tldr; Just FYI, I'm carrying this on the perf tools tree.
- Arnaldo
Full explanation:
There used to be no copies, with tools/ code using kernel headers
directly. From time to time tools/perf/ broke due to legitimate kernel
hacking. At some point Linus complained about such direct usage. Then we
adopted the current model.
The way these headers are used in perf are not restricted to just
including them to compile something.
There are sometimes used in scripts that convert defines into string
tables, etc, so some change may break one of these scripts, or new MSRs
may use some different #define pattern, etc.
E.g.:
$ ls -1 tools/perf/trace/beauty/*.sh | head -5
tools/perf/trace/beauty/arch_errno_names.sh
tools/perf/trace/beauty/drm_ioctl.sh
tools/perf/trace/beauty/fadvise.sh
tools/perf/trace/beauty/fsconfig.sh
tools/perf/trace/beauty/fsmount.sh
$
$ tools/perf/trace/beauty/fadvise.sh
static const char *fadvise_advices[] = {
[0] = "NORMAL",
[1] = "RANDOM",
[2] = "SEQUENTIAL",
[3] = "WILLNEED",
[4] = "DONTNEED",
[5] = "NOREUSE",
};
$
The tools/perf/check-headers.sh script, part of the tools/ build
process, points out changes in the original files.
So its important not to touch the copies in tools/ when doing changes in
the original kernel headers, that will be done later, when
check-headers.sh inform about the change to the perf tools hackers.
---
To pick up the changes in:
1ab33c03145d0f6c ("asm-generic: make sparse happy with odd-sized put_unaligned_*()")
Addressing this perf tools build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/asm-generic/unaligned.h include/asm-generic/unaligned.h
Cc: Adrian Hunter <[email protected]>
Cc: Dmitry Torokhov <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/include/asm-generic/unaligned.h | 24 ++++++++++++------------
1 file changed, 12 insertions(+), 12 deletions(-)
diff --git a/tools/include/asm-generic/unaligned.h b/tools/include/asm-generic/unaligned.h
index 2fd551915c2025ee..cdd2fd078027afc9 100644
--- a/tools/include/asm-generic/unaligned.h
+++ b/tools/include/asm-generic/unaligned.h
@@ -105,9 +105,9 @@ static inline u32 get_unaligned_le24(const void *p)
static inline void __put_unaligned_be24(const u32 val, u8 *p)
{
- *p++ = val >> 16;
- *p++ = val >> 8;
- *p++ = val;
+ *p++ = (val >> 16) & 0xff;
+ *p++ = (val >> 8) & 0xff;
+ *p++ = val & 0xff;
}
static inline void put_unaligned_be24(const u32 val, void *p)
@@ -117,9 +117,9 @@ static inline void put_unaligned_be24(const u32 val, void *p)
static inline void __put_unaligned_le24(const u32 val, u8 *p)
{
- *p++ = val;
- *p++ = val >> 8;
- *p++ = val >> 16;
+ *p++ = val & 0xff;
+ *p++ = (val >> 8) & 0xff;
+ *p++ = (val >> 16) & 0xff;
}
static inline void put_unaligned_le24(const u32 val, void *p)
@@ -129,12 +129,12 @@ static inline void put_unaligned_le24(const u32 val, void *p)
static inline void __put_unaligned_be48(const u64 val, u8 *p)
{
- *p++ = val >> 40;
- *p++ = val >> 32;
- *p++ = val >> 24;
- *p++ = val >> 16;
- *p++ = val >> 8;
- *p++ = val;
+ *p++ = (val >> 40) & 0xff;
+ *p++ = (val >> 32) & 0xff;
+ *p++ = (val >> 24) & 0xff;
+ *p++ = (val >> 16) & 0xff;
+ *p++ = (val >> 8) & 0xff;
+ *p++ = val & 0xff;
}
static inline void put_unaligned_be48(const u64 val, void *p)
--
2.43.0