diff options
| author | Christoph Hellwig <hch@lst.de> | 2026-05-28 11:34:32 +0200 |
|---|---|---|
| committer | Vlastimil Babka (SUSE) <vbabka@kernel.org> | 2026-06-03 18:20:43 +0200 |
| commit | 6bb0009862c5f0e89a6e4afc09b499a02576c7da (patch) | |
| tree | cfd862493532a55e8c724d338c3dd8ce17af019b /net/core | |
| parent | 5d6919055dec134de3c40167a490f33c74c12581 (diff) | |
| download | linux-next-6bb0009862c5f0e89a6e4afc09b499a02576c7da.tar.gz linux-next-6bb0009862c5f0e89a6e4afc09b499a02576c7da.zip | |
mm/slab: improve kmem_cache_alloc_bulk
The kmem_cache_alloc_bulk return value is weird. It returns the number
of allocated objects, but that must always be 0 or the requested number
based on the implementations and the handling in the callers, but that
assumption is not actually documented anywhere, which confuses automated
review tools.
Fix this by returning a bool if the allocation succeeded and adding a
kerneldoc comment explaining the API.
[rob.clark@oss.qualcomm.com: fixups in
msm_iommu_pagetable_prealloc_allocate() ]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alexander Lobakin <aleksander.lobakin@intel.com> # skbuff
Link: https://patch.msgid.link/20260528093437.2519248-2-hch@lst.de
Signed-off-by: Vlastimil Babka (SUSE) <vbabka@kernel.org>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/skbuff.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 7dad68e3b518..74f32c581403 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -288,11 +288,11 @@ static inline struct sk_buff *napi_skb_cache_get(bool alloc) local_lock_nested_bh(&napi_alloc_cache.bh_lock); if (unlikely(!nc->skb_count)) { - if (alloc) - nc->skb_count = kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, - GFP_ATOMIC | __GFP_NOWARN, - NAPI_SKB_CACHE_BULK, - nc->skb_cache); + if (alloc && kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, + GFP_ATOMIC | __GFP_NOWARN, + NAPI_SKB_CACHE_BULK, + nc->skb_cache)) + nc->skb_count = NAPI_SKB_CACHE_BULK; if (unlikely(!nc->skb_count)) { local_unlock_nested_bh(&napi_alloc_cache.bh_lock); return NULL; @@ -353,16 +353,18 @@ u32 napi_skb_cache_get_bulk(void **skbs, u32 n) /* No enough cached skbs. Try refilling the cache first */ bulk = min(NAPI_SKB_CACHE_SIZE - nc->skb_count, NAPI_SKB_CACHE_BULK); - nc->skb_count += kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, - GFP_ATOMIC | __GFP_NOWARN, bulk, - &nc->skb_cache[nc->skb_count]); + if (kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, + GFP_ATOMIC | __GFP_NOWARN, bulk, + &nc->skb_cache[nc->skb_count])) + nc->skb_count += bulk; if (likely(nc->skb_count >= n)) goto get; /* Still not enough. Bulk-allocate the missing part directly, zeroed */ - n -= kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, - GFP_ATOMIC | __GFP_ZERO | __GFP_NOWARN, - n - nc->skb_count, &skbs[nc->skb_count]); + if (kmem_cache_alloc_bulk(net_hotdata.skbuff_cache, + GFP_ATOMIC | __GFP_ZERO | __GFP_NOWARN, + n - nc->skb_count, &skbs[nc->skb_count])) + n = nc->skb_count; if (likely(nc->skb_count >= n)) goto get; |