diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-22 12:28:23 +0300 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2022-01-22 12:28:23 +0300 |
commit | 1c52283265a462a100ae63ddf58b4e5884acde86 (patch) | |
tree | c0d3fa7a02fc0111bc7e56aa1be88e9b92795704 /mm/filemap.c | |
parent | 8205ae327e396820fb7a176a94768146ac0b87ea (diff) | |
parent | 6e61dde82e8bfe65e8ebbe43da45e615bc529236 (diff) | |
download | linux-1c52283265a462a100ae63ddf58b4e5884acde86.tar.xz |
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.c | 102 |
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); |