archives/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-03-08 03:04:51 +01:00
Code Issues Projects Releases Packages Wiki Activity Actions

mm/slab: pass __GFP_NOWARN to refill_sheaf() if fallback is available

Browse source 
When refill_sheaf() is called, failing to refill the sheaf doesn't
necessarily mean the allocation will fail because a fallback path
might be available and serve the allocation request.

Suppress spurious warnings by passing __GFP_NOWARN along with
__GFP_NOMEMALLOC whenever a fallback path is available.

When the caller is alloc_full_sheaf() or __pcs_replace_empty_main(),
the kernel always falls back to the slowpath (__slab_alloc_node()).
For __prefill_sheaf_pfmemalloc(), the fallback path is available
only when gfp_pfmemalloc_allowed() returns true.

Reported-and-tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Closes: https://lore.kernel.org/linux-mm/aZt2-oS9lkmwT7Ch@debian.local
Fixes: 1ce20c28ea ("slab: handle pfmemalloc slabs properly with sheaves")
Link: https://lore.kernel.org/linux-mm/aZwSreGj9-HHdD-j@hyeyoo
Signed-off-by: Harry Yoo <harry.yoo@oracle.com>
Link: https://patch.msgid.link/20260223133322.16705-1-harry.yoo@oracle.com
Tested-by: Mikhail Gavrilov <mikhail.v.gavrilov@gmail.com>
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
This commit is contained in:
Harry Yoo 2026-02-23 22:33:22 +09:00 • committed by Vlastimil Babka (SUSE)
parent 6de23f81a5
commit 021ca6b670
1 changed files with 9 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

13
mm/slub.c
View file

@ -2822,7 +2822,7 @@ static struct slab_sheaf *alloc_full_sheaf(struct kmem_cache *s, gfp_t gfp)
if (!sheaf)
return NULL;
if (refill_sheaf(s, sheaf, gfp | __GFP_NOMEMALLOC)) {
if (refill_sheaf(s, sheaf, gfp | __GFP_NOMEMALLOC | __GFP_NOWARN)) {
free_empty_sheaf(s, sheaf);
return NULL;
}
@ -4575,7 +4575,7 @@ __pcs_replace_empty_main(struct kmem_cache *s, struct slub_percpu_sheaves *pcs,
return NULL;
if (empty) {
if (!refill_sheaf(s, empty, gfp | __GFP_NOMEMALLOC)) {
if (!refill_sheaf(s, empty, gfp | __GFP_NOMEMALLOC | __GFP_NOWARN)) {
full = empty;
} else {
/*
@ -4890,9 +4890,14 @@ EXPORT_SYMBOL(kmem_cache_alloc_node_noprof);
static int __prefill_sheaf_pfmemalloc(struct kmem_cache *s,
struct slab_sheaf *sheaf, gfp_t gfp)
{
int ret = 0;
gfp_t gfp_nomemalloc;
int ret;
ret = refill_sheaf(s, sheaf, gfp | __GFP_NOMEMALLOC);
gfp_nomemalloc = gfp | __GFP_NOMEMALLOC;
if (gfp_pfmemalloc_allowed(gfp))
gfp_nomemalloc |= __GFP_NOWARN;
ret = refill_sheaf(s, sheaf, gfp_nomemalloc);
if (likely(!ret || !gfp_pfmemalloc_allowed(gfp)))
return ret;