Merge tag 'perf-core-for-mingo-20160510' of git://git.kernel.org/pub/…

…scm/linux/kernel/git/acme/linux into perf/core Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo: User visible changes: - Recording 'dwarf' callchains do not need DWARF unwinding support (He Kuang) - Print recently added perf_event_attr.write_backward bit flag in -vv verbose mode (Arnaldo Carvalho de Melo) - Fix incorrect python db-export error message in 'perf script' (Chris Phlipot) - Fix handling of zero-length symbols (Chris Phlipot) - perf stat: Scale values by unit before metrics (Andi Kleen) Infrastructure changes: - Rewrite strbuf not to die(), making tools using it to check its return value instead (Masami Hiramatsu) - Support reading from backward ring buffer, add a 'perf test' entry for it (Wang Nan) Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
torvalds · May 11, 2016 · 38f5d8b · 38f5d8b
2 parents d295015 + 452e840
commit 38f5d8b
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Showing 27 changed files with 510 additions and 245 deletions.
diff --git a/tools/perf/builtin-help.c b/tools/perf/builtin-help.c
@@ -61,6 +61,7 @@ static int check_emacsclient_version(void)
 	struct child_process ec_process;
 	const char *argv_ec[] = { "emacsclient", "--version", NULL };
 	int version;
+	int ret = -1;
 
 	/* emacsclient prints its version number on stderr */
 	memset(&ec_process, 0, sizeof(ec_process));
@@ -71,7 +72,10 @@ static int check_emacsclient_version(void)
 		fprintf(stderr, "Failed to start emacsclient.\n");
 		return -1;
 	}
-	strbuf_read(&buffer, ec_process.err, 20);
+	if (strbuf_read(&buffer, ec_process.err, 20) < 0) {
+		fprintf(stderr, "Failed to read emacsclient version\n");
+		goto out;
+	}
 	close(ec_process.err);
 
 	/*
@@ -82,8 +86,7 @@ static int check_emacsclient_version(void)
 
 	if (prefixcmp(buffer.buf, "emacsclient")) {
 		fprintf(stderr, "Failed to parse emacsclient version.\n");
-		strbuf_release(&buffer);
-		return -1;
+		goto out;
 	}
 
 	version = atoi(buffer.buf + strlen("emacsclient"));
@@ -92,12 +95,11 @@ static int check_emacsclient_version(void)
 		fprintf(stderr,
 			"emacsclient version '%d' too old (< 22).\n",
 			version);
-		strbuf_release(&buffer);
-		return -1;
-	}
-
+	} else
+		ret = 0;
+out:
 	strbuf_release(&buffer);
-	return 0;
+	return ret;
 }
 
 static void exec_woman_emacs(const char *path, const char *page)

diff --git a/tools/perf/perf.c b/tools/perf/perf.c
@@ -309,9 +309,11 @@ static int handle_alias(int *argcp, const char ***argv)
 			if (*argcp > 1) {
 				struct strbuf buf;
 
-				strbuf_init(&buf, PATH_MAX);
-				strbuf_addstr(&buf, alias_string);
-				sq_quote_argv(&buf, (*argv) + 1, PATH_MAX);
+				if (strbuf_init(&buf, PATH_MAX) < 0 ||
+				    strbuf_addstr(&buf, alias_string) < 0 ||
+				    sq_quote_argv(&buf, (*argv) + 1,
+						  PATH_MAX) < 0)
+					die("Failed to allocate memory.");
 				free(alias_string);
 				alias_string = buf.buf;
 			}

diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build
@@ -38,6 +38,7 @@ perf-y += cpumap.o
 perf-y += stat.o
 perf-y += event_update.o
 perf-y += event-times.o
+perf-y += backward-ring-buffer.o
 
 $(OUTPUT)tests/llvm-src-base.c: tests/bpf-script-example.c tests/Build
 	$(call rule_mkdir)

diff --git a/tools/perf/tests/backward-ring-buffer.c b/tools/perf/tests/backward-ring-buffer.c
@@ -0,0 +1,151 @@
+/*
+ * Test backward bit in event attribute, read ring buffer from end to
+ * beginning
+ */
+
+#include <perf.h>
+#include <evlist.h>
+#include <sys/prctl.h>
+#include "tests.h"
+#include "debug.h"
+
+#define NR_ITERS 111
+
+static void testcase(void)
+{
+	int i;
+
+	for (i = 0; i < NR_ITERS; i++) {
+		char proc_name[10];
+
+		snprintf(proc_name, sizeof(proc_name), "p:%d\n", i);
+		prctl(PR_SET_NAME, proc_name);
+	}
+}
+
+static int count_samples(struct perf_evlist *evlist, int *sample_count,
+			 int *comm_count)
+{
+	int i;
+
+	for (i = 0; i < evlist->nr_mmaps; i++) {
+		union perf_event *event;
+
+		perf_evlist__mmap_read_catchup(evlist, i);
+		while ((event = perf_evlist__mmap_read_backward(evlist, i)) != NULL) {
+			const u32 type = event->header.type;
+
+			switch (type) {
+			case PERF_RECORD_SAMPLE:
+				(*sample_count)++;
+				break;
+			case PERF_RECORD_COMM:
+				(*comm_count)++;
+				break;
+			default:
+				pr_err("Unexpected record of type %d\n", type);
+				return TEST_FAIL;
+			}
+		}
+	}
+	return TEST_OK;
+}
+
+static int do_test(struct perf_evlist *evlist, int mmap_pages,
+		   int *sample_count, int *comm_count)
+{
+	int err;
+	char sbuf[STRERR_BUFSIZE];
+
+	err = perf_evlist__mmap(evlist, mmap_pages, true);
+	if (err < 0) {
+		pr_debug("perf_evlist__mmap: %s\n",
+			 strerror_r(errno, sbuf, sizeof(sbuf)));
+		return TEST_FAIL;
+	}
+
+	perf_evlist__enable(evlist);
+	testcase();
+	perf_evlist__disable(evlist);
+
+	err = count_samples(evlist, sample_count, comm_count);
+	perf_evlist__munmap(evlist);
+	return err;
+}
+
+
+int test__backward_ring_buffer(int subtest __maybe_unused)
+{
+	int ret = TEST_SKIP, err, sample_count = 0, comm_count = 0;
+	char pid[16], sbuf[STRERR_BUFSIZE];
+	struct perf_evlist *evlist;
+	struct perf_evsel *evsel __maybe_unused;
+	struct parse_events_error parse_error;
+	struct record_opts opts = {
+		.target = {
+			.uid = UINT_MAX,
+			.uses_mmap = true,
+		},
+		.freq	      = 0,
+		.mmap_pages   = 256,
+		.default_interval = 1,
+	};
+
+	snprintf(pid, sizeof(pid), "%d", getpid());
+	pid[sizeof(pid) - 1] = '\0';
+	opts.target.tid = opts.target.pid = pid;
+
+	evlist = perf_evlist__new();
+	if (!evlist) {
+		pr_debug("No ehough memory to create evlist\n");
+		return TEST_FAIL;
+	}
+
+	err = perf_evlist__create_maps(evlist, &opts.target);
+	if (err < 0) {
+		pr_debug("Not enough memory to create thread/cpu maps\n");
+		goto out_delete_evlist;
+	}
+
+	bzero(&parse_error, sizeof(parse_error));
+	err = parse_events(evlist, "syscalls:sys_enter_prctl", &parse_error);
+	if (err) {
+		pr_debug("Failed to parse tracepoint event, try use root\n");
+		ret = TEST_SKIP;
+		goto out_delete_evlist;
+	}
+
+	perf_evlist__config(evlist, &opts, NULL);
+
+	/* Set backward bit, ring buffer should be writing from end */
+	evlist__for_each(evlist, evsel)
+		evsel->attr.write_backward = 1;
+
+	err = perf_evlist__open(evlist);
+	if (err < 0) {
+		pr_debug("perf_evlist__open: %s\n",
+			 strerror_r(errno, sbuf, sizeof(sbuf)));
+		goto out_delete_evlist;
+	}
+
+	ret = TEST_FAIL;
+	err = do_test(evlist, opts.mmap_pages, &sample_count,
+		      &comm_count);
+	if (err != TEST_OK)
+		goto out_delete_evlist;
+
+	if ((sample_count != NR_ITERS) || (comm_count != NR_ITERS)) {
+		pr_err("Unexpected counter: sample_count=%d, comm_count=%d\n",
+		       sample_count, comm_count);
+		goto out_delete_evlist;
+	}
+
+	err = do_test(evlist, 1, &sample_count, &comm_count);
+	if (err != TEST_OK)
+		goto out_delete_evlist;
+
+	ret = TEST_OK;
+out_delete_evlist:
+	perf_evlist__delete(evlist);
+	return ret;
+}
diff --git a/tools/perf/tests/builtin-test.c b/tools/perf/tests/builtin-test.c
@@ -207,6 +207,10 @@ static struct test generic_tests[] = {
 		.desc = "Test events times",
 		.func = test__event_times,
 	},
+	{
+		.desc = "Test backward reading from ring buffer",
+		.func = test__backward_ring_buffer,
+	},
 	{
 		.func = NULL,
 	},

diff --git a/tools/perf/tests/tests.h b/tools/perf/tests/tests.h
@@ -86,6 +86,7 @@ int test__synthesize_stat(int subtest);
 int test__synthesize_stat_round(int subtest);
 int test__event_update(int subtest);
 int test__event_times(int subtest);
+int test__backward_ring_buffer(int subtest);
 
 #if defined(__arm__) || defined(__aarch64__)
 #ifdef HAVE_DWARF_UNWIND_SUPPORT

diff --git a/tools/perf/util/Build b/tools/perf/util/Build
@@ -27,7 +27,6 @@ libperf-y += strlist.o
 libperf-y += strfilter.o
 libperf-y += top.o
 libperf-y += usage.o
-libperf-y += wrapper.o
 libperf-y += dso.o
 libperf-y += symbol.o
 libperf-y += symbol_fprintf.o

diff --git a/tools/perf/util/cache.h b/tools/perf/util/cache.h
@@ -40,25 +40,6 @@ int split_cmdline(char *cmdline, const char ***argv);
 
 #define alloc_nr(x) (((x)+16)*3/2)
 
-/*
- * Realloc the buffer pointed at by variable 'x' so that it can hold
- * at least 'nr' entries; the number of entries currently allocated
- * is 'alloc', using the standard growing factor alloc_nr() macro.
- *
- * DO NOT USE any expression with side-effect for 'x' or 'alloc'.
- */
-#define ALLOC_GROW(x, nr, alloc) \
-	do { \
-		if ((nr) > alloc) { \
-			if (alloc_nr(alloc) < (nr)) \
-				alloc = (nr); \
-			else \
-				alloc = alloc_nr(alloc); \
-			x = xrealloc((x), alloc * sizeof(*(x))); \
-		} \
-	} while(0)
-
-
 static inline int is_absolute_path(const char *path)
 {
 	return path[0] == '/';

diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
@@ -915,8 +915,7 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		tmp = "*";
 	else if (tag == DW_TAG_subroutine_type) {
 		/* Function pointer */
-		strbuf_add(buf, "(function_type)", 15);
-		return 0;
+		return strbuf_add(buf, "(function_type)", 15);
 	} else {
 		if (!dwarf_diename(&type))
 			return -ENOENT;
@@ -927,14 +926,10 @@ int die_get_typename(Dwarf_Die *vr_die, struct strbuf *buf)
 		else if (tag == DW_TAG_enumeration_type)
 			tmp = "enum ";
 		/* Write a base name */
-		strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
-		return 0;
+		return strbuf_addf(buf, "%s%s", tmp, dwarf_diename(&type));
 	}
 	ret = die_get_typename(&type, buf);
-	if (ret == 0)
-		strbuf_addstr(buf, tmp);
-
-	return ret;
+	return ret ? ret : strbuf_addstr(buf, tmp);
 }
 
 /**
@@ -951,12 +946,10 @@ int die_get_varname(Dwarf_Die *vr_die, struct strbuf *buf)
 	ret = die_get_typename(vr_die, buf);
 	if (ret < 0) {
 		pr_debug("Failed to get type, make it unknown.\n");
-		strbuf_add(buf, " (unknown_type)", 14);
+		ret = strbuf_add(buf, " (unknown_type)", 14);
 	}
 
-	strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
-
-	return 0;
+	return ret < 0 ? ret : strbuf_addf(buf, "\t%s", dwarf_diename(vr_die));
 }
 
 #ifdef HAVE_DWARF_GETLOCATIONS
@@ -999,22 +992,24 @@ static int die_get_var_innermost_scope(Dwarf_Die *sp_die, Dwarf_Die *vr_die,
 	}
 
 	while ((offset = dwarf_ranges(&scopes[1], offset, &base,
-				&start, &end)) > 0) {
+					&start, &end)) > 0) {
 		start -= entry;
 		end -= entry;
 
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
+		if (ret < 0)
+			goto out;
 	}
 
 	if (!first)
-		strbuf_add(buf, "]>", 2);
+		ret = strbuf_add(buf, "]>", 2);
 
 out:
 	free(scopes);
@@ -1054,31 +1049,32 @@ int die_get_var_range(Dwarf_Die *sp_die, Dwarf_Die *vr_die, struct strbuf *buf)
 	if (dwarf_attr(vr_die, DW_AT_location, &attr) == NULL)
 		return -EINVAL;
 
-	while ((offset = dwarf_getlocations(
-				&attr, offset, &base,
-				&start, &end, &op, &nops)) > 0) {
+	while ((offset = dwarf_getlocations(&attr, offset, &base,
+					&start, &end, &op, &nops)) > 0) {
 		if (start == 0) {
 			/* Single Location Descriptions */
 			ret = die_get_var_innermost_scope(sp_die, vr_die, buf);
-			return ret;
+			goto out;
 		}
 
 		/* Location Lists */
 		start -= entry;
 		end -= entry;
 		if (first) {
-			strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
-				name, start, end);
+			ret = strbuf_addf(buf, "@<%s+[%" PRIu64 "-%" PRIu64,
+					  name, start, end);
 			first = false;
 		} else {
-			strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
-				start, end);
+			ret = strbuf_addf(buf, ",%" PRIu64 "-%" PRIu64,
+					  start, end);
 		}
+		if (ret < 0)
+			goto out;
 	}
 
 	if (!first)
-		strbuf_add(buf, "]>", 2);
-
+		ret = strbuf_add(buf, "]>", 2);
+out:
 	return ret;
 }
 #else