tldr; Just FYI, I'm carrying this on the perf tools tree.
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 the changes from:
2a82bb02941fb53d ("statx: stx_subvol")
This silences this perf build warning:
Warning: Kernel ABI header differences:
diff -u tools/include/uapi/linux/stat.h include/uapi/linux/stat.h
Cc: Adrian Hunter <[email protected]>
Cc: Christian Brauner <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Kent Overstreet <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: https://lore.kernel.org/lkml/
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
---
tools/include/uapi/linux/stat.h | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/tools/include/uapi/linux/stat.h b/tools/include/uapi/linux/stat.h
index 2f2ee82d55175d05..67626d53531664d0 100644
--- a/tools/include/uapi/linux/stat.h
+++ b/tools/include/uapi/linux/stat.h
@@ -126,8 +126,9 @@ struct statx {
__u64 stx_mnt_id;
__u32 stx_dio_mem_align; /* Memory buffer alignment for direct I/O */
__u32 stx_dio_offset_align; /* File offset alignment for direct I/O */
+ __u64 stx_subvol; /* Subvolume identifier */
/* 0xa0 */
- __u64 __spare3[12]; /* Spare space for future expansion */
+ __u64 __spare3[11]; /* Spare space for future expansion */
/* 0x100 */
};
@@ -155,6 +156,7 @@ struct statx {
#define STATX_MNT_ID 0x00001000U /* Got stx_mnt_id */
#define STATX_DIOALIGN 0x00002000U /* Want/got direct I/O alignment info */
#define STATX_MNT_ID_UNIQUE 0x00004000U /* Want/got extended stx_mount_id */
+#define STATX_SUBVOL 0x00008000U /* Want/got stx_subvol */
#define STATX__RESERVED 0x80000000U /* Reserved for future struct statx expansion */
--
2.45.1