Merge tag 'perf-tools-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux

Pull perf tooling updates from Arnaldo Carvalho de Melo:
 "These are additional changes to the perf tools, on top of what Ingo
  already submitted.

   - Further Intel PT call-trace fixes

   - Improve SELinux docs and tool warnings

   - Fix race at exit in 'perf record' using eventfd.

   - Add missing build tests to the default set of 'make -C tools/perf
     build-test'

   - Sync msr-index.h getting new AMD MSRs to decode and filter in 'perf
     trace'.

   - Fix fallback to libaudit in 'perf trace' for arches not using
     per-arch *.tbl files.

   - Fixes for 'perf ftrace'.

   - Fixes and improvements for the 'perf stat' metrics.

   - Use dummy event to get PERF_RECORD_{FORK,MMAP,etc} while
     synthesizing those metadata events for pre-existing threads.

   - Fix leaks detected using clang tooling.

   - Improvements to PMU event metric testing.

   - Report summary for 'perf stat' interval mode at the end, summing up
     all the intervals.

   - Improve pipe mode, i.e. this now works as expected, continuously
     dumping samples:

        # perf record -g -e raw_syscalls:sys_enter | perf --no-pager script

   - Fixes for event grouping, detecting incompatible groups such as:

        # perf stat -e '{cycles,power/energy-cores/}' -v
        WARNING: group events cpu maps do not match, disabling group:
          anon group { power/energy-cores/, cycles }
            power/energy-cores/: 0
            cycles: 0-7

   - Fixes for 'perf probe': blacklist address checking, number of
     kretprobe instances, etc.

   - JIT processing improvements and fixes plus the addition of a 'perf
     test' entry for the java demangler.

   - Add support for synthesizing first/last level cache, TLB and remove
     access events from HW tracing in the auxtrace code, first to use is
     ARM SPE.

   - Vendor events updates and fixes, including for POWER9 and Intel.

   - Allow using ~/.perfconfig for removing the ',' separators in 'perf
     stat' output.

   - Opt-in support for libpfm4"

* tag 'perf-tools-2020-06-02' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (120 commits)
  perf tools: Remove some duplicated includes
  perf symbols: Fix kernel maps for kcore and eBPF
  tools arch x86: Sync the msr-index.h copy with the kernel sources
  perf stat: Ensure group is defined on top of the same cpu mask
  perf libdw: Fix off-by 1 relative directory includes
  perf arm-spe: Support synthetic events
  perf auxtrace: Add four itrace options
  perf tools: Move arm-spe-pkt-decoder.h/c to the new dir
  perf test: Initialize memory in dwarf-unwind
  perf tests: Don't tail call optimize in unwind test
  tools compiler.h: Add attribute to disable tail calls
  perf build: Add a LIBPFM4=1 build test entry
  perf tools: Add optional support for libpfm4
  perf tools: Correct license on jsmn JSON parser
  perf jit: Fix inaccurate DWARF line table
  perf jvmti: Remove redundant jitdump line table entries
  perf build: Add NO_SDT=1 to the default set of build tests
  perf build: Add NO_LIBCRYPTO=1 to the default set of build tests
  perf build: Add NO_SYSCALL_TABLE=1 to the build tests
  perf build: Remove libaudit from the default feature checks
  ...

1 files changed, 26 insertions, 8 deletions

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 0ce47283a8a1..7a67d017d72c 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3574,7 +3574,7 @@ static int perf_header__read_pipe(struct perf_session *session)
 		return -EINVAL;
 	}
 
-	return 0;
+	return f_header.size == sizeof(f_header) ? 0 : -1;
 }
 
 static int read_attr(int fd, struct perf_header *ph,
@@ -3676,7 +3676,7 @@ int perf_session__read_header(struct perf_session *session)
 	struct perf_file_header	f_header;
 	struct perf_file_attr	f_attr;
 	u64			f_id;
-	int nr_attrs, nr_ids, i, j;
+	int nr_attrs, nr_ids, i, j, err;
 	int fd = perf_data__fd(data);
 
 	session->evlist = evlist__new();
@@ -3685,8 +3685,16 @@ int perf_session__read_header(struct perf_session *session)
 
 	session->evlist->env = &header->env;
 	session->machines.host.env = &header->env;
-	if (perf_data__is_pipe(data))
-		return perf_header__read_pipe(session);
+
+	/*
+	 * We can read 'pipe' data event from regular file,
+	 * check for the pipe header regardless of source.
+	 */
+	err = perf_header__read_pipe(session);
+	if (!err || (err && perf_data__is_pipe(data))) {
+		data->is_pipe = true;
+		return err;
+	}
 
 	if (perf_file_header__read(&f_header, header, fd) < 0)
 		return -EINVAL;
@@ -3947,12 +3955,22 @@ int perf_event__process_tracing_data(struct perf_session *session,
 {
 	ssize_t size_read, padding, size = event->tracing_data.size;
 	int fd = perf_data__fd(session->data);
-	off_t offset = lseek(fd, 0, SEEK_CUR);
 	char buf[BUFSIZ];
 
-	/* setup for reading amidst mmap */
-	lseek(fd, offset + sizeof(struct perf_record_header_tracing_data),
-	      SEEK_SET);
+	/*
+	 * The pipe fd is already in proper place and in any case
+	 * we can't move it, and we'd screw the case where we read
+	 * 'pipe' data from regular file. The trace_report reads
+	 * data from 'fd' so we need to set it directly behind the
+	 * event, where the tracing data starts.
+	 */
+	if (!perf_data__is_pipe(session->data)) {
+		off_t offset = lseek(fd, 0, SEEK_CUR);
+
+		/* setup for reading amidst mmap */
+		lseek(fd, offset + sizeof(struct perf_record_header_tracing_data),
+		      SEEK_SET);
+	}
 
 	size_read = trace_report(fd, &session->tevent,
 				 session->repipe);