perf/urgent fixes:

perf.data:
 
   Alexey Budankov:
 
   - Fix loading of compressed data split across adjacent records
 
   Jiri Olsa:
 
   - Fix buffer size setting for processing CPU topology perf.data header.
 
 perf stat:
 
   Jiri Olsa:
 
   - Fix segfault for event group in repeat mode
 
   Cong Wang:
 
   - Always separate "stalled cycles per insn" line, it was being appended to
     the "instructions" line.
 
 perf script:
 
   Andi Kleen:
 
   - Fix --max-blocks man page description.
 
   - Improve man page description of metrics.
 
   - Fix off by one in brstackinsn IPC computation.
 
 perf probe:
 
   Arnaldo Carvalho de Melo:
 
   - Avoid calling freeing routine multiple times for same pointer.
 
 perf build:
 
   - Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
     treated as errors, breaking the build.
 
 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-5.3-20190723' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent

Pull perf/urgent fixes from Arnaldo Carvalho de Melo:

perf.data:

  Alexey Budankov:

  - Fix loading of compressed data split across adjacent records

  Jiri Olsa:

  - Fix buffer size setting for processing CPU topology perf.data header.

perf stat:

  Jiri Olsa:

  - Fix segfault for event group in repeat mode

  Cong Wang:

  - Always separate "stalled cycles per insn" line, it was being appended to
    the "instructions" line.

perf script:

  Andi Kleen:

  - Fix --max-blocks man page description.

  - Improve man page description of metrics.

  - Fix off by one in brstackinsn IPC computation.

perf probe:

  Arnaldo Carvalho de Melo:

  - Avoid calling freeing routine multiple times for same pointer.

perf build:

  - Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
    treated as errors, breaking the build.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

tools/perf/Documentation/perf-script.txt

@@ -228,11 +228,11 @@ OPTIONS
 
 	With the metric option perf script can compute metrics for
 	sampling periods, similar to perf stat. This requires
-	specifying a group with multiple metrics with the :S option
+	specifying a group with multiple events defining metrics with the :S option
 	for perf record. perf will sample on the first event, and
-	compute metrics for all the events in the group. Please note
+	print computed metrics for all the events in the group. Please note
 	that the metric computed is averaged over the whole sampling
-	period, not just for the sample point.
+	period (since the last sample), not just for the sample point.
 
 	For sample events it's possible to display misc field with -F +misc option,
 	following letters are displayed for each bit:
@@ -384,7 +384,7 @@ include::itrace.txt[]
 	perf script --time 0%-10%,30%-40%
 
 --max-blocks::
-	Set the maximum number of program blocks to print with brstackasm for
+	Set the maximum number of program blocks to print with brstackinsn for
 	each sample.
 
 --reltime::

tools/perf/builtin-probe.c

@@ -698,6 +698,16 @@ __cmd_probe(int argc, const char **argv)
 
 		ret = perf_add_probe_events(params.events, params.nevents);
 		if (ret < 0) {
+
+			/*
+			 * When perf_add_probe_events() fails it calls
+			 * cleanup_perf_probe_events(pevs, npevs), i.e.
+			 * cleanup_perf_probe_events(params.events, params.nevents), which
+			 * will call clear_perf_probe_event(), so set nevents to zero
+			 * to avoid cleanup_params() to call clear_perf_probe_event() again
+			 * on the same pevs.
+			 */
+			params.nevents = 0;
 			pr_err_with_code("  Error: Failed to add events.", ret);
 			return ret;
 		}

tools/perf/builtin-script.c

@@ -1059,7 +1059,7 @@ static int perf_sample__fprintf_brstackinsn(struct perf_sample *sample,
 
 			printed += ip__fprintf_sym(ip, thread, x.cpumode, x.cpu, &lastsym, attr, fp);
 			if (ip == end) {
-				printed += ip__fprintf_jump(ip, &br->entries[i], &x, buffer + off, len - off, insn, fp,
+				printed += ip__fprintf_jump(ip, &br->entries[i], &x, buffer + off, len - off, ++insn, fp,
 							    &total_cycles);
 				if (PRINT_FIELD(SRCCODE))
 					printed += print_srccode(thread, x.cpumode, ip);

tools/perf/builtin-stat.c

@@ -607,7 +607,13 @@ try_again:
 	 * group leaders.
 	 */
 	read_counters(&(struct timespec) { .tv_nsec = t1-t0 });
-	perf_evlist__close(evsel_list);
+
+	/*
+	 * We need to keep evsel_list alive, because it's processed
+	 * later the evsel_list will be closed after.
+	 */
+	if (!STAT_RECORD)
+		perf_evlist__close(evsel_list);
 
 	return WEXITSTATUS(status);
 }
@@ -1997,6 +2003,7 @@ int cmd_stat(int argc, const char **argv)
 			perf_session__write_header(perf_stat.session, evsel_list, fd, true);
 		}
 
+		perf_evlist__close(evsel_list);
 		perf_session__delete(perf_stat.session);
 	}
 

tools/perf/util/evsel.c

@@ -1291,6 +1291,7 @@ static void perf_evsel__free_id(struct perf_evsel *evsel)
 	xyarray__delete(evsel->sample_id);
 	evsel->sample_id = NULL;
 	zfree(&evsel->id);
+	evsel->ids = 0;
 }
 
 static void perf_evsel__free_config_terms(struct perf_evsel *evsel)
@@ -2077,6 +2078,7 @@ void perf_evsel__close(struct perf_evsel *evsel)
 
 	perf_evsel__close_fd(evsel);
 	perf_evsel__free_fd(evsel);
+	perf_evsel__free_id(evsel);
 }
 
 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,

tools/perf/util/header.c

@@ -3747,7 +3747,7 @@ int perf_event__process_feature(struct perf_session *session,
 		return 0;
 
 	ff.buf  = (void *)fe->data;
-	ff.size = event->header.size - sizeof(event->header);
+	ff.size = event->header.size - sizeof(*fe);
 	ff.ph = &session->header;
 
 	if (feat_ops[feat].process(&ff, NULL))

tools/perf/util/probe-event.c

@@ -2230,6 +2230,7 @@ void clear_perf_probe_event(struct perf_probe_event *pev)
 			field = next;
 		}
 	}
+	pev->nargs = 0;
 	zfree(&pev->args);
 }
 

tools/perf/util/session.c

@@ -36,10 +36,16 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	void *src;
 	size_t decomp_size, src_size;
 	u64 decomp_last_rem = 0;
-	size_t decomp_len = session->header.env.comp_mmap_len;
+	size_t mmap_len, decomp_len = session->header.env.comp_mmap_len;
 	struct decomp *decomp, *decomp_last = session->decomp_last;
 
-	decomp = mmap(NULL, sizeof(struct decomp) + decomp_len, PROT_READ|PROT_WRITE,
+	if (decomp_last) {
+		decomp_last_rem = decomp_last->size - decomp_last->head;
+		decomp_len += decomp_last_rem;
+	}
+
+	mmap_len = sizeof(struct decomp) + decomp_len;
+	decomp = mmap(NULL, mmap_len, PROT_READ|PROT_WRITE,
 		      MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
 	if (decomp == MAP_FAILED) {
 		pr_err("Couldn't allocate memory for decompression\n");
@@ -47,10 +53,10 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	}
 
 	decomp->file_pos = file_offset;
+	decomp->mmap_len = mmap_len;
 	decomp->head = 0;
 
-	if (decomp_last) {
-		decomp_last_rem = decomp_last->size - decomp_last->head;
+	if (decomp_last_rem) {
 		memcpy(decomp->data, &(decomp_last->data[decomp_last->head]), decomp_last_rem);
 		decomp->size = decomp_last_rem;
 	}
@@ -61,7 +67,7 @@ static int perf_session__process_compressed_event(struct perf_session *session,
 	decomp_size = zstd_decompress_stream(&(session->zstd_data), src, src_size,
 				&(decomp->data[decomp_last_rem]), decomp_len - decomp_last_rem);
 	if (!decomp_size) {
-		munmap(decomp, sizeof(struct decomp) + decomp_len);
+		munmap(decomp, mmap_len);
 		pr_err("Couldn't decompress data\n");
 		return -1;
 	}
@@ -255,15 +261,15 @@ static void perf_session__delete_threads(struct perf_session *session)
 static void perf_session__release_decomp_events(struct perf_session *session)
 {
 	struct decomp *next, *decomp;
-	size_t decomp_len;
+	size_t mmap_len;
 	next = session->decomp;
-	decomp_len = session->header.env.comp_mmap_len;
 	do {
 		decomp = next;
 		if (decomp == NULL)
 			break;
 		next = decomp->next;
-		munmap(decomp, decomp_len + sizeof(struct decomp));
+		mmap_len = decomp->mmap_len;
+		munmap(decomp, mmap_len);
 	} while (1);
 }
 

tools/perf/util/session.h

@@ -46,6 +46,7 @@ struct perf_session {
 struct decomp {
 	struct decomp *next;
 	u64 file_pos;
+	size_t mmap_len;
 	u64 head;
 	size_t size;
 	char data[];

tools/perf/util/stat-shadow.c

@@ -819,7 +819,8 @@ void perf_stat__print_shadow_stats(struct perf_stat_config *config,
 					"stalled cycles per insn",
 					ratio);
 		} else if (have_frontend_stalled) {
-			print_metric(config, ctxp, NULL, NULL,
+			out->new_line(config, ctxp);
+			print_metric(config, ctxp, NULL, "%7.2f ",
 				     "stalled cycles per insn", 0);
 		}
 	} else if (perf_evsel__match(evsel, HARDWARE, HW_BRANCH_MISSES)) {

tools/perf/util/zstd.c

@@ -99,8 +99,8 @@ size_t zstd_decompress_stream(struct zstd_data *data, void *src, size_t src_size
 	while (input.pos < input.size) {
 		ret = ZSTD_decompressStream(data->dstream, &output, &input);
 		if (ZSTD_isError(ret)) {
-			pr_err("failed to decompress (B): %ld -> %ld : %s\n",
-			       src_size, output.size, ZSTD_getErrorName(ret));
+			pr_err("failed to decompress (B): %ld -> %ld, dst_size %ld : %s\n",
+			       src_size, output.size, dst_size, ZSTD_getErrorName(ret));
 			break;
 		}
 		output.dst  = dst + output.pos;

tools/scripts/Makefile.include

@@ -32,7 +32,6 @@ EXTRA_WARNINGS += -Wno-system-headers
 EXTRA_WARNINGS += -Wold-style-definition
 EXTRA_WARNINGS += -Wpacked
 EXTRA_WARNINGS += -Wredundant-decls
-EXTRA_WARNINGS += -Wshadow
 EXTRA_WARNINGS += -Wstrict-prototypes
 EXTRA_WARNINGS += -Wswitch-default
 EXTRA_WARNINGS += -Wswitch-enum
@@ -69,8 +68,16 @@ endif
 # will do for now and keep the above -Wstrict-aliasing=3 in place
 # in newer systems.
 # Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h
+#
+# See https://lkml.org/lkml/2006/11/28/253 and https://gcc.gnu.org/gcc-4.8/changes.html,
+# that takes into account Linus's comments (search for Wshadow) for the reasoning about
+# -Wshadow not being interesting before gcc 4.8.
+
 ifneq ($(filter 3.%,$(MAKE_VERSION)),)  # make-3
 EXTRA_WARNINGS += -fno-strict-aliasing
+EXTRA_WARNINGS += -Wno-shadow
+else
+EXTRA_WARNINGS += -Wshadow
 endif
 
 ifneq ($(findstring $(MAKEFLAGS), w),w)