linux-toradex.git/tools/perf/builtin-top.c, branch v5.3-rc3

perf top: Fix potential NULL pointer dereference detected by the smatch tool

2019-07-09T12:33:54+00:00

Based on the following report from Smatch, fix the potential NULL
pointer dereference check.

  tools/perf/builtin-top.c:109
  perf_top__parse_source() warn: variable dereferenced before check 'he'
  (see line 103)

  tools/perf/builtin-top.c:233
  perf_top__show_details() warn: variable dereferenced before check 'he'
  (see line 228)

  tools/perf/builtin-top.c
  101 static int perf_top__parse_source(struct perf_top *top, struct hist_entry *he)
  102 {
  103         struct perf_evsel *evsel = hists_to_evsel(he->hists);
                                                        ^^^^
  104         struct symbol *sym;
  105         struct annotation *notes;
  106         struct map *map;
  107         int err = -1;
  108
  109         if (!he || !he->ms.sym)
  110                 return -1;

This patch moves the values assignment after validating pointer 'he'.

Signed-off-by: Leo Yan 
Acked-by: Jiri Olsa 
Cc: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Alexey Budankov 
Cc: Alexios Zavras 
Cc: Andi Kleen 
Cc: Changbin Du 
Cc: David S. Miller 
Cc: Davidlohr Bueso 
Cc: Eric Saint-Etienne 
Cc: Jin Yao 
Cc: Konstantin Khlebnikov 
Cc: Mathieu Poirier 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Rasmus Villemoes 
Cc: Song Liu 
Cc: Suzuki Poulouse 
Cc: Thomas Gleixner 
Cc: Thomas Richter 
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/20190702103420.27540-4-leo.yan@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo

tools perf: Move from sane_ctype.h obtained from git to the Linux's original

2019-06-26T00:02:47+00:00

We got the sane_ctype.h headers from git and kept using it so far, but
since that code originally came from the kernel sources to the git
sources, perhaps its better to just use the one in the kernel, so that
we can leverage tools/perf/check_headers.sh to be notified when our copy
gets out of sync, i.e. when fixes or goodies are added to the code we've
copied.

This will help with things like tools/lib/string.c where we want to have
more things in common with the kernel, such as strim(), skip_spaces(),
etc so as to go on removing the things that we have in tools/perf/util/
and instead using the code in the kernel, indirectly and removing things
like EXPORT_SYMBOL(), etc, getting notified when fixes and improvements
are made to the original code.

Hopefully this also should help with reducing the difference of code
hosted in tools/ to the one in the kernel proper.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-7k9868l713wqtgo01xxygn12@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf string: Move 'dots' and 'graph_dotted_line' out of sane_ctype.h

2019-06-25T20:31:26+00:00

Those are not in that file in the git repo, lets move it from there so
that we get that sane ctype code fully isolated to allow getting it in
sync either with the git sources or better with the kernel sources
(include/linux/ctype.h + lib/ctype.h), that way we can use
check_headers.h to get notified when changes are made in the original
code so that we can cherry-pick.

Cc: Adrian Hunter 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Link: https://lkml.kernel.org/n/tip-ioh5sghn3943j0rxg6lb2dgs@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

Merge branch 'x86/cpu' into perf/core, to pick up dependent changes

2019-06-17T10:29:16+00:00

Signed-off-by: Ingo Molnar

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 251

2019-06-05T15:30:26+00:00

Based on 1 normalized pattern(s):

  released under the gpl v2 and only v2 not any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 12 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Steve Winslow 
Reviewed-by: Alexios Zavras 
Reviewed-by: Kate Stewart 
Reviewed-by: Allison Randal 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141332.526460839@linutronix.de
Signed-off-by: Greg Kroah-Hartman

perf top: Lower message level for failure on synthesizing events for pre-existing BPF programs

2019-05-28T21:37:45+00:00

Move it from being a pr_warning() to a pr_debug(). Also capitalize BPF
and explain what gets missing when we're not able to synthesize these
events: we'll not be able to resolve symbols, etc.

Reported-by: Ingo Molnar 
Cc: Adrian Hunter 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: Daniel Borkmann 
Cc: Jiri Olsa 
Cc: Luis Cláudio Gonçalves 
Cc: Martin KaFai Lau 
Cc: Namhyung Kim 
Cc: Song Liu 
Cc: Wang Nan 
Cc: Yonghong Song 
Link: https://lkml.kernel.org/n/tip-whpnfnw6xtd939odgt9bw9as@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf top: Add --namespaces option

2019-05-28T21:37:43+00:00

Since 'perf record' already have this option, let's have it for 'perf top'
as well.

Signed-off-by: Namhyung Kim 
Cc: Hari Bathini 
Cc: Jiri Olsa 
Cc: Krister Johansen 
Link: http://lkml.kernel.org/r/20190522053250.207156-4-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf top: Always sample time to satisfy needs of use of ordered queuing

2019-04-16T15:36:20+00:00

Bastian reported broken 'perf top -p PID' command, it won't display any
data.

The problem is that for -p option we monitor single thread, so we don't
enable time in samples, because it's not needed.

However since commit 16c66bc167cc we use ordered queues to stash data
plus later commits added logic for dropping samples in case there's big
load and we don't keep up. All this needs timestamp for sample. Enabling
it unconditionally for perf top.

Reported-by: Bastian Beischer 
Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: bastian beischer 
Fixes: 16c66bc167cc ("perf top: Add processing thread")
Link: http://lkml.kernel.org/r/20190415125333.27160-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Save bpf_prog_info and BTF of new BPF programs

2019-03-21T14:27:04+00:00

To fully annotate BPF programs with source code mapping, 4 different
information are needed:

    1) PERF_RECORD_KSYMBOL
    2) PERF_RECORD_BPF_EVENT
    3) bpf_prog_info
    4) btf

This patch handles 3) and 4) for BPF programs loaded after 'perf
record|top'.

For timely process of these information, a dedicated event is added to
the side band evlist.

When PERF_RECORD_BPF_EVENT is received via the side band event, the
polling thread gathers 3) and 4) vis sys_bpf and store them in perf_env.

This information is saved to perf.data at the end of 'perf record'.

Committer testing:

The 'wakeup_watermark' member in 'struct perf_event_attr' is inside a
unnamed union, so can't be used in a struct designated initialization
with older gccs, get it out of that, isolating as 'attr.wakeup_watermark
= 1;' to work with all gcc versions.

We also need to add '--no-bpf-event' to the 'perf record'
perf_event_attr tests in 'perf test', as the way that that test goes is
to intercept the events being setup and looking if they match the fields
described in the control files, since now it finds first the side band
event used to catch the PERF_RECORD_BPF_EVENT, they all fail.

With these issues fixed:

Same scenario as for testing BPF programs loaded before 'perf record' or
'perf top' starts, only start the BPF programs after 'perf record|top',
so that its information get collected by the sideband threads, the rest
works as for the programs loaded before start monitoring.

Add missing 'inline' to the bpf_event__add_sb_event() when
HAVE_LIBBPF_SUPPORT is not defined, fixing the build in systems without
binutils devel files installed.

Signed-off-by: Song Liu 
Reviewed-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexei Starovoitov 
Cc: Daniel Borkmann 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stanislav Fomichev 
Link: http://lkml.kernel.org/r/20190312053051.2690567-16-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Introduce side band thread

2019-03-21T14:27:03+00:00

This patch introduces side band thread that captures extended
information for events like PERF_RECORD_BPF_EVENT.

This new thread uses its own evlist that uses ring buffer with very low
watermark for lower latency.

To use side band thread, we need to:

1. add side band event(s) by calling perf_evlist__add_sb_event();
2. calls perf_evlist__start_sb_thread();
3. at the end of perf run, perf_evlist__stop_sb_thread().

In the next patch, we use this thread to handle PERF_RECORD_BPF_EVENT.

Committer notes:

Add fix by Jiri Olsa for when te sb_tread can't get started and then at
the end the stop_sb_thread() segfaults when joining the (non-existing)
thread.

That can happen when running 'perf top' or 'perf record' as a normal
user, for instance.

Further checks need to be done on top of this to more graciously handle
these possible failure scenarios.

Signed-off-by: Song Liu 
Reviewed-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexei Starovoitov 
Cc: Daniel Borkmann 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Stanislav Fomichev 
Link: http://lkml.kernel.org/r/20190312053051.2690567-15-songliubraving@fb.com
Signed-off-by: Arnaldo Carvalho de Melo