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-rw-r--r--net/core/page_pool.c1012
1 files changed, 731 insertions, 281 deletions
diff --git a/net/core/page_pool.c b/net/core/page_pool.c
index 9b203d8660e4..265a729431bb 100644
--- a/net/core/page_pool.c
+++ b/net/core/page_pool.c
@@ -5,12 +5,16 @@
* Copyright (C) 2016 Red Hat, Inc.
*/
+#include <linux/error-injection.h>
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/device.h>
-#include <net/page_pool.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>
@@ -19,15 +23,25 @@
#include <linux/mm.h> /* for put_page() */
#include <linux/poison.h>
#include <linux/ethtool.h>
+#include <linux/netdevice.h>
#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)
-#define BIAS_MAX LONG_MAX
+#define BIAS_MAX (LONG_MAX >> 1)
#ifdef CONFIG_PAGE_POOL_STATS
+static DEFINE_PER_CPU(struct page_pool_recycle_stats, pp_system_recycle_stats);
+
/* alloc_stat_inc is intended to be used in softirq context */
#define alloc_stat_inc(pool, __stat) (pool->alloc_stats.__stat++)
/* recycle_stat_inc is safe to use when preemption is possible. */
@@ -57,7 +71,18 @@ static const char pp_stats[][ETH_GSTRING_LEN] = {
"rx_pp_recycle_released_ref",
};
-bool page_pool_get_stats(struct page_pool *pool,
+/**
+ * page_pool_get_stats() - fetch page pool stats
+ * @pool: pool from which page was allocated
+ * @stats: struct page_pool_stats to fill in
+ *
+ * Retrieve statistics about the page_pool. This API is only available
+ * if the kernel has been configured with ``CONFIG_PAGE_POOL_STATS=y``.
+ * A pointer to a caller allocated struct page_pool_stats structure
+ * is passed to this API which is filled in. The caller can then report
+ * those stats to the user (perhaps via ethtool, debugfs, etc.).
+ */
+bool page_pool_get_stats(const struct page_pool *pool,
struct page_pool_stats *stats)
{
int cpu = 0;
@@ -107,9 +132,9 @@ int page_pool_ethtool_stats_get_count(void)
}
EXPORT_SYMBOL(page_pool_ethtool_stats_get_count);
-u64 *page_pool_ethtool_stats_get(u64 *data, void *stats)
+u64 *page_pool_ethtool_stats_get(u64 *data, const void *stats)
{
- struct page_pool_stats *pool_stats = stats;
+ const struct page_pool_stats *pool_stats = stats;
*data++ = pool_stats->alloc_stats.fast;
*data++ = pool_stats->alloc_stats.slow;
@@ -128,79 +153,189 @@ u64 *page_pool_ethtool_stats_get(u64 *data, 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)
+ __acquires(&pool->ring.producer_lock)
+{
+ bool in_softirq = in_softirq();
+
+ if (in_softirq)
+ spin_lock(&pool->ring.producer_lock);
+ else
+ spin_lock_bh(&pool->ring.producer_lock);
+
+ return in_softirq;
+}
+
+static void page_pool_producer_unlock(struct page_pool *pool,
+ bool in_softirq)
+ __releases(&pool->ring.producer_lock)
+{
+ if (in_softirq)
+ spin_unlock(&pool->ring.producer_lock);
+ else
+ spin_unlock_bh(&pool->ring.producer_lock);
+}
+
+static void page_pool_struct_check(void)
+{
+ CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_users);
+ CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_page);
+ CACHELINE_ASSERT_GROUP_MEMBER(struct page_pool, frag, frag_offset);
+ CACHELINE_ASSERT_GROUP_SIZE(struct page_pool, frag,
+ PAGE_POOL_FRAG_GROUP_ALIGN);
+}
+
static int page_pool_init(struct page_pool *pool,
- const struct page_pool_params *params)
+ const struct page_pool_params *params,
+ int cpuid)
{
unsigned int ring_qsize = 1024; /* Default */
+ struct netdev_rx_queue *rxq;
+ int err;
+
+ page_pool_struct_check();
- memcpy(&pool->p, params, sizeof(pool->p));
+ memcpy(&pool->p, &params->fast, sizeof(pool->p));
+ 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->p.flags & ~(PP_FLAG_ALL))
+ 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,
* which is the XDP_TX use-case.
*/
- if (pool->p.flags & PP_FLAG_DMA_MAP) {
+ if (pool->slow.flags & PP_FLAG_DMA_MAP) {
if ((pool->p.dma_dir != DMA_FROM_DEVICE) &&
(pool->p.dma_dir != DMA_BIDIRECTIONAL))
return -EINVAL;
+
+ pool->dma_map = true;
}
- if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) {
+ if (pool->slow.flags & PP_FLAG_DMA_SYNC_DEV) {
/* In order to request DMA-sync-for-device the page
* needs to be mapped
*/
- if (!(pool->p.flags & PP_FLAG_DMA_MAP))
+ if (!(pool->slow.flags & PP_FLAG_DMA_MAP))
return -EINVAL;
if (!pool->p.max_len)
return -EINVAL;
+ pool->dma_sync = true;
+
/* pool->p.offset has to be set according to the address
* offset used by the DMA engine to start copying rx data
*/
}
- if (PAGE_POOL_DMA_USE_PP_FRAG_COUNT &&
- pool->p.flags & PP_FLAG_PAGE_FRAG)
- return -EINVAL;
+ pool->has_init_callback = !!pool->slow.init_callback;
#ifdef CONFIG_PAGE_POOL_STATS
- pool->recycle_stats = alloc_percpu(struct page_pool_recycle_stats);
- if (!pool->recycle_stats)
- return -ENOMEM;
+ if (!(pool->slow.flags & PP_FLAG_SYSTEM_POOL)) {
+ pool->recycle_stats = alloc_percpu(struct page_pool_recycle_stats);
+ if (!pool->recycle_stats)
+ return -ENOMEM;
+ } else {
+ /* For system page pool instance we use a singular stats object
+ * instead of allocating a separate percpu variable for each
+ * (also percpu) page pool instance.
+ */
+ pool->recycle_stats = &pp_system_recycle_stats;
+ pool->system = true;
+ }
#endif
- if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0)
+ if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0) {
+#ifdef CONFIG_PAGE_POOL_STATS
+ if (!pool->system)
+ free_percpu(pool->recycle_stats);
+#endif
return -ENOMEM;
+ }
atomic_set(&pool->pages_state_release_cnt, 0);
/* Driver calling page_pool_create() also call page_pool_destroy() */
refcount_set(&pool->user_cnt, 1);
- if (pool->p.flags & PP_FLAG_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;
}
-struct page_pool *page_pool_create(const struct page_pool_params *params)
+static void page_pool_uninit(struct page_pool *pool)
+{
+ 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
+}
+
+/**
+ * page_pool_create_percpu() - create a page pool for a given cpu.
+ * @params: parameters, see struct page_pool_params
+ * @cpuid: cpu identifier
+ */
+struct page_pool *
+page_pool_create_percpu(const struct page_pool_params *params, int cpuid)
{
struct page_pool *pool;
int err;
@@ -209,30 +344,47 @@ struct page_pool *page_pool_create(const struct page_pool_params *params)
if (!pool)
return ERR_PTR(-ENOMEM);
- err = page_pool_init(pool, params);
- if (err < 0) {
- pr_warn("%s() gave up with errno %d\n", __func__, err);
- kfree(pool);
- return ERR_PTR(err);
- }
+ err = page_pool_init(pool, params, cpuid);
+ if (err < 0)
+ goto err_free;
+
+ err = page_pool_list(pool);
+ if (err)
+ goto err_uninit;
return pool;
+
+err_uninit:
+ page_pool_uninit(pool);
+err_free:
+ pr_warn("%s() gave up with errno %d\n", __func__, err);
+ kfree(pool);
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(page_pool_create_percpu);
+
+/**
+ * page_pool_create() - create a page pool
+ * @params: parameters, see struct page_pool_params
+ */
+struct page_pool *page_pool_create(const struct page_pool_params *params)
+{
+ return page_pool_create_percpu(params, -1);
}
EXPORT_SYMBOL(page_pool_create);
-static void page_pool_return_page(struct page_pool *pool, struct page *page);
+static void page_pool_return_netmem(struct page_pool *pool, netmem_ref netmem);
-noinline
-static struct page *page_pool_refill_alloc_cache(struct page_pool *pool)
+static noinline netmem_ref page_pool_refill_alloc_cache(struct page_pool *pool)
{
struct ptr_ring *r = &pool->ring;
- struct page *page;
+ netmem_ref netmem;
int pref_nid; /* preferred NUMA node */
/* Quicker fallback, avoid locks when ring is empty */
if (__ptr_ring_empty(r)) {
alloc_stat_inc(pool, empty);
- return NULL;
+ return 0;
}
/* Softirq guarantee CPU and thus NUMA node is stable. This,
@@ -247,99 +399,166 @@ static struct page *page_pool_refill_alloc_cache(struct page_pool *pool)
/* Refill alloc array, but only if NUMA match */
do {
- page = __ptr_ring_consume(r);
- if (unlikely(!page))
+ netmem = (__force netmem_ref)__ptr_ring_consume(r);
+ if (unlikely(!netmem))
break;
- if (likely(page_to_nid(page) == pref_nid)) {
- pool->alloc.cache[pool->alloc.count++] = page;
+ if (likely(netmem_is_pref_nid(netmem, pref_nid))) {
+ pool->alloc.cache[pool->alloc.count++] = netmem;
} else {
/* NUMA mismatch;
* (1) release 1 page to page-allocator and
* (2) break out to fallthrough to alloc_pages_node.
* This limit stress on page buddy alloactor.
*/
- page_pool_return_page(pool, page);
+ page_pool_return_netmem(pool, netmem);
alloc_stat_inc(pool, waive);
- page = NULL;
+ netmem = 0;
break;
}
} while (pool->alloc.count < PP_ALLOC_CACHE_REFILL);
/* Return last page */
if (likely(pool->alloc.count > 0)) {
- page = pool->alloc.cache[--pool->alloc.count];
+ netmem = pool->alloc.cache[--pool->alloc.count];
alloc_stat_inc(pool, refill);
}
- return page;
+ return netmem;
}
/* fast path */
-static struct page *__page_pool_get_cached(struct page_pool *pool)
+static netmem_ref __page_pool_get_cached(struct page_pool *pool)
{
- struct page *page;
+ netmem_ref netmem;
/* Caller MUST guarantee safe non-concurrent access, e.g. softirq */
if (likely(pool->alloc.count)) {
/* Fast-path */
- page = pool->alloc.cache[--pool->alloc.count];
+ netmem = pool->alloc.cache[--pool->alloc.count];
alloc_stat_inc(pool, fast);
} else {
- page = page_pool_refill_alloc_cache(pool);
+ netmem = page_pool_refill_alloc_cache(pool);
}
- return page;
+ return netmem;
}
-static void page_pool_dma_sync_for_device(struct page_pool *pool,
- struct page *page,
- unsigned int dma_sync_size)
+static void __page_pool_dma_sync_for_device(const struct page_pool *pool,
+ netmem_ref netmem,
+ u32 dma_sync_size)
{
- dma_addr_t dma_addr = page_pool_get_dma_addr(page);
+#if defined(CONFIG_HAS_DMA) && defined(CONFIG_DMA_NEED_SYNC)
+ dma_addr_t dma_addr = page_pool_get_dma_addr_netmem(netmem);
dma_sync_size = min(dma_sync_size, pool->p.max_len);
- dma_sync_single_range_for_device(pool->p.dev, dma_addr,
- pool->p.offset, dma_sync_size,
- pool->p.dma_dir);
+ __dma_sync_single_for_device(pool->p.dev, dma_addr + pool->p.offset,
+ dma_sync_size, pool->p.dma_dir);
+#endif
}
-static bool page_pool_dma_map(struct page_pool *pool, struct page *page)
+static __always_inline void
+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)) {
+ 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, 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
* into page private data (i.e 32bit cpu with 64bit DMA caps)
* This mapping is kept for lifetime of page, until leaving pool.
*/
- dma = dma_map_page_attrs(pool->p.dev, page, 0,
- (PAGE_SIZE << pool->p.order),
- pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC);
+ dma = dma_map_page_attrs(pool->p.dev, netmem_to_page(netmem), 0,
+ (PAGE_SIZE << pool->p.order), pool->p.dma_dir,
+ DMA_ATTR_SKIP_CPU_SYNC |
+ DMA_ATTR_WEAK_ORDERING);
if (dma_mapping_error(pool->p.dev, dma))
return false;
- page_pool_set_dma_addr(page, dma);
+ if (page_pool_set_dma_addr_netmem(netmem, dma)) {
+ WARN_ONCE(1, "unexpected DMA address, please report to netdev@");
+ goto unmap_failed;
+ }
- if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
- page_pool_dma_sync_for_device(pool, page, pool->p.max_len);
+ err = page_pool_register_dma_index(pool, netmem, gfp);
+ if (err)
+ goto unset_failed;
- return true;
-}
+ page_pool_dma_sync_for_device(pool, netmem, pool->p.max_len);
-static void page_pool_set_pp_info(struct page_pool *pool,
- struct page *page)
-{
- page->pp = pool;
- page->pp_magic |= PP_SIGNATURE;
- if (pool->p.init_callback)
- pool->p.init_callback(page, pool->p.init_arg);
-}
+ return true;
-static void page_pool_clear_pp_info(struct page *page)
-{
- page->pp_magic = 0;
- page->pp = NULL;
+unset_failed:
+ page_pool_set_dma_addr_netmem(netmem, 0);
+unmap_failed:
+ 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 struct page *__page_pool_alloc_page_order(struct page_pool *pool,
@@ -352,94 +571,108 @@ static struct page *__page_pool_alloc_page_order(struct page_pool *pool,
if (unlikely(!page))
return NULL;
- if ((pool->p.flags & PP_FLAG_DMA_MAP) &&
- unlikely(!page_pool_dma_map(pool, page))) {
+ if (pool->dma_map && unlikely(!page_pool_dma_map(pool, page_to_netmem(page), gfp))) {
put_page(page);
return NULL;
}
alloc_stat_inc(pool, slow_high_order);
- page_pool_set_pp_info(pool, page);
+ page_pool_set_pp_info(pool, page_to_netmem(page));
/* Track how many pages are held 'in-flight' */
pool->pages_state_hold_cnt++;
- trace_page_pool_state_hold(pool, page, pool->pages_state_hold_cnt);
+ trace_page_pool_state_hold(pool, page_to_netmem(page),
+ pool->pages_state_hold_cnt);
return page;
}
/* slow path */
-noinline
-static struct page *__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_flags = pool->p.flags;
unsigned int pp_order = pool->p.order;
- struct page *page;
+ bool dma_map = pool->dma_map;
+ 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_pool_alloc_page_order(pool, gfp);
+ return page_to_netmem(__page_pool_alloc_page_order(pool, gfp));
/* Unnecessary as alloc cache is empty, but guarantees zero count */
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,
- pool->alloc.cache);
+ nr_pages = alloc_pages_bulk_node(gfp, pool->p.nid, bulk,
+ (struct page **)pool->alloc.cache);
if (unlikely(!nr_pages))
- return NULL;
+ return 0;
/* Pages have been filled into alloc.cache array, but count is zero and
* page element have not been (possibly) DMA mapped.
*/
for (i = 0; i < nr_pages; i++) {
- page = pool->alloc.cache[i];
- if ((pp_flags & PP_FLAG_DMA_MAP) &&
- unlikely(!page_pool_dma_map(pool, page))) {
- put_page(page);
+ netmem = pool->alloc.cache[i];
+ if (dma_map && unlikely(!page_pool_dma_map(pool, netmem, gfp))) {
+ put_page(netmem_to_page(netmem));
continue;
}
- page_pool_set_pp_info(pool, page);
- pool->alloc.cache[pool->alloc.count++] = page;
+ page_pool_set_pp_info(pool, netmem);
+ pool->alloc.cache[pool->alloc.count++] = netmem;
/* Track how many pages are held 'in-flight' */
pool->pages_state_hold_cnt++;
- trace_page_pool_state_hold(pool, page,
+ trace_page_pool_state_hold(pool, netmem,
pool->pages_state_hold_cnt);
}
/* Return last page */
if (likely(pool->alloc.count > 0)) {
- page = pool->alloc.cache[--pool->alloc.count];
+ netmem = pool->alloc.cache[--pool->alloc.count];
alloc_stat_inc(pool, slow);
} else {
- page = NULL;
+ netmem = 0;
}
/* When page just alloc'ed is should/must have refcnt 1. */
- return page;
+ return netmem;
}
/* For using page_pool replace: alloc_pages() API calls, but provide
* synchronization guarantee for allocation side.
*/
-struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp)
+netmem_ref page_pool_alloc_netmems(struct page_pool *pool, gfp_t gfp)
{
- struct page *page;
+ netmem_ref netmem;
/* Fast-path: Get a page from cache */
- page = __page_pool_get_cached(pool);
- if (page)
- return page;
+ netmem = __page_pool_get_cached(pool);
+ if (netmem)
+ return netmem;
/* Slow-path: cache empty, do real allocation */
- page = __page_pool_alloc_pages_slow(pool, gfp);
- return page;
+ 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_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_netmems(pool, gfp));
}
EXPORT_SYMBOL(page_pool_alloc_pages);
@@ -448,7 +681,7 @@ EXPORT_SYMBOL(page_pool_alloc_pages);
*/
#define _distance(a, b) (s32)((a) - (b))
-static s32 page_pool_inflight(struct page_pool *pool)
+s32 page_pool_inflight(const struct page_pool *pool, bool strict)
{
u32 release_cnt = atomic_read(&pool->pages_state_release_cnt);
u32 hold_cnt = READ_ONCE(pool->pages_state_hold_cnt);
@@ -456,73 +689,106 @@ static s32 page_pool_inflight(struct page_pool *pool)
inflight = _distance(hold_cnt, release_cnt);
- trace_page_pool_release(pool, inflight, hold_cnt, release_cnt);
- WARN(inflight < 0, "Negative(%d) inflight packet-pages", inflight);
+ if (strict) {
+ trace_page_pool_release(pool, inflight, hold_cnt, release_cnt);
+ WARN(inflight < 0, "Negative(%d) inflight packet-pages",
+ inflight);
+ } else {
+ inflight = max(0, inflight);
+ }
return inflight;
}
-/* Disconnects a page (from a page_pool). API users can have a need
- * to disconnect a page (from a page_pool), to allow it to be used as
- * a regular page (that will eventually be returned to the normal
- * page-allocator via put_page).
- */
-void page_pool_release_page(struct page_pool *pool, struct page *page)
+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;
- int count;
- if (!(pool->p.flags & PP_FLAG_DMA_MAP))
+ if (!pool->dma_map)
/* Always account for inflight pages, even if we didn't
* map them
*/
- goto skip_dma_unmap;
+ return;
+
+ if (page_pool_release_dma_index(pool, netmem))
+ return;
- dma = page_pool_get_dma_addr(page);
+ dma = page_pool_get_dma_addr_netmem(netmem);
/* When page is unmapped, it cannot be returned to our pool */
dma_unmap_page_attrs(pool->p.dev, dma,
PAGE_SIZE << pool->p.order, pool->p.dma_dir,
- DMA_ATTR_SKIP_CPU_SYNC);
- page_pool_set_dma_addr(page, 0);
-skip_dma_unmap:
- page_pool_clear_pp_info(page);
+ DMA_ATTR_SKIP_CPU_SYNC | DMA_ATTR_WEAK_ORDERING);
+ page_pool_set_dma_addr_netmem(netmem, 0);
+}
+
+/* Disconnects a page (from a page_pool). API users can have a need
+ * to disconnect a page (from a page_pool), to allow it to be used as
+ * a regular page (that will eventually be returned to the normal
+ * page-allocator via put_page).
+ */
+static void page_pool_return_netmem(struct page_pool *pool, netmem_ref netmem)
+{
+ int count;
+ bool put;
+
+ 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.
*/
count = atomic_inc_return_relaxed(&pool->pages_state_release_cnt);
- trace_page_pool_state_release(pool, page, count);
-}
-EXPORT_SYMBOL(page_pool_release_page);
+ trace_page_pool_state_release(pool, netmem, count);
-/* Return a page to the page allocator, cleaning up our state */
-static void page_pool_return_page(struct page_pool *pool, struct page *page)
-{
- page_pool_release_page(pool, page);
-
- put_page(page);
+ 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).
*/
}
-static bool page_pool_recycle_in_ring(struct page_pool *pool, struct page *page)
+static bool page_pool_recycle_in_ring(struct page_pool *pool, netmem_ref netmem)
{
- int ret;
- /* BH protection not needed if current is serving softirq */
- if (in_serving_softirq())
- ret = ptr_ring_produce(&pool->ring, page);
- else
- ret = ptr_ring_produce_bh(&pool->ring, page);
+ 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
@@ -530,7 +796,7 @@ static bool page_pool_recycle_in_ring(struct page_pool *pool, struct page *page)
*
* Caller must provide appropriate safe context.
*/
-static bool page_pool_recycle_in_cache(struct page *page,
+static bool page_pool_recycle_in_cache(netmem_ref netmem,
struct page_pool *pool)
{
if (unlikely(pool->alloc.count == PP_ALLOC_CACHE_SIZE)) {
@@ -539,21 +805,30 @@ static bool page_pool_recycle_in_cache(struct page *page,
}
/* Caller MUST have verified/know (page_ref_count(page) == 1) */
- pool->alloc.cache[pool->alloc.count++] = page;
+ pool->alloc.cache[pool->alloc.count++] = netmem;
recycle_stat_inc(pool, cached);
return true;
}
+static bool __page_pool_page_can_be_recycled(netmem_ref 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.
- * if PP_FLAG_DMA_SYNC_DEV is set, we'll try to sync the DMA area for
+ * If pool->dma_sync is set, we'll try to sync the DMA area for
* the configured size min(dma_sync_size, pool->max_len).
* If the page refcnt != 1, then the page will be returned to memory
* subsystem.
*/
-static __always_inline struct page *
-__page_pool_put_page(struct page_pool *pool, struct page *page,
+static __always_inline netmem_ref
+__page_pool_put_page(struct page_pool *pool, netmem_ref netmem,
unsigned int dma_sync_size, bool allow_direct)
{
+ lockdep_assert_no_hardirq();
+
/* This allocator is optimized for the XDP mode that uses
* one-frame-per-page, but have fallbacks that act like the
* regular page allocator APIs.
@@ -563,20 +838,18 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
* page is NOT reusable when allocated when system is under
* some pressure. (page_is_pfmemalloc)
*/
- if (likely(page_ref_count(page) == 1 && !page_is_pfmemalloc(page))) {
+ if (likely(__page_pool_page_can_be_recycled(netmem))) {
/* Read barrier done in page_ref_count / READ_ONCE */
- if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
- page_pool_dma_sync_for_device(pool, page,
- dma_sync_size);
+ page_pool_dma_sync_for_device(pool, netmem, dma_sync_size);
- if (allow_direct && in_serving_softirq() &&
- page_pool_recycle_in_cache(page, pool))
- return NULL;
+ if (allow_direct && page_pool_recycle_in_cache(netmem, pool))
+ return 0;
/* Page found as candidate for recycling */
- return page;
+ return netmem;
}
+
/* Fallback/non-XDP mode: API user have elevated refcnt.
*
* Many drivers split up the page into fragments, and some
@@ -591,184 +864,279 @@ __page_pool_put_page(struct page_pool *pool, struct page *page,
* will be invoking put_page.
*/
recycle_stat_inc(pool, released_refcnt);
- /* Do not replace this with page_pool_return_page() */
- page_pool_release_page(pool, page);
- put_page(page);
+ page_pool_return_netmem(pool, netmem);
- return NULL;
+ return 0;
}
-void page_pool_put_defragged_page(struct page_pool *pool, struct page *page,
+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;
+
+ /* Allow direct recycle if we have reasons to believe that we are
+ * in the same context as the consumer would run, so there's
+ * no possible race.
+ * __page_pool_put_page() makes sure we're not in hardirq context
+ * and interrupts are enabled prior to accessing the cache.
+ */
+ cpuid = smp_processor_id();
+ if (READ_ONCE(pool->cpuid) == cpuid)
+ return true;
+
+ napi = READ_ONCE(pool->p.napi);
+
+ return napi && READ_ONCE(napi->list_owner) == cpuid;
+}
+
+void page_pool_put_unrefed_netmem(struct page_pool *pool, netmem_ref netmem,
unsigned int dma_sync_size, bool allow_direct)
{
- page = __page_pool_put_page(pool, page, dma_sync_size, allow_direct);
- if (page && !page_pool_recycle_in_ring(pool, page)) {
+ if (!allow_direct)
+ allow_direct = page_pool_napi_local(pool);
+
+ 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, page);
+ page_pool_return_netmem(pool, netmem);
}
}
-EXPORT_SYMBOL(page_pool_put_defragged_page);
+EXPORT_SYMBOL(page_pool_put_unrefed_netmem);
-/* Caller must not use data area after call, as this function overwrites it */
-void page_pool_put_page_bulk(struct page_pool *pool, void **data,
- int count)
+void page_pool_put_unrefed_page(struct page_pool *pool, struct page *page,
+ unsigned int dma_sync_size, bool allow_direct)
{
- int i, bulk_len = 0;
-
- for (i = 0; i < count; i++) {
- struct page *page = virt_to_head_page(data[i]);
-
- /* It is not the last user for the page frag case */
- if (!page_pool_is_last_frag(pool, page))
- continue;
+ page_pool_put_unrefed_netmem(pool, page_to_netmem(page), dma_sync_size,
+ allow_direct);
+}
+EXPORT_SYMBOL(page_pool_put_unrefed_page);
- page = __page_pool_put_page(pool, page, -1, false);
- /* Approved for bulk recycling in ptr_ring cache */
- if (page)
- data[bulk_len++] = page;
- }
+static void page_pool_recycle_ring_bulk(struct page_pool *pool,
+ netmem_ref *bulk,
+ u32 bulk_len)
+{
+ bool in_softirq;
+ u32 i;
- if (unlikely(!bulk_len))
- return;
+ /* Bulk produce into ptr_ring page_pool cache */
+ in_softirq = page_pool_producer_lock(pool);
- /* Bulk producer into ptr_ring page_pool cache */
- page_pool_ring_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;
}
}
+
+ page_pool_producer_unlock(pool, in_softirq);
recycle_stat_add(pool, ring, i);
- page_pool_ring_unlock(pool);
- /* 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, data[i]);
+ page_pool_return_netmem(pool, bulk[i]);
}
-EXPORT_SYMBOL(page_pool_put_page_bulk);
-static struct page *page_pool_drain_frag(struct page_pool *pool,
- struct page *page)
+/**
+ * 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_netmem_bulk);
+
+static netmem_ref page_pool_drain_frag(struct page_pool *pool,
+ netmem_ref netmem)
{
long drain_count = BIAS_MAX - pool->frag_users;
/* Some user is still using the page frag */
- if (likely(page_pool_defrag_page(page, drain_count)))
- return NULL;
-
- if (page_ref_count(page) == 1 && !page_is_pfmemalloc(page)) {
- if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV)
- page_pool_dma_sync_for_device(pool, page, -1);
+ if (likely(page_pool_unref_netmem(netmem, drain_count)))
+ return 0;
- return page;
+ if (__page_pool_page_can_be_recycled(netmem)) {
+ page_pool_dma_sync_for_device(pool, netmem, -1);
+ return netmem;
}
- page_pool_return_page(pool, page);
- return NULL;
+ page_pool_return_netmem(pool, netmem);
+ return 0;
}
static void page_pool_free_frag(struct page_pool *pool)
{
long drain_count = BIAS_MAX - pool->frag_users;
- struct page *page = pool->frag_page;
+ netmem_ref netmem = pool->frag_page;
- pool->frag_page = NULL;
+ pool->frag_page = 0;
- if (!page || page_pool_defrag_page(page, drain_count))
+ if (!netmem || page_pool_unref_netmem(netmem, drain_count))
return;
- page_pool_return_page(pool, page);
+ page_pool_return_netmem(pool, netmem);
}
-struct page *page_pool_alloc_frag(struct page_pool *pool,
- unsigned int *offset,
- unsigned int size, gfp_t gfp)
+netmem_ref page_pool_alloc_frag_netmem(struct page_pool *pool,
+ unsigned int *offset, unsigned int size,
+ gfp_t gfp)
{
unsigned int max_size = PAGE_SIZE << pool->p.order;
- struct page *page = pool->frag_page;
+ netmem_ref netmem = pool->frag_page;
- if (WARN_ON(!(pool->p.flags & PP_FLAG_PAGE_FRAG) ||
- size > max_size))
- return NULL;
+ if (WARN_ON(size > max_size))
+ return 0;
size = ALIGN(size, dma_get_cache_alignment());
*offset = pool->frag_offset;
- if (page && *offset + size > max_size) {
- page = page_pool_drain_frag(pool, page);
- if (page) {
+ 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 (!page) {
- page = page_pool_alloc_pages(pool, gfp);
- if (unlikely(!page)) {
- pool->frag_page = NULL;
- return NULL;
+ if (!netmem) {
+ netmem = page_pool_alloc_netmems(pool, gfp);
+ if (unlikely(!netmem)) {
+ pool->frag_page = 0;
+ return 0;
}
- pool->frag_page = page;
+ pool->frag_page = netmem;
frag_reset:
pool->frag_users = 1;
*offset = 0;
pool->frag_offset = size;
- page_pool_fragment_page(page, BIAS_MAX);
- return page;
+ page_pool_fragment_netmem(netmem, BIAS_MAX);
+ return netmem;
}
pool->frag_users++;
pool->frag_offset = *offset + size;
- alloc_stat_inc(pool, fast);
- return page;
+ return netmem;
+}
+EXPORT_SYMBOL(page_pool_alloc_frag_netmem);
+
+struct page *page_pool_alloc_frag(struct page_pool *pool, unsigned int *offset,
+ unsigned int size, gfp_t gfp)
+{
+ return netmem_to_page(page_pool_alloc_frag_netmem(pool, offset, size,
+ gfp));
}
EXPORT_SYMBOL(page_pool_alloc_frag);
static void page_pool_empty_ring(struct page_pool *pool)
{
- struct page *page;
+ netmem_ref netmem;
/* Empty recycle ring */
- while ((page = ptr_ring_consume_bh(&pool->ring))) {
+ while ((netmem = (__force netmem_ref)ptr_ring_consume_bh(&pool->ring))) {
/* Verify the refcnt invariant of cached pages */
- if (!(page_ref_count(page) == 1))
+ if (!(netmem_ref_count(netmem) == 1))
pr_crit("%s() page_pool refcnt %d violation\n",
- __func__, page_ref_count(page));
+ __func__, netmem_ref_count(netmem));
- page_pool_return_page(pool, page);
+ page_pool_return_netmem(pool, netmem);
}
}
-static void page_pool_free(struct page_pool *pool)
+static void __page_pool_destroy(struct page_pool *pool)
{
if (pool->disconnect)
pool->disconnect(pool);
- ptr_ring_cleanup(&pool->ring, NULL);
+ page_pool_unlist(pool);
+ page_pool_uninit(pool);
- if (pool->p.flags & PP_FLAG_DMA_MAP)
- put_device(pool->p.dev);
+ if (pool->mp_ops) {
+ pool->mp_ops->destroy(pool);
+ static_branch_dec(&page_pool_mem_providers);
+ }
-#ifdef CONFIG_PAGE_POOL_STATS
- free_percpu(pool->recycle_stats);
-#endif
kfree(pool);
}
static void page_pool_empty_alloc_cache_once(struct page_pool *pool)
{
- struct page *page;
+ netmem_ref netmem;
if (pool->destroy_cnt)
return;
@@ -778,15 +1146,36 @@ static void page_pool_empty_alloc_cache_once(struct page_pool *pool)
* call concurrently.
*/
while (pool->alloc.count) {
- page = pool->alloc.cache[--pool->alloc.count];
- page_pool_return_page(pool, page);
+ netmem = pool->alloc.cache[--pool->alloc.count];
+ 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.
@@ -796,12 +1185,16 @@ 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);
+ 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_free(pool);
+ __page_pool_destroy(pool);
return inflight;
}
@@ -810,18 +1203,27 @@ static void page_pool_release_retry(struct work_struct *wq)
{
struct delayed_work *dwq = to_delayed_work(wq);
struct page_pool *pool = container_of(dwq, typeof(*pool), release_dw);
+ void *netdev;
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 */
- if (time_after_eq(jiffies, pool->defer_warn)) {
+ /* Periodic warning for page pools the user can't see */
+ netdev = READ_ONCE(pool->slow.netdev);
+ if (time_after_eq(jiffies, pool->defer_warn) &&
+ (!netdev || netdev == NET_PTR_POISON)) {
int sec = (s32)((u32)jiffies - (u32)pool->defer_start) / HZ;
- pr_warn("%s() stalled pool shutdown %d inflight %d sec\n",
- __func__, inflight, sec);
+ pr_warn("%s() stalled pool shutdown: id %u, %d inflight %d sec\n",
+ __func__, pool->user.id, inflight, sec);
pool->defer_warn = jiffies + DEFER_WARN_INTERVAL;
}
@@ -830,13 +1232,60 @@ static void page_pool_release_retry(struct work_struct *wq)
}
void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *),
- struct xdp_mem_info *mem)
+ const struct xdp_mem_info *mem)
{
refcount_inc(&pool->user_cnt);
pool->disconnect = disconnect;
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.
+ * Paired with READ_ONCE() in page_pool_napi_local().
+ */
+ WRITE_ONCE(pool->cpuid, -1);
+
+ if (!pool->p.napi)
+ return;
+
+ 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);
+
void page_pool_destroy(struct page_pool *pool)
{
if (!pool)
@@ -845,11 +1294,13 @@ void page_pool_destroy(struct page_pool *pool)
if (!page_pool_put(pool))
return;
+ page_pool_disable_direct_recycling(pool);
page_pool_free_frag(pool);
if (!page_pool_release(pool))
return;
+ page_pool_detached(pool);
pool->defer_start = jiffies;
pool->defer_warn = jiffies + DEFER_WARN_INTERVAL;
@@ -861,44 +1312,43 @@ EXPORT_SYMBOL(page_pool_destroy);
/* Caller must provide appropriate safe context, e.g. NAPI. */
void page_pool_update_nid(struct page_pool *pool, int new_nid)
{
- struct page *page;
+ netmem_ref netmem;
trace_page_pool_update_nid(pool, new_nid);
pool->p.nid = new_nid;
/* Flush pool alloc cache, as refill will check NUMA node */
while (pool->alloc.count) {
- page = pool->alloc.cache[--pool->alloc.count];
- page_pool_return_page(pool, page);
+ netmem = pool->alloc.cache[--pool->alloc.count];
+ page_pool_return_netmem(pool, netmem);
}
}
EXPORT_SYMBOL(page_pool_update_nid);
-bool page_pool_return_skb_page(struct page *page)
+bool net_mp_niov_set_dma_addr(struct net_iov *niov, dma_addr_t addr)
{
- struct page_pool *pp;
+ return page_pool_set_dma_addr_netmem(net_iov_to_netmem(niov), addr);
+}
- page = compound_head(page);
+/* 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->pp_magic is OR'ed with PP_SIGNATURE after the allocation
- * in order to preserve any existing bits, such as bit 0 for the
- * head page of compound page and bit 1 for pfmemalloc page, so
- * mask those bits for freeing side when doing below checking,
- * and page_is_pfmemalloc() is checked in __page_pool_put_page()
- * to avoid recycling the pfmemalloc page.
- */
- if (unlikely((page->pp_magic & ~0x3UL) != PP_SIGNATURE))
- return false;
+ page_pool_set_pp_info(pool, netmem);
- pp = page->pp;
+ pool->pages_state_hold_cnt++;
+ trace_page_pool_state_hold(pool, netmem, pool->pages_state_hold_cnt);
+}
- /* Driver set this to memory recycling info. Reset it on recycle.
- * This will *not* work for NIC using a split-page memory model.
- * The page will be returned to the pool here regardless of the
- * 'flipped' fragment being in use or not.
- */
- page_pool_put_full_page(pp, page, false);
+/* 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);
- return true;
+ page_pool_clear_pp_info(netmem);
}
-EXPORT_SYMBOL(page_pool_return_skb_page);