Merge tag 'perf-tools-for-v5.14-2021-07-10' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull more perf tool updates from Arnaldo Carvalho de Melo:
 "New features:

   - Enable use of BPF counters with 'perf stat --for-each-cgroup',
     using per-CPU 'cgroup-switch' events with an attached BPF program
     that does aggregation per-cgroup in the kernel instead of using
     per-cgroup perf events.

   - Add Topdown metrics L2 events as default events in 'perf stat' for
     systems having those events.

  Hardware tracing:

   - Add a config for max loops without consuming a packet in the Intel
     PT packet decoder, set via 'perf config intel-pt.max-loops=N'

  Hardware enablement:

   - Disable misleading NMI watchdog message in 'perf stat' on hybrid
     systems such as Intel Alder Lake.

   - Add a dummy event on hybrid systems to collect metadata records.

   - Add 24x7 nest metric events for the Power10 platform.

  Fixes:

   - Fix event parsing for PMUs starting with the same prefix.

   - Fix the 'perf trace' 'trace' alias installation dir.

   - Fix buffer size to report iregs in perf script python scripts,
     supporting the extended registers in PowerPC.

   - Fix overflow in elf_sec__is_text().

   - Fix 's' on source line when disasm is empty in the annotation TUI,
     accessible via 'perf annotate', 'perf report' and 'perf top'.

   - Plug leaks in scandir() returned dirent entries in 'perf test' when
     sorting the shell tests.

   - Fix --task and --stat with pipe input in 'perf report'.

   - Fix 'perf probe' use of debuginfo files by build id.

   - If a DSO has both dynsym and symtab ELF sections, read from both
     when loading the symbol table, fixing a problem processing Fedora
     32 glibc DSOs.

  Libraries:

   - Add grouping of events to libperf, from code in tools/perf,
     allowing libperf users to use that mode.

  Misc:

   - Filter plt stubs from the 'perf probe --functions' output.

   - Update UAPI header copies for asound, DRM, mman-common.h and the
     ones affected by the quotactl_fd syscall"

* tag 'perf-tools-for-v5.14-2021-07-10' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (29 commits)
  perf test: Add free() calls for scandir() returned dirent entries
  libperf: Add tests for perf_evlist__set_leader()
  libperf: Remove BUG_ON() from library code in get_group_fd()
  libperf: Add group support to perf_evsel__open()
  perf tools: Fix pattern matching for same substring in different PMU type
  perf record: Add a dummy event on hybrid systems to collect metadata records
  perf stat: Add Topdown metrics L2 events as default events
  libperf: Adopt evlist__set_leader() from tools/perf as perf_evlist__set_leader()
  libperf: Move 'nr_groups' from tools/perf to evlist::nr_groups
  libperf: Move 'leader' from tools/perf to perf_evsel::leader
  libperf: Move 'idx' from tools/perf to perf_evsel::idx
  libperf: Change tests to single static and shared binaries
  perf intel-pt: Add a config for max loops without consuming a packet
  perf stat: Disable the NMI watchdog message on hybrid
  perf vendor events power10: Adds 24x7 nest metric events for power10 platform
  perf script python: Fix buffer size to report iregs in perf script
  perf trace: Fix the perf trace link location
  perf top: Fix overflow in elf_sec__is_text()
  perf annotate: Fix 's' on source line when disasm is empty
  perf probe: Do not show @plt function by default
  ...

1 files changed, 12 insertions, 5 deletions

diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index 164d2f45028c..69129e2aa7a1 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -687,7 +687,7 @@ static void set_sample_datasrc_in_dict(PyObject *dict,
 			_PyUnicode_FromString(decode));
 }
 
-static int regs_map(struct regs_dump *regs, uint64_t mask, char *bf, int size)
+static void regs_map(struct regs_dump *regs, uint64_t mask, char *bf, int size)
 {
 	unsigned int i = 0, r;
 	int printed = 0;
@@ -695,7 +695,7 @@ static int regs_map(struct regs_dump *regs, uint64_t mask, char *bf, int size)
 	bf[0] = 0;
 
 	if (!regs || !regs->regs)
-		return 0;
+		return;
 
 	for_each_set_bit(r, (unsigned long *) &mask, sizeof(mask) * 8) {
 		u64 val = regs->regs[i++];
@@ -704,8 +704,6 @@ static int regs_map(struct regs_dump *regs, uint64_t mask, char *bf, int size)
 				     "%5s:0x%" PRIx64 " ",
 				     perf_reg_name(r), val);
 	}
-
-	return printed;
 }
 
 static void set_regs_in_dict(PyObject *dict,
@@ -713,7 +711,16 @@ static void set_regs_in_dict(PyObject *dict,
 			     struct evsel *evsel)
 {
 	struct perf_event_attr *attr = &evsel->core.attr;
-	char bf[512];
+
+	/*
+	 * Here value 28 is a constant size which can be used to print
+	 * one register value and its corresponds to:
+	 * 16 chars is to specify 64 bit register in hexadecimal.
+	 * 2 chars is for appending "0x" to the hexadecimal value and
+	 * 10 chars is for register name.
+	 */
+	int size = __sw_hweight64(attr->sample_regs_intr) * 28;
+	char bf[size];
 
 	regs_map(&sample->intr_regs, attr->sample_regs_intr, bf, sizeof(bf));