powerpc/vdso: Correct call frame information

[mirror_ubuntu-bionic-kernel.git] / mm / z3fold.c

diff --git a/mm/z3fold.c b/mm/z3fold.c
index 39e19125d6a019439e5795cbf9be5d54ad2d3349..f33403d718ac92d11f4f04b46cb6d0b8fbbd3070 100644 (file)
--- a/mm/z3fold.c
+++ b/mm/z3fold.c
@@ -144,7 +144,8 @@ enum z3fold_page_flags {
        PAGE_HEADLESS = 0,
        MIDDLE_CHUNK_MAPPED,
        NEEDS_COMPACTING,
-       PAGE_STALE
+       PAGE_STALE,
+       UNDER_RECLAIM
 };
 
 /*****************
@@ -173,6 +174,7 @@ static struct z3fold_header *init_z3fold_page(struct page *page,
        clear_bit(MIDDLE_CHUNK_MAPPED, &page->private);
        clear_bit(NEEDS_COMPACTING, &page->private);
        clear_bit(PAGE_STALE, &page->private);
+       clear_bit(UNDER_RECLAIM, &page->private);
 
        spin_lock_init(&zhdr->page_lock);
        kref_init(&zhdr->refcount);
@@ -467,6 +469,8 @@ static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp,
        spin_lock_init(&pool->lock);
        spin_lock_init(&pool->stale_lock);
        pool->unbuddied = __alloc_percpu(sizeof(struct list_head)*NCHUNKS, 2);
+       if (!pool->unbuddied)
+               goto out_pool;
        for_each_possible_cpu(cpu) {
                struct list_head *unbuddied =
                                per_cpu_ptr(pool->unbuddied, cpu);
@@ -479,7 +483,7 @@ static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp,
        pool->name = name;
        pool->compact_wq = create_singlethread_workqueue(pool->name);
        if (!pool->compact_wq)
-               goto out;
+               goto out_unbuddied;
        pool->release_wq = create_singlethread_workqueue(pool->name);
        if (!pool->release_wq)
                goto out_wq;
@@ -489,8 +493,11 @@ static struct z3fold_pool *z3fold_create_pool(const char *name, gfp_t gfp,
 
 out_wq:
        destroy_workqueue(pool->compact_wq);
-out:
+out_unbuddied:
+       free_percpu(pool->unbuddied);
+out_pool:
        kfree(pool);
+out:
        return NULL;
 }
 
@@ -748,6 +755,10 @@ static void z3fold_free(struct z3fold_pool *pool, unsigned long handle)
                atomic64_dec(&pool->pages_nr);
                return;
        }
+       if (test_bit(UNDER_RECLAIM, &page->private)) {
+               z3fold_page_unlock(zhdr);
+               return;
+       }
        if (test_and_set_bit(NEEDS_COMPACTING, &page->private)) {
                z3fold_page_unlock(zhdr);
                return;
@@ -832,6 +843,8 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
                        kref_get(&zhdr->refcount);
                        list_del_init(&zhdr->buddy);
                        zhdr->cpu = -1;
+                       set_bit(UNDER_RECLAIM, &page->private);
+                       break;
                }
 
                list_del_init(&page->lru);
@@ -879,25 +892,35 @@ static int z3fold_reclaim_page(struct z3fold_pool *pool, unsigned int retries)
                                goto next;
                }
 next:
-               spin_lock(&pool->lock);
                if (test_bit(PAGE_HEADLESS, &page->private)) {
                        if (ret == 0) {
-                               spin_unlock(&pool->lock);
                                free_z3fold_page(page);
                                return 0;
                        }
-               } else if (kref_put(&zhdr->refcount, release_z3fold_page)) {
-                       atomic64_dec(&pool->pages_nr);
+                       spin_lock(&pool->lock);
+                       list_add(&page->lru, &pool->lru);
                        spin_unlock(&pool->lock);
-                       return 0;
+               } else {
+                       z3fold_page_lock(zhdr);
+                       clear_bit(UNDER_RECLAIM, &page->private);
+                       if (kref_put(&zhdr->refcount,
+                                       release_z3fold_page_locked)) {
+                               atomic64_dec(&pool->pages_nr);
+                               return 0;
+                       }
+                       /*
+                        * if we are here, the page is still not completely
+                        * free. Take the global pool lock then to be able
+                        * to add it back to the lru list
+                        */
+                       spin_lock(&pool->lock);
+                       list_add(&page->lru, &pool->lru);
+                       spin_unlock(&pool->lock);
+                       z3fold_page_unlock(zhdr);
                }
 
-               /*
-                * Add to the beginning of LRU.
-                * Pool lock has to be kept here to ensure the page has
-                * not already been released
-                */
-               list_add(&page->lru, &pool->lru);
+               /* We started off locked to we need to lock the pool back */
+               spin_lock(&pool->lock);
        }
        spin_unlock(&pool->lock);
        return -EAGAIN;