perf session: Use evlist/evsel for managing perf.data attributes

So that we can reuse things like the id to attr lookup routine
(perf_evlist__id2evsel) that uses a hash table instead of the linear
lookup done in the older perf_header_attr routines, etc.

Also to make evsels/evlist more pervasive an API, simplyfing using the
emerging perf lib.

cc: Arun Sharma <arun@sharma-home.net>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Tom Zanussi <tzanussi@gmail.com>
LKML-Reference: <new-submission>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

8 files changed, 140 insertions, 257 deletions

diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index 190c64c6e266..d852cefa20de 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 078d51256085..8b1cb7a4c5f1 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 8083d5126fca..662596afd7f1 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 281b60e5fc7b..6710ab538342 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 108b0db7bbef..40b10e4d3927 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -9,6 +9,7 @@
 #include <linux/kernel.h>
 
 #include "evlist.h"
+#include "evsel.h"
 #include "util.h"
 #include "header.h"
 #include "../perf.h"
@@ -19,89 +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;
 
@@ -515,33 +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  = {
@@ -580,7 +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,
@@ -861,7 +787,7 @@ static int perf_header__read_pipe(struct perf_session *session, int fd)
         return 0;
 }
 
-int perf_header__read(struct perf_session *session, int fd)
+int perf_session__read_header(struct perf_session *session, int fd)
 {
         struct perf_header *self = &session->header;
         struct perf_file_header f_header;
@@ -869,6 +795,10 @@ int perf_header__read(struct perf_session *session, int fd)
         u64                     f_id;
         int nr_attrs, nr_ids, i, j;
 
+        session->evlist = perf_evlist__new(NULL, NULL);
+        if (session->evlist == NULL)
+                return -ENOMEM;
+
         if (session->fd_pipe)
                 return perf_header__read_pipe(session, fd);
 
@@ -881,33 +811,39 @@ int perf_header__read(struct perf_session *session, int fd)
         lseek(fd, f_header.attrs.offset, SEEK_SET);
 
         for (i = 0; i < nr_attrs; i++) {
-                struct perf_header_attr *attr;
+                struct perf_evsel *evsel;
                 off_t tmp;
 
                 if (perf_header__getbuffer64(self, fd, &f_attr, sizeof(f_attr)))
                         goto out_errno;
 
                 tmp = lseek(fd, 0, SEEK_CUR);
+                evsel = perf_evsel__new(&f_attr.attr, i);
 
-                attr = perf_header_attr__new(&f_attr.attr);
-                if (attr == NULL)
-                         return -ENOMEM;
+                if (evsel == NULL)
+                        goto out_delete_evlist;
+                /*
+                 * Do it before so that if perf_evsel__alloc_id fails, this
+                 * entry gets purged too at perf_evlist__delete().
+                 */
+                perf_evlist__add(session->evlist, evsel);
 
                 nr_ids = f_attr.ids.size / 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, nr_ids))
+                        goto out_delete_evlist;
+
                 lseek(fd, f_attr.ids.offset, SEEK_SET);
 
                 for (j = 0; j < nr_ids; j++) {
                         if (perf_header__getbuffer64(self, fd, &f_id, sizeof(f_id)))
                                 goto out_errno;
 
-                        if (perf_header_attr__add_id(attr, f_id) < 0) {
-                                perf_header_attr__delete(attr);
-                                return -ENOMEM;
-                        }
-                }
-                if (perf_header__add_attr(self, attr) < 0) {
-                        perf_header_attr__delete(attr);
-                        return -ENOMEM;
+                        perf_evlist__id_add(session->evlist, evsel, 0, j, f_id);
                 }
 
                 lseek(fd, tmp, SEEK_SET);
@@ -932,37 +868,38 @@ int perf_header__read(struct perf_session *session, int fd)
         return 0;
 out_errno:
         return -errno;
+
+out_delete_evlist:
+        perf_evlist__delete(session->evlist);
+        session->evlist = NULL;
+        return -ENOMEM;
 }
 
-u64 perf_header__sample_type(struct perf_header *header)
+u64 perf_evlist__sample_type(struct perf_evlist *evlist)
 {
+        struct perf_evsel *pos;
         u64 type = 0;
-        int i;
-
-        for (i = 0; i < header->attrs; i++) {
-                struct perf_header_attr *attr = header->attr[i];
 
+        list_for_each_entry(pos, &evlist->entries, node) {
                 if (!type)
-                        type = attr->attr.sample_type;
-                else if (type != attr->attr.sample_type)
+                        type = pos->attr.sample_type;
+                else if (type != pos->attr.sample_type)
                         die("non matching sample_type");
         }
 
         return type;
 }
 
-bool perf_header__sample_id_all(const struct perf_header *header)
+bool perf_evlist__sample_id_all(const struct perf_evlist *evlist)
 {
         bool value = false, first = true;
-        int i;
-
-        for (i = 0; i < header->attrs; i++) {
-                struct perf_header_attr *attr = header->attr[i];
+        struct perf_evsel *pos;
 
+        list_for_each_entry(pos, &evlist->entries, node) {
                 if (first) {
-                        value = attr->attr.sample_id_all;
+                        value = pos->attr.sample_id_all;
                         first = false;
-                } else if (value != attr->attr.sample_id_all)
+                } else if (value != pos->attr.sample_id_all)
                         die("non matching sample_id_all");
         }
 
@@ -1000,16 +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) {
@@ -1024,27 +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 2fab13348aab..4cc267559bb6 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;
@@ -62,29 +53,19 @@ 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_header__read(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__read_header(struct perf_session *session, int fd);
+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_header__sample_type(struct perf_header *header);
-bool perf_header__sample_id_all(const struct perf_header *header);
+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);
 void perf_header__clear_feat(struct perf_header *self, int feat);
 bool perf_header__has_feat(const 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 0d414199889d..f26639fa0fb3 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -13,46 +13,6 @@
 #include "sort.h"
 #include "util.h"
 
-static int perf_session__read_evlist(struct perf_session *session)
-{
-        int i, j;
-
-        session->evlist = perf_evlist__new(NULL, NULL);
-        if (session->evlist == NULL)
-                return -ENOMEM;
-
-        for (i = 0; i < session->header.attrs; ++i) {
-                struct perf_header_attr *hattr = session->header.attr[i];
-                struct perf_evsel *evsel = perf_evsel__new(&hattr->attr, i);
-
-                if (evsel == NULL)
-                        goto out_delete_evlist;
-                /*
-                 * Do it before so that if perf_evsel__alloc_id fails, this
-                 * entry gets purged too at perf_evlist__delete().
-                 */
-                perf_evlist__add(session->evlist, evsel);
-                /*
-                 * 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, hattr->ids))
-                        goto out_delete_evlist;
-
-                for (j = 0; j < hattr->ids; ++j)
-                        perf_evlist__id_hash(session->evlist, evsel, 0, j,
-                                             hattr->id[j]);
-        }
-
-        return 0;
-
-out_delete_evlist:
-        perf_evlist__delete(session->evlist);
-        session->evlist = NULL;
-        return -ENOMEM;
-}
-
 static int perf_session__open(struct perf_session *self, bool force)
 {
         struct stat input_stat;
@@ -61,7 +21,7 @@ static int perf_session__open(struct perf_session *self, bool force)
                 self->fd_pipe = true;
                 self->fd = STDIN_FILENO;
 
-                if (perf_header__read(self, self->fd) < 0)
+                if (perf_session__read_header(self, self->fd) < 0)
                         pr_err("incompatible file format");
 
                 return 0;
@@ -93,16 +53,11 @@ static int perf_session__open(struct perf_session *self, bool force)
                 goto out_close;
         }
 
-        if (perf_header__read(self, self->fd) < 0) {
+        if (perf_session__read_header(self, self->fd) < 0) {
                 pr_err("incompatible file format");
                 goto out_close;
         }
 
-        if (perf_session__read_evlist(self) < 0) {
-                pr_err("Not enough memory to read the event selector list\n");
-                goto out_close;
-        }
-
         self->size = input_stat.st_size;
         return 0;
 
@@ -139,21 +94,10 @@ out:
        session->id_hdr_size = size;
 }
 
-void perf_session__set_sample_id_all(struct perf_session *session, bool value)
-{
-        session->sample_id_all = value;
-        perf_session__id_header_size(session);
-}
-
-void perf_session__set_sample_type(struct perf_session *session, u64 type)
-{
-        session->sample_type = type;
-}
-
 void perf_session__update_sample_type(struct perf_session *self)
 {
-        self->sample_type = perf_header__sample_type(&self->header);
-        self->sample_id_all = perf_header__sample_id_all(&self->header);
+        self->sample_type = perf_evlist__sample_type(self->evlist);
+        self->sample_id_all = perf_evlist__sample_id_all(self->evlist);
         perf_session__id_header_size(self);
 }
 
@@ -182,9 +126,6 @@ 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);
@@ -208,6 +149,7 @@ 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
@@ -217,8 +159,6 @@ 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");
@@ -227,9 +167,6 @@ 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;
@@ -260,7 +197,6 @@ 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);
diff --git a/tools/perf/util/session.h b/tools/perf/util/session.h
index 05dd7bcb9453..b5b148b0aaca 100644
--- a/tools/perf/util/session.h
+++ b/tools/perf/util/session.h
@@ -112,8 +112,6 @@ void mem_bswap_64(void *src, int byte_size);
 int perf_session__create_kernel_maps(struct perf_session *self);
 
 void perf_session__update_sample_type(struct perf_session *self);
-void perf_session__set_sample_id_all(struct perf_session *session, bool value);
-void perf_session__set_sample_type(struct perf_session *session, u64 type);
 void perf_session__remove_thread(struct perf_session *self, struct thread *th);
 
 static inline