Merge branch 'next' into for-linus

Prepare input updates for 5.20 (or 6.0) merge window.

18 files changed, 233 insertions, 104 deletions

diff --git a/tools/lib/perf/Documentation/libperf.txt b/tools/lib/perf/Documentation/libperf.txt
index 32c5051c24eb..a8f1a237931b 100644
--- a/tools/lib/perf/Documentation/libperf.txt
+++ b/tools/lib/perf/Documentation/libperf.txt
@@ -62,11 +62,12 @@ SYNOPSIS
   struct perf_thread_map;
 
   struct perf_thread_map *perf_thread_map__new_dummy(void);
+  struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array);
 
-  void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid);
-  char *perf_thread_map__comm(struct perf_thread_map *map, int thread);
+  void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid);
+  char *perf_thread_map__comm(struct perf_thread_map *map, int idx);
   int perf_thread_map__nr(struct perf_thread_map *threads);
-  pid_t perf_thread_map__pid(struct perf_thread_map *map, int thread);
+  pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx);
 
   struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map);
   void perf_thread_map__put(struct perf_thread_map *map);
diff --git a/tools/lib/perf/Makefile b/tools/lib/perf/Makefile
index 08fe6e3c4089..21df023a2103 100644
--- a/tools/lib/perf/Makefile
+++ b/tools/lib/perf/Makefile
@@ -153,7 +153,7 @@ $(TESTS_STATIC): $(TESTS_IN) $(LIBPERF_A) $(LIBAPI)
 	$(QUIET_LINK)$(CC) -o $@ $^
 
 $(TESTS_SHARED): $(TESTS_IN) $(LIBAPI)
-	$(QUIET_LINK)$(CC) -o $@ -L$(if $(OUTPUT),$(OUTPUT),.) $^ -lperf
+	$(QUIET_LINK)$(CC) -o $@ -L$(or $(OUTPUT),.) $^ -lperf
 
 make-tests: libs $(TESTS_SHARED) $(TESTS_STATIC)
 
diff --git a/tools/lib/perf/cpumap.c b/tools/lib/perf/cpumap.c
index ee66760f1e63..384d5e076ee4 100644
--- a/tools/lib/perf/cpumap.c
+++ b/tools/lib/perf/cpumap.c
@@ -319,6 +319,26 @@ struct perf_cpu perf_cpu_map__max(struct perf_cpu_map *map)
 	return map->nr > 0 ? map->map[map->nr - 1] : result;
 }
 
+/** Is 'b' a subset of 'a'. */
+bool perf_cpu_map__is_subset(const struct perf_cpu_map *a, const struct perf_cpu_map *b)
+{
+	if (a == b || !b)
+		return true;
+	if (!a || b->nr > a->nr)
+		return false;
+
+	for (int i = 0, j = 0; i < a->nr; i++) {
+		if (a->map[i].cpu > b->map[j].cpu)
+			return false;
+		if (a->map[i].cpu == b->map[j].cpu) {
+			j++;
+			if (j == b->nr)
+				return true;
+		}
+	}
+	return false;
+}
+
 /*
  * Merge two cpumaps
  *
@@ -335,17 +355,12 @@ struct perf_cpu_map *perf_cpu_map__merge(struct perf_cpu_map *orig,
 	int i, j, k;
 	struct perf_cpu_map *merged;
 
-	if (!orig && !other)
-		return NULL;
-	if (!orig) {
-		perf_cpu_map__get(other);
-		return other;
-	}
-	if (!other)
-		return orig;
-	if (orig->nr == other->nr &&
-	    !memcmp(orig->map, other->map, orig->nr * sizeof(struct perf_cpu)))
+	if (perf_cpu_map__is_subset(orig, other))
 		return orig;
+	if (perf_cpu_map__is_subset(other, orig)) {
+		perf_cpu_map__put(orig);
+		return perf_cpu_map__get(other);
+	}
 
 	tmp_len = orig->nr + other->nr;
 	tmp_cpus = malloc(tmp_len * sizeof(struct perf_cpu));
diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
index 9a770bfdc804..e6c98a6e3908 100644
--- a/tools/lib/perf/evlist.c
+++ b/tools/lib/perf/evlist.c
@@ -23,6 +23,7 @@
 #include <perf/cpumap.h>
 #include <perf/threadmap.h>
 #include <api/fd/array.h>
+#include "internal.h"
 
 void perf_evlist__init(struct perf_evlist *evlist)
 {
@@ -39,19 +40,23 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
 	 * We already have cpus for evsel (via PMU sysfs) so
 	 * keep it, if there's no target cpu list defined.
 	 */
-	if (!evsel->own_cpus || evlist->has_user_cpus) {
+	if (!evsel->own_cpus ||
+	    (!evsel->system_wide && evlist->has_user_cpus) ||
+	    (!evsel->system_wide &&
+	     !evsel->requires_cpu &&
+	     perf_cpu_map__empty(evlist->user_requested_cpus))) {
 		perf_cpu_map__put(evsel->cpus);
-		evsel->cpus = perf_cpu_map__get(evlist->cpus);
-	} else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) {
-		perf_cpu_map__put(evsel->cpus);
-		evsel->cpus = perf_cpu_map__get(evlist->cpus);
+		evsel->cpus = perf_cpu_map__get(evlist->user_requested_cpus);
 	} else if (evsel->cpus != evsel->own_cpus) {
 		perf_cpu_map__put(evsel->cpus);
 		evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
 	}
 
-	perf_thread_map__put(evsel->threads);
-	evsel->threads = perf_thread_map__get(evlist->threads);
+	if (!evsel->system_wide) {
+		perf_thread_map__put(evsel->threads);
+		evsel->threads = perf_thread_map__get(evlist->threads);
+	}
+
 	evlist->all_cpus = perf_cpu_map__merge(evlist->all_cpus, evsel->cpus);
 }
 
@@ -59,6 +64,10 @@ static void perf_evlist__propagate_maps(struct perf_evlist *evlist)
 {
 	struct perf_evsel *evsel;
 
+	/* Recomputing all_cpus, so start with a blank slate. */
+	perf_cpu_map__put(evlist->all_cpus);
+	evlist->all_cpus = NULL;
+
 	perf_evlist__for_each_evsel(evlist, evsel)
 		__perf_evlist__propagate_maps(evlist, evsel);
 }
@@ -123,10 +132,10 @@ static void perf_evlist__purge(struct perf_evlist *evlist)
 
 void perf_evlist__exit(struct perf_evlist *evlist)
 {
-	perf_cpu_map__put(evlist->cpus);
+	perf_cpu_map__put(evlist->user_requested_cpus);
 	perf_cpu_map__put(evlist->all_cpus);
 	perf_thread_map__put(evlist->threads);
-	evlist->cpus = NULL;
+	evlist->user_requested_cpus = NULL;
 	evlist->all_cpus = NULL;
 	evlist->threads = NULL;
 	fdarray__exit(&evlist->pollfd);
@@ -155,9 +164,9 @@ void perf_evlist__set_maps(struct perf_evlist *evlist,
 	 * original reference count of 1.  If that is not the case it is up to
 	 * the caller to increase the reference count.
 	 */
-	if (cpus != evlist->cpus) {
-		perf_cpu_map__put(evlist->cpus);
-		evlist->cpus = perf_cpu_map__get(cpus);
+	if (cpus != evlist->user_requested_cpus) {
+		perf_cpu_map__put(evlist->user_requested_cpus);
+		evlist->user_requested_cpus = perf_cpu_map__get(cpus);
 	}
 
 	if (threads != evlist->threads) {
@@ -294,7 +303,7 @@ add:
 
 int perf_evlist__alloc_pollfd(struct perf_evlist *evlist)
 {
-	int nr_cpus = perf_cpu_map__nr(evlist->cpus);
+	int nr_cpus = perf_cpu_map__nr(evlist->all_cpus);
 	int nr_threads = perf_thread_map__nr(evlist->threads);
 	int nfds = 0;
 	struct perf_evsel *evsel;
@@ -424,9 +433,9 @@ static void perf_evlist__set_mmap_first(struct perf_evlist *evlist, struct perf_
 static int
 mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
 	       int idx, struct perf_mmap_param *mp, int cpu_idx,
-	       int thread, int *_output, int *_output_overwrite)
+	       int thread, int *_output, int *_output_overwrite, int *nr_mmaps)
 {
-	struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->cpus, cpu_idx);
+	struct perf_cpu evlist_cpu = perf_cpu_map__cpu(evlist->all_cpus, cpu_idx);
 	struct perf_evsel *evsel;
 	int revent;
 
@@ -474,9 +483,14 @@ mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
 			 */
 			refcount_set(&map->refcnt, 2);
 
+			if (ops->idx)
+				ops->idx(evlist, evsel, mp, idx);
+
 			if (ops->mmap(map, mp, *output, evlist_cpu) < 0)
 				return -1;
 
+			*nr_mmaps += 1;
+
 			if (!idx)
 				perf_evlist__set_mmap_first(evlist, map, overwrite);
 		} else {
@@ -506,53 +520,28 @@ mmap_per_evsel(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
 }
 
 static int
-mmap_per_thread(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
-		struct perf_mmap_param *mp)
-{
-	int thread;
-	int nr_threads = perf_thread_map__nr(evlist->threads);
-
-	for (thread = 0; thread < nr_threads; thread++) {
-		int output = -1;
-		int output_overwrite = -1;
-
-		if (ops->idx)
-			ops->idx(evlist, mp, thread, false);
-
-		if (mmap_per_evsel(evlist, ops, thread, mp, 0, thread,
-				   &output, &output_overwrite))
-			goto out_unmap;
-	}
-
-	return 0;
-
-out_unmap:
-	perf_evlist__munmap(evlist);
-	return -1;
-}
-
-static int
 mmap_per_cpu(struct perf_evlist *evlist, struct perf_evlist_mmap_ops *ops,
 	     struct perf_mmap_param *mp)
 {
 	int nr_threads = perf_thread_map__nr(evlist->threads);
-	int nr_cpus    = perf_cpu_map__nr(evlist->cpus);
+	int nr_cpus    = perf_cpu_map__nr(evlist->all_cpus);
+	int nr_mmaps = 0;
 	int cpu, thread;
 
 	for (cpu = 0; cpu < nr_cpus; cpu++) {
 		int output = -1;
 		int output_overwrite = -1;
 
-		if (ops->idx)
-			ops->idx(evlist, mp, cpu, true);
-
 		for (thread = 0; thread < nr_threads; thread++) {
 			if (mmap_per_evsel(evlist, ops, cpu, mp, cpu,
-					   thread, &output, &output_overwrite))
+					   thread, &output, &output_overwrite, &nr_mmaps))
 				goto out_unmap;
 		}
 	}
 
+	if (nr_mmaps != evlist->nr_mmaps)
+		pr_err("Miscounted nr_mmaps %d vs %d\n", nr_mmaps, evlist->nr_mmaps);
+
 	return 0;
 
 out_unmap:
@@ -564,9 +553,14 @@ static int perf_evlist__nr_mmaps(struct perf_evlist *evlist)
 {
 	int nr_mmaps;
 
-	nr_mmaps = perf_cpu_map__nr(evlist->cpus);
-	if (perf_cpu_map__empty(evlist->cpus))
-		nr_mmaps = perf_thread_map__nr(evlist->threads);
+	/* One for each CPU */
+	nr_mmaps = perf_cpu_map__nr(evlist->all_cpus);
+	if (perf_cpu_map__empty(evlist->all_cpus)) {
+		/* Plus one for each thread */
+		nr_mmaps += perf_thread_map__nr(evlist->threads);
+		/* Minus the per-thread CPU (-1) */
+		nr_mmaps -= 1;
+	}
 
 	return nr_mmaps;
 }
@@ -576,8 +570,6 @@ int perf_evlist__mmap_ops(struct perf_evlist *evlist,
 			  struct perf_mmap_param *mp)
 {
 	struct perf_evsel *evsel;
-	const struct perf_cpu_map *cpus = evlist->cpus;
-	const struct perf_thread_map *threads = evlist->threads;
 
 	if (!ops || !ops->get || !ops->mmap)
 		return -EINVAL;
@@ -589,16 +581,13 @@ int perf_evlist__mmap_ops(struct perf_evlist *evlist,
 	perf_evlist__for_each_entry(evlist, evsel) {
 		if ((evsel->attr.read_format & PERF_FORMAT_ID) &&
 		    evsel->sample_id == NULL &&
-		    perf_evsel__alloc_id(evsel, perf_cpu_map__nr(cpus), threads->nr) < 0)
+		    perf_evsel__alloc_id(evsel, evsel->fd->max_x, evsel->fd->max_y) < 0)
 			return -ENOMEM;
 	}
 
 	if (evlist->pollfd.entries == NULL && perf_evlist__alloc_pollfd(evlist) < 0)
 		return -ENOMEM;
 
-	if (perf_cpu_map__empty(cpus))
-		return mmap_per_thread(evlist, ops, mp);
-
 	return mmap_per_cpu(evlist, ops, mp);
 }
 
diff --git a/tools/lib/perf/evsel.c b/tools/lib/perf/evsel.c
index 210ea7c06ce8..952f3520d5c2 100644
--- a/tools/lib/perf/evsel.c
+++ b/tools/lib/perf/evsel.c
@@ -149,23 +149,30 @@ int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus,
 			int fd, group_fd, *evsel_fd;
 
 			evsel_fd = FD(evsel, idx, thread);
-			if (evsel_fd == NULL)
-				return -EINVAL;
+			if (evsel_fd == NULL) {
+				err = -EINVAL;
+				goto out;
+			}
 
 			err = get_group_fd(evsel, idx, thread, &group_fd);
 			if (err < 0)
-				return err;
+				goto out;
 
 			fd = sys_perf_event_open(&evsel->attr,
 						 threads->map[thread].pid,
 						 cpu, group_fd, 0);
 
-			if (fd < 0)
-				return -errno;
+			if (fd < 0) {
+				err = -errno;
+				goto out;
+			}
 
 			*evsel_fd = fd;
 		}
 	}
+out:
+	if (err)
+		perf_evsel__close(evsel);
 
 	return err;
 }
@@ -328,6 +335,17 @@ int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int thread,
 	return 0;
 }
 
+static int perf_evsel__ioctl(struct perf_evsel *evsel, int ioc, void *arg,
+			     int cpu_map_idx, int thread)
+{
+	int *fd = FD(evsel, cpu_map_idx, thread);
+
+	if (fd == NULL || *fd < 0)
+		return -1;
+
+	return ioctl(*fd, ioc, arg);
+}
+
 static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
 				 int ioc,  void *arg,
 				 int cpu_map_idx)
@@ -335,13 +353,7 @@ static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
 	int thread;
 
 	for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
-		int err;
-		int *fd = FD(evsel, cpu_map_idx, thread);
-
-		if (fd == NULL || *fd < 0)
-			return -1;
-
-		err = ioctl(*fd, ioc, arg);
+		int err = perf_evsel__ioctl(evsel, ioc, arg, cpu_map_idx, thread);
 
 		if (err)
 			return err;
@@ -355,6 +367,21 @@ int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx)
 	return perf_evsel__run_ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, cpu_map_idx);
 }
 
+int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread)
+{
+	struct perf_cpu cpu __maybe_unused;
+	int idx;
+	int err;
+
+	perf_cpu_map__for_each_cpu(cpu, idx, evsel->cpus) {
+		err = perf_evsel__ioctl(evsel, PERF_EVENT_IOC_ENABLE, NULL, idx, thread);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
 int perf_evsel__enable(struct perf_evsel *evsel)
 {
 	int i;
diff --git a/tools/lib/perf/include/internal/cpumap.h b/tools/lib/perf/include/internal/cpumap.h
index 1973a18c096b..35dd29642296 100644
--- a/tools/lib/perf/include/internal/cpumap.h
+++ b/tools/lib/perf/include/internal/cpumap.h
@@ -25,5 +25,6 @@ struct perf_cpu_map {
 #endif
 
 int perf_cpu_map__idx(const struct perf_cpu_map *cpus, struct perf_cpu cpu);
+bool perf_cpu_map__is_subset(const struct perf_cpu_map *a, const struct perf_cpu_map *b);
 
 #endif /* __LIBPERF_INTERNAL_CPUMAP_H */
diff --git a/tools/lib/perf/include/internal/evlist.h b/tools/lib/perf/include/internal/evlist.h
index 4cefade540bd..6f89aec3e608 100644
--- a/tools/lib/perf/include/internal/evlist.h
+++ b/tools/lib/perf/include/internal/evlist.h
@@ -19,7 +19,12 @@ struct perf_evlist {
 	int			 nr_entries;
 	int			 nr_groups;
 	bool			 has_user_cpus;
-	struct perf_cpu_map	*cpus;
+	/**
+	 * The cpus passed from the command line or all online CPUs by
+	 * default.
+	 */
+	struct perf_cpu_map	*user_requested_cpus;
+	/** The union of all evsel cpu maps. */
 	struct perf_cpu_map	*all_cpus;
 	struct perf_thread_map	*threads;
 	int			 nr_mmaps;
@@ -33,7 +38,8 @@ struct perf_evlist {
 };
 
 typedef void
-(*perf_evlist_mmap__cb_idx_t)(struct perf_evlist*, struct perf_mmap_param*, int, bool);
+(*perf_evlist_mmap__cb_idx_t)(struct perf_evlist*, struct perf_evsel*,
+			      struct perf_mmap_param*, int);
 typedef struct perf_mmap*
 (*perf_evlist_mmap__cb_get_t)(struct perf_evlist*, bool, int);
 typedef int
diff --git a/tools/lib/perf/include/internal/evsel.h b/tools/lib/perf/include/internal/evsel.h
index cfc9ebd7968e..2a912a1f1989 100644
--- a/tools/lib/perf/include/internal/evsel.h
+++ b/tools/lib/perf/include/internal/evsel.h
@@ -49,7 +49,18 @@ struct perf_evsel {
 
 	/* parse modifier helper */
 	int			 nr_members;
+	/*
+	 * system_wide is for events that need to be on every CPU, irrespective
+	 * of user requested CPUs or threads. Map propagation will set cpus to
+	 * this event's own_cpus, whereby they will contribute to evlist
+	 * all_cpus.
+	 */
 	bool			 system_wide;
+	/*
+	 * Some events, for example uncore events, require a CPU.
+	 * i.e. it cannot be the 'any CPU' value of -1.
+	 */
+	bool			 requires_cpu;
 	int			 idx;
 };
 
diff --git a/tools/lib/perf/include/internal/lib.h b/tools/lib/perf/include/internal/lib.h
index 5175d491b2d4..85471a4b900f 100644
--- a/tools/lib/perf/include/internal/lib.h
+++ b/tools/lib/perf/include/internal/lib.h
@@ -9,4 +9,6 @@ extern unsigned int page_size;
 ssize_t readn(int fd, void *buf, size_t n);
 ssize_t writen(int fd, const void *buf, size_t n);
 
+ssize_t preadn(int fd, void *buf, size_t n, off_t offs);
+
 #endif /* __LIBPERF_INTERNAL_CPUMAP_H */
diff --git a/tools/lib/perf/include/perf/cpumap.h b/tools/lib/perf/include/perf/cpumap.h
index 4a2edbdb5e2b..24de795b09bb 100644
--- a/tools/lib/perf/include/perf/cpumap.h
+++ b/tools/lib/perf/include/perf/cpumap.h
@@ -31,4 +31,7 @@ LIBPERF_API bool perf_cpu_map__has(const struct perf_cpu_map *map, struct perf_c
 	     (idx) < perf_cpu_map__nr(cpus);			\
 	     (idx)++, (cpu) = perf_cpu_map__cpu(cpus, idx))
 
+#define perf_cpu_map__for_each_idx(idx, cpus)				\
+	for ((idx) = 0; (idx) < perf_cpu_map__nr(cpus); (idx)++)
+
 #endif /* __LIBPERF_CPUMAP_H */
diff --git a/tools/lib/perf/include/perf/event.h b/tools/lib/perf/include/perf/event.h
index 75ee385fb078..e7758707cadd 100644
--- a/tools/lib/perf/include/perf/event.h
+++ b/tools/lib/perf/include/perf/event.h
@@ -240,7 +240,7 @@ struct id_index_entry {
 struct perf_record_id_index {
 	struct perf_event_header header;
 	__u64			 nr;
-	struct id_index_entry	 entries[0];
+	struct id_index_entry	 entries[];
 };
 
 struct perf_record_auxtrace_info {
diff --git a/tools/lib/perf/include/perf/evsel.h b/tools/lib/perf/include/perf/evsel.h
index 2a9516b42d15..699c0ed97d34 100644
--- a/tools/lib/perf/include/perf/evsel.h
+++ b/tools/lib/perf/include/perf/evsel.h
@@ -36,6 +36,7 @@ LIBPERF_API int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int
 				 struct perf_counts_values *count);
 LIBPERF_API int perf_evsel__enable(struct perf_evsel *evsel);
 LIBPERF_API int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
+LIBPERF_API int perf_evsel__enable_thread(struct perf_evsel *evsel, int thread);
 LIBPERF_API int perf_evsel__disable(struct perf_evsel *evsel);
 LIBPERF_API int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx);
 LIBPERF_API struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel);
diff --git a/tools/lib/perf/include/perf/threadmap.h b/tools/lib/perf/include/perf/threadmap.h
index a7c50de8d010..8b40e7777cea 100644
--- a/tools/lib/perf/include/perf/threadmap.h
+++ b/tools/lib/perf/include/perf/threadmap.h
@@ -8,11 +8,12 @@
 struct perf_thread_map;
 
 LIBPERF_API struct perf_thread_map *perf_thread_map__new_dummy(void);
+LIBPERF_API struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array);
 
-LIBPERF_API void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid);
-LIBPERF_API char *perf_thread_map__comm(struct perf_thread_map *map, int thread);
+LIBPERF_API void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid);
+LIBPERF_API char *perf_thread_map__comm(struct perf_thread_map *map, int idx);
 LIBPERF_API int perf_thread_map__nr(struct perf_thread_map *threads);
-LIBPERF_API pid_t perf_thread_map__pid(struct perf_thread_map *map, int thread);
+LIBPERF_API pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx);
 
 LIBPERF_API struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map);
 LIBPERF_API void perf_thread_map__put(struct perf_thread_map *map);
diff --git a/tools/lib/perf/lib.c b/tools/lib/perf/lib.c
index 18658931fc71..696fb0ea67c6 100644
--- a/tools/lib/perf/lib.c
+++ b/tools/lib/perf/lib.c
@@ -38,6 +38,26 @@ ssize_t readn(int fd, void *buf, size_t n)
 	return ion(true, fd, buf, n);
 }
 
+ssize_t preadn(int fd, void *buf, size_t n, off_t offs)
+{
+	size_t left = n;
+
+	while (left) {
+		ssize_t ret = pread(fd, buf, left, offs);
+
+		if (ret < 0 && errno == EINTR)
+			continue;
+		if (ret <= 0)
+			return ret;
+
+		left -= ret;
+		buf  += ret;
+		offs += ret;
+	}
+
+	return n;
+}
+
 /*
  * Write exactly 'n' bytes or return an error.
  */
diff --git a/tools/lib/perf/libperf.map b/tools/lib/perf/libperf.map
index 6fa0d651576b..190b56ae923a 100644
--- a/tools/lib/perf/libperf.map
+++ b/tools/lib/perf/libperf.map
@@ -12,6 +12,7 @@ LIBPERF_0.0.1 {
 		perf_cpu_map__empty;
 		perf_cpu_map__max;
 		perf_cpu_map__has;
+		perf_thread_map__new_array;
 		perf_thread_map__new_dummy;
 		perf_thread_map__set_pid;
 		perf_thread_map__comm;
diff --git a/tools/lib/perf/tests/test-evlist.c b/tools/lib/perf/tests/test-evlist.c
index fa854c83b7e7..ed616fc19b4f 100644
--- a/tools/lib/perf/tests/test-evlist.c
+++ b/tools/lib/perf/tests/test-evlist.c
@@ -69,7 +69,7 @@ static int test_stat_cpu(void)
 	perf_evlist__set_maps(evlist, cpus, NULL);
 
 	err = perf_evlist__open(evlist);
-	__T("failed to open evsel", err == 0);
+	__T("failed to open evlist", err == 0);
 
 	perf_evlist__for_each_evsel(evlist, evsel) {
 		cpus = perf_evsel__cpus(evsel);
@@ -130,7 +130,7 @@ static int test_stat_thread(void)
 	perf_evlist__set_maps(evlist, NULL, threads);
 
 	err = perf_evlist__open(evlist);
-	__T("failed to open evsel", err == 0);
+	__T("failed to open evlist", err == 0);
 
 	perf_evlist__for_each_evsel(evlist, evsel) {
 		perf_evsel__read(evsel, 0, 0, &counts);
@@ -187,7 +187,7 @@ static int test_stat_thread_enable(void)
 	perf_evlist__set_maps(evlist, NULL, threads);
 
 	err = perf_evlist__open(evlist);
-	__T("failed to open evsel", err == 0);
+	__T("failed to open evlist", err == 0);
 
 	perf_evlist__for_each_evsel(evlist, evsel) {
 		perf_evsel__read(evsel, 0, 0, &counts);
@@ -507,7 +507,7 @@ static int test_stat_multiplexing(void)
 	perf_evlist__set_maps(evlist, NULL, threads);
 
 	err = perf_evlist__open(evlist);
-	__T("failed to open evsel", err == 0);
+	__T("failed to open evlist", err == 0);
 
 	perf_evlist__enable(evlist);
 
diff --git a/tools/lib/perf/tests/test-threadmap.c b/tools/lib/perf/tests/test-threadmap.c
index 5e2a0291e94c..f728ad7002bb 100644
--- a/tools/lib/perf/tests/test-threadmap.c
+++ b/tools/lib/perf/tests/test-threadmap.c
@@ -11,9 +11,43 @@ static int libperf_print(enum libperf_print_level level,
 	return vfprintf(stderr, fmt, ap);
 }
 
+static int test_threadmap_array(int nr, pid_t *array)
+{
+	struct perf_thread_map *threads;
+	int i;
+
+	threads = perf_thread_map__new_array(nr, array);
+	__T("Failed to allocate new thread map", threads);
+
+	__T("Unexpected number of threads", perf_thread_map__nr(threads) == nr);
+
+	for (i = 0; i < nr; i++) {
+		__T("Unexpected initial value of thread",
+		    perf_thread_map__pid(threads, i) == (array ? array[i] : -1));
+	}
+
+	for (i = 1; i < nr; i++)
+		perf_thread_map__set_pid(threads, i, i * 100);
+
+	__T("Unexpected value of thread 0",
+	    perf_thread_map__pid(threads, 0) == (array ? array[0] : -1));
+
+	for (i = 1; i < nr; i++) {
+		__T("Unexpected thread value",
+		    perf_thread_map__pid(threads, i) == i * 100);
+	}
+
+	perf_thread_map__put(threads);
+
+	return 0;
+}
+
+#define THREADS_NR	10
 int test_threadmap(int argc, char **argv)
 {
 	struct perf_thread_map *threads;
+	pid_t thr_array[THREADS_NR];
+	int i;
 
 	__T_START;
 
@@ -27,6 +61,13 @@ int test_threadmap(int argc, char **argv)
 	perf_thread_map__put(threads);
 	perf_thread_map__put(threads);
 
+	test_threadmap_array(THREADS_NR, NULL);
+
+	for (i = 0; i < THREADS_NR; i++)
+		thr_array[i] = i + 100;
+
+	test_threadmap_array(THREADS_NR, thr_array);
+
 	__T_END;
 	return tests_failed == 0 ? 0 : -1;
 }
diff --git a/tools/lib/perf/threadmap.c b/tools/lib/perf/threadmap.c
index e92c368b0a6c..07968f3ea093 100644
--- a/tools/lib/perf/threadmap.c
+++ b/tools/lib/perf/threadmap.c
@@ -32,28 +32,38 @@ struct perf_thread_map *perf_thread_map__realloc(struct perf_thread_map *map, in
 
 #define thread_map__alloc(__nr) perf_thread_map__realloc(NULL, __nr)
 
-void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid)
+void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid)
 {
-	map->map[thread].pid = pid;
+	map->map[idx].pid = pid;
 }
 
-char *perf_thread_map__comm(struct perf_thread_map *map, int thread)
+char *perf_thread_map__comm(struct perf_thread_map *map, int idx)
 {
-	return map->map[thread].comm;
+	return map->map[idx].comm;
 }
 
-struct perf_thread_map *perf_thread_map__new_dummy(void)
+struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array)
 {
-	struct perf_thread_map *threads = thread_map__alloc(1);
+	struct perf_thread_map *threads = thread_map__alloc(nr_threads);
+	int i;
+
+	if (!threads)
+		return NULL;
+
+	for (i = 0; i < nr_threads; i++)
+		perf_thread_map__set_pid(threads, i, array ? array[i] : -1);
+
+	threads->nr = nr_threads;
+	refcount_set(&threads->refcnt, 1);
 
-	if (threads != NULL) {
-		perf_thread_map__set_pid(threads, 0, -1);
-		threads->nr = 1;
-		refcount_set(&threads->refcnt, 1);
-	}
 	return threads;
 }
 
+struct perf_thread_map *perf_thread_map__new_dummy(void)
+{
+	return perf_thread_map__new_array(1, NULL);
+}
+
 static void perf_thread_map__delete(struct perf_thread_map *threads)
 {
 	if (threads) {
@@ -85,7 +95,7 @@ int perf_thread_map__nr(struct perf_thread_map *threads)
 	return threads ? threads->nr : 1;
 }
 
-pid_t perf_thread_map__pid(struct perf_thread_map *map, int thread)
+pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx)
 {
-	return map->map[thread].pid;
+	return map->map[idx].pid;
 }