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authorLinus Torvalds <torvalds@linux-foundation.org>2022-01-22 11:28:23 +0200
committerLinus Torvalds <torvalds@linux-foundation.org>2022-01-22 11:28:23 +0200
commit1c52283265a462a100ae63ddf58b4e5884acde86 (patch)
treec0d3fa7a02fc0111bc7e56aa1be88e9b92795704 /mm/filemap.c
parent8205ae327e396820fb7a176a94768146ac0b87ea (diff)
parent6e61dde82e8bfe65e8ebbe43da45e615bc529236 (diff)
Merge branch 'akpm' (patches from Andrew)
Merge yet more updates from Andrew Morton: "This is the post-linux-next queue. Material which was based on or dependent upon material which was in -next. 69 patches. Subsystems affected by this patch series: mm (migration and zsmalloc), sysctl, proc, and lib" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (69 commits) mm: hide the FRONTSWAP Kconfig symbol frontswap: remove support for multiple ops mm: mark swap_lock and swap_active_head static frontswap: simplify frontswap_register_ops frontswap: remove frontswap_test mm: simplify try_to_unuse frontswap: remove the frontswap exports frontswap: simplify frontswap_init frontswap: remove frontswap_curr_pages frontswap: remove frontswap_shrink frontswap: remove frontswap_tmem_exclusive_gets frontswap: remove frontswap_writethrough mm: remove cleancache lib/stackdepot: always do filter_irq_stacks() in stack_depot_save() lib/stackdepot: allow optional init and stack_table allocation by kvmalloc() proc: remove PDE_DATA() completely fs: proc: store PDE()->data into inode->i_private zsmalloc: replace get_cpu_var with local_lock zsmalloc: replace per zpage lock with pool->migrate_lock locking/rwlocks: introduce write_lock_nested ...
Diffstat (limited to 'mm/filemap.c')
-rw-r--r--mm/filemap.c102
1 files changed, 91 insertions, 11 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index afc8f5ca85ac..ad8c39d90bf9 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -21,6 +21,7 @@
#include <linux/gfp.h>
#include <linux/mm.h>
#include <linux/swap.h>
+#include <linux/swapops.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include <linux/file.h>
@@ -34,13 +35,13 @@
#include <linux/cpuset.h>
#include <linux/hugetlb.h>
#include <linux/memcontrol.h>
-#include <linux/cleancache.h>
#include <linux/shmem_fs.h>
#include <linux/rmap.h>
#include <linux/delayacct.h>
#include <linux/psi.h>
#include <linux/ramfs.h>
#include <linux/page_idle.h>
+#include <linux/migrate.h>
#include <asm/pgalloc.h>
#include <asm/tlbflush.h>
#include "internal.h"
@@ -149,16 +150,6 @@ static void filemap_unaccount_folio(struct address_space *mapping,
{
long nr;
- /*
- * if we're uptodate, flush out into the cleancache, otherwise
- * invalidate any existing cleancache entries. We can't leave
- * stale data around in the cleancache once our page is gone
- */
- if (folio_test_uptodate(folio) && folio_test_mappedtodisk(folio))
- cleancache_put_page(&folio->page);
- else
- cleancache_invalidate_page(mapping, &folio->page);
-
VM_BUG_ON_FOLIO(folio_mapped(folio), folio);
if (!IS_ENABLED(CONFIG_DEBUG_VM) && unlikely(folio_mapped(folio))) {
int mapcount;
@@ -1386,6 +1377,95 @@ repeat:
return wait->flags & WQ_FLAG_WOKEN ? 0 : -EINTR;
}
+#ifdef CONFIG_MIGRATION
+/**
+ * migration_entry_wait_on_locked - Wait for a migration entry to be removed
+ * @entry: migration swap entry.
+ * @ptep: mapped pte pointer. Will return with the ptep unmapped. Only required
+ * for pte entries, pass NULL for pmd entries.
+ * @ptl: already locked ptl. This function will drop the lock.
+ *
+ * Wait for a migration entry referencing the given page to be removed. This is
+ * equivalent to put_and_wait_on_page_locked(page, TASK_UNINTERRUPTIBLE) except
+ * this can be called without taking a reference on the page. Instead this
+ * should be called while holding the ptl for the migration entry referencing
+ * the page.
+ *
+ * Returns after unmapping and unlocking the pte/ptl with pte_unmap_unlock().
+ *
+ * This follows the same logic as folio_wait_bit_common() so see the comments
+ * there.
+ */
+void migration_entry_wait_on_locked(swp_entry_t entry, pte_t *ptep,
+ spinlock_t *ptl)
+{
+ struct wait_page_queue wait_page;
+ wait_queue_entry_t *wait = &wait_page.wait;
+ bool thrashing = false;
+ bool delayacct = false;
+ unsigned long pflags;
+ wait_queue_head_t *q;
+ struct folio *folio = page_folio(pfn_swap_entry_to_page(entry));
+
+ q = folio_waitqueue(folio);
+ if (!folio_test_uptodate(folio) && folio_test_workingset(folio)) {
+ if (!folio_test_swapbacked(folio)) {
+ delayacct_thrashing_start();
+ delayacct = true;
+ }
+ psi_memstall_enter(&pflags);
+ thrashing = true;
+ }
+
+ init_wait(wait);
+ wait->func = wake_page_function;
+ wait_page.folio = folio;
+ wait_page.bit_nr = PG_locked;
+ wait->flags = 0;
+
+ spin_lock_irq(&q->lock);
+ folio_set_waiters(folio);
+ if (!folio_trylock_flag(folio, PG_locked, wait))
+ __add_wait_queue_entry_tail(q, wait);
+ spin_unlock_irq(&q->lock);
+
+ /*
+ * If a migration entry exists for the page the migration path must hold
+ * a valid reference to the page, and it must take the ptl to remove the
+ * migration entry. So the page is valid until the ptl is dropped.
+ */
+ if (ptep)
+ pte_unmap_unlock(ptep, ptl);
+ else
+ spin_unlock(ptl);
+
+ for (;;) {
+ unsigned int flags;
+
+ set_current_state(TASK_UNINTERRUPTIBLE);
+
+ /* Loop until we've been woken or interrupted */
+ flags = smp_load_acquire(&wait->flags);
+ if (!(flags & WQ_FLAG_WOKEN)) {
+ if (signal_pending_state(TASK_UNINTERRUPTIBLE, current))
+ break;
+
+ io_schedule();
+ continue;
+ }
+ break;
+ }
+
+ finish_wait(q, wait);
+
+ if (thrashing) {
+ if (delayacct)
+ delayacct_thrashing_end();
+ psi_memstall_leave(&pflags);
+ }
+}
+#endif
+
void folio_wait_bit(struct folio *folio, int bit_nr)
{
folio_wait_bit_common(folio, bit_nr, TASK_UNINTERRUPTIBLE, SHARED);