size;
ids -= (void *)&event->attr.id - (void *)event;
n_ids = ids / sizeof(u64);
+ /*
+ * We don't have the cpu and thread maps on the header, so
+ * for allocating the perf_sample_id table we fake 1 cpu and
+ * hattr->ids threads.
+ */
+ if (perf_evsel__alloc_id(evsel, 1, n_ids))
+ return -ENOMEM;

for (i = 0; i < n_ids; i++) {
- if (perf_header_attr__add_id(attr, event->attr.id[i]) < 0) {
- perf_header_attr__delete(attr);
- return -ENOMEM;
- }
- }
-
- if (perf_header__add_attr(&session->header, attr) < 0) {
- perf_header_attr__delete(attr);
- return -ENOMEM;
+ perf_evlist__id_add(session->evlist, evsel, 0, i,
+ event->attr.id[i]);
}

perf_session__update_sample_type(session);
diff --git a/tools/perf/util/header.h b/tools/perf/util/header.h
index 73b84eb..4cc2675 100644
--- a/tools/perf/util/header.h
+++ b/tools/perf/util/header.h
@@ -9,13 +9,6 @@

#include <linux/bitmap.h>

-struct perf_header_attr {
- struct perf_event_attr attr;
- int ids, size;
- u64 *id;
- off_t id_offset;
-};
-
enum {
HEADER_TRACE_INFO = 1,
HEADER_BUILD_ID,
@@ -51,9 +44,7 @@ int perf_file_header__read(struct perf_file_header *self,

struct perf_header {
int frozen;
- int attrs, size;
bool needs_swap;
- struct perf_header_attr **attr;
s64 attr_offset;
u64 data_offset;
u64 data_size;
@@ -62,27 +53,17 @@ struct perf_header {
DECLARE_BITMAP(adds_features, HEADER_FEAT_BITS);
};

-int perf_header__init(struct perf_header *self);
-void perf_header__exit(struct perf_header *self);
-
struct perf_evlist;

int perf_session__read_header(struct perf_session *session, int fd);
-int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
- int fd, bool at_exit);
+int perf_session__write_header(struct perf_session *session,
+ struct perf_evlist *evlist,
+ int fd, bool at_exit);
int perf_header__write_pipe(int fd);

-int perf_header__add_attr(struct perf_header *self,
- struct perf_header_attr *attr);
-
int perf_header__push_event(u64 id, const char *name);
char *perf_header__find_event(u64 id);

-struct perf_header_attr *perf_header_attr__new(struct perf_event_attr *attr);
-void perf_header_attr__delete(struct perf_header_attr *self);
-
-int perf_header_attr__add_id(struct perf_header_attr *self, u64 id);
-
u64 perf_evlist__sample_type(struct perf_evlist *evlist);
bool perf_evlist__sample_id_all(const struct perf_evlist *evlist);
void perf_header__set_feat(struct perf_header *self, int feat);
@@ -101,9 +82,8 @@ int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir);
int perf_event__synthesize_attr(struct perf_event_attr *attr, u16 ids, u64 *id,
perf_event__handler_t process,
struct perf_session *session);
-int perf_event__synthesize_attrs(struct perf_header *self,
- perf_event__handler_t process,
- struct perf_session *session);
+int perf_session__synthesize_attrs(struct perf_session *session,
+ perf_event__handler_t process);
int perf_event__process_attr(union perf_event *event, struct perf_session *session);

int perf_event__synthesize_event_type(u64 event_id, char *name,
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 26b24c5..f642615 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -137,9 +137,6 @@ struct perf_session *perf_session__new(const char *filename, int mode,
if (self == NULL)
goto out;

- if (perf_header__init(&self->header) < 0)
- goto out_free;
-
memcpy(self->filename, filename, len);
self->threads = RB_ROOT;
INIT_LIST_HEAD(&self->dead_threads);
@@ -163,6 +160,7 @@ struct perf_session *perf_session__new(const char *filename, int mode,
if (mode == O_RDONLY) {
if (perf_session__open(self, force) < 0)
goto out_delete;
+ perf_session__update_sample_type(self);
} else if (mode == O_WRONLY) {
/*
* In O_RDONLY mode this will be performed when reading the
@@ -172,8 +170,6 @@ struct perf_session *perf_session__new(const char *filename, int mode,
goto out_delete;
}

- perf_session__update_sample_type(self);
-
if (ops && ops->ordering_requires_timestamps &&
ops->ordered_samples && !self->sample_id_all) {
dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
@@ -182,9 +178,6 @@ struct perf_session *perf_session__new(const char *filename, int mode,

out:
return self;
-out_free:
- free(self);
- return NULL;
out_delete:
perf_session__delete(self);
return NULL;
@@ -215,7 +208,6 @@ static void perf_session__delete_threads(struct perf_session *self)

void perf_session__delete(struct perf_session *self)
{
- perf_header__exit(&self->header);
perf_session__destroy_kernel_maps(self);
perf_session__delete_dead_threads(self);
perf_session__delete_threads(self);
--
1.6.2.5

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