linux-stable.git/tools/build/feature, branch linux-5.7.y

tools build feature: Use CC and CXX from parent

2020-08-21T11:07:38+00:00

[ Upstream commit e3232c2f39acafd5a29128425bc30b9884642cfa ]

commit c8c188679ccf ("tools build: Use the same CC for feature detection
and actual build") changed these assignments from unconditional (:=) to
conditional (?=) so that they wouldn't clobber values from the
environment. However, conditional assignment does not work properly for
variables that Make implicitly sets, among which are CC and CXX. To
quote tools/scripts/Makefile.include, which handles this properly:

  # Makefiles suck: This macro sets a default value of $(2) for the
  # variable named by $(1), unless the variable has been set by
  # environment or command line. This is necessary for CC and AR
  # because make sets default values, so the simpler ?= approach
  # won't work as expected.

In other words, the conditional assignments will not run even if the
variables are not overridden in the environment; Make will set CC to
"cc" and CXX to "g++" when it starts[1], meaning the variables are not
empty by the time the conditional assignments are evaluated. This breaks
cross-compilation when CROSS_COMPILE is set but CC isn't, since "cc"
gets used for feature detection instead of the cross compiler (and
likewise for CXX).

To fix the issue, just pass down the values of CC and CXX computed by
the parent Makefile, which gets included by the Makefile that actually
builds whatever we're detecting features for and so is guaranteed to
have good values. This is a better solution anyway, since it means we
aren't trying to replicate the logic of the parent build system and so
don't risk it getting out of sync.

Leave PKG_CONFIG alone, since 1) there's no common logic to compute it
in Makefile.include, and 2) it's not an implicit variable, so
conditional assignment works properly.

[1] https://www.gnu.org/software/make/manual/html_node/Implicit-Variables.html

Fixes: c8c188679ccf ("tools build: Use the same CC for feature detection and actual build")
Signed-off-by: Thomas Hebb 
Acked-by: Jiri Olsa 
Cc: David Carrillo-Cisneros 
Cc: Ian Rogers 
Cc: Igor Lubashev 
Cc: Namhyung Kim 
Cc: Quentin Monnet 
Cc: Song Liu 
Cc: Stephane Eranian 
Cc: thomas hebb 
Link: http://lore.kernel.org/lkml/0a6e69d1736b0fa231a648f50b0cce5d8a6734ef.1595822871.git.tommyhebb@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo 
Signed-off-by: Sasha Levin

tools/build: tweak unused value workaround

2020-04-21T18:11:55+00:00

Clang has -Wself-assign enabled by default under -Wall, which always
gets -Werror'ed on this file, causing sync-compare-and-swap to be
disabled by default.

The generally-accepted way to spell "this value is intentionally
unused," is casting it to `void`.  This is accepted by both GCC and
Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3

Signed-off-by: George Burgess IV 
Signed-off-by: Andrew Morton 
Cc: Nick Desaulniers 
Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com
Signed-off-by: Linus Torvalds

Merge tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2020-04-05T19:26:24+00:00

Pull more perf updates from Thomas Gleixner:
 "Perf updates all over the place:

  core:

   - Support for cgroup tracking in samples to allow cgroup based
     analysis

  tools:

   - Support for cgroup analysis

   - Commandline option and hotkey for perf top to change the sort order

   - A set of fixes all over the place

   - Various build system related improvements

   - Updates of the X86 pmu event JSON data

   - Documentation updates"

* tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
  perf python: Fix clang detection to strip out options passed in $CC
  perf tools: Support Python 3.8+ in Makefile
  perf script: Fix invalid read of directory entry after closedir()
  perf script report: Fix SEGFAULT when using DWARF mode
  perf script: add -S/--symbols documentation
  perf pmu-events x86: Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
  perf events parser: Add missing Intel CPU events to parser
  perf script: Allow --symbol to accept hexadecimal addresses
  perf report/top TUI: Fix title line formatting
  perf top: Support hotkey to change sort order
  perf top: Support --group-sort-idx to change the sort order
  perf symbols: Fix arm64 gap between kernel start and module end
  perf build-test: Honour JOBS to override detection of number of cores
  perf script: Add --show-cgroup-events option
  perf top: Add --all-cgroups option
  perf record: Add --all-cgroups option
  perf record: Support synthesizing cgroup events
  perf report: Add 'cgroup' sort key
  perf cgroup: Maintain cgroup hierarchy
  perf tools: Basic support for CGROUP event
  ...

Merge tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx

2020-04-03T20:12:26+00:00

Pull SPDX updates from Greg KH:
 "Here are three SPDX patches for 5.7-rc1.

  One fixes up the SPDX tag for a single driver, while the other two go
  through the tree and add SPDX tags for all of the .gitignore files as
  needed.

  Nothing too complex, but you will get a merge conflict with your
  current tree, that should be trivial to handle (one file modified by
  two things, one file deleted.)

  All three of these have been in linux-next for a while, with no
  reported issues other than the merge conflict"

* tag 'spdx-5.7-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
  ASoC: MT6660: make spdxcheck.py happy
  .gitignore: add SPDX License Identifier
  .gitignore: remove too obvious comments

perf tools: Add file-handle feature test

2020-04-03T12:37:55+00:00

The file handle (FHANDLE) support is configurable so some systems might not
have it.  So add a config feature item to check it on build time so that we
don't add the cgroup tracking feature based on that.

Committer notes:

Had to make the test use the same construct as its later use in
synthetic-events.c, in the next patch in this series. i.e. make it be:

	struct {
		struct file_handle fh;
		uint64_t cgroup_id;
	} handle;

To cope with:

    CC       /tmp/build/perf/util/cloexec.o
  util/synthetic-events.c:428:22: error: field 'fh' with   CC       /tmp/build/perf/util/call-path.o
  variable sized type 'struct file_handle' not at the end of a struct or class is a GNU
        extension [-Werror,-Wgnu-variable-sized-type-not-at-end]
                  struct file_handle fh;
                                     ^
  1 error generated.

Deal with this at some point, i.e. investigate if the right thing is to
remove that -Wgnu-variable-sized-type-not-at-end from our CFLAGS, for
now do the test the same way as it is used looks more sensible.

Reported-by: Arnaldo Carvalho de Melo 
Signed-off-by: Namhyung Kim 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Alexander Shishkin 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20200402015249.3800462-1-namhyung@kernel.org
[ split from a larger patch, removed blank line at EOF ]
Signed-off-by: Arnaldo Carvalho de Melo

.gitignore: add SPDX License Identifier

2020-03-25T10:50:48+00:00

Add SPDX License Identifier to all .gitignore files.

Signed-off-by: Masahiro Yamada 
Signed-off-by: Greg Kroah-Hartman

bpftool: Only build bpftool-prog-profile if supported by clang

2020-03-12T23:08:33+00:00

bpftool-prog-profile requires clang to generate BTF for global variables.
When compared with older clang, skip this command. This is achieved by
adding a new feature, clang-bpf-global-var, to tools/build/feature.

Signed-off-by: Song Liu 
Signed-off-by: Daniel Borkmann 
Reviewed-by: Quentin Monnet 
Link: https://lore.kernel.org/bpf/20200312182332.3953408-2-songliubraving@fb.com

perf/ui/gtk: Fix gtk2 build

2020-01-14T15:40:33+00:00

Ravi Bangoria reported an issue when doing the gtk2 feature detection on
Fedora 31, where some types got deprecated:

  /usr/include/gtk-2.0/gtk/gtktypeutils.h:236:1: error: ‘GTypeDebugFlags’ is deprecated [-Werror=deprecated-declarations]
    236 | void            gtk_type_init   (GTypeDebugFlags    debug_flags);

Fix this for perf by allowing the compile to pass with deprecated
symbols via the -Wno-deprecated-declarations compiler directive.

Reported-by: Ravi Bangoria 
Signed-off-by: Jiri Olsa 
Tested-by: Ravi Bangoria 
Cc: Alexander Shishkin 
Cc: Jelle van der Waa 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Link: http://lore.kernel.org/lkml/20200113104358.123511-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo

tools build: Fix test-clang.cpp with Clang 8+

2020-01-14T15:02:19+00:00

LLVM rL344140 (included in Clang 8+) moved VFS from Clang to LLVM, so
paths to its include files have changed.

This broke the Clang test in tools/build - let's fix it.

Signed-off-by: Maciej S. Szmigiero 
Cc: Alexander Shishkin 
Cc: Denis Pronin 
Cc: Dennis Schridde 
Cc: Jiri Olsa 
Cc: Mark Rutland 
Cc: Namhyung Kim 
Cc: Naohiro Aota 
Cc: Peter Zijlstra 
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20191228171314.946469-1-mail@maciej.szmigiero.name
Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Allow to link with libbpf dynamicaly

2019-11-26T14:17:45+00:00

Currently we support only static linking with kernel's libbpf
(tools/lib/bpf). This patch adds libbpf package detection and support to
link perf with it dynamically.

The libbpf package status is displayed with:

  $ make VF=1
  Auto-detecting system features:
  ...
  ...                        libbpf: [ on  ]

It's not checked by default, because it's quite new.  Once it's on most
distros we can switch it on.

For the same reason it's not added to the test-all check.

Perf does not need advanced version of libbpf, so we can check just for
the base bpf_object__open function.

Adding new compile variable to detect libbpf package and link bpf
dynamically:

  $ make LIBBPF_DYNAMIC=1
    ...
    LINK     perf
  $ ldd perf | grep bpf
    libbpf.so.0 => /lib64/libbpf.so.0 (0x00007f46818bc000)

If libbpf is not installed, build stops with:

  Makefile.config:486: *** Error: No libbpf devel library found,\
  please install libbpf-devel.  Stop.

Committer testing:

  $ make LIBBPF_DYNAMIC=1 -C tools/perf O=/tmp/build/perf
  make: Entering directory '/home/acme/git/perf/tools/perf'
    BUILD:   Doing 'make -j8' parallel build
  Makefile.config:493: *** Error: No libbpf devel library found, please install libbpf-devel.  Stop.
  make[1]: *** [Makefile.perf:225: sub-make] Error 2
  make: *** [Makefile:70: all] Error 2
  make: Leaving directory '/home/acme/git/perf/tools/perf'
  $

Signed-off-by: Jiri Olsa 
Tested-by: Arnaldo Carvalho de Melo 
Cc: Toke Høiland-Jørgensen 
Cc: Alexander Shishkin 
Cc: Alexei Starovoitov 
Cc: Andrii Nakryiko 
Cc: Daniel Borkmann 
Cc: Jesper Dangaard Brouer 
Cc: Martin KaFai Lau 
Cc: Michael Petlan 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Song Liu 
Cc: Yonghong Song 
Cc: bpf@vger.kernel.org
Cc: netdev@vger.kernel.org
Link: http://lore.kernel.org/lkml/20191126121253.28253-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo