Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf updates from Ingo Molnar:
 "This update is pretty big and almost exclusively includes tooling
  changes, because v4.9's LTS status forced to completion most of the
  pending kernel side hardware enablement work and because we tried to
  freeze core perf work a bit to give a time window for the fuzzing
  efforts.

  The diff is large mostly due to the JSON hardware event tables added
  for Intel and Power8 CPUs. This was a popular feature request from
  people working close to hardware and from the HPC community.

  Tree size is big because this added the CPU event tables for over a
  decade of Intel CPUs. Future changes for a CPU vendor alrady support
  should be much smaller, as events for new models are added. The new
  events are listed in 'perf list', for the CPU model the tool is
  running on. If you find an interesting event it can be used as-is:

      $ perf stat -a -e l2_lines_out.pf_clean sleep 1

      Performance counter stats for 'system wide':

            7,860,403      l2_lines_out.pf_clean

           1.000624918 seconds time elapsed

  The event lists can be searched the usual 'perf list' fashion for
  (case insensitive) substrings as well:

      $ perf list l2_lines_out

      List of pre-defined events (to be used in -e):

      cache:
        l2_lines_out.demand_clean
             [Clean L2 cache lines evicted by demand]
        l2_lines_out.demand_dirty
             [Dirty L2 cache lines evicted by demand]
        l2_lines_out.dirty_all
             [Dirty L2 cache lines filling the L2]
        l2_lines_out.pf_clean
             [Clean L2 cache lines evicted by L2 prefetch]
        l2_lines_out.pf_dirty
             [Dirty L2 cache lines evicted by L2 prefetch]

  etc.

  There's a few high level categories as well that can be listed:
  'cache', 'floating point', 'frontend', 'memory', 'pipeline', 'virtual
  memory'.

  Existing generic events and workflows should work as-is.

  The only kernel side change is a late breaking fix for an older
  regression, related to Intel BTS, LBR and PT feature interaction.

  On the tooling side there are three new tools / major features:

   - The new 'perf c2c' tool provides means for Shared Data C2C/HITM
     analysis.

     This allows you to track down cacheline contention. The tool is
     based on x86's load latency and precise store facility events
     provided by Intel CPUs.

     It was tested by Joe Mario and has proven to be useful, finding
     some cacheline contentions. Joe also wrote a blog about c2c tool
     with examples:

        https://joemario.github.io/blog/2016/09/01/c2c-blog/

     excerpt of the content on this site:

         At a high level, “perf c2c” will show you:

          * The cachelines where false sharing was detected.
          * The readers and writers to those cachelines, and the offsets where those accesses occurred.
          * The pid, tid, instruction addr, function name, binary object name for those readers and writers.
          * The source file and line number for each reader and writer.
          * The average load latency for the loads to those cachelines.
          * Which numa nodes the samples a cacheline came from and which CPUs were involved.

         Using perf c2c is similar to using the Linux perf tool today.
         First collect data with “perf c2c record”, then generate a
         report output with “perf c2c report”

     There one finds extensive details on using the tool, with tips on
     reducing the volume of samples while still capturing enough to do
     its job. (Dick Fowles, Joe Mario, Don Zickus, Jiri Olsa)

   - The new 'perf sched timehist' tool provides tailored analysis of
     scheduling events.

     Example usage:

          perf sched record -- sleep 1
          perf sched timehist

     By default it shows the individual schedule events, including the
     wait time (time between sched-out and next sched-in events for the
     task), the task scheduling delay (time between wakeup and actually
     running) and run time for the task:

            time    cpu  task name         wait time  sch delay  run time
                         [tid/pid]            (msec)     (msec)    (msec)
        -------- ------  ----------------  ---------  ---------  --------
        1.874569 [0011]  gcc[31949]            0.014      0.000     1.148
        1.874591 [0010]  gcc[31951]            0.000      0.000     0.024
        1.874603 [0010]  migration/10[59]      3.350      0.004     0.011
        1.874604 [0011]  <idle>                1.148      0.000     0.035
        1.874723 [0005]  <idle>                0.016      0.000     1.383
        1.874746 [0005]  gcc[31949]            0.153      0.078     0.022
      ...

     Times are in msec.usec. (David Ahern, Namhyung Kim)

   - Add CPU vendor hardware event tables:

     Add JSON files with vendor event naming for Intel and Power8
     processors, allowing users of tools like oprofile to keep using the
     event names they are used to, as well as people reading vendor
     documentation, where such naming is used. (Andi Kleen, Sukadev
     Bhattiprolu)

     You should see all the new events with 'perf list' and you should
     be able to search them, for example 'perf list miss' will list all
     the myriads of miss events.

  Other tooling features added were:

   - Cross-arch annotation support:

     o Improve ARM support in the annotation code, affecting 'perf
       annotate', 'perf report' and live annotation in 'perf top' (Kim
       Phillips)

     o Initial support for PowerPC in the annotation code (Ravi
       Bangoria)

     o Support AArch64 in the 'annotate' code, native/local and
       cross-arch/remote (Kim Phillips)

   - Allow considering just events in a given time interval, via the
     '--time start.s.ms,end.s.ms' command line, added to 'perf kmem',
     'perf report', 'perf sched timehist' and 'perf script' (David
     Ahern)

   - Add option to stop printing a callchain at one of a given group of
     symbol names (David Ahern)

   - Track memory freed in 'perf kmem stat' (David Ahern)

   - Allow querying and setting .perfconfig variables (Taeung Song)

   - Show branch information in callchains (predicted, TSX aborts, loop
     iteractions, etc) (Jin Yao)

   - Dynamicly change verbosity level by pressing 'V' in the 'perf
     top/report' hists TUI browser (Alexis Berlemont)

   - Implement 'perf trace --delay' in the same fashion as in 'perf
     record --delay', to skip sampling workload initialization events
     (Alexis Berlemont)

   - Make vendor named events case insensitive in 'perf list', i.e.
     'perf list LONGEST_LAT' works just the same as 'perf list
     longest_lat' (Andi Kleen)

   - Add unwinding support for jitdump (Stefano Sanfilippo)

  Tooling infrastructure changes:

   - Support linking perf with clang and LLVM libraries, initially
     statically, but this limitation will be lifted and shared
     libraries, when available, will be preferred to the static build,
     that should, as with other features, be enabled explicitly (Wang
     Nan)

   - Add initial support (and perf test entry) for tooling hooks,
     starting with 'record_start' and 'record_end', that will have as
     its initial user the eBPF infrastructure, where perf_ prefixed
     functions will be JITed and run when such hooks are called (Wang
     Nan)

   - Implement assorted libbpf improvements (Wang Nan)"

  ... and lots of other changes, features, cleanups and refactorings I
  did not list, see the shortlog and the git log for details"

* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (220 commits)
  perf/x86: Fix exclusion of BTS and LBR for Goldmont
  perf tools: Explicitly document that --children is enabled by default
  perf sched timehist: Cleanup idle_max_cpu handling
  perf sched timehist: Handle zero sample->tid properly
  perf callchain: Introduce callchain_cursor__copy()
  perf sched: Cleanup option processing
  perf sched timehist: Improve error message when analyzing wrong file
  perf tools: Move perf build related variables under non fixdep leg
  perf tools: Force fixdep compilation at the start of the build
  perf tools: Move PERF-VERSION-FILE target into rules area
  perf build: Check LLVM version in feature check
  perf annotate: Show raw form for jump instruction with indirect target
  perf tools: Add non config targets
  perf tools: Cleanup build directory before each test
  perf tools: Move python/perf.so target into rules area
  perf tools: Move install-gtk target into rules area
  tools build: Move tabs to spaces where suitable
  tools build: Make the .cmd file more readable
  perf clang: Compile BPF script using builtin clang support
  perf clang: Support compile IR to BPF object and add testcase
  ...

2 files changed, 7 insertions, 3 deletions

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 6e395c996900..7fe88bb57e36 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -365,7 +365,11 @@ int x86_add_exclusive(unsigned int what)
 {
 	int i;
 
-	if (x86_pmu.lbr_pt_coexist)
+	/*
+	 * When lbr_pt_coexist we allow PT to coexist with either LBR or BTS.
+	 * LBR and BTS are still mutually exclusive.
+	 */
+	if (x86_pmu.lbr_pt_coexist && what == x86_lbr_exclusive_pt)
 		return 0;
 
 	if (!atomic_inc_not_zero(&x86_pmu.lbr_exclusive[what])) {
@@ -388,7 +392,7 @@ fail_unlock:
 
 void x86_del_exclusive(unsigned int what)
 {
-	if (x86_pmu.lbr_pt_coexist)
+	if (x86_pmu.lbr_pt_coexist && what == x86_lbr_exclusive_pt)
 		return;
 
 	atomic_dec(&x86_pmu.lbr_exclusive[what]);
diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h
index a77ee026643d..bcbb1d2ae10b 100644
--- a/arch/x86/events/perf_event.h
+++ b/arch/x86/events/perf_event.h
@@ -604,7 +604,7 @@ struct x86_pmu {
 	u64		lbr_sel_mask;		   /* LBR_SELECT valid bits */
 	const int	*lbr_sel_map;		   /* lbr_select mappings */
 	bool		lbr_double_abort;	   /* duplicated lbr aborts */
-	bool		lbr_pt_coexist;		   /* LBR may coexist with PT */
+	bool		lbr_pt_coexist;		   /* (LBR|BTS) may coexist with PT */
 
 	/*
 	 * Intel PT/LBR/BTS are exclusive