Commit | Line | Data |
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ff7d6b27 JDB |
1 | /* SPDX-License-Identifier: GPL-2.0 |
2 | * | |
3 | * page_pool.c | |
4 | * Author: Jesper Dangaard Brouer <netoptimizer@brouer.com> | |
5 | * Copyright (C) 2016 Red Hat, Inc. | |
6 | */ | |
32c28f7e | 7 | |
ff7d6b27 JDB |
8 | #include <linux/types.h> |
9 | #include <linux/kernel.h> | |
10 | #include <linux/slab.h> | |
f71fec47 | 11 | #include <linux/device.h> |
ff7d6b27 JDB |
12 | |
13 | #include <net/page_pool.h> | |
14 | #include <linux/dma-direction.h> | |
15 | #include <linux/dma-mapping.h> | |
16 | #include <linux/page-flags.h> | |
17 | #include <linux/mm.h> /* for __put_page() */ | |
18 | ||
32c28f7e JDB |
19 | #include <trace/events/page_pool.h> |
20 | ||
c3f812ce JL |
21 | #define DEFER_TIME (msecs_to_jiffies(1000)) |
22 | #define DEFER_WARN_INTERVAL (60 * HZ) | |
23 | ||
ff7d6b27 JDB |
24 | static int page_pool_init(struct page_pool *pool, |
25 | const struct page_pool_params *params) | |
26 | { | |
27 | unsigned int ring_qsize = 1024; /* Default */ | |
28 | ||
29 | memcpy(&pool->p, params, sizeof(pool->p)); | |
30 | ||
31 | /* Validate only known flags were used */ | |
32 | if (pool->p.flags & ~(PP_FLAG_ALL)) | |
33 | return -EINVAL; | |
34 | ||
35 | if (pool->p.pool_size) | |
36 | ring_qsize = pool->p.pool_size; | |
37 | ||
38 | /* Sanity limit mem that can be pinned down */ | |
39 | if (ring_qsize > 32768) | |
40 | return -E2BIG; | |
41 | ||
42 | /* DMA direction is either DMA_FROM_DEVICE or DMA_BIDIRECTIONAL. | |
43 | * DMA_BIDIRECTIONAL is for allowing page used for DMA sending, | |
44 | * which is the XDP_TX use-case. | |
45 | */ | |
46 | if ((pool->p.dma_dir != DMA_FROM_DEVICE) && | |
47 | (pool->p.dma_dir != DMA_BIDIRECTIONAL)) | |
48 | return -EINVAL; | |
49 | ||
e68bc756 LB |
50 | if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) { |
51 | /* In order to request DMA-sync-for-device the page | |
52 | * needs to be mapped | |
53 | */ | |
54 | if (!(pool->p.flags & PP_FLAG_DMA_MAP)) | |
55 | return -EINVAL; | |
56 | ||
57 | if (!pool->p.max_len) | |
58 | return -EINVAL; | |
59 | ||
60 | /* pool->p.offset has to be set according to the address | |
61 | * offset used by the DMA engine to start copying rx data | |
62 | */ | |
63 | } | |
64 | ||
ff7d6b27 JDB |
65 | if (ptr_ring_init(&pool->ring, ring_qsize, GFP_KERNEL) < 0) |
66 | return -ENOMEM; | |
67 | ||
99c07c43 JDB |
68 | atomic_set(&pool->pages_state_release_cnt, 0); |
69 | ||
1da4bbef IK |
70 | /* Driver calling page_pool_create() also call page_pool_destroy() */ |
71 | refcount_set(&pool->user_cnt, 1); | |
72 | ||
f71fec47 JDB |
73 | if (pool->p.flags & PP_FLAG_DMA_MAP) |
74 | get_device(pool->p.dev); | |
75 | ||
ff7d6b27 JDB |
76 | return 0; |
77 | } | |
78 | ||
79 | struct page_pool *page_pool_create(const struct page_pool_params *params) | |
80 | { | |
81 | struct page_pool *pool; | |
873343e7 | 82 | int err; |
ff7d6b27 JDB |
83 | |
84 | pool = kzalloc_node(sizeof(*pool), GFP_KERNEL, params->nid); | |
85 | if (!pool) | |
86 | return ERR_PTR(-ENOMEM); | |
87 | ||
88 | err = page_pool_init(pool, params); | |
89 | if (err < 0) { | |
90 | pr_warn("%s() gave up with errno %d\n", __func__, err); | |
91 | kfree(pool); | |
92 | return ERR_PTR(err); | |
93 | } | |
1da4bbef | 94 | |
ff7d6b27 JDB |
95 | return pool; |
96 | } | |
97 | EXPORT_SYMBOL(page_pool_create); | |
98 | ||
44768dec JDB |
99 | static void __page_pool_return_page(struct page_pool *pool, struct page *page); |
100 | ||
101 | noinline | |
102 | static struct page *page_pool_refill_alloc_cache(struct page_pool *pool, | |
103 | bool refill) | |
104 | { | |
105 | struct ptr_ring *r = &pool->ring; | |
106 | struct page *page; | |
107 | int pref_nid; /* preferred NUMA node */ | |
108 | ||
109 | /* Quicker fallback, avoid locks when ring is empty */ | |
110 | if (__ptr_ring_empty(r)) | |
111 | return NULL; | |
112 | ||
113 | /* Softirq guarantee CPU and thus NUMA node is stable. This, | |
114 | * assumes CPU refilling driver RX-ring will also run RX-NAPI. | |
115 | */ | |
116 | pref_nid = (pool->p.nid == NUMA_NO_NODE) ? numa_mem_id() : pool->p.nid; | |
117 | ||
118 | /* Slower-path: Get pages from locked ring queue */ | |
119 | spin_lock(&r->consumer_lock); | |
120 | ||
121 | /* Refill alloc array, but only if NUMA match */ | |
122 | do { | |
123 | page = __ptr_ring_consume(r); | |
124 | if (unlikely(!page)) | |
125 | break; | |
126 | ||
127 | if (likely(page_to_nid(page) == pref_nid)) { | |
128 | pool->alloc.cache[pool->alloc.count++] = page; | |
129 | } else { | |
130 | /* NUMA mismatch; | |
131 | * (1) release 1 page to page-allocator and | |
132 | * (2) break out to fallthrough to alloc_pages_node. | |
133 | * This limit stress on page buddy alloactor. | |
134 | */ | |
135 | __page_pool_return_page(pool, page); | |
136 | page = NULL; | |
137 | break; | |
138 | } | |
139 | } while (pool->alloc.count < PP_ALLOC_CACHE_REFILL && | |
140 | refill); | |
141 | ||
142 | /* Return last page */ | |
143 | if (likely(pool->alloc.count > 0)) | |
144 | page = pool->alloc.cache[--pool->alloc.count]; | |
145 | ||
146 | spin_unlock(&r->consumer_lock); | |
147 | return page; | |
148 | } | |
149 | ||
ff7d6b27 JDB |
150 | /* fast path */ |
151 | static struct page *__page_pool_get_cached(struct page_pool *pool) | |
152 | { | |
8d73f8f2 | 153 | bool refill = false; |
ff7d6b27 JDB |
154 | struct page *page; |
155 | ||
ff7d6b27 JDB |
156 | /* Test for safe-context, caller should provide this guarantee */ |
157 | if (likely(in_serving_softirq())) { | |
158 | if (likely(pool->alloc.count)) { | |
159 | /* Fast-path */ | |
160 | page = pool->alloc.cache[--pool->alloc.count]; | |
161 | return page; | |
162 | } | |
8d73f8f2 | 163 | refill = true; |
ff7d6b27 JDB |
164 | } |
165 | ||
44768dec | 166 | page = page_pool_refill_alloc_cache(pool, refill); |
ff7d6b27 JDB |
167 | return page; |
168 | } | |
169 | ||
e68bc756 LB |
170 | static void page_pool_dma_sync_for_device(struct page_pool *pool, |
171 | struct page *page, | |
172 | unsigned int dma_sync_size) | |
173 | { | |
174 | dma_sync_size = min(dma_sync_size, pool->p.max_len); | |
175 | dma_sync_single_range_for_device(pool->p.dev, page->dma_addr, | |
176 | pool->p.offset, dma_sync_size, | |
177 | pool->p.dma_dir); | |
178 | } | |
179 | ||
ff7d6b27 JDB |
180 | /* slow path */ |
181 | noinline | |
182 | static struct page *__page_pool_alloc_pages_slow(struct page_pool *pool, | |
183 | gfp_t _gfp) | |
184 | { | |
185 | struct page *page; | |
186 | gfp_t gfp = _gfp; | |
187 | dma_addr_t dma; | |
188 | ||
189 | /* We could always set __GFP_COMP, and avoid this branch, as | |
190 | * prep_new_page() can handle order-0 with __GFP_COMP. | |
191 | */ | |
192 | if (pool->p.order) | |
193 | gfp |= __GFP_COMP; | |
194 | ||
195 | /* FUTURE development: | |
196 | * | |
197 | * Current slow-path essentially falls back to single page | |
198 | * allocations, which doesn't improve performance. This code | |
199 | * need bulk allocation support from the page allocator code. | |
200 | */ | |
201 | ||
202 | /* Cache was empty, do real allocation */ | |
203 | page = alloc_pages_node(pool->p.nid, gfp, pool->p.order); | |
204 | if (!page) | |
205 | return NULL; | |
206 | ||
207 | if (!(pool->p.flags & PP_FLAG_DMA_MAP)) | |
208 | goto skip_dma_map; | |
209 | ||
1567b85e IA |
210 | /* Setup DMA mapping: use 'struct page' area for storing DMA-addr |
211 | * since dma_addr_t can be either 32 or 64 bits and does not always fit | |
212 | * into page private data (i.e 32bit cpu with 64bit DMA caps) | |
ff7d6b27 JDB |
213 | * This mapping is kept for lifetime of page, until leaving pool. |
214 | */ | |
13f16d9d JDB |
215 | dma = dma_map_page_attrs(pool->p.dev, page, 0, |
216 | (PAGE_SIZE << pool->p.order), | |
217 | pool->p.dma_dir, DMA_ATTR_SKIP_CPU_SYNC); | |
ff7d6b27 JDB |
218 | if (dma_mapping_error(pool->p.dev, dma)) { |
219 | put_page(page); | |
220 | return NULL; | |
221 | } | |
1567b85e | 222 | page->dma_addr = dma; |
ff7d6b27 | 223 | |
e68bc756 LB |
224 | if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) |
225 | page_pool_dma_sync_for_device(pool, page, pool->p.max_len); | |
226 | ||
ff7d6b27 | 227 | skip_dma_map: |
99c07c43 JDB |
228 | /* Track how many pages are held 'in-flight' */ |
229 | pool->pages_state_hold_cnt++; | |
230 | ||
32c28f7e JDB |
231 | trace_page_pool_state_hold(pool, page, pool->pages_state_hold_cnt); |
232 | ||
ff7d6b27 JDB |
233 | /* When page just alloc'ed is should/must have refcnt 1. */ |
234 | return page; | |
235 | } | |
236 | ||
237 | /* For using page_pool replace: alloc_pages() API calls, but provide | |
238 | * synchronization guarantee for allocation side. | |
239 | */ | |
240 | struct page *page_pool_alloc_pages(struct page_pool *pool, gfp_t gfp) | |
241 | { | |
242 | struct page *page; | |
243 | ||
244 | /* Fast-path: Get a page from cache */ | |
245 | page = __page_pool_get_cached(pool); | |
246 | if (page) | |
247 | return page; | |
248 | ||
249 | /* Slow-path: cache empty, do real allocation */ | |
250 | page = __page_pool_alloc_pages_slow(pool, gfp); | |
251 | return page; | |
252 | } | |
253 | EXPORT_SYMBOL(page_pool_alloc_pages); | |
254 | ||
99c07c43 JDB |
255 | /* Calculate distance between two u32 values, valid if distance is below 2^(31) |
256 | * https://en.wikipedia.org/wiki/Serial_number_arithmetic#General_Solution | |
257 | */ | |
258 | #define _distance(a, b) (s32)((a) - (b)) | |
259 | ||
260 | static s32 page_pool_inflight(struct page_pool *pool) | |
261 | { | |
262 | u32 release_cnt = atomic_read(&pool->pages_state_release_cnt); | |
263 | u32 hold_cnt = READ_ONCE(pool->pages_state_hold_cnt); | |
c3f812ce | 264 | s32 inflight; |
99c07c43 | 265 | |
c3f812ce | 266 | inflight = _distance(hold_cnt, release_cnt); |
99c07c43 | 267 | |
7c9e6942 | 268 | trace_page_pool_release(pool, inflight, hold_cnt, release_cnt); |
99c07c43 JDB |
269 | WARN(inflight < 0, "Negative(%d) inflight packet-pages", inflight); |
270 | ||
c3f812ce | 271 | return inflight; |
99c07c43 JDB |
272 | } |
273 | ||
ff7d6b27 JDB |
274 | /* Cleanup page_pool state from page */ |
275 | static void __page_pool_clean_page(struct page_pool *pool, | |
276 | struct page *page) | |
277 | { | |
1567b85e | 278 | dma_addr_t dma; |
c3f812ce | 279 | int count; |
1567b85e | 280 | |
ff7d6b27 | 281 | if (!(pool->p.flags & PP_FLAG_DMA_MAP)) |
99c07c43 | 282 | goto skip_dma_unmap; |
ff7d6b27 | 283 | |
1567b85e | 284 | dma = page->dma_addr; |
ff7d6b27 | 285 | /* DMA unmap */ |
13f16d9d JDB |
286 | dma_unmap_page_attrs(pool->p.dev, dma, |
287 | PAGE_SIZE << pool->p.order, pool->p.dma_dir, | |
288 | DMA_ATTR_SKIP_CPU_SYNC); | |
1567b85e | 289 | page->dma_addr = 0; |
99c07c43 | 290 | skip_dma_unmap: |
c3f812ce JL |
291 | /* This may be the last page returned, releasing the pool, so |
292 | * it is not safe to reference pool afterwards. | |
293 | */ | |
294 | count = atomic_inc_return(&pool->pages_state_release_cnt); | |
295 | trace_page_pool_state_release(pool, page, count); | |
ff7d6b27 JDB |
296 | } |
297 | ||
a25d50bf IA |
298 | /* unmap the page and clean our state */ |
299 | void page_pool_unmap_page(struct page_pool *pool, struct page *page) | |
300 | { | |
99c07c43 JDB |
301 | /* When page is unmapped, this implies page will not be |
302 | * returned to page_pool. | |
303 | */ | |
a25d50bf IA |
304 | __page_pool_clean_page(pool, page); |
305 | } | |
306 | EXPORT_SYMBOL(page_pool_unmap_page); | |
307 | ||
ff7d6b27 JDB |
308 | /* Return a page to the page allocator, cleaning up our state */ |
309 | static void __page_pool_return_page(struct page_pool *pool, struct page *page) | |
310 | { | |
311 | __page_pool_clean_page(pool, page); | |
99c07c43 | 312 | |
ff7d6b27 JDB |
313 | put_page(page); |
314 | /* An optimization would be to call __free_pages(page, pool->p.order) | |
315 | * knowing page is not part of page-cache (thus avoiding a | |
316 | * __page_cache_release() call). | |
317 | */ | |
318 | } | |
319 | ||
320 | static bool __page_pool_recycle_into_ring(struct page_pool *pool, | |
321 | struct page *page) | |
322 | { | |
323 | int ret; | |
324 | /* BH protection not needed if current is serving softirq */ | |
325 | if (in_serving_softirq()) | |
326 | ret = ptr_ring_produce(&pool->ring, page); | |
327 | else | |
328 | ret = ptr_ring_produce_bh(&pool->ring, page); | |
329 | ||
330 | return (ret == 0) ? true : false; | |
331 | } | |
332 | ||
333 | /* Only allow direct recycling in special circumstances, into the | |
334 | * alloc side cache. E.g. during RX-NAPI processing for XDP_DROP use-case. | |
335 | * | |
336 | * Caller must provide appropriate safe context. | |
337 | */ | |
338 | static bool __page_pool_recycle_direct(struct page *page, | |
339 | struct page_pool *pool) | |
340 | { | |
341 | if (unlikely(pool->alloc.count == PP_ALLOC_CACHE_SIZE)) | |
342 | return false; | |
343 | ||
344 | /* Caller MUST have verified/know (page_ref_count(page) == 1) */ | |
345 | pool->alloc.cache[pool->alloc.count++] = page; | |
346 | return true; | |
347 | } | |
348 | ||
d5394610 SM |
349 | /* page is NOT reusable when: |
350 | * 1) allocated when system is under some pressure. (page_is_pfmemalloc) | |
d5394610 SM |
351 | */ |
352 | static bool pool_page_reusable(struct page_pool *pool, struct page *page) | |
353 | { | |
44768dec | 354 | return !page_is_pfmemalloc(page); |
d5394610 SM |
355 | } |
356 | ||
e68bc756 LB |
357 | void __page_pool_put_page(struct page_pool *pool, struct page *page, |
358 | unsigned int dma_sync_size, bool allow_direct) | |
ff7d6b27 JDB |
359 | { |
360 | /* This allocator is optimized for the XDP mode that uses | |
361 | * one-frame-per-page, but have fallbacks that act like the | |
362 | * regular page allocator APIs. | |
363 | * | |
364 | * refcnt == 1 means page_pool owns page, and can recycle it. | |
365 | */ | |
d5394610 SM |
366 | if (likely(page_ref_count(page) == 1 && |
367 | pool_page_reusable(pool, page))) { | |
ff7d6b27 JDB |
368 | /* Read barrier done in page_ref_count / READ_ONCE */ |
369 | ||
e68bc756 LB |
370 | if (pool->p.flags & PP_FLAG_DMA_SYNC_DEV) |
371 | page_pool_dma_sync_for_device(pool, page, | |
372 | dma_sync_size); | |
373 | ||
ff7d6b27 JDB |
374 | if (allow_direct && in_serving_softirq()) |
375 | if (__page_pool_recycle_direct(page, pool)) | |
376 | return; | |
377 | ||
378 | if (!__page_pool_recycle_into_ring(pool, page)) { | |
379 | /* Cache full, fallback to free pages */ | |
380 | __page_pool_return_page(pool, page); | |
381 | } | |
382 | return; | |
383 | } | |
384 | /* Fallback/non-XDP mode: API user have elevated refcnt. | |
385 | * | |
386 | * Many drivers split up the page into fragments, and some | |
387 | * want to keep doing this to save memory and do refcnt based | |
388 | * recycling. Support this use case too, to ease drivers | |
389 | * switching between XDP/non-XDP. | |
390 | * | |
391 | * In-case page_pool maintains the DMA mapping, API user must | |
392 | * call page_pool_put_page once. In this elevated refcnt | |
393 | * case, the DMA is unmapped/released, as driver is likely | |
394 | * doing refcnt based recycle tricks, meaning another process | |
395 | * will be invoking put_page. | |
396 | */ | |
397 | __page_pool_clean_page(pool, page); | |
398 | put_page(page); | |
399 | } | |
400 | EXPORT_SYMBOL(__page_pool_put_page); | |
401 | ||
402 | static void __page_pool_empty_ring(struct page_pool *pool) | |
403 | { | |
404 | struct page *page; | |
405 | ||
406 | /* Empty recycle ring */ | |
4905bd9a | 407 | while ((page = ptr_ring_consume_bh(&pool->ring))) { |
ff7d6b27 JDB |
408 | /* Verify the refcnt invariant of cached pages */ |
409 | if (!(page_ref_count(page) == 1)) | |
410 | pr_crit("%s() page_pool refcnt %d violation\n", | |
411 | __func__, page_ref_count(page)); | |
412 | ||
413 | __page_pool_return_page(pool, page); | |
414 | } | |
415 | } | |
416 | ||
c3f812ce | 417 | static void page_pool_free(struct page_pool *pool) |
d956a048 | 418 | { |
c3f812ce JL |
419 | if (pool->disconnect) |
420 | pool->disconnect(pool); | |
e54cfd7e JDB |
421 | |
422 | ptr_ring_cleanup(&pool->ring, NULL); | |
f71fec47 JDB |
423 | |
424 | if (pool->p.flags & PP_FLAG_DMA_MAP) | |
425 | put_device(pool->p.dev); | |
426 | ||
e54cfd7e JDB |
427 | kfree(pool); |
428 | } | |
e54cfd7e | 429 | |
7c9e6942 | 430 | static void page_pool_empty_alloc_cache_once(struct page_pool *pool) |
ff7d6b27 JDB |
431 | { |
432 | struct page *page; | |
433 | ||
7c9e6942 JDB |
434 | if (pool->destroy_cnt) |
435 | return; | |
436 | ||
ff7d6b27 JDB |
437 | /* Empty alloc cache, assume caller made sure this is |
438 | * no-longer in use, and page_pool_alloc_pages() cannot be | |
439 | * call concurrently. | |
440 | */ | |
441 | while (pool->alloc.count) { | |
442 | page = pool->alloc.cache[--pool->alloc.count]; | |
443 | __page_pool_return_page(pool, page); | |
444 | } | |
7c9e6942 JDB |
445 | } |
446 | ||
447 | static void page_pool_scrub(struct page_pool *pool) | |
448 | { | |
449 | page_pool_empty_alloc_cache_once(pool); | |
450 | pool->destroy_cnt++; | |
ff7d6b27 JDB |
451 | |
452 | /* No more consumers should exist, but producers could still | |
453 | * be in-flight. | |
454 | */ | |
455 | __page_pool_empty_ring(pool); | |
c3f812ce JL |
456 | } |
457 | ||
458 | static int page_pool_release(struct page_pool *pool) | |
459 | { | |
460 | int inflight; | |
461 | ||
462 | page_pool_scrub(pool); | |
463 | inflight = page_pool_inflight(pool); | |
464 | if (!inflight) | |
465 | page_pool_free(pool); | |
466 | ||
467 | return inflight; | |
468 | } | |
469 | ||
470 | static void page_pool_release_retry(struct work_struct *wq) | |
471 | { | |
472 | struct delayed_work *dwq = to_delayed_work(wq); | |
473 | struct page_pool *pool = container_of(dwq, typeof(*pool), release_dw); | |
474 | int inflight; | |
475 | ||
476 | inflight = page_pool_release(pool); | |
477 | if (!inflight) | |
478 | return; | |
479 | ||
480 | /* Periodic warning */ | |
481 | if (time_after_eq(jiffies, pool->defer_warn)) { | |
482 | int sec = (s32)((u32)jiffies - (u32)pool->defer_start) / HZ; | |
483 | ||
484 | pr_warn("%s() stalled pool shutdown %d inflight %d sec\n", | |
485 | __func__, inflight, sec); | |
486 | pool->defer_warn = jiffies + DEFER_WARN_INTERVAL; | |
487 | } | |
488 | ||
489 | /* Still not ready to be disconnected, retry later */ | |
490 | schedule_delayed_work(&pool->release_dw, DEFER_TIME); | |
491 | } | |
492 | ||
493 | void page_pool_use_xdp_mem(struct page_pool *pool, void (*disconnect)(void *)) | |
494 | { | |
495 | refcount_inc(&pool->user_cnt); | |
496 | pool->disconnect = disconnect; | |
497 | } | |
498 | ||
499 | void page_pool_destroy(struct page_pool *pool) | |
500 | { | |
501 | if (!pool) | |
502 | return; | |
503 | ||
504 | if (!page_pool_put(pool)) | |
505 | return; | |
506 | ||
507 | if (!page_pool_release(pool)) | |
508 | return; | |
509 | ||
510 | pool->defer_start = jiffies; | |
511 | pool->defer_warn = jiffies + DEFER_WARN_INTERVAL; | |
ff7d6b27 | 512 | |
c3f812ce JL |
513 | INIT_DELAYED_WORK(&pool->release_dw, page_pool_release_retry); |
514 | schedule_delayed_work(&pool->release_dw, DEFER_TIME); | |
ff7d6b27 | 515 | } |
c3f812ce | 516 | EXPORT_SYMBOL(page_pool_destroy); |
bc836748 SM |
517 | |
518 | /* Caller must provide appropriate safe context, e.g. NAPI. */ | |
519 | void page_pool_update_nid(struct page_pool *pool, int new_nid) | |
520 | { | |
44768dec JDB |
521 | struct page *page; |
522 | ||
bc836748 SM |
523 | trace_page_pool_update_nid(pool, new_nid); |
524 | pool->p.nid = new_nid; | |
44768dec JDB |
525 | |
526 | /* Flush pool alloc cache, as refill will check NUMA node */ | |
527 | while (pool->alloc.count) { | |
528 | page = pool->alloc.cache[--pool->alloc.count]; | |
529 | __page_pool_return_page(pool, page); | |
530 | } | |
bc836748 SM |
531 | } |
532 | EXPORT_SYMBOL(page_pool_update_nid); |