Merge branch 'perf/core' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux-2.6 into perf/core

9 files changed, 278 insertions, 376 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..5a72d421e211 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;
 
@@ -148,19 +66,19 @@ struct perf_file_attr {
 	struct perf_file_section	ids;
 };
 
-void perf_header__set_feat(struct perf_header *self, int feat)
+void perf_header__set_feat(struct perf_header *header, int feat)
 {
-	set_bit(feat, self->adds_features);
+	set_bit(feat, header->adds_features);
 }
 
-void perf_header__clear_feat(struct perf_header *self, int feat)
+void perf_header__clear_feat(struct perf_header *header, int feat)
 {
-	clear_bit(feat, self->adds_features);
+	clear_bit(feat, header->adds_features);
 }
 
-bool perf_header__has_feat(const struct perf_header *self, int feat)
+bool perf_header__has_feat(const struct perf_header *header, int feat)
 {
-	return test_bit(feat, self->adds_features);
+	return test_bit(feat, header->adds_features);
 }
 
 static int do_write(int fd, const void *buf, size_t size)
@@ -229,22 +147,22 @@ static int __dsos__write_buildid_table(struct list_head *head, pid_t pid,
 	return 0;
 }
 
-static int machine__write_buildid_table(struct machine *self, int fd)
+static int machine__write_buildid_table(struct machine *machine, int fd)
 {
 	int err;
 	u16 kmisc = PERF_RECORD_MISC_KERNEL,
 	    umisc = PERF_RECORD_MISC_USER;
 
-	if (!machine__is_host(self)) {
+	if (!machine__is_host(machine)) {
 		kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
 		umisc = PERF_RECORD_MISC_GUEST_USER;
 	}
 
-	err = __dsos__write_buildid_table(&self->kernel_dsos, self->pid,
+	err = __dsos__write_buildid_table(&machine->kernel_dsos, machine->pid,
 					  kmisc, fd);
 	if (err == 0)
-		err = __dsos__write_buildid_table(&self->user_dsos,
-						  self->pid, umisc, fd);
+		err = __dsos__write_buildid_table(&machine->user_dsos,
+						  machine->pid, umisc, fd);
 	return err;
 }
 
@@ -362,12 +280,12 @@ out_free:
 	return err;
 }
 
-static int dso__cache_build_id(struct dso *self, const char *debugdir)
+static int dso__cache_build_id(struct dso *dso, const char *debugdir)
 {
-	bool is_kallsyms = self->kernel && self->long_name[0] != '/';
+	bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
 
-	return build_id_cache__add_b(self->build_id, sizeof(self->build_id),
-				     self->long_name, debugdir, is_kallsyms);
+	return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id),
+				     dso->long_name, debugdir, is_kallsyms);
 }
 
 static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
@@ -382,14 +300,14 @@ static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
 	return err;
 }
 
-static int machine__cache_build_ids(struct machine *self, const char *debugdir)
+static int machine__cache_build_ids(struct machine *machine, const char *debugdir)
 {
-	int ret = __dsos__cache_build_ids(&self->kernel_dsos, debugdir);
-	ret |= __dsos__cache_build_ids(&self->user_dsos, debugdir);
+	int ret = __dsos__cache_build_ids(&machine->kernel_dsos, debugdir);
+	ret |= __dsos__cache_build_ids(&machine->user_dsos, debugdir);
 	return ret;
 }
 
-static int perf_session__cache_build_ids(struct perf_session *self)
+static int perf_session__cache_build_ids(struct perf_session *session)
 {
 	struct rb_node *nd;
 	int ret;
@@ -400,28 +318,28 @@ static int perf_session__cache_build_ids(struct perf_session *self)
 	if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
 		return -1;
 
-	ret = machine__cache_build_ids(&self->host_machine, debugdir);
+	ret = machine__cache_build_ids(&session->host_machine, debugdir);
 
-	for (nd = rb_first(&self->machines); nd; nd = rb_next(nd)) {
+	for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
 		struct machine *pos = rb_entry(nd, struct machine, rb_node);
 		ret |= machine__cache_build_ids(pos, debugdir);
 	}
 	return ret ? -1 : 0;
 }
 
-static bool machine__read_build_ids(struct machine *self, bool with_hits)
+static bool machine__read_build_ids(struct machine *machine, bool with_hits)
 {
-	bool ret = __dsos__read_build_ids(&self->kernel_dsos, with_hits);
-	ret |= __dsos__read_build_ids(&self->user_dsos, with_hits);
+	bool ret = __dsos__read_build_ids(&machine->kernel_dsos, with_hits);
+	ret |= __dsos__read_build_ids(&machine->user_dsos, with_hits);
 	return ret;
 }
 
-static bool perf_session__read_build_ids(struct perf_session *self, bool with_hits)
+static bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
 {
 	struct rb_node *nd;
-	bool ret = machine__read_build_ids(&self->host_machine, with_hits);
+	bool ret = machine__read_build_ids(&session->host_machine, with_hits);
 
-	for (nd = rb_first(&self->machines); nd; nd = rb_next(nd)) {
+	for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
 		struct machine *pos = rb_entry(nd, struct machine, rb_node);
 		ret |= machine__read_build_ids(pos, with_hits);
 	}
@@ -429,7 +347,7 @@ static bool perf_session__read_build_ids(struct perf_session *self, bool with_hi
 	return ret;
 }
 
-static int perf_header__adds_write(struct perf_header *self,
+static int perf_header__adds_write(struct perf_header *header,
 				   struct perf_evlist *evlist, int fd)
 {
 	int nr_sections;
@@ -439,13 +357,13 @@ static int perf_header__adds_write(struct perf_header *self,
 	u64 sec_start;
 	int idx = 0, err;
 
-	session = container_of(self, struct perf_session, header);
+	session = container_of(header, struct perf_session, header);
 
-	if (perf_header__has_feat(self, HEADER_BUILD_ID &&
+	if (perf_header__has_feat(header, HEADER_BUILD_ID &&
 	    !perf_session__read_build_ids(session, true)))
-		perf_header__clear_feat(self, HEADER_BUILD_ID);
+		perf_header__clear_feat(header, HEADER_BUILD_ID);
 
-	nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
+	nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
 	if (!nr_sections)
 		return 0;
 
@@ -455,10 +373,10 @@ static int perf_header__adds_write(struct perf_header *self,
 
 	sec_size = sizeof(*feat_sec) * nr_sections;
 
-	sec_start = self->data_offset + self->data_size;
+	sec_start = header->data_offset + header->data_size;
 	lseek(fd, sec_start + sec_size, SEEK_SET);
 
-	if (perf_header__has_feat(self, HEADER_TRACE_INFO)) {
+	if (perf_header__has_feat(header, HEADER_TRACE_INFO)) {
 		struct perf_file_section *trace_sec;
 
 		trace_sec = &feat_sec[idx++];
@@ -469,14 +387,14 @@ static int perf_header__adds_write(struct perf_header *self,
 		trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
 	}
 
-	if (perf_header__has_feat(self, HEADER_BUILD_ID)) {
+	if (perf_header__has_feat(header, HEADER_BUILD_ID)) {
 		struct perf_file_section *buildid_sec;
 
 		buildid_sec = &feat_sec[idx++];
 
 		/* Write build-ids */
 		buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
-		err = dsos__write_buildid_table(self, fd);
+		err = dsos__write_buildid_table(header, fd);
 		if (err < 0) {
 			pr_debug("failed to write buildid table\n");
 			goto out_free;
@@ -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 *header = &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);
+		}
 	}
 
+	header->attr_offset = lseek(fd, 0, SEEK_CUR);
 
-	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  = {
@@ -556,20 +482,20 @@ int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
 		}
 	}
 
-	self->event_offset = lseek(fd, 0, SEEK_CUR);
-	self->event_size = event_count * sizeof(struct perf_trace_event_type);
+	header->event_offset = lseek(fd, 0, SEEK_CUR);
+	header->event_size = event_count * sizeof(struct perf_trace_event_type);
 	if (events) {
-		err = do_write(fd, events, self->event_size);
+		err = do_write(fd, events, header->event_size);
 		if (err < 0) {
 			pr_debug("failed to write perf header events\n");
 			return err;
 		}
 	}
 
-	self->data_offset = lseek(fd, 0, SEEK_CUR);
+	header->data_offset = lseek(fd, 0, SEEK_CUR);
 
 	if (at_exit) {
-		err = perf_header__adds_write(self, evlist, fd);
+		err = perf_header__adds_write(header, evlist, fd);
 		if (err < 0)
 			return err;
 	}
@@ -579,20 +505,20 @@ int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
 		.size	   = sizeof(f_header),
 		.attr_size = sizeof(f_attr),
 		.attrs = {
-			.offset = self->attr_offset,
-			.size   = self->attrs * sizeof(f_attr),
+			.offset = header->attr_offset,
+			.size   = evlist->nr_entries * sizeof(f_attr),
 		},
 		.data = {
-			.offset = self->data_offset,
-			.size	= self->data_size,
+			.offset = header->data_offset,
+			.size	= header->data_size,
 		},
 		.event_types = {
-			.offset = self->event_offset,
-			.size	= self->event_size,
+			.offset = header->event_offset,
+			.size	= header->event_size,
 		},
 	};
 
-	memcpy(&f_header.adds_features, &self->adds_features, sizeof(self->adds_features));
+	memcpy(&f_header.adds_features, &header->adds_features, sizeof(header->adds_features));
 
 	lseek(fd, 0, SEEK_SET);
 	err = do_write(fd, &f_header, sizeof(f_header));
@@ -600,26 +526,26 @@ int perf_header__write(struct perf_header *self, struct perf_evlist *evlist,
 		pr_debug("failed to write perf header\n");
 		return err;
 	}
-	lseek(fd, self->data_offset + self->data_size, SEEK_SET);
+	lseek(fd, header->data_offset + header->data_size, SEEK_SET);
 
-	self->frozen = 1;
+	header->frozen = 1;
 	return 0;
 }
 
-static int perf_header__getbuffer64(struct perf_header *self,
+static int perf_header__getbuffer64(struct perf_header *header,
 				    int fd, void *buf, size_t size)
 {
 	if (readn(fd, buf, size) <= 0)
 		return -1;
 
-	if (self->needs_swap)
+	if (header->needs_swap)
 		mem_bswap_64(buf, size);
 
 	return 0;
 }
 
-int perf_header__process_sections(struct perf_header *self, int fd,
-				  int (*process)(struct perf_file_section *self,
+int perf_header__process_sections(struct perf_header *header, int fd,
+				  int (*process)(struct perf_file_section *section,
 						 struct perf_header *ph,
 						 int feat, int fd))
 {
@@ -629,7 +555,7 @@ int perf_header__process_sections(struct perf_header *self, int fd,
 	int idx = 0;
 	int err = -1, feat = 1;
 
-	nr_sections = bitmap_weight(self->adds_features, HEADER_FEAT_BITS);
+	nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
 	if (!nr_sections)
 		return 0;
 
@@ -639,17 +565,17 @@ int perf_header__process_sections(struct perf_header *self, int fd,
 
 	sec_size = sizeof(*feat_sec) * nr_sections;
 
-	lseek(fd, self->data_offset + self->data_size, SEEK_SET);
+	lseek(fd, header->data_offset + header->data_size, SEEK_SET);
 
-	if (perf_header__getbuffer64(self, fd, feat_sec, sec_size))
+	if (perf_header__getbuffer64(header, fd, feat_sec, sec_size))
 		goto out_free;
 
 	err = 0;
 	while (idx < nr_sections && feat < HEADER_LAST_FEATURE) {
-		if (perf_header__has_feat(self, feat)) {
+		if (perf_header__has_feat(header, feat)) {
 			struct perf_file_section *sec = &feat_sec[idx++];
 
-			err = process(sec, self, feat, fd);
+			err = process(sec, header, feat, fd);
 			if (err < 0)
 				break;
 		}
@@ -660,35 +586,35 @@ out_free:
 	return err;
 }
 
-int perf_file_header__read(struct perf_file_header *self,
+int perf_file_header__read(struct perf_file_header *header,
 			   struct perf_header *ph, int fd)
 {
 	lseek(fd, 0, SEEK_SET);
 
-	if (readn(fd, self, sizeof(*self)) <= 0 ||
-	    memcmp(&self->magic, __perf_magic, sizeof(self->magic)))
+	if (readn(fd, header, sizeof(*header)) <= 0 ||
+	    memcmp(&header->magic, __perf_magic, sizeof(header->magic)))
 		return -1;
 
-	if (self->attr_size != sizeof(struct perf_file_attr)) {
-		u64 attr_size = bswap_64(self->attr_size);
+	if (header->attr_size != sizeof(struct perf_file_attr)) {
+		u64 attr_size = bswap_64(header->attr_size);
 
 		if (attr_size != sizeof(struct perf_file_attr))
 			return -1;
 
-		mem_bswap_64(self, offsetof(struct perf_file_header,
+		mem_bswap_64(header, offsetof(struct perf_file_header,
 					    adds_features));
 		ph->needs_swap = true;
 	}
 
-	if (self->size != sizeof(*self)) {
+	if (header->size != sizeof(*header)) {
 		/* Support the previous format */
-		if (self->size == offsetof(typeof(*self), adds_features))
-			bitmap_zero(self->adds_features, HEADER_FEAT_BITS);
+		if (header->size == offsetof(typeof(*header), adds_features))
+			bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
 		else
 			return -1;
 	}
 
-	memcpy(&ph->adds_features, &self->adds_features,
+	memcpy(&ph->adds_features, &header->adds_features,
 	       sizeof(ph->adds_features));
 	/*
 	 * FIXME: hack that assumes that if we need swap the perf.data file
@@ -702,10 +628,10 @@ int perf_file_header__read(struct perf_file_header *self,
 		perf_header__set_feat(ph, HEADER_BUILD_ID);
 	}
 
-	ph->event_offset = self->event_types.offset;
-	ph->event_size   = self->event_types.size;
-	ph->data_offset  = self->data.offset;
-	ph->data_size	 = self->data.size;
+	ph->event_offset = header->event_types.offset;
+	ph->event_size   = header->event_types.size;
+	ph->data_offset  = header->data.offset;
+	ph->data_size	 = header->data.size;
 	return 0;
 }
 
@@ -764,11 +690,10 @@ out:
 	return err;
 }
 
-static int perf_header__read_build_ids(struct perf_header *self,
-			int input, u64 offset, u64 size)
+static int perf_header__read_build_ids(struct perf_header *header,
+				       int input, u64 offset, u64 size)
 {
-	struct perf_session *session = container_of(self,
-			struct perf_session, header);
+	struct perf_session *session = container_of(header, struct perf_session, header);
 	struct build_id_event bev;
 	char filename[PATH_MAX];
 	u64 limit = offset + size;
@@ -780,7 +705,7 @@ static int perf_header__read_build_ids(struct perf_header *self,
 		if (read(input, &bev, sizeof(bev)) != sizeof(bev))
 			goto out;
 
-		if (self->needs_swap)
+		if (header->needs_swap)
 			perf_event_header__bswap(&bev.header);
 
 		len = bev.header.size - sizeof(bev);
@@ -796,13 +721,13 @@ out:
 	return err;
 }
 
-static int perf_file_section__process(struct perf_file_section *self,
+static int perf_file_section__process(struct perf_file_section *section,
 				      struct perf_header *ph,
 				      int feat, int fd)
 {
-	if (lseek(fd, self->offset, SEEK_SET) == (off_t)-1) {
+	if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
 		pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
-			  "%d, continuing...\n", self->offset, feat);
+			  "%d, continuing...\n", section->offset, feat);
 		return 0;
 	}
 
@@ -812,7 +737,7 @@ static int perf_file_section__process(struct perf_file_section *self,
 		break;
 
 	case HEADER_BUILD_ID:
-		if (perf_header__read_build_ids(ph, fd, self->offset, self->size))
+		if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
 			pr_debug("Failed to read buildids, continuing...\n");
 		break;
 	default:
@@ -822,21 +747,21 @@ static int perf_file_section__process(struct perf_file_section *self,
 	return 0;
 }
 
-static int perf_file_header__read_pipe(struct perf_pipe_file_header *self,
+static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
 				       struct perf_header *ph, int fd,
 				       bool repipe)
 {
-	if (readn(fd, self, sizeof(*self)) <= 0 ||
-	    memcmp(&self->magic, __perf_magic, sizeof(self->magic)))
+	if (readn(fd, header, sizeof(*header)) <= 0 ||
+	    memcmp(&header->magic, __perf_magic, sizeof(header->magic)))
 		return -1;
 
-	if (repipe && do_write(STDOUT_FILENO, self, sizeof(*self)) < 0)
+	if (repipe && do_write(STDOUT_FILENO, header, sizeof(*header)) < 0)
 		return -1;
 
-	if (self->size != sizeof(*self)) {
-		u64 size = bswap_64(self->size);
+	if (header->size != sizeof(*header)) {
+		u64 size = bswap_64(header->size);
 
-		if (size != sizeof(*self))
+		if (size != sizeof(*header))
 			return -1;
 
 		ph->needs_swap = true;
@@ -847,10 +772,10 @@ static int perf_file_header__read_pipe(struct perf_pipe_file_header *self,
 
 static int perf_header__read_pipe(struct perf_session *session, int fd)
 {
-	struct perf_header *self = &session->header;
+	struct perf_header *header = &session->header;
 	struct perf_pipe_file_header f_header;
 
-	if (perf_file_header__read_pipe(&f_header, self, fd,
+	if (perf_file_header__read_pipe(&f_header, header, fd,
 					session->repipe) < 0) {
 		pr_debug("incompatible file format\n");
 		return -EINVAL;
@@ -861,18 +786,22 @@ 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_header *header = &session->header;
 	struct perf_file_header	f_header;
 	struct perf_file_attr	f_attr;
 	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);
 
-	if (perf_file_header__read(&f_header, self, fd) < 0) {
+	if (perf_file_header__read(&f_header, header, fd) < 0) {
 		pr_debug("incompatible file format\n");
 		return -EINVAL;
 	}
@@ -881,33 +810,39 @@ 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)))
+		if (perf_header__getbuffer64(header, 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)))
+			if (perf_header__getbuffer64(header, 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);
@@ -918,51 +853,52 @@ int perf_header__read(struct perf_session *session, int fd)
 		events = malloc(f_header.event_types.size);
 		if (events == NULL)
 			return -ENOMEM;
-		if (perf_header__getbuffer64(self, fd, events,
+		if (perf_header__getbuffer64(header, fd, events,
 					     f_header.event_types.size))
 			goto out_errno;
 		event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
 	}
 
-	perf_header__process_sections(self, fd, perf_file_section__process);
+	perf_header__process_sections(header, fd, perf_file_section__process);
 
-	lseek(fd, self->data_offset, SEEK_SET);
+	lseek(fd, header->data_offset, SEEK_SET);
 
-	self->frozen = 1;
+	header->frozen = 1;
 	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 +936,13 @@ 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 +957,36 @@ 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..456661d7f10e 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,
@@ -46,14 +39,12 @@ struct perf_pipe_file_header {
 
 struct perf_header;
 
-int perf_file_header__read(struct perf_file_header *self,
+int perf_file_header__read(struct perf_file_header *header,
 			   struct perf_header *ph, int fd);
 
 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;
@@ -62,35 +53,25 @@ 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);
+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 *header, int feat);
+void perf_header__clear_feat(struct perf_header *header, int feat);
+bool perf_header__has_feat(const struct perf_header *header, int feat);
 
-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);
-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);
-
-int perf_header__process_sections(struct perf_header *self, int fd,
-				  int (*process)(struct perf_file_section *self,
+int perf_header__process_sections(struct perf_header *header, int fd,
+				  int (*process)(struct perf_file_section *section,
 						 struct perf_header *ph,
 						 int feat, int fd));
 
@@ -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
diff --git a/tools/perf/util/top.c b/tools/perf/util/top.c
index 70a9c13f4ad5..75cfe4d45119 100644
--- a/tools/perf/util/top.c
+++ b/tools/perf/util/top.c
@@ -61,6 +61,12 @@ static void rb_insert_active_sym(struct rb_root *tree, struct sym_entry *se)
 	rb_insert_color(&se->rb_node, tree);
 }
 
+#define SNPRINTF(buf, size, fmt, args...) \
+({ \
+	size_t r = snprintf(buf, size, fmt, ## args); \
+	r > size ?  size : r; \
+})
+
 size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 {
 	struct perf_evsel *counter;
@@ -70,7 +76,7 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 	size_t ret = 0;
 
 	if (!perf_guest) {
-		ret = snprintf(bf, size,
+		ret = SNPRINTF(bf, size,
 			       "   PerfTop:%8.0f irqs/sec  kernel:%4.1f%%"
 			       "  exact: %4.1f%% [", samples_per_sec,
 			       100.0 - (100.0 * ((samples_per_sec - ksamples_per_sec) /
@@ -81,7 +87,7 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 		float guest_kernel_samples_per_sec = top->guest_kernel_samples / top->delay_secs;
 		float guest_us_samples_per_sec = top->guest_us_samples / top->delay_secs;
 
-		ret = snprintf(bf, size,
+		ret = SNPRINTF(bf, size,
 			       "   PerfTop:%8.0f irqs/sec  kernel:%4.1f%% us:%4.1f%%"
 			       " guest kernel:%4.1f%% guest us:%4.1f%%"
 			       " exact: %4.1f%% [", samples_per_sec,
@@ -101,38 +107,52 @@ size_t perf_top__header_snprintf(struct perf_top *top, char *bf, size_t size)
 	if (top->evlist->nr_entries == 1 || !top->display_weighted) {
 		struct perf_evsel *first;
 		first = list_entry(top->evlist->entries.next, struct perf_evsel, node);
-		ret += snprintf(bf + ret, size - ret, "%" PRIu64 "%s ",
+		ret += SNPRINTF(bf + ret, size - ret, "%" PRIu64 "%s ",
 				(uint64_t)first->attr.sample_period,
 				top->freq ? "Hz" : "");
 	}
 
 	if (!top->display_weighted) {
-		ret += snprintf(bf + ret, size - ret, "%s",
+		ret += SNPRINTF(bf + ret, size - ret, "%s",
 				event_name(top->sym_evsel));
-	} else list_for_each_entry(counter, &top->evlist->entries, node) {
-		ret += snprintf(bf + ret, size - ret, "%s%s",
-				counter->idx ? "/" : "", event_name(counter));
+	} else {
+		/*
+		 * Don't let events eat all the space. Leaving 30 bytes
+		 * for the rest should be enough.
+		 */
+		size_t last_pos = size - 30;
+
+		list_for_each_entry(counter, &top->evlist->entries, node) {
+			ret += SNPRINTF(bf + ret, size - ret, "%s%s",
+					counter->idx ? "/" : "",
+					event_name(counter));
+			if (ret > last_pos) {
+				sprintf(bf + last_pos - 3, "..");
+				ret = last_pos - 1;
+				break;
+			}
+		}
 	}
 
-	ret += snprintf(bf + ret, size - ret, "], ");
+	ret += SNPRINTF(bf + ret, size - ret, "], ");
 
 	if (top->target_pid != -1)
-		ret += snprintf(bf + ret, size - ret, " (target_pid: %d",
+		ret += SNPRINTF(bf + ret, size - ret, " (target_pid: %d",
 				top->target_pid);
 	else if (top->target_tid != -1)
-		ret += snprintf(bf + ret, size - ret, " (target_tid: %d",
+		ret += SNPRINTF(bf + ret, size - ret, " (target_tid: %d",
 				top->target_tid);
 	else
-		ret += snprintf(bf + ret, size - ret, " (all");
+		ret += SNPRINTF(bf + ret, size - ret, " (all");
 
 	if (top->cpu_list)
-		ret += snprintf(bf + ret, size - ret, ", CPU%s: %s)",
+		ret += SNPRINTF(bf + ret, size - ret, ", CPU%s: %s)",
 				top->evlist->cpus->nr > 1 ? "s" : "", top->cpu_list);
 	else {
 		if (top->target_tid != -1)
-			ret += snprintf(bf + ret, size - ret, ")");
+			ret += SNPRINTF(bf + ret, size - ret, ")");
 		else
-			ret += snprintf(bf + ret, size - ret, ", %d CPU%s)",
+			ret += SNPRINTF(bf + ret, size - ret, ", %d CPU%s)",
 					top->evlist->cpus->nr,
 					top->evlist->cpus->nr > 1 ? "s" : "");
 	}