diff options
Diffstat (limited to 'mm/filemap.c')
| -rw-r--r-- | mm/filemap.c | 106 |
1 files changed, 16 insertions, 90 deletions
diff --git a/mm/filemap.c b/mm/filemap.c index cc69f174f76b..b5e784f34d98 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -47,7 +47,7 @@ #include <linux/splice.h> #include <linux/rcupdate_wait.h> #include <linux/sched/mm.h> -#include <linux/fsnotify.h> +#include <linux/sysctl.h> #include <asm/pgalloc.h> #include <asm/tlbflush.h> #include "internal.h" @@ -1066,6 +1066,19 @@ static wait_queue_head_t *folio_waitqueue(struct folio *folio) return &folio_wait_table[hash_ptr(folio, PAGE_WAIT_TABLE_BITS)]; } +/* How many times do we accept lock stealing from under a waiter? */ +static int sysctl_page_lock_unfairness = 5; +static const struct ctl_table filemap_sysctl_table[] = { + { + .procname = "page_lock_unfairness", + .data = &sysctl_page_lock_unfairness, + .maxlen = sizeof(sysctl_page_lock_unfairness), + .mode = 0644, + .proc_handler = proc_dointvec_minmax, + .extra1 = SYSCTL_ZERO, + } +}; + void __init pagecache_init(void) { int i; @@ -1074,6 +1087,7 @@ void __init pagecache_init(void) init_waitqueue_head(&folio_wait_table[i]); page_writeback_init(); + register_sysctl_init("vm", filemap_sysctl_table); } /* @@ -1221,9 +1235,6 @@ static inline bool folio_trylock_flag(struct folio *folio, int bit_nr, return true; } -/* How many times do we accept lock stealing from under a waiter? */ -int sysctl_page_lock_unfairness = 5; - static inline int folio_wait_bit_common(struct folio *folio, int bit_nr, int state, enum behavior behavior) { @@ -1367,7 +1378,7 @@ repeat: * @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 + * equivalent to folio_put_wait_locked(folio, 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. @@ -3197,14 +3208,6 @@ static struct file *do_sync_mmap_readahead(struct vm_fault *vmf) unsigned long vm_flags = vmf->vma->vm_flags; unsigned int mmap_miss; - /* - * If we have pre-content watches we need to disable readahead to make - * sure that we don't populate our mapping with 0 filled pages that we - * never emitted an event for. - */ - if (unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) - return fpin; - #ifdef CONFIG_TRANSPARENT_HUGEPAGE /* Use the readahead code, even if readahead is disabled */ if ((vm_flags & VM_HUGEPAGE) && HPAGE_PMD_ORDER <= MAX_PAGECACHE_ORDER) { @@ -3273,10 +3276,6 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, struct file *fpin = NULL; unsigned int mmap_miss; - /* See comment in do_sync_mmap_readahead. */ - if (unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) - return fpin; - /* If we don't want any read-ahead, don't bother */ if (vmf->vma->vm_flags & VM_RAND_READ || !ra->ra_pages) return fpin; @@ -3336,48 +3335,6 @@ static vm_fault_t filemap_fault_recheck_pte_none(struct vm_fault *vmf) } /** - * filemap_fsnotify_fault - maybe emit a pre-content event. - * @vmf: struct vm_fault containing details of the fault. - * - * If we have a pre-content watch on this file we will emit an event for this - * range. If we return anything the fault caller should return immediately, we - * will return VM_FAULT_RETRY if we had to emit an event, which will trigger the - * fault again and then the fault handler will run the second time through. - * - * Return: a bitwise-OR of %VM_FAULT_ codes, 0 if nothing happened. - */ -vm_fault_t filemap_fsnotify_fault(struct vm_fault *vmf) -{ - struct file *fpin = NULL; - int mask = (vmf->flags & FAULT_FLAG_WRITE) ? MAY_WRITE : MAY_ACCESS; - loff_t pos = vmf->pgoff >> PAGE_SHIFT; - size_t count = PAGE_SIZE; - int err; - - /* - * We already did this and now we're retrying with everything locked, - * don't emit the event and continue. - */ - if (vmf->flags & FAULT_FLAG_TRIED) - return 0; - - /* No watches, we're done. */ - if (likely(!FMODE_FSNOTIFY_HSM(vmf->vma->vm_file->f_mode))) - return 0; - - fpin = maybe_unlock_mmap_for_io(vmf, fpin); - if (!fpin) - return VM_FAULT_SIGBUS; - - err = fsnotify_file_area_perm(fpin, mask, &pos, count); - fput(fpin); - if (err) - return VM_FAULT_SIGBUS; - return VM_FAULT_RETRY; -} -EXPORT_SYMBOL_GPL(filemap_fsnotify_fault); - -/** * filemap_fault - read in file data for page fault handling * @vmf: struct vm_fault containing details of the fault * @@ -3481,37 +3438,6 @@ retry_find: */ if (unlikely(!folio_test_uptodate(folio))) { /* - * If this is a precontent file we have can now emit an event to - * try and populate the folio. - */ - if (!(vmf->flags & FAULT_FLAG_TRIED) && - unlikely(FMODE_FSNOTIFY_HSM(file->f_mode))) { - loff_t pos = folio_pos(folio); - size_t count = folio_size(folio); - - /* We're NOWAIT, we have to retry. */ - if (vmf->flags & FAULT_FLAG_RETRY_NOWAIT) { - folio_unlock(folio); - goto out_retry; - } - - if (mapping_locked) - filemap_invalidate_unlock_shared(mapping); - mapping_locked = false; - - folio_unlock(folio); - fpin = maybe_unlock_mmap_for_io(vmf, fpin); - if (!fpin) - goto out_retry; - - error = fsnotify_file_area_perm(fpin, MAY_ACCESS, &pos, - count); - if (error) - ret = VM_FAULT_SIGBUS; - goto out_retry; - } - - /* * If the invalidate lock is not held, the folio was in cache * and uptodate and now it is not. Strange but possible since we * didn't hold the page lock all the time. Let's drop |