@@ -422,7 +422,6 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
gfp_t gfp_mask)
{
struct page_frag_cache *nc;
- unsigned long flags;
struct sk_buff *skb;
bool pfmemalloc;
void *data;
@@ -443,13 +442,17 @@ struct sk_buff *__netdev_alloc_skb(struct net_device *dev, unsigned int len,
if (sk_memalloc_socks())
gfp_mask |= __GFP_MEMALLOC;
- local_irq_save(flags);
-
- nc = this_cpu_ptr(&netdev_alloc_cache);
- data = page_frag_alloc(nc, len, gfp_mask);
- pfmemalloc = nc->pfmemalloc;
-
- local_irq_restore(flags);
+ if (in_irq() || irqs_disabled()) {
+ nc = this_cpu_ptr(&netdev_alloc_cache);
+ data = page_frag_alloc(nc, len, gfp_mask);
+ pfmemalloc = nc->pfmemalloc;
+ } else {
+ local_bh_disable();
+ nc = this_cpu_ptr(&napi_alloc_cache.page);
+ data = page_frag_alloc(nc, len, gfp_mask);
+ pfmemalloc = nc->pfmemalloc;
+ local_bh_enable();
+ }
if (unlikely(!data))
return NULL;
__netdev_alloc_skb() can be used from any context and is used by NAPI and non-NAPI drivers. Non-NAPI drivers use it in interrupt context and NAPI drivers use it during initial allocation (->ndo_open() or ->ndo_change_mtu()). Some NAPI drivers share the same function for the initial allocation and the allocation in their NAPI callback. The interrupts are disabled in order to ensure locked access from every context to `netdev_alloc_cache'. Let __netdev_alloc_skb() check if interrupts are disabled. If they are, use `netdev_alloc_cache'. Otherwise disable BH and use `napi_alloc_cache.page'. The IRQ check is cheaper compared to disabling & enabling interrupts and memory allocation with disabled interrupts does not work on -RT. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- net/core/skbuff.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)