linux-stable.git/tools/perf, branch v4.14.95

tools: fix cross-compile var clobbering

2019-01-13T09:01:02+00:00

commit 7ed1c1901fe52e6c5828deb155920b44b0adabb1 upstream.

Currently a number of Makefiles break when used with toolchains that
pass extra flags in CC and other cross-compile related variables (such
as --sysroot).

Thus we get this error when we use a toolchain that puts --sysroot in
the CC var:

  ~/src/linux/tools$ make iio
  [snip]
  iio_event_monitor.c:18:10: fatal error: unistd.h: No such file or directory
    #include 
             ^~~~~~~~~~

This occurs because we clobber several env vars related to
cross-compiling with lines like this:

  CC = $(CROSS_COMPILE)gcc

Although this will point to a valid cross-compiler, we lose any extra
flags that might exist in the CC variable, which can break toolchains
that rely on them (for example, those that use --sysroot).

This easily shows up using a Yocto SDK:

  $ . [snip]/sdk/environment-setup-cortexa8hf-neon-poky-linux-gnueabi

  $ echo $CC
  arm-poky-linux-gnueabi-gcc -march=armv7-a -mfpu=neon -mfloat-abi=hard
  -mcpu=cortex-a8
  --sysroot=[snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi

  $ echo $CROSS_COMPILE
  arm-poky-linux-gnueabi-

  $ echo ${CROSS_COMPILE}gcc
  krm-poky-linux-gnueabi-gcc

Although arm-poky-linux-gnueabi-gcc is a cross-compiler, we've lost the
--sysroot and other flags that enable us to find the right libraries to
link against, so we can't find unistd.h and other libraries and headers.
Normally with the --sysroot flag we would find unistd.h in the sdk
directory in the sysroot:

  $ find [snip]/sdk/sysroots -path '*/usr/include/unistd.h'
  [snip]/sdk/sysroots/cortexa8hf-neon-poky-linux-gnueabi/usr/include/unistd.h

The perf Makefile adds CC = $(CROSS_COMPILE)gcc if and only if CC is not
already set, and it compiles correctly with the above toolchain.

So, generalize the logic that perf uses in the common Makefile and
remove the manual CC = $(CROSS_COMPILE)gcc lines from each Makefile.

Note that this patch does not fix cross-compile for all the tools (some
have other bugs), but it does fix it for all except usb and acpi, which
still have other unrelated issues.

I tested both with and without the patch on native and cross-build and
there appear to be no regressions.

Link: http://lkml.kernel.org/r/20180107214028.23771-1-martin@martingkelly.com
Signed-off-by: Martin Kelly 
Acked-by: Mark Brown 
Cc: Tejun Heo 
Cc: Li Zefan 
Cc: Johannes Weiner 
Cc: Linus Walleij 
Cc: "K. Y. Srinivasan" 
Cc: Haiyang Zhang 
Cc: Stephen Hemminger 
Cc: Jonathan Cameron 
Cc: Pali Rohar 
Cc: Richard Purdie 
Cc: Jacek Anaszewski 
Cc: Pavel Machek 
Cc: Peter Zijlstra 
Cc: Ingo Molnar 
Cc: Arnaldo Carvalho de Melo 
Cc: Robert Moore 
Cc: Lv Zheng 
Cc: "Rafael J. Wysocki" 
Cc: Greg Kroah-Hartman 
Cc: Valentina Manea 
Cc: Shuah Khan 
Cc: Mario Limonciello 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Cc: Ignat Korchagin 
Signed-off-by: Greg Kroah-Hartman

perf pmu: Suppress potential format-truncation warning

2019-01-09T16:14:48+00:00

commit 11a64a05dc649815670b1be9fe63d205cb076401 upstream.

Depending on which functions are inlined in util/pmu.c, the snprintf()
calls in perf_pmu__parse_{scale,unit,per_pkg,snapshot}() might trigger a
warning:

  util/pmu.c: In function 'pmu_aliases':
  util/pmu.c:178:31: error: '%s' directive output may be truncated writing up to 255 bytes into a region of size between 0 and 4095 [-Werror=format-truncation=]
    snprintf(path, PATH_MAX, "%s/%s.unit", dir, name);
                               ^~

I found this when trying to build perf from Linux 3.16 with gcc 8.
However I can reproduce the problem in mainline if I force
__perf_pmu__new_alias() to be inlined.

Suppress this by using scnprintf() as has been done elsewhere in perf.

Signed-off-by: Ben Hutchings 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: stable@vger.kernel.org
Link: http://lkml.kernel.org/r/20181111184524.fux4taownc6ndbx6@decadent.org.uk
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Greg Kroah-Hartman

perf record: Synthesize features before events in pipe mode

2018-12-29T12:39:08+00:00

[ Upstream commit a2015516c5c0be932a69e1d3405c2fb03b4eacf1 ]

We need to synthesize events first, because some features works on top
of them (on report side).

Signed-off-by: Jiri Olsa 
Tested-by: Stephane Eranian 
Cc: Alexander Shishkin 
Cc: David Ahern 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lkml.kernel.org/r/20180314092205.23291-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf tools: Restore proper cwd on return from mnt namespace

2018-12-17T08:28:49+00:00

[ Upstream commit b01c1f69c8660eaeab7d365cd570103c5c073a02 ]

When reporting on 'record' server we try to retrieve/use the mnt
namespace of the profiled tasks. We use following API with cookie to
hold the return namespace, roughly:

  nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc)
    setns(newns, 0);
  ...
  new ns related open..
  ...
  nsinfo__mountns_exit(struct nscookie *nc)
    setns(nc->oldns)

Once finished we setns to old namespace, which also sets the current
working directory (cwd) to "/", trashing the cwd we had.

This is mostly fine, because we use absolute paths almost everywhere,
but it screws up 'perf diff':

  # perf diff
  failed to open perf.data: No such file or directory  (try 'perf record' first)
  ...

Adding the current working directory to be part of the cookie and
restoring it in the nsinfo__mountns_exit call.

Signed-off-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Krister Johansen 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Fixes: 843ff37bb59e ("perf symbols: Find symbols in different mount namespace")
Link: http://lkml.kernel.org/r/20181101170001.30019-1-jolsa@kernel.org
[ No need to check for NULL args for free(), use zfree() for struct members ]
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf test code-reading: Fix perf_env setup for PTI entry trampolines

2018-11-27T15:10:50+00:00

commit f6c66d73bb8192d357bb5fb8cd5826920f811d8c upstream.

The "Object code reading" test will not create maps for the PTI entry
trampolines unless the machine environment exists to show that the arch is
x86_64.

Signed-off-by: Adrian Hunter 
Reported-by: Arnaldo Carvalho de Melo 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Jiri Olsa 
Link: http://lkml.kernel.org/r/1528183800-21577-1-git-send-email-adrian.hunter@intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf machine: Workaround missing maps for x86 PTI entry trampolines

2018-11-27T15:10:50+00:00

commit 4d99e4136580d178e3523281a820be17bf814bf8 upstream.

On x86_64 the PTI entry trampolines are not in the kernel map created by
perf tools. That results in the addresses having no symbols and prevents
annotation.  It also causes Intel PT to have decoding errors at the
trampoline addresses.

Workaround that by creating maps for the trampolines.

At present the kernel does not export information revealing where the
trampolines are.  Until that happens, the addresses are hardcoded.

Signed-off-by: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Jiri Olsa 
Cc: Joerg Roedel 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf machine: Add nr_cpus_avail()

2018-11-27T15:10:50+00:00

commit 9cecca325ea879c84fcd31a5e609a514c1a1dbd1 upstream.

Add a function to return the number of the machine's available CPUs.

Signed-off-by: Adrian Hunter 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Jiri Olsa 
Cc: Joerg Roedel 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526986485-6562-5-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf tools: Fix kernel_start for PTI on x86

2018-11-27T15:10:50+00:00

commit 19422a9f2a3be7f3a046285ffae4cbb571aa853a upstream.

On x86_64, PTI entry trampolines are less than the start of kernel text,
but still above 2^63. So leave kernel_start = 1ULL << 63 for x86_64.

Signed-off-by: Adrian Hunter 
Tested-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Joerg Roedel 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526548928-20790-7-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf machine: Add machine__is() to identify machine arch

2018-11-27T15:10:50+00:00

commit dbbd34a666ee117d0e39e71a47f38f02c4a5c698 upstream.

Add a function to identify the machine architecture.

Signed-off-by: Adrian Hunter 
Tested-by: Jiri Olsa 
Cc: Alexander Shishkin 
Cc: Andi Kleen 
Cc: Andy Lutomirski 
Cc: Dave Hansen 
Cc: H. Peter Anvin 
Cc: Joerg Roedel 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: x86@kernel.org
Link: http://lkml.kernel.org/r/1526548928-20790-6-git-send-email-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

perf tools: Fix undefined symbol scnprintf in libperf-jvmti.so

2018-11-27T15:10:49+00:00

[ Upstream commit 6ac2226229d931153331a93d90655a3de05b9290 ]

Currently jvmti agent can not be used because function scnprintf is not
present in the agent libperf-jvmti.so. As a result the JVM when using
such agent to record JITed code profiling information will fail on
looking up scnprintf:

  java: symbol lookup error: lib/libperf-jvmti.so: undefined symbol: scnprintf

This commit fixes that by reverting to the use of snprintf, that can be
looked up, instead of scnprintf, adding a proper check for the returned
value in order to print a better error message when the jitdump file
pathname is too long. Checking the returned value also helps to comply
with some recent gcc versions, like gcc8, which will fail due to
truncated writing checks related to the -Werror=format-truncation= flag.

Signed-off-by: Gustavo Romero 
Acked-by: Jiri Olsa 
LPU-Reference: 1541117601-18937-2-git-send-email-gromero@linux.vnet.ibm.com
Link: https://lkml.kernel.org/n/tip-mvpxxxy7wnzaj74cq75muw3f@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin