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-rw-r--r--net/core/skbuff.c117
1 files changed, 77 insertions, 40 deletions
diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7a338fb55cc4..56ed17cd2151 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -336,59 +336,85 @@ struct netdev_alloc_cache {
unsigned int pagecnt_bias;
};
static DEFINE_PER_CPU(struct netdev_alloc_cache, netdev_alloc_cache);
+static DEFINE_PER_CPU(struct netdev_alloc_cache, napi_alloc_cache);
-static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+static struct page *__page_frag_refill(struct netdev_alloc_cache *nc,
+ gfp_t gfp_mask)
{
- struct netdev_alloc_cache *nc;
- void *data = NULL;
- int order;
- unsigned long flags;
+ const unsigned int order = NETDEV_FRAG_PAGE_MAX_ORDER;
+ struct page *page = NULL;
+ gfp_t gfp = gfp_mask;
+
+ if (order) {
+ gfp_mask |= __GFP_COMP | __GFP_NOWARN | __GFP_NORETRY;
+ page = alloc_pages_node(NUMA_NO_NODE, gfp_mask, order);
+ nc->frag.size = PAGE_SIZE << (page ? order : 0);
+ }
- local_irq_save(flags);
- nc = this_cpu_ptr(&netdev_alloc_cache);
- if (unlikely(!nc->frag.page)) {
+ if (unlikely(!page))
+ page = alloc_pages_node(NUMA_NO_NODE, gfp, 0);
+
+ nc->frag.page = page;
+
+ return page;
+}
+
+static void *__alloc_page_frag(struct netdev_alloc_cache __percpu *cache,
+ unsigned int fragsz, gfp_t gfp_mask)
+{
+ struct netdev_alloc_cache *nc = this_cpu_ptr(cache);
+ struct page *page = nc->frag.page;
+ unsigned int size;
+ int offset;
+
+ if (unlikely(!page)) {
refill:
- for (order = NETDEV_FRAG_PAGE_MAX_ORDER; ;) {
- gfp_t gfp = gfp_mask;
+ page = __page_frag_refill(nc, gfp_mask);
+ if (!page)
+ return NULL;
+
+ /* if size can vary use frag.size else just use PAGE_SIZE */
+ size = NETDEV_FRAG_PAGE_MAX_ORDER ? nc->frag.size : PAGE_SIZE;
- if (order)
- gfp |= __GFP_COMP | __GFP_NOWARN;
- nc->frag.page = alloc_pages(gfp, order);
- if (likely(nc->frag.page))
- break;
- if (--order < 0)
- goto end;
- }
- nc->frag.size = PAGE_SIZE << order;
/* Even if we own the page, we do not use atomic_set().
* This would break get_page_unless_zero() users.
*/
- atomic_add(NETDEV_PAGECNT_MAX_BIAS - 1,
- &nc->frag.page->_count);
- nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS;
- nc->frag.offset = 0;
+ atomic_add(size - 1, &page->_count);
+
+ /* reset page count bias and offset to start of new frag */
+ nc->pagecnt_bias = size;
+ nc->frag.offset = size;
}
- if (nc->frag.offset + fragsz > nc->frag.size) {
- if (atomic_read(&nc->frag.page->_count) != nc->pagecnt_bias) {
- if (!atomic_sub_and_test(nc->pagecnt_bias,
- &nc->frag.page->_count))
- goto refill;
- /* OK, page count is 0, we can safely set it */
- atomic_set(&nc->frag.page->_count,
- NETDEV_PAGECNT_MAX_BIAS);
- } else {
- atomic_add(NETDEV_PAGECNT_MAX_BIAS - nc->pagecnt_bias,
- &nc->frag.page->_count);
- }
- nc->pagecnt_bias = NETDEV_PAGECNT_MAX_BIAS;
- nc->frag.offset = 0;
+ offset = nc->frag.offset - fragsz;
+ if (unlikely(offset < 0)) {
+ if (!atomic_sub_and_test(nc->pagecnt_bias, &page->_count))
+ goto refill;
+
+ /* if size can vary use frag.size else just use PAGE_SIZE */
+ size = NETDEV_FRAG_PAGE_MAX_ORDER ? nc->frag.size : PAGE_SIZE;
+
+ /* OK, page count is 0, we can safely set it */
+ atomic_set(&page->_count, size);
+
+ /* reset page count bias and offset to start of new frag */
+ nc->pagecnt_bias = size;
+ offset = size - fragsz;
}
- data = page_address(nc->frag.page) + nc->frag.offset;
- nc->frag.offset += fragsz;
nc->pagecnt_bias--;
-end:
+ nc->frag.offset = offset;
+
+ return page_address(page) + offset;
+}
+
+static void *__netdev_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+{
+ unsigned long flags;
+ void *data;
+
+ local_irq_save(flags);
+ data = __alloc_page_frag(&netdev_alloc_cache, fragsz, gfp_mask);
local_irq_restore(flags);
return data;
}
@@ -406,6 +432,17 @@ void *netdev_alloc_frag(unsigned int fragsz)
}
EXPORT_SYMBOL(netdev_alloc_frag);
+static void *__napi_alloc_frag(unsigned int fragsz, gfp_t gfp_mask)
+{
+ return __alloc_page_frag(&napi_alloc_cache, fragsz, gfp_mask);
+}
+
+void *napi_alloc_frag(unsigned int fragsz)
+{
+ return __napi_alloc_frag(fragsz, GFP_ATOMIC | __GFP_COLD);
+}
+EXPORT_SYMBOL(napi_alloc_frag);
+
/**
* __netdev_alloc_skb - allocate an skbuff for rx on a specific device
* @dev: network device to receive on