Merge tag 'perf-core-for-mingo-20160523' of...

Merge tag 'perf-core-for-mingo-20160523' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/core improvements from Arnaldo Carvalho de Melo:

User visible changes:

- Add "srcline_from" and "srcline_to" branch sort keys to 'perf top' and
  'perf report' (Andi Kleen)

Infrastructure changes:

- Make 'perf trace' auto-attach fd->name and ptr->name beautifiers based
  on the name of syscall arguments, this way new syscalls that have
  'const char * (path,pathname,filename)' will use the fd->name beautifier
  (vfs_getname perf probe, if in place) and the 'fd->name' (vfs_getname
  or via /proc/PID/fd/) (Arnaldo Carvalho de Melo)

- Infrastructure to read from a ring buffer in backward write mode (Wang Nan)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/perf/Documentation/perf-report.txt

@@ -103,12 +103,13 @@ OPTIONS
 
 	If --branch-stack option is used, following sort keys are also
 	available:
-	dso_from, dso_to, symbol_from, symbol_to, mispredict.
 
 	- dso_from: name of library or module branched from
 	- dso_to: name of library or module branched to
 	- symbol_from: name of function branched from
 	- symbol_to: name of function branched to
+	- srcline_from: source file and line branched from
+	- srcline_to: source file and line branched to
 	- mispredict: "N" for predicted branch, "Y" for mispredicted branch
 	- in_tx: branch in TSX transaction
 	- abort: TSX transaction abort.

tools/perf/builtin-record.c

@@ -40,6 +40,7 @@
 #include <unistd.h>
 #include <sched.h>
 #include <sys/mman.h>
+#include <asm/bug.h>
 
 
 struct record {
@@ -82,27 +83,87 @@ static int process_synthesized_event(struct perf_tool *tool,
 	return record__write(rec, event, event->header.size);
 }
 
+static int
+backward_rb_find_range(void *buf, int mask, u64 head, u64 *start, u64 *end)
+{
+	struct perf_event_header *pheader;
+	u64 evt_head = head;
+	int size = mask + 1;
+
+	pr_debug2("backward_rb_find_range: buf=%p, head=%"PRIx64"\n", buf, head);
+	pheader = (struct perf_event_header *)(buf + (head & mask));
+	*start = head;
+	while (true) {
+		if (evt_head - head >= (unsigned int)size) {
+			pr_debug("Finshed reading backward ring buffer: rewind\n");
+			if (evt_head - head > (unsigned int)size)
+				evt_head -= pheader->size;
+			*end = evt_head;
+			return 0;
+		}
+
+		pheader = (struct perf_event_header *)(buf + (evt_head & mask));
+
+		if (pheader->size == 0) {
+			pr_debug("Finshed reading backward ring buffer: get start\n");
+			*end = evt_head;
+			return 0;
+		}
+
+		evt_head += pheader->size;
+		pr_debug3("move evt_head: %"PRIx64"\n", evt_head);
+	}
+	WARN_ONCE(1, "Shouldn't get here\n");
+	return -1;
+}
+
+static int
+rb_find_range(struct perf_evlist *evlist,
+	      void *data, int mask, u64 head, u64 old,
+	      u64 *start, u64 *end)
+{
+	if (!evlist->backward) {
+		*start = old;
+		*end = head;
+		return 0;
+	}
+
+	return backward_rb_find_range(data, mask, head, start, end);
+}
+
 static int record__mmap_read(struct record *rec, int idx)
 {
 	struct perf_mmap *md = &rec->evlist->mmap[idx];
 	u64 head = perf_mmap__read_head(md);
 	u64 old = md->prev;
+	u64 end = head, start = old;
 	unsigned char *data = md->base + page_size;
 	unsigned long size;
 	void *buf;
 	int rc = 0;
 
-	if (old == head)
+	if (rb_find_range(rec->evlist, data, md->mask, head,
+			  old, &start, &end))
+		return -1;
+
+	if (start == end)
 		return 0;
 
 	rec->samples++;
 
-	size = head - old;
+	size = end - start;
+	if (size > (unsigned long)(md->mask) + 1) {
+		WARN_ONCE(1, "failed to keep up with mmap data. (warn only once)\n");
+
+		md->prev = head;
+		perf_evlist__mmap_consume(rec->evlist, idx);
+		return 0;
+	}
 
-	if ((old & md->mask) + size != (head & md->mask)) {
-		buf = &data[old & md->mask];
-		size = md->mask + 1 - (old & md->mask);
-		old += size;
+	if ((start & md->mask) + size != (end & md->mask)) {
+		buf = &data[start & md->mask];
+		size = md->mask + 1 - (start & md->mask);
+		start += size;
 
 		if (record__write(rec, buf, size) < 0) {
 			rc = -1;
@@ -110,16 +171,16 @@ static int record__mmap_read(struct record *rec, int idx)
 		}
 	}
 
-	buf = &data[old & md->mask];
-	size = head - old;
-	old += size;
+	buf = &data[start & md->mask];
+	size = end - start;
+	start += size;
 
 	if (record__write(rec, buf, size) < 0) {
 		rc = -1;
 		goto out;
 	}
 
-	md->prev = old;
+	md->prev = head;
 	perf_evlist__mmap_consume(rec->evlist, idx);
 out:
 	return rc;

tools/perf/util/evlist.c

@@ -44,6 +44,7 @@ void perf_evlist__init(struct perf_evlist *evlist, struct cpu_map *cpus,
 	perf_evlist__set_maps(evlist, cpus, threads);
 	fdarray__init(&evlist->pollfd, 64);
 	evlist->workload.pid = -1;
+	evlist->backward = false;
 }
 
 struct perf_evlist *perf_evlist__new(void)
@@ -679,6 +680,33 @@ static struct perf_evsel *perf_evlist__event2evsel(struct perf_evlist *evlist,
 	return NULL;
 }
 
+static int perf_evlist__set_paused(struct perf_evlist *evlist, bool value)
+{
+	int i;
+
+	for (i = 0; i < evlist->nr_mmaps; i++) {
+		int fd = evlist->mmap[i].fd;
+		int err;
+
+		if (fd < 0)
+			continue;
+		err = ioctl(fd, PERF_EVENT_IOC_PAUSE_OUTPUT, value ? 1 : 0);
+		if (err)
+			return err;
+	}
+	return 0;
+}
+
+int perf_evlist__pause(struct perf_evlist *evlist)
+{
+	return perf_evlist__set_paused(evlist, true);
+}
+
+int perf_evlist__resume(struct perf_evlist *evlist)
+{
+	return perf_evlist__set_paused(evlist, false);
+}
+
 /* When check_messup is true, 'end' must points to a good entry */
 static union perf_event *
 perf_mmap__read(struct perf_mmap *md, bool check_messup, u64 start,
@@ -881,6 +909,7 @@ static void __perf_evlist__munmap(struct perf_evlist *evlist, int idx)
 	if (evlist->mmap[idx].base != NULL) {
 		munmap(evlist->mmap[idx].base, evlist->mmap_len);
 		evlist->mmap[idx].base = NULL;
+		evlist->mmap[idx].fd = -1;
 		atomic_set(&evlist->mmap[idx].refcnt, 0);
 	}
 	auxtrace_mmap__munmap(&evlist->mmap[idx].auxtrace_mmap);
@@ -901,10 +930,14 @@ void perf_evlist__munmap(struct perf_evlist *evlist)
 
 static int perf_evlist__alloc_mmap(struct perf_evlist *evlist)
 {
+	int i;
+
 	evlist->nr_mmaps = cpu_map__nr(evlist->cpus);
 	if (cpu_map__empty(evlist->cpus))
 		evlist->nr_mmaps = thread_map__nr(evlist->threads);
 	evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap));
+	for (i = 0; i < evlist->nr_mmaps; i++)
+		evlist->mmap[i].fd = -1;
 	return evlist->mmap != NULL ? 0 : -ENOMEM;
 }
 
@@ -941,6 +974,7 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist, int idx,
 		evlist->mmap[idx].base = NULL;
 		return -1;
 	}
+	evlist->mmap[idx].fd = fd;
 
 	if (auxtrace_mmap__mmap(&evlist->mmap[idx].auxtrace_mmap,
 				&mp->auxtrace_mp, evlist->mmap[idx].base, fd))

tools/perf/util/evlist.h

@@ -28,6 +28,7 @@ struct record_opts;
 struct perf_mmap {
 	void		 *base;
 	int		 mask;
+	int		 fd;
 	atomic_t	 refcnt;
 	u64		 prev;
 	struct auxtrace_mmap auxtrace_mmap;
@@ -43,6 +44,7 @@ struct perf_evlist {
 	bool		 overwrite;
 	bool		 enabled;
 	bool		 has_user_cpus;
+	bool		 backward;
 	size_t		 mmap_len;
 	int		 id_pos;
 	int		 is_pos;
@@ -135,6 +137,8 @@ void perf_evlist__mmap_read_catchup(struct perf_evlist *evlist, int idx);
 
 void perf_evlist__mmap_consume(struct perf_evlist *evlist, int idx);
 
+int perf_evlist__pause(struct perf_evlist *evlist);
+int perf_evlist__resume(struct perf_evlist *evlist);
 int perf_evlist__open(struct perf_evlist *evlist);
 void perf_evlist__close(struct perf_evlist *evlist);
 

tools/perf/util/evsel.c

@@ -37,6 +37,7 @@ static struct {
 	bool clockid;
 	bool clockid_wrong;
 	bool lbr_flags;
+	bool write_backward;
 } perf_missing_features;
 
 static clockid_t clockid;
@@ -1376,6 +1377,8 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 	if (perf_missing_features.lbr_flags)
 		evsel->attr.branch_sample_type &= ~(PERF_SAMPLE_BRANCH_NO_FLAGS |
 				     PERF_SAMPLE_BRANCH_NO_CYCLES);
+	if (perf_missing_features.write_backward)
+		evsel->attr.write_backward = false;
 retry_sample_id:
 	if (perf_missing_features.sample_id_all)
 		evsel->attr.sample_id_all = 0;
@@ -1438,6 +1441,12 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 				err = -EINVAL;
 				goto out_close;
 			}
+
+			if (evsel->overwrite &&
+			    perf_missing_features.write_backward) {
+				err = -EINVAL;
+				goto out_close;
+			}
 		}
 	}
 
@@ -1500,6 +1509,10 @@ static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
 			  PERF_SAMPLE_BRANCH_NO_FLAGS))) {
 		perf_missing_features.lbr_flags = true;
 		goto fallback_missing_features;
+	} else if (!perf_missing_features.write_backward &&
+			evsel->attr.write_backward) {
+		perf_missing_features.write_backward = true;
+		goto fallback_missing_features;
 	}
 
 out_close:

tools/perf/util/evsel.h

@@ -112,6 +112,7 @@ struct perf_evsel {
 	bool			tracking;
 	bool			per_pkg;
 	bool			precise_max;
+	bool			overwrite;
 	/* parse modifier helper */
 	int			exclude_GH;
 	int			nr_members;

tools/perf/util/hist.c

@@ -117,6 +117,13 @@ void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
 			hists__new_col_len(hists, HISTC_SYMBOL_TO, symlen);
 			hists__set_unres_dso_col_len(hists, HISTC_DSO_TO);
 		}
+
+		if (h->branch_info->srcline_from)
+			hists__new_col_len(hists, HISTC_SRCLINE_FROM,
+					strlen(h->branch_info->srcline_from));
+		if (h->branch_info->srcline_to)
+			hists__new_col_len(hists, HISTC_SRCLINE_TO,
+					strlen(h->branch_info->srcline_to));
 	}
 
 	if (h->mem_info) {
@@ -1042,6 +1049,8 @@ void hist_entry__delete(struct hist_entry *he)
 	if (he->branch_info) {
 		map__zput(he->branch_info->from.map);
 		map__zput(he->branch_info->to.map);
+		free_srcline(he->branch_info->srcline_from);
+		free_srcline(he->branch_info->srcline_to);
 		zfree(&he->branch_info);
 	}
 

tools/perf/util/hist.h

@@ -52,6 +52,8 @@ enum hist_column {
 	HISTC_MEM_IADDR_SYMBOL,
 	HISTC_TRANSACTION,
 	HISTC_CYCLES,
+	HISTC_SRCLINE_FROM,
+	HISTC_SRCLINE_TO,
 	HISTC_TRACE,
 	HISTC_NR_COLS, /* Last entry */
 };

tools/perf/util/sort.c

@@ -353,6 +353,88 @@ struct sort_entry sort_srcline = {
 	.se_width_idx	= HISTC_SRCLINE,
 };
 
+/* --sort srcline_from */
+
+static int64_t
+sort__srcline_from_cmp(struct hist_entry *left, struct hist_entry *right)
+{
+	if (!left->branch_info->srcline_from) {
+		struct map *map = left->branch_info->from.map;
+		if (!map)
+			left->branch_info->srcline_from = SRCLINE_UNKNOWN;
+		else
+			left->branch_info->srcline_from = get_srcline(map->dso,
+					   map__rip_2objdump(map,
+							     left->branch_info->from.al_addr),
+							 left->branch_info->from.sym, true);
+	}
+	if (!right->branch_info->srcline_from) {
+		struct map *map = right->branch_info->from.map;
+		if (!map)
+			right->branch_info->srcline_from = SRCLINE_UNKNOWN;
+		else
+			right->branch_info->srcline_from = get_srcline(map->dso,
+					     map__rip_2objdump(map,
+							       right->branch_info->from.al_addr),
+						     right->branch_info->from.sym, true);
+	}
+	return strcmp(right->branch_info->srcline_from, left->branch_info->srcline_from);
+}
+
+static int hist_entry__srcline_from_snprintf(struct hist_entry *he, char *bf,
+					size_t size, unsigned int width)
+{
+	return repsep_snprintf(bf, size, "%-*.*s", width, width, he->branch_info->srcline_from);
+}
+
+struct sort_entry sort_srcline_from = {
+	.se_header	= "From Source:Line",
+	.se_cmp		= sort__srcline_from_cmp,
+	.se_snprintf	= hist_entry__srcline_from_snprintf,
+	.se_width_idx	= HISTC_SRCLINE_FROM,
+};
+
+/* --sort srcline_to */
+
+static int64_t
+sort__srcline_to_cmp(struct hist_entry *left, struct hist_entry *right)
+{
+	if (!left->branch_info->srcline_to) {
+		struct map *map = left->branch_info->to.map;
+		if (!map)
+			left->branch_info->srcline_to = SRCLINE_UNKNOWN;
+		else
+			left->branch_info->srcline_to = get_srcline(map->dso,
+					   map__rip_2objdump(map,
+							     left->branch_info->to.al_addr),
+							 left->branch_info->from.sym, true);
+	}
+	if (!right->branch_info->srcline_to) {
+		struct map *map = right->branch_info->to.map;
+		if (!map)
+			right->branch_info->srcline_to = SRCLINE_UNKNOWN;
+		else
+			right->branch_info->srcline_to = get_srcline(map->dso,
+					     map__rip_2objdump(map,
+							       right->branch_info->to.al_addr),
+						     right->branch_info->to.sym, true);
+	}
+	return strcmp(right->branch_info->srcline_to, left->branch_info->srcline_to);
+}
+
+static int hist_entry__srcline_to_snprintf(struct hist_entry *he, char *bf,
+					size_t size, unsigned int width)
+{
+	return repsep_snprintf(bf, size, "%-*.*s", width, width, he->branch_info->srcline_to);
+}
+
+struct sort_entry sort_srcline_to = {
+	.se_header	= "To Source:Line",
+	.se_cmp		= sort__srcline_to_cmp,
+	.se_snprintf	= hist_entry__srcline_to_snprintf,
+	.se_width_idx	= HISTC_SRCLINE_TO,
+};
+
 /* --sort srcfile */
 
 static char no_srcfile[1];
@@ -1347,6 +1429,8 @@ static struct sort_dimension bstack_sort_dimensions[] = {
 	DIM(SORT_IN_TX, "in_tx", sort_in_tx),
 	DIM(SORT_ABORT, "abort", sort_abort),
 	DIM(SORT_CYCLES, "cycles", sort_cycles),
+	DIM(SORT_SRCLINE_FROM, "srcline_from", sort_srcline_from),
+	DIM(SORT_SRCLINE_TO, "srcline_to", sort_srcline_to),
 };
 
 #undef DIM

tools/perf/util/sort.h

@@ -215,6 +215,8 @@ enum sort_type {
 	SORT_ABORT,
 	SORT_IN_TX,
 	SORT_CYCLES,
+	SORT_SRCLINE_FROM,
+	SORT_SRCLINE_TO,
 
 	/* memory mode specific sort keys */
 	__SORT_MEMORY_MODE,

tools/perf/util/symbol.h

@@ -186,6 +186,8 @@ struct branch_info {
 	struct addr_map_symbol from;
 	struct addr_map_symbol to;
 	struct branch_flags flags;
+	char			*srcline_from;
+	char			*srcline_to;
 };
 
 struct mem_info {