Commit graph

2 commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo
0c9f3a8597 libapi: Add missing header with NAME_MAX define to io_dir.h
Most systems get this indirectly, but some odd cases (some musl libc
systems) can't find it, so just add the header where NAME_MAX is defined
to avoid that.

Fixes: d118b08f7e ("tools lib api: Add io_dir an allocation free readdir alternative")
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: https://lore.kernel.org/r/20250310194534.265487-2-acme@kernel.org
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-13 00:29:36 -07:00
Ian Rogers
d118b08f7e tools lib api: Add io_dir an allocation free readdir alternative
glibc's opendir allocates a minimum of 32kb, when called recursively
for a directory tree the memory consumption can add up - nearly 300kb
during perf start-up when processing modules. Add a stack allocated
variant of readdir sized a little more than 1kb.

As getdents64 may be missing from libc, add support using syscall. As
the system call number maybe missing, add #defines for those.

Note, an earlier version of this patch had a feature test for
getdents64 but there were problems on certains distros where
getdents64 would be #define renamed to getdents breaking the code. The
syscall use was made uncondtional to work around this. There is
context in:
https://lore.kernel.org/lkml/20231207050433.1426834-1-irogers@google.com/

Signed-off-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20250222061015.303622-2-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-02-24 15:46:33 -08:00