Re: [PATCH 03/40] fs: Convert alloc_inode_sb() to a macro
From: Petr Tesařík <hidden>
Date: 2023-05-02 12:52:57
Also in:
cgroups, linux-arch, linux-fsdevel, linux-iommu, linux-mm, linux-modules, lkml
On Mon, 1 May 2023 09:54:13 -0700 Suren Baghdasaryan [off-list ref] wrote:
quoted hunk ↗ jump to hunk
From: Kent Overstreet <kent.overstreet@linux.dev> We're introducing alloc tagging, which tracks memory allocations by callsite. Converting alloc_inode_sb() to a macro means allocations will be tracked by its caller, which is a bit more useful. Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev> Signed-off-by: Suren Baghdasaryan <surenb@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> --- include/linux/fs.h | 6 +----- 1 file changed, 1 insertion(+), 5 deletions(-)diff --git a/include/linux/fs.h b/include/linux/fs.h index 21a981680856..4905ce14db0b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h@@ -2699,11 +2699,7 @@ int setattr_should_drop_sgid(struct mnt_idmap *idmap, * This must be used for allocating filesystems specific inodes to set * up the inode reclaim context correctly. */ -static inline void * -alloc_inode_sb(struct super_block *sb, struct kmem_cache *cache, gfp_t gfp) -{ - return kmem_cache_alloc_lru(cache, &sb->s_inode_lru, gfp); -} +#define alloc_inode_sb(_sb, _cache, _gfp) kmem_cache_alloc_lru(_cache, &_sb->s_inode_lru, _gfp)
Honestly, I don't like this change. In general, pre-processor macros are ugly and error-prone. Besides, it works for you only because __kmem_cache_alloc_lru() is declared __always_inline (unless CONFIG_SLUB_TINY is defined, but then you probably don't want the tracking either). In any case, it's going to be difficult for people to understand why and how this works. If the actual caller of alloc_inode_sb() is needed, I'd rather add it as a parameter and pass down _RET_IP_ explicitly here. Just my two cents, Petr T