[PATCH 0/5] perf build: nondistro build tidyups

[PATCH 0/5] perf build: nondistro build tidyups

[James Clark]

nondistro builds now require a specific version of libbfd, so this adds
an error when doing an explicit BUILD_NONDISTRO build and some other
related tidyups.

I'm not sure if the intention is to skip build-tests if something is
missing, but I see it was done for libbpf versions, so I added the same
for libbfd. This is the main thing that I hit, that build-test all of a
sudden stopped working for me.

The first commit is also a cherry pick of an old commit that seemed to
have been accidentally reverted in the unrelated change linked in the
trailers.

---
James Clark (4):
      perf build: Do all non-distro feature checks in one go
      perf build: Remove unused libbfd-buildid feature test
      perf build: Feature test for libbfd thread safety API
      perf build: Skip nondistro build test if libbfd is old

Roberto Sassu (1):
      perf build: Remove FEATURE_CHECK_LDFLAGS-disassembler-{four-args,init-styled} setting

 tools/build/Makefile.feature                 |  2 +-
 tools/build/feature/Makefile                 |  4 +--
 tools/build/feature/test-libbfd-buildid.c    |  8 -----
 tools/build/feature/test-libbfd-threadsafe.c | 18 ++++++++++
 tools/perf/Makefile.config                   | 54 ++++++++++------------------
 tools/perf/tests/make                        |  5 +++
 6 files changed, 45 insertions(+), 46 deletions(-)
---
base-commit: cbd41c6d4c26c161a2b0e70ad411d3885ff13507
change-id: 20251223-james-libbfd-feat-check-e0cd09d2c1e1

Best regards,
-- 
James Clark <james.clark@linaro.org>

[PATCH 1/5] perf build: Remove FEATURE_CHECK_LDFLAGS-disassembler-{four-args,init-styled} setting

[James Clark]

From: Roberto Sassu <roberto.sassu@huawei.com>

As the building mechanism is now able to retry detection with different
combinations of linking flags, setting
FEATURE_CHECK_LDFLAGS-disassembler-four-args and
FEATURE_CHECK_LDFLAGS-disassembler-init-styled is not necessary anymore,
so remove it.

Committer notes:

Use the same technique to find the set of bfd-related libraries to link as in:

  3308ffc5016e6136 ("tools, build: Retry detection of bfd-related features")

Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andres Freund <andres@anarazel.de>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Monnet <quentin@isovalent.com>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@google.com>
Cc: bpf@vger.kernel.org
Cc: llvm@lists.linux.dev
Link: https://lore.kernel.org/r/20220719170555.2576993-3-roberto.sassu@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
[Cherry pick to fix accidental removal in commit ad5f604e186a]
Signed-off-by: James Clark <james.clark@linaro.org>
---
 tools/perf/Makefile.config | 12 +++---------
 1 file changed, 3 insertions(+), 9 deletions(-)

diff --git a/tools/perf/Makefile.config b/tools/perf/Makefile.config
index bd9f4804d56b..ea6636a09a95 100644
--- a/tools/perf/Makefile.config
+++ b/tools/perf/Makefile.config
@@ -379,8 +379,8 @@ ifneq ($(TCMALLOC),)
 endif
 
 ifeq ($(FEATURES_DUMP),)
-# We will display at the end of this Makefile.config, using $(call feature_display_entries)
-# As we may retry some feature detection here, see the disassembler-four-args case, for instance
+# We will display at the end of this Makefile.config, using $(call feature_display_entries),
+# as we may retry some feature detection here.
   FEATURE_DISPLAY_DEFERRED := 1
 include $(srctree)/tools/build/Makefile.feature
 else
@@ -927,8 +927,6 @@ ifdef BUILD_NONDISTRO
 
   ifeq ($(feature-libbfd), 1)
     EXTLIBS += -lbfd -lopcodes
-    FEATURE_CHECK_LDFLAGS-disassembler-four-args = -lbfd -lopcodes -ldl
-    FEATURE_CHECK_LDFLAGS-disassembler-init-styled = -lbfd -lopcodes -ldl
   else
     # we are on a system that requires -liberty and (maybe) -lz
     # to link against -lbfd; test each case individually here
@@ -940,13 +938,9 @@ ifdef BUILD_NONDISTRO
 
     ifeq ($(feature-libbfd-liberty), 1)
       EXTLIBS += -lbfd -lopcodes -liberty
-      FEATURE_CHECK_LDFLAGS-disassembler-four-args += -liberty -ldl
-      FEATURE_CHECK_LDFLAGS-disassembler-init-styled += -liberty -ldl
     else
       ifeq ($(feature-libbfd-liberty-z), 1)
         EXTLIBS += -lbfd -lopcodes -liberty -lz
-        FEATURE_CHECK_LDFLAGS-disassembler-four-args += -liberty -lz -ldl
-        FEATURE_CHECK_LDFLAGS-disassembler-init-styled += -liberty -lz -ldl
       endif
     endif
     $(call feature_check,disassembler-four-args)
@@ -1324,6 +1318,6 @@ endif
 
 # re-generate FEATURE-DUMP as we may have called feature_check, found out
 # extra libraries to add to LDFLAGS of some other test and then redo those
-# tests, see the block about libbfd, disassembler-four-args, for instance.
+# tests.
 $(shell rm -f $(FEATURE_DUMP_FILENAME))
 $(foreach feat,$(FEATURE_TESTS),$(shell echo "$(call feature_assign,$(feat))" >> $(FEATURE_DUMP_FILENAME)))

-- 
2.34.1

Re: [PATCH 0/5] perf build: nondistro build tidyups

[Arnaldo Carvalho de Melo]

On Tue, Dec 23, 2025 at 05:00:23PM +0000, James Clark wrote:
> nondistro builds now require a specific version of libbfd, so this adds
> an error when doing an explicit BUILD_NONDISTRO build and some other
> related tidyups.
> 
> I'm not sure if the intention is to skip build-tests if something is
> missing, but I see it was done for libbpf versions, so I added the same
> for libbfd. This is the main thing that I hit, that build-test all of a
> sudden stopped working for me.
> 
> The first commit is also a cherry pick of an old commit that seemed to
> have been accidentally reverted in the unrelated change linked in the
> trailers.

Thanks, applied to perf-tools-next,

- Arnaldo
 
> ---
> James Clark (4):
>       perf build: Do all non-distro feature checks in one go
>       perf build: Remove unused libbfd-buildid feature test
>       perf build: Feature test for libbfd thread safety API
>       perf build: Skip nondistro build test if libbfd is old
> 
> Roberto Sassu (1):
>       perf build: Remove FEATURE_CHECK_LDFLAGS-disassembler-{four-args,init-styled} setting
> 
>  tools/build/Makefile.feature                 |  2 +-
>  tools/build/feature/Makefile                 |  4 +--
>  tools/build/feature/test-libbfd-buildid.c    |  8 -----
>  tools/build/feature/test-libbfd-threadsafe.c | 18 ++++++++++
>  tools/perf/Makefile.config                   | 54 ++++++++++------------------
>  tools/perf/tests/make                        |  5 +++
>  6 files changed, 45 insertions(+), 46 deletions(-)
> ---
> base-commit: cbd41c6d4c26c161a2b0e70ad411d3885ff13507
> change-id: 20251223-james-libbfd-feat-check-e0cd09d2c1e1
> 
> Best regards,
> -- 
> James Clark <james.clark@linaro.org>