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Diffstat (limited to 'net/core/page_pool.c')
-rw-r--r--net/core/page_pool.c537
1 files changed, 395 insertions, 142 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 2abe6e919224..265a729431bb 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -11,7 +11,10 @@
#include <linux/slab.h>
#include <linux/device.h>
+#include <net/netdev_lock.h>
+#include <net/netdev_rx_queue.h>
#include <net/page_pool/helpers.h>
+#include <net/page_pool/memory_provider.h>
#include <net/xdp.h>
#include <linux/dma-direction.h>
@@ -24,8 +27,13 @@
#include <trace/events/page_pool.h>
+#include "dev.h"
+#include "mp_dmabuf_devmem.h"
+#include "netmem_priv.h"
#include "page_pool_priv.h"
+DEFINE_STATIC_KEY_FALSE(page_pool_mem_providers);
+
#define DEFER_TIME (msecs_to_jiffies(1000))
#define DEFER_WARN_INTERVAL (60 * HZ)
@@ -145,9 +153,9 @@ u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats)
EXPORT_SYMBOL(page_pool_ethtool_stats_get);
#else
-#define alloc_stat_inc(pool, __stat)
-#define recycle_stat_inc(pool, __stat)
-#define recycle_stat_add(pool, __stat, val)
+#define alloc_stat_inc(...) do { } while (0)
+#define recycle_stat_inc(...) do { } while (0)
+#define recycle_stat_add(...) do { } while (0)
#endif
static bool page_pool_producer_lock(struct page_pool *pool)
@@ -187,6 +195,8 @@ static int page_pool_init(struct page_pool *pool,
int cpuid)
{
unsigned int ring_qsize = 1024; /* Default */
+ struct netdev_rx_queue *rxq;
+ int err;
page_pool_struct_check();
@@ -194,17 +204,14 @@ static int page_pool_init(struct page_pool *pool,
memcpy(&pool->slow, &params->slow, sizeof(pool->slow));
pool->cpuid = cpuid;
+ pool->dma_sync_for_cpu = true;
/* Validate only known flags were used */
if (pool->slow.flags & ~PP_FLAG_ALL)
return -EINVAL;
if (pool->p.pool_size)
- ring_qsize = pool->p.pool_size;
-
- /* Sanity limit mem that can be pinned down */
- if (ring_qsize > 32768)
- return -E2BIG;
+ ring_qsize = min(pool->p.pool_size, 16384);
/* DMA direction is either DMA_FROM_DEVICE or DMA_BIDIRECTIONAL.
* DMA_BIDIRECTIONAL is for allowing page used for DMA sending,
@@ -265,18 +272,56 @@ static int page_pool_init(struct page_pool *pool,
/* Driver calling page_pool_create() also call page_pool_destroy() */
refcount_set(&pool->user_cnt, 1);
- if (pool->dma_map)
- get_device(pool->p.dev);
+ xa_init_flags(&pool->dma_mapped, XA_FLAGS_ALLOC1);
+
+ if (pool->slow.flags & PP_FLAG_ALLOW_UNREADABLE_NETMEM) {
+ netdev_assert_locked(pool->slow.netdev);
+ rxq = __netif_get_rx_queue(pool->slow.netdev,
+ pool->slow.queue_idx);
+ pool->mp_priv = rxq->mp_params.mp_priv;
+ pool->mp_ops = rxq->mp_params.mp_ops;
+ }
+
+ if (pool->mp_ops) {
+ if (!pool->dma_map || !pool->dma_sync) {
+ err = -EOPNOTSUPP;
+ goto free_ptr_ring;
+ }
+
+ if (WARN_ON(!is_kernel_rodata((unsigned long)pool->mp_ops))) {
+ err = -EFAULT;
+ goto free_ptr_ring;
+ }
+
+ err = pool->mp_ops->init(pool);
+ if (err) {
+ pr_warn("%s() mem-provider init failed %d\n", __func__,
+ err);
+ goto free_ptr_ring;
+ }
+
+ static_branch_inc(&page_pool_mem_providers);
+ } else if (pool->p.order > MAX_PAGE_ORDER) {
+ err = -EINVAL;
+ goto free_ptr_ring;
+ }
return 0;
+
+free_ptr_ring:
+ ptr_ring_cleanup(&pool->ring, NULL);
+ xa_destroy(&pool->dma_mapped);
+#ifdef CONFIG_PAGE_POOL_STATS
+ if (!pool->system)
+ free_percpu(pool->recycle_stats);
+#endif
+ return err;
}
static void page_pool_uninit(struct page_pool *pool)
{
ptr_ring_cleanup(&pool->ring, NULL);
-
- if (pool->dma_map)
- put_device(pool->p.dev);
+ xa_destroy(&pool->dma_mapped);
#ifdef CONFIG_PAGE_POOL_STATS
if (!pool->system)
@@ -328,7 +373,7 @@ struct page_pool *page_pool_create(const struct page_pool_params *params)
}
EXPORT_SYMBOL(page_pool_create);
-static void page_pool_return_page(struct page_pool *pool, netmem_ref netmem);
+static void page_pool_return_netmem(struct page_pool *pool, netmem_ref netmem);
static noinline netmem_ref page_pool_refill_alloc_cache(struct page_pool *pool)
{
@@ -358,7 +403,7 @@ static noinline netmem_ref page_pool_refill_alloc_cache(struct page_pool *pool)
if (unlikely(!netmem))
break;
- if (likely(page_to_nid(netmem_to_page(netmem)) == pref_nid)) {
+ if (likely(netmem_is_pref_nid(netmem, pref_nid))) {
pool->alloc.cache[pool->alloc.count++] = netmem;
} else {
/* NUMA mismatch;
@@ -366,7 +411,7 @@ static noinline netmem_ref page_pool_refill_alloc_cache(struct page_pool *pool)
* (2) break out to fallthrough to alloc_pages_node.
* This limit stress on page buddy alloactor.
*/
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
alloc_stat_inc(pool, waive);
netmem = 0;
break;
@@ -417,13 +462,70 @@ page_pool_dma_sync_for_device(const struct page_pool *pool,
netmem_ref netmem,
u32 dma_sync_size)
{
- if (pool->dma_sync && dma_dev_need_sync(pool->p.dev))
- __page_pool_dma_sync_for_device(pool, netmem, dma_sync_size);
+ if (pool->dma_sync && dma_dev_need_sync(pool->p.dev)) {
+ rcu_read_lock();
+ /* re-check under rcu_read_lock() to sync with page_pool_scrub() */
+ if (pool->dma_sync)
+ __page_pool_dma_sync_for_device(pool, netmem,
+ dma_sync_size);
+ rcu_read_unlock();
+ }
+}
+
+static int page_pool_register_dma_index(struct page_pool *pool,
+ netmem_ref netmem, gfp_t gfp)
+{
+ int err = 0;
+ u32 id;
+
+ if (unlikely(!PP_DMA_INDEX_BITS))
+ goto out;
+
+ if (in_softirq())
+ err = xa_alloc(&pool->dma_mapped, &id, netmem_to_page(netmem),
+ PP_DMA_INDEX_LIMIT, gfp);
+ else
+ err = xa_alloc_bh(&pool->dma_mapped, &id, netmem_to_page(netmem),
+ PP_DMA_INDEX_LIMIT, gfp);
+ if (err) {
+ WARN_ONCE(err != -ENOMEM, "couldn't track DMA mapping, please report to netdev@");
+ goto out;
+ }
+
+ netmem_set_dma_index(netmem, id);
+out:
+ return err;
+}
+
+static int page_pool_release_dma_index(struct page_pool *pool,
+ netmem_ref netmem)
+{
+ struct page *old, *page = netmem_to_page(netmem);
+ unsigned long id;
+
+ if (unlikely(!PP_DMA_INDEX_BITS))
+ return 0;
+
+ id = netmem_get_dma_index(netmem);
+ if (!id)
+ return -1;
+
+ if (in_softirq())
+ old = xa_cmpxchg(&pool->dma_mapped, id, page, NULL, 0);
+ else
+ old = xa_cmpxchg_bh(&pool->dma_mapped, id, page, NULL, 0);
+ if (old != page)
+ return -1;
+
+ netmem_set_dma_index(netmem, 0);
+
+ return 0;
}
-static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem)
+static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem, gfp_t gfp)
{
dma_addr_t dma;
+ int err;
/* Setup DMA mapping: use 'struct page' area for storing DMA-addr
* since dma_addr_t can be either 32 or 64 bits and does not always fit
@@ -437,47 +539,28 @@ static bool page_pool_dma_map(struct page_pool *pool, netmem_ref netmem)
if (dma_mapping_error(pool->p.dev, dma))
return false;
- if (page_pool_set_dma_addr_netmem(netmem, dma))
+ if (page_pool_set_dma_addr_netmem(netmem, dma)) {
+ WARN_ONCE(1, "unexpected DMA address, please report to netdev@");
goto unmap_failed;
+ }
+
+ err = page_pool_register_dma_index(pool, netmem, gfp);
+ if (err)
+ goto unset_failed;
page_pool_dma_sync_for_device(pool, netmem, pool->p.max_len);
return true;
+unset_failed:
+ page_pool_set_dma_addr_netmem(netmem, 0);
unmap_failed:
- WARN_ONCE(1, "unexpected DMA address, please report to netdev@");
dma_unmap_page_attrs(pool->p.dev, dma,
PAGE_SIZE << pool->p.order, pool->p.dma_dir,
DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING);
return false;
}
-static void page_pool_set_pp_info(struct page_pool *pool, netmem_ref netmem)
-{
- struct page *page = netmem_to_page(netmem);
-
- page->pp = pool;
- page->pp_magic |= PP_SIGNATURE;
-
- /* Ensuring all pages have been split into one fragment initially:
- * page_pool_set_pp_info() is only called once for every page when it
- * is allocated from the page allocator and page_pool_fragment_page()
- * is dirtying the same cache line as the page->pp_magic above, so
- * the overhead is negligible.
- */
- page_pool_fragment_netmem(netmem, 1);
- if (pool->has_init_callback)
- pool->slow.init_callback(netmem, pool->slow.init_arg);
-}
-
-static void page_pool_clear_pp_info(netmem_ref netmem)
-{
- struct page *page = netmem_to_page(netmem);
-
- page->pp_magic = 0;
- page->pp = NULL;
-}
-
static struct page *__page_pool_alloc_page_order(struct page_pool *pool,
gfp_t gfp)
{
@@ -488,7 +571,7 @@ static struct page *__page_pool_alloc_page_order(struct page_pool *pool,
if (unlikely(!page))
return NULL;
- if (pool->dma_map && unlikely(!page_pool_dma_map(pool, page_to_netmem(page)))) {
+ if (pool->dma_map && unlikely(!page_pool_dma_map(pool, page_to_netmem(page), gfp))) {
put_page(page);
return NULL;
}
@@ -504,8 +587,8 @@ static struct page *__page_pool_alloc_page_order(struct page_pool *pool,
}
/* slow path */
-static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool,
- gfp_t gfp)
+static noinline netmem_ref __page_pool_alloc_netmems_slow(struct page_pool *pool,
+ gfp_t gfp)
{
const int bulk = PP_ALLOC_CACHE_REFILL;
unsigned int pp_order = pool->p.order;
@@ -513,6 +596,12 @@ static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool,
netmem_ref netmem;
int i, nr_pages;
+ /* Unconditionally set NOWARN if allocating from NAPI.
+ * Drivers forget to set it, and OOM reports on packet Rx are useless.
+ */
+ if ((gfp & GFP_ATOMIC) == GFP_ATOMIC)
+ gfp |= __GFP_NOWARN;
+
/* Don't support bulk alloc for high-order pages */
if (unlikely(pp_order))
return page_to_netmem(__page_pool_alloc_page_order(pool, gfp));
@@ -521,12 +610,11 @@ static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool,
if (unlikely(pool->alloc.count > 0))
return pool->alloc.cache[--pool->alloc.count];
- /* Mark empty alloc.cache slots "empty" for alloc_pages_bulk_array */
+ /* Mark empty alloc.cache slots "empty" for alloc_pages_bulk */
memset(&pool->alloc.cache, 0, sizeof(void *) * bulk);
- nr_pages = alloc_pages_bulk_array_node(gfp,
- pool->p.nid, bulk,
- (struct page **)pool->alloc.cache);
+ nr_pages = alloc_pages_bulk_node(gfp, pool->p.nid, bulk,
+ (struct page **)pool->alloc.cache);
if (unlikely(!nr_pages))
return 0;
@@ -535,7 +623,7 @@ static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool,
*/
for (i = 0; i < nr_pages; i++) {
netmem = pool->alloc.cache[i];
- if (dma_map && unlikely(!page_pool_dma_map(pool, netmem))) {
+ if (dma_map && unlikely(!page_pool_dma_map(pool, netmem, gfp))) {
put_page(netmem_to_page(netmem));
continue;
}
@@ -563,7 +651,7 @@ static noinline netmem_ref __page_pool_alloc_pages_slow(struct page_pool *pool,
/* For using page_pool replace: alloc_pages() API calls, but provide
* synchronization guarantee for allocation side.
*/
-netmem_ref page_pool_alloc_netmem(struct page_pool *pool, gfp_t gfp)
+netmem_ref page_pool_alloc_netmems(struct page_pool *pool, gfp_t gfp)
{
netmem_ref netmem;
@@ -573,17 +661,20 @@ netmem_ref page_pool_alloc_netmem(struct page_pool *pool, gfp_t gfp)
return netmem;
/* Slow-path: cache empty, do real allocation */
- netmem = __page_pool_alloc_pages_slow(pool, gfp);
+ if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops)
+ netmem = pool->mp_ops->alloc_netmems(pool, gfp);
+ else
+ netmem = __page_pool_alloc_netmems_slow(pool, gfp);
return netmem;
}
-EXPORT_SYMBOL(page_pool_alloc_netmem);
+EXPORT_SYMBOL(page_pool_alloc_netmems);
+ALLOW_ERROR_INJECTION(page_pool_alloc_netmems, NULL);
struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp)
{
- return netmem_to_page(page_pool_alloc_netmem(pool, gfp));
+ return netmem_to_page(page_pool_alloc_netmems(pool, gfp));
}
EXPORT_SYMBOL(page_pool_alloc_pages);
-ALLOW_ERROR_INJECTION(page_pool_alloc_pages, NULL);
/* Calculate distance between two u32 values, valid if distance is below 2^(31)
* https://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution
@@ -609,8 +700,30 @@ s32 page_pool_inflight(const struct page_pool *pool, bool strict)
return inflight;
}
-static __always_inline void __page_pool_release_page_dma(struct page_pool *pool,
- netmem_ref netmem)
+void page_pool_set_pp_info(struct page_pool *pool, netmem_ref netmem)
+{
+ netmem_set_pp(netmem, pool);
+ netmem_or_pp_magic(netmem, PP_SIGNATURE);
+
+ /* Ensuring all pages have been split into one fragment initially:
+ * page_pool_set_pp_info() is only called once for every page when it
+ * is allocated from the page allocator and page_pool_fragment_page()
+ * is dirtying the same cache line as the page->pp_magic above, so
+ * the overhead is negligible.
+ */
+ page_pool_fragment_netmem(netmem, 1);
+ if (pool->has_init_callback)
+ pool->slow.init_callback(netmem, pool->slow.init_arg);
+}
+
+void page_pool_clear_pp_info(netmem_ref netmem)
+{
+ netmem_clear_pp_magic(netmem);
+ netmem_set_pp(netmem, NULL);
+}
+
+static __always_inline void __page_pool_release_netmem_dma(struct page_pool *pool,
+ netmem_ref netmem)
{
dma_addr_t dma;
@@ -620,6 +733,9 @@ static __always_inline void __page_pool_release_page_dma(struct page_pool *pool,
*/
return;
+ if (page_pool_release_dma_index(pool, netmem))
+ return;
+
dma = page_pool_get_dma_addr_netmem(netmem);
/* When page is unmapped, it cannot be returned to our pool */
@@ -634,11 +750,16 @@ static __always_inline void __page_pool_release_page_dma(struct page_pool *pool,
* a regular page (that will eventually be returned to the normal
* page-allocator via put_page).
*/
-void page_pool_return_page(struct page_pool *pool, netmem_ref netmem)
+static void page_pool_return_netmem(struct page_pool *pool, netmem_ref netmem)
{
int count;
+ bool put;
- __page_pool_release_page_dma(pool, netmem);
+ put = true;
+ if (static_branch_unlikely(&page_pool_mem_providers) && pool->mp_ops)
+ put = pool->mp_ops->release_netmem(pool, netmem);
+ else
+ __page_pool_release_netmem_dma(pool, netmem);
/* This may be the last page returned, releasing the pool, so
* it is not safe to reference pool afterwards.
@@ -646,8 +767,10 @@ void page_pool_return_page(struct page_pool *pool, netmem_ref netmem)
count = atomic_inc_return_relaxed(&pool->pages_state_release_cnt);
trace_page_pool_state_release(pool, netmem, count);
- page_pool_clear_pp_info(netmem);
- put_page(netmem_to_page(netmem));
+ if (put) {
+ page_pool_clear_pp_info(netmem);
+ put_page(netmem_to_page(netmem));
+ }
/* An optimization would be to call __free_pages(page, pool->p.order)
* knowing page is not part of page-cache (thus avoiding a
* __page_cache_release() call).
@@ -656,19 +779,16 @@ void page_pool_return_page(struct page_pool *pool, netmem_ref netmem)
static bool page_pool_recycle_in_ring(struct page_pool *pool, netmem_ref netmem)
{
- int ret;
- /* BH protection not needed if current is softirq */
- if (in_softirq())
- ret = ptr_ring_produce(&pool->ring, (__force void *)netmem);
- else
- ret = ptr_ring_produce_bh(&pool->ring, (__force void *)netmem);
+ bool in_softirq, ret;
- if (!ret) {
+ /* BH protection not needed if current is softirq */
+ in_softirq = page_pool_producer_lock(pool);
+ ret = !__ptr_ring_produce(&pool->ring, (__force void *)netmem);
+ if (ret)
recycle_stat_inc(pool, ring);
- return true;
- }
+ page_pool_producer_unlock(pool, in_softirq);
- return false;
+ return ret;
}
/* Only allow direct recycling in special circumstances, into the
@@ -692,8 +812,9 @@ static bool page_pool_recycle_in_cache(netmem_ref netmem,
static bool __page_pool_page_can_be_recycled(netmem_ref netmem)
{
- return page_ref_count(netmem_to_page(netmem)) == 1 &&
- !page_is_pfmemalloc(netmem_to_page(netmem));
+ return netmem_is_net_iov(netmem) ||
+ (page_ref_count(netmem_to_page(netmem)) == 1 &&
+ !page_is_pfmemalloc(netmem_to_page(netmem)));
}
/* If the page refcnt == 1, this will try to recycle the page.
@@ -728,6 +849,7 @@ __page_pool_put_page(struct page_pool *pool, netmem_ref netmem,
/* Page found as candidate for recycling */
return netmem;
}
+
/* Fallback/non-XDP mode: API user have elevated refcnt.
*
* Many drivers split up the page into fragments, and some
@@ -742,7 +864,7 @@ __page_pool_put_page(struct page_pool *pool, netmem_ref netmem,
* will be invoking put_page.
*/
recycle_stat_inc(pool, released_refcnt);
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
return 0;
}
@@ -752,6 +874,10 @@ static bool page_pool_napi_local(const struct page_pool *pool)
const struct napi_struct *napi;
u32 cpuid;
+ /* On PREEMPT_RT the softirq can be preempted by the consumer */
+ if (IS_ENABLED(CONFIG_PREEMPT_RT))
+ return false;
+
if (unlikely(!in_softirq()))
return false;
@@ -776,12 +902,12 @@ void page_pool_put_unrefed_netmem(struct page_pool *pool, netmem_ref netmem,
if (!allow_direct)
allow_direct = page_pool_napi_local(pool);
- netmem =
- __page_pool_put_page(pool, netmem, dma_sync_size, allow_direct);
+ netmem = __page_pool_put_page(pool, netmem, dma_sync_size,
+ allow_direct);
if (netmem && !page_pool_recycle_in_ring(pool, netmem)) {
/* Cache full, fallback to free pages */
recycle_stat_inc(pool, ring_full);
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
}
}
EXPORT_SYMBOL(page_pool_put_unrefed_netmem);
@@ -794,69 +920,104 @@ void page_pool_put_unrefed_page(struct page_pool *pool, struct page *page,
}
EXPORT_SYMBOL(page_pool_put_unrefed_page);
-/**
- * page_pool_put_page_bulk() - release references on multiple pages
- * @pool: pool from which pages were allocated
- * @data: array holding page pointers
- * @count: number of pages in @data
- *
- * Tries to refill a number of pages into the ptr_ring cache holding ptr_ring
- * producer lock. If the ptr_ring is full, page_pool_put_page_bulk()
- * will release leftover pages to the page allocator.
- * page_pool_put_page_bulk() is suitable to be run inside the driver NAPI tx
- * completion loop for the XDP_REDIRECT use case.
- *
- * Please note the caller must not use data area after running
- * page_pool_put_page_bulk(), as this function overwrites it.
- */
-void page_pool_put_page_bulk(struct page_pool *pool, void **data,
- int count)
+static void page_pool_recycle_ring_bulk(struct page_pool *pool,
+ netmem_ref *bulk,
+ u32 bulk_len)
{
- int i, bulk_len = 0;
- bool allow_direct;
bool in_softirq;
+ u32 i;
- allow_direct = page_pool_napi_local(pool);
-
- for (i = 0; i < count; i++) {
- netmem_ref netmem = page_to_netmem(virt_to_head_page(data[i]));
-
- /* It is not the last user for the page frag case */
- if (!page_pool_is_last_ref(netmem))
- continue;
-
- netmem = __page_pool_put_page(pool, netmem, -1, allow_direct);
- /* Approved for bulk recycling in ptr_ring cache */
- if (netmem)
- data[bulk_len++] = (__force void *)netmem;
- }
-
- if (!bulk_len)
- return;
-
- /* Bulk producer into ptr_ring page_pool cache */
+ /* Bulk produce into ptr_ring page_pool cache */
in_softirq = page_pool_producer_lock(pool);
+
for (i = 0; i < bulk_len; i++) {
- if (__ptr_ring_produce(&pool->ring, data[i])) {
+ if (__ptr_ring_produce(&pool->ring, (__force void *)bulk[i])) {
/* ring full */
recycle_stat_inc(pool, ring_full);
break;
}
}
- recycle_stat_add(pool, ring, i);
+
page_pool_producer_unlock(pool, in_softirq);
+ recycle_stat_add(pool, ring, i);
- /* Hopefully all pages was return into ptr_ring */
+ /* Hopefully all pages were returned into ptr_ring */
if (likely(i == bulk_len))
return;
- /* ptr_ring cache full, free remaining pages outside producer lock
- * since put_page() with refcnt == 1 can be an expensive operation
+ /*
+ * ptr_ring cache is full, free remaining pages outside producer lock
+ * since put_page() with refcnt == 1 can be an expensive operation.
*/
for (; i < bulk_len; i++)
- page_pool_return_page(pool, (__force netmem_ref)data[i]);
+ page_pool_return_netmem(pool, bulk[i]);
+}
+
+/**
+ * page_pool_put_netmem_bulk() - release references on multiple netmems
+ * @data: array holding netmem references
+ * @count: number of entries in @data
+ *
+ * Tries to refill a number of netmems into the ptr_ring cache holding ptr_ring
+ * producer lock. If the ptr_ring is full, page_pool_put_netmem_bulk()
+ * will release leftover netmems to the memory provider.
+ * page_pool_put_netmem_bulk() is suitable to be run inside the driver NAPI tx
+ * completion loop for the XDP_REDIRECT use case.
+ *
+ * Please note the caller must not use data area after running
+ * page_pool_put_netmem_bulk(), as this function overwrites it.
+ */
+void page_pool_put_netmem_bulk(netmem_ref *data, u32 count)
+{
+ u32 bulk_len = 0;
+
+ for (u32 i = 0; i < count; i++) {
+ netmem_ref netmem = netmem_compound_head(data[i]);
+
+ if (page_pool_unref_and_test(netmem))
+ data[bulk_len++] = netmem;
+ }
+
+ count = bulk_len;
+ while (count) {
+ netmem_ref bulk[XDP_BULK_QUEUE_SIZE];
+ struct page_pool *pool = NULL;
+ bool allow_direct;
+ u32 foreign = 0;
+
+ bulk_len = 0;
+
+ for (u32 i = 0; i < count; i++) {
+ struct page_pool *netmem_pp;
+ netmem_ref netmem = data[i];
+
+ netmem_pp = netmem_get_pp(netmem);
+ if (unlikely(!pool)) {
+ pool = netmem_pp;
+ allow_direct = page_pool_napi_local(pool);
+ } else if (netmem_pp != pool) {
+ /*
+ * If the netmem belongs to a different
+ * page_pool, save it for another round.
+ */
+ data[foreign++] = netmem;
+ continue;
+ }
+
+ netmem = __page_pool_put_page(pool, netmem, -1,
+ allow_direct);
+ /* Approved for bulk recycling in ptr_ring cache */
+ if (netmem)
+ bulk[bulk_len++] = netmem;
+ }
+
+ if (bulk_len)
+ page_pool_recycle_ring_bulk(pool, bulk, bulk_len);
+
+ count = foreign;
+ }
}
-EXPORT_SYMBOL(page_pool_put_page_bulk);
+EXPORT_SYMBOL(page_pool_put_netmem_bulk);
static netmem_ref page_pool_drain_frag(struct page_pool *pool,
netmem_ref netmem)
@@ -872,7 +1033,7 @@ static netmem_ref page_pool_drain_frag(struct page_pool *pool,
return netmem;
}
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
return 0;
}
@@ -886,7 +1047,7 @@ static void page_pool_free_frag(struct page_pool *pool)
if (!netmem || page_pool_unref_netmem(netmem, drain_count))
return;
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
}
netmem_ref page_pool_alloc_frag_netmem(struct page_pool *pool,
@@ -905,13 +1066,14 @@ netmem_ref page_pool_alloc_frag_netmem(struct page_pool *pool,
if (netmem && *offset + size > max_size) {
netmem = page_pool_drain_frag(pool, netmem);
if (netmem) {
+ recycle_stat_inc(pool, cached);
alloc_stat_inc(pool, fast);
goto frag_reset;
}
}
if (!netmem) {
- netmem = page_pool_alloc_netmem(pool, gfp);
+ netmem = page_pool_alloc_netmems(pool, gfp);
if (unlikely(!netmem)) {
pool->frag_page = 0;
return 0;
@@ -929,7 +1091,6 @@ frag_reset:
pool->frag_users++;
pool->frag_offset = *offset + size;
- alloc_stat_inc(pool, fast);
return netmem;
}
EXPORT_SYMBOL(page_pool_alloc_frag_netmem);
@@ -949,11 +1110,11 @@ static void page_pool_empty_ring(struct page_pool *pool)
/* Empty recycle ring */
while ((netmem = (__force netmem_ref)ptr_ring_consume_bh(&pool->ring))) {
/* Verify the refcnt invariant of cached pages */
- if (!(page_ref_count(netmem_to_page(netmem)) == 1))
+ if (!(netmem_ref_count(netmem) == 1))
pr_crit("%s() page_pool refcnt %d violation\n",
__func__, netmem_ref_count(netmem));
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
}
}
@@ -964,6 +1125,12 @@ static void __page_pool_destroy(struct page_pool *pool)
page_pool_unlist(pool);
page_pool_uninit(pool);
+
+ if (pool->mp_ops) {
+ pool->mp_ops->destroy(pool);
+ static_branch_dec(&page_pool_mem_providers);
+ }
+
kfree(pool);
}
@@ -980,14 +1147,35 @@ static void page_pool_empty_alloc_cache_once(struct page_pool *pool)
*/
while (pool->alloc.count) {
netmem = pool->alloc.cache[--pool->alloc.count];
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
}
}
static void page_pool_scrub(struct page_pool *pool)
{
+ unsigned long id;
+ void *ptr;
+
page_pool_empty_alloc_cache_once(pool);
- pool->destroy_cnt++;
+ if (!pool->destroy_cnt++ && pool->dma_map) {
+ if (pool->dma_sync) {
+ /* Disable page_pool_dma_sync_for_device() */
+ pool->dma_sync = false;
+
+ /* Make sure all concurrent returns that may see the old
+ * value of dma_sync (and thus perform a sync) have
+ * finished before doing the unmapping below. Skip the
+ * wait if the device doesn't actually need syncing, or
+ * if there are no outstanding mapped pages.
+ */
+ if (dma_dev_need_sync(pool->p.dev) &&
+ !xa_empty(&pool->dma_mapped))
+ synchronize_net();
+ }
+
+ xa_for_each(&pool->dma_mapped, id, ptr)
+ __page_pool_release_netmem_dma(pool, page_to_netmem((struct page *)ptr));
+ }
/* No more consumers should exist, but producers could still
* be in-flight.
@@ -997,10 +1185,14 @@ static void page_pool_scrub(struct page_pool *pool)
static int page_pool_release(struct page_pool *pool)
{
+ bool in_softirq;
int inflight;
page_pool_scrub(pool);
inflight = page_pool_inflight(pool, true);
+ /* Acquire producer lock to make sure producers have exited. */
+ in_softirq = page_pool_producer_lock(pool);
+ page_pool_producer_unlock(pool, in_softirq);
if (!inflight)
__page_pool_destroy(pool);
@@ -1015,7 +1207,13 @@ static void page_pool_release_retry(struct work_struct *wq)
int inflight;
inflight = page_pool_release(pool);
- if (!inflight)
+ /* In rare cases, a driver bug may cause inflight to go negative.
+ * Don't reschedule release if inflight is 0 or negative.
+ * - If 0, the page_pool has been destroyed
+ * - if negative, we will never recover
+ * in both cases no reschedule is necessary.
+ */
+ if (inflight <= 0)
return;
/* Periodic warning for page pools the user can't see */
@@ -1041,6 +1239,35 @@ void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *),
pool->xdp_mem_id = mem->id;
}
+/**
+ * page_pool_enable_direct_recycling() - mark page pool as owned by NAPI
+ * @pool: page pool to modify
+ * @napi: NAPI instance to associate the page pool with
+ *
+ * Associate a page pool with a NAPI instance for lockless page recycling.
+ * This is useful when a new page pool has to be added to a NAPI instance
+ * without disabling that NAPI instance, to mark the point at which control
+ * path "hands over" the page pool to the NAPI instance. In most cases driver
+ * can simply set the @napi field in struct page_pool_params, and does not
+ * have to call this helper.
+ *
+ * The function is idempotent, but does not implement any refcounting.
+ * Single page_pool_disable_direct_recycling() will disable recycling,
+ * no matter how many times enable was called.
+ */
+void page_pool_enable_direct_recycling(struct page_pool *pool,
+ struct napi_struct *napi)
+{
+ if (READ_ONCE(pool->p.napi) == napi)
+ return;
+ WARN_ON(!napi || pool->p.napi);
+
+ mutex_lock(&page_pools_lock);
+ WRITE_ONCE(pool->p.napi, napi);
+ mutex_unlock(&page_pools_lock);
+}
+EXPORT_SYMBOL(page_pool_enable_direct_recycling);
+
void page_pool_disable_direct_recycling(struct page_pool *pool)
{
/* Disable direct recycling based on pool->cpuid.
@@ -1051,13 +1278,11 @@ void page_pool_disable_direct_recycling(struct page_pool *pool)
if (!pool->p.napi)
return;
- /* To avoid races with recycling and additional barriers make sure
- * pool and NAPI are unlinked when NAPI is disabled.
- */
- WARN_ON(!test_bit(NAPI_STATE_SCHED, &pool->p.napi->state));
- WARN_ON(READ_ONCE(pool->p.napi->list_owner) != -1);
+ napi_assert_will_not_race(pool->p.napi);
+ mutex_lock(&page_pools_lock);
WRITE_ONCE(pool->p.napi, NULL);
+ mutex_unlock(&page_pools_lock);
}
EXPORT_SYMBOL(page_pool_disable_direct_recycling);
@@ -1095,7 +1320,35 @@ void page_pool_update_nid(struct page_pool *pool, int new_nid)
/* Flush pool alloc cache, as refill will check NUMA node */
while (pool->alloc.count) {
netmem = pool->alloc.cache[--pool->alloc.count];
- page_pool_return_page(pool, netmem);
+ page_pool_return_netmem(pool, netmem);
}
}
EXPORT_SYMBOL(page_pool_update_nid);
+
+bool net_mp_niov_set_dma_addr(struct net_iov *niov, dma_addr_t addr)
+{
+ return page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), addr);
+}
+
+/* Associate a niov with a page pool. Should follow with a matching
+ * net_mp_niov_clear_page_pool()
+ */
+void net_mp_niov_set_page_pool(struct page_pool *pool, struct net_iov *niov)
+{
+ netmem_ref netmem = net_iov_to_netmem(niov);
+
+ page_pool_set_pp_info(pool, netmem);
+
+ pool->pages_state_hold_cnt++;
+ trace_page_pool_state_hold(pool, netmem, pool->pages_state_hold_cnt);
+}
+
+/* Disassociate a niov from a page pool. Should only be used in the
+ * ->release_netmem() path.
+ */
+void net_mp_niov_clear_page_pool(struct net_iov *niov)
+{
+ netmem_ref netmem = net_iov_to_netmem(niov);
+
+ page_pool_clear_pp_info(netmem);
+}