diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-02-23 09:33:08 -0800 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-02-23 09:33:08 -0800 |
| commit | 551d44200152cb26f75d2ef990aeb6185b7e37fd (patch) | |
| tree | fc52230991e1105774017711e6fb51ff3298491e /include/linux | |
| parent | 6de23f81a5e08be8fbf5e8d7e9febc72a5b5f27f (diff) | |
default_gfp(): avoid using the "newfangled" __VA_OPT__ trick
The default_gfp() helper that I added is not wrong, but it turns out
that it causes unnecessary headaches for 'sparse' which doesn't support
the use of __VA_OPT__ (introduced in C++20 and C23, and supported by gcc
and clang for a long time).
We do already use __VA_OPT__ in some other cases in the kernel (drm/xe
and btrfs), but it has been fairly limited. Now it triggers for pretty
much everything, and sparse ends up not working at all.
We can use the traditional gcc ',##__VA_ARGS__' syntax instead: it may
not be the "C standard" way and is slightly less natural in this
context, but it is the traditional model for this and avoids the sparse
problem.
Reported-and-tested-by: Ricardo Ribalda <ribalda@chromium.org>
Reported-and-tested-by: Richard Fitzgerald <rf@opensource.cirrus.com>
Reported-by: Ben Dooks <ben.dooks@codethink.co.uk>
Fixes: e19e1b480ac7 ("add default_gfp() helper macro and use it in the new *alloc_obj() helpers")
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/gfp.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/linux/gfp.h b/include/linux/gfp.h index 2b30a0529d48..90536b2bc42e 100644 --- a/include/linux/gfp.h +++ b/include/linux/gfp.h @@ -14,8 +14,8 @@ struct vm_area_struct; struct mempolicy; /* Helper macro to avoid gfp flags if they are the default one */ -#define __default_gfp(a,...) a -#define default_gfp(...) __default_gfp(__VA_ARGS__ __VA_OPT__(,) GFP_KERNEL) +#define __default_gfp(a,b,...) b +#define default_gfp(...) __default_gfp(,##__VA_ARGS__,GFP_KERNEL) /* Convert GFP flags to their corresponding migrate type */ #define GFP_MOVABLE_MASK (__GFP_RECLAIMABLE|__GFP_MOVABLE) |