This is a note to let you know that I've just added the patch titled
perf build: Fix up broken capstone feature detection fast path
to the 6.10-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
perf-build-fix-up-broken-capstone-feature-detection-.patch
and it can be found in the queue-6.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit dfc8f940a5f28b4c63377c9e149f4651566c5fa3
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Date: Wed Aug 14 10:36:24 2024 -0300
perf build: Fix up broken capstone feature detection fast path
[ Upstream commit 4c55560f23d19051adc7e76818687a88448bef83 ]
The capstone devel headers define 'struct bpf_insn' in a way that clashes with
what is in the libbpf devel headers, so we so far need to avoid including both.
This is happening on the tools/build/feature/test-all.c file, where we try
building all the expected set of libraries to be normally available on a
system:
⬢[acme@toolbox perf-tools-next]$ cat /tmp/build/perf-tools-next/feature/test-all.make.output
In file included from test-bpf.c:3,
from test-all.c:150:
/home/acme/git/perf-tools-next/tools/include/uapi/linux/bpf.h:77:8: error: ‘bpf_insn’ defined as wrong kind of tag
77 | struct bpf_insn {
| ^~~~~~~~
⬢[acme@toolbox perf-tools-next]$ cat /tmp/build/perf-tools-next/feature/test-all.make.output
When doing so there is a trick where we define main to be
main_test_libcapstone, then include the individual
tools/build/feture/test-libcapstone.c capability query test, and then we undef
'main' because we'll do it all over again with the next expected library to
be tested (at this time 'lzma').
To complete this mechanism we need to, in test-all.c 'main' routine, to
call main_test_libcapstone(), which isn't being done, so the effect of
adding references to capstone in test-all.c are not achieved.
The only thing that is happening is that test-all.c is failing to build and thus
all the tests will have to be done individually, which nullifies the test-all.c
single build speedup.
So lets remove references to capstone from test-all.c to see if this makes it
build again so that we get faster builds or go on fixing up whatever is
preventing us to get that benefit.
Nothing: after this fix we get a clean test-all.c build and get the build speedup back:
⬢[acme@toolbox perf-tools-next]$ cat /tmp/build/perf-tools-next/feature/test-all.make.output
⬢[acme@toolbox perf-tools-next]$ cat /tmp/build/perf-tools-next/feature/test-all.
test-all.bin test-all.d test-all.make.output
⬢[acme@toolbox perf-tools-next]$ cat /tmp/build/perf-tools-next/feature/test-all.make.output
⬢[acme@toolbox perf-tools-next]$ ldd /tmp/build/perf-tools-next/feature/test-all.bin
linux-vdso.so.1 (0x00007f13277a1000)
libpython3.12.so.1.0 => /lib64/libpython3.12.so.1.0 (0x00007f1326e00000)
libm.so.6 => /lib64/libm.so.6 (0x00007f13274be000)
libtraceevent.so.1 => /lib64/libtraceevent.so.1 (0x00007f1327496000)
libtracefs.so.1 => /lib64/libtracefs.so.1 (0x00007f132746f000)
libcrypto.so.3 => /lib64/libcrypto.so.3 (0x00007f1326800000)
libunwind-x86_64.so.8 => /lib64/libunwind-x86_64.so.8 (0x00007f1327452000)
libunwind.so.8 => /lib64/libunwind.so.8 (0x00007f1327436000)
liblzma.so.5 => /lib64/liblzma.so.5 (0x00007f1327403000)
libdw.so.1 => /lib64/libdw.so.1 (0x00007f1326d6f000)
libz.so.1 => /lib64/libz.so.1 (0x00007f13273e2000)
libelf.so.1 => /lib64/libelf.so.1 (0x00007f1326d53000)
libnuma.so.1 => /lib64/libnuma.so.1 (0x00007f13273d4000)
libslang.so.2 => /lib64/libslang.so.2 (0x00007f1326400000)
libperl.so.5.38 => /lib64/libperl.so.5.38 (0x00007f1326000000)
libc.so.6 => /lib64/libc.so.6 (0x00007f1325e0f000)
libzstd.so.1 => /lib64/libzstd.so.1 (0x00007f1326741000)
/lib64/ld-linux-x86-64.so.2 (0x00007f13277a3000)
libbz2.so.1 => /lib64/libbz2.so.1 (0x00007f1326d3f000)
libcrypt.so.2 => /lib64/libcrypt.so.2 (0x00007f1326d07000)
⬢[acme@toolbox perf-tools-next]$
And when having capstone-devel installed we get it detected and linked with
perf, allowing us to benefit from the features that it enables:
⬢[acme@toolbox perf-tools-next]$ rpm -q capstone-devel
capstone-devel-5.0.1-3.fc40.x86_64
⬢[acme@toolbox perf-tools-next]$ ldd /tmp/build/perf-tools-next/perf | grep capstone
libcapstone.so.5 => /lib64/libcapstone.so.5 (0x00007fe6a5c00000)
⬢[acme@toolbox perf-tools-next]$ /tmp/build/perf-tools-next/perf -vv | grep cap
libcapstone: [ on ] # HAVE_LIBCAPSTONE_SUPPORT
⬢[acme@toolbox perf-tools-next]$
Fixes: 8b767db3309595a2 ("perf: build: introduce the libcapstone")
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Andi Kleen <andi@xxxxxxxxxxxxxx>
Cc: Changbin Du <changbin.du@xxxxxxxxxx>
Cc: Ian Rogers <irogers@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Link: https://lore.kernel.org/lkml/Zry0sepD5Ppa5YKP@x1
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/tools/build/feature/test-all.c b/tools/build/feature/test-all.c
index dd0a18c2ef8fc..6f4bf386a3b5c 100644
--- a/tools/build/feature/test-all.c
+++ b/tools/build/feature/test-all.c
@@ -134,10 +134,6 @@
#undef main
#endif
-#define main main_test_libcapstone
-# include "test-libcapstone.c"
-#undef main
-
#define main main_test_lzma
# include "test-lzma.c"
#undef main
