| Message ID | 20210511214735.1836149-20-willy@infradead.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Memory folios | expand |
On 5/11/21 11:47 PM, Matthew Wilcox (Oracle) wrote: > This is like lock_page() but for use by callers who know they have a folio. > Convert __lock_page() to be __folio_lock(). This saves one call to > compound_head() per contended call to lock_page(). > > Saves 362 bytes of text; mostly from improved register allocation and > inlining decisions. __folio_lock is 59 bytes while __lock_page was 79. > > Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> > Reviewed-by: Christoph Hellwig <hch@lst.de> > Acked-by: Jeff Layton <jlayton@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> > --- > include/linux/pagemap.h | 24 +++++++++++++++++++----- > mm/filemap.c | 29 +++++++++++++++-------------- > 2 files changed, 34 insertions(+), 19 deletions(-) > > diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h > index 8dbba0074536..9a78397609b8 100644 > --- a/include/linux/pagemap.h > +++ b/include/linux/pagemap.h > @@ -638,7 +638,7 @@ static inline bool wake_page_match(struct wait_page_queue *wait_page, > return true; > } > > -extern void __lock_page(struct page *page); > +void __folio_lock(struct folio *folio); > extern int __lock_page_killable(struct page *page); > extern int __lock_page_async(struct page *page, struct wait_page_queue *wait); > extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, > @@ -646,13 +646,24 @@ extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, > void unlock_page(struct page *page); > void folio_unlock(struct folio *folio); > > +static inline bool folio_trylock(struct folio *folio) > +{ > + return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); > +} > + > /* > * Return true if the page was successfully locked > */ > static inline int trylock_page(struct page *page) > { > - page = compound_head(page); > - return (likely(!test_and_set_bit_lock(PG_locked, &page->flags))); > + return folio_trylock(page_folio(page)); > +} > + > +static inline void folio_lock(struct folio *folio) > +{ > + might_sleep(); > + if (!folio_trylock(folio)) > + __folio_lock(folio); > } > > /* > @@ -660,9 +671,12 @@ static inline int trylock_page(struct page *page) > */ > static inline void lock_page(struct page *page) > { > + struct folio *folio; > might_sleep(); > - if (!trylock_page(page)) > - __lock_page(page); > + > + folio = page_folio(page); > + if (!folio_trylock(folio)) > + __folio_lock(folio); > } > > /* > diff --git a/mm/filemap.c b/mm/filemap.c > index e7a6a58d6cd9..c6e5ba176764 100644 > --- a/mm/filemap.c > +++ b/mm/filemap.c > @@ -1187,7 +1187,7 @@ static void wake_up_page(struct page *page, int bit) > */ > enum behavior { > EXCLUSIVE, /* Hold ref to page and take the bit when woken, like > - * __lock_page() waiting on then setting PG_locked. > + * __folio_lock() waiting on then setting PG_locked. > */ > SHARED, /* Hold ref to page and check the bit when woken, like > * wait_on_page_writeback() waiting on PG_writeback. > @@ -1576,17 +1576,16 @@ void page_endio(struct page *page, bool is_write, int err) > EXPORT_SYMBOL_GPL(page_endio); > > /** > - * __lock_page - get a lock on the page, assuming we need to sleep to get it > - * @__page: the page to lock > + * __folio_lock - Get a lock on the folio, assuming we need to sleep to get it. > + * @folio: The folio to lock > */ > -void __lock_page(struct page *__page) > +void __folio_lock(struct folio *folio) > { > - struct page *page = compound_head(__page); > - wait_queue_head_t *q = page_waitqueue(page); > - wait_on_page_bit_common(q, page, PG_locked, TASK_UNINTERRUPTIBLE, > + wait_queue_head_t *q = page_waitqueue(&folio->page); > + wait_on_page_bit_common(q, &folio->page, PG_locked, TASK_UNINTERRUPTIBLE, > EXCLUSIVE); > } > -EXPORT_SYMBOL(__lock_page); > +EXPORT_SYMBOL(__folio_lock); > > int __lock_page_killable(struct page *__page) > { > @@ -1661,10 +1660,10 @@ int __lock_page_or_retry(struct page *page, struct mm_struct *mm, > return 0; > } > } else { > - __lock_page(page); > + __folio_lock(page_folio(page)); > } > - return 1; > > + return 1; > } > > /** > @@ -2835,7 +2834,9 @@ loff_t mapping_seek_hole_data(struct address_space *mapping, loff_t start, > static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, > struct file **fpin) > { > - if (trylock_page(page)) > + struct folio *folio = page_folio(page); > + > + if (folio_trylock(folio)) > return 1; > > /* > @@ -2848,7 +2849,7 @@ static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, > > *fpin = maybe_unlock_mmap_for_io(vmf, *fpin); > if (vmf->flags & FAULT_FLAG_KILLABLE) { > - if (__lock_page_killable(page)) { > + if (__lock_page_killable(&folio->page)) { > /* > * We didn't have the right flags to drop the mmap_lock, > * but all fault_handlers only check for fatal signals > @@ -2860,11 +2861,11 @@ static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, > return 0; > } > } else > - __lock_page(page); > + __folio_lock(folio); > + > return 1; > } > > - > /* > * Synchronous readahead happens when we don't even find a page in the page > * cache at all. We don't want to perform IO under the mmap sem, so if we have >
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 8dbba0074536..9a78397609b8 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -638,7 +638,7 @@ static inline bool wake_page_match(struct wait_page_queue *wait_page, return true; } -extern void __lock_page(struct page *page); +void __folio_lock(struct folio *folio); extern int __lock_page_killable(struct page *page); extern int __lock_page_async(struct page *page, struct wait_page_queue *wait); extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, @@ -646,13 +646,24 @@ extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm, void unlock_page(struct page *page); void folio_unlock(struct folio *folio); +static inline bool folio_trylock(struct folio *folio) +{ + return likely(!test_and_set_bit_lock(PG_locked, folio_flags(folio, 0))); +} + /* * Return true if the page was successfully locked */ static inline int trylock_page(struct page *page) { - page = compound_head(page); - return (likely(!test_and_set_bit_lock(PG_locked, &page->flags))); + return folio_trylock(page_folio(page)); +} + +static inline void folio_lock(struct folio *folio) +{ + might_sleep(); + if (!folio_trylock(folio)) + __folio_lock(folio); } /* @@ -660,9 +671,12 @@ static inline int trylock_page(struct page *page) */ static inline void lock_page(struct page *page) { + struct folio *folio; might_sleep(); - if (!trylock_page(page)) - __lock_page(page); + + folio = page_folio(page); + if (!folio_trylock(folio)) + __folio_lock(folio); } /* diff --git a/mm/filemap.c b/mm/filemap.c index e7a6a58d6cd9..c6e5ba176764 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1187,7 +1187,7 @@ static void wake_up_page(struct page *page, int bit) */ enum behavior { EXCLUSIVE, /* Hold ref to page and take the bit when woken, like - * __lock_page() waiting on then setting PG_locked. + * __folio_lock() waiting on then setting PG_locked. */ SHARED, /* Hold ref to page and check the bit when woken, like * wait_on_page_writeback() waiting on PG_writeback. @@ -1576,17 +1576,16 @@ void page_endio(struct page *page, bool is_write, int err) EXPORT_SYMBOL_GPL(page_endio); /** - * __lock_page - get a lock on the page, assuming we need to sleep to get it - * @__page: the page to lock + * __folio_lock - Get a lock on the folio, assuming we need to sleep to get it. + * @folio: The folio to lock */ -void __lock_page(struct page *__page) +void __folio_lock(struct folio *folio) { - struct page *page = compound_head(__page); - wait_queue_head_t *q = page_waitqueue(page); - wait_on_page_bit_common(q, page, PG_locked, TASK_UNINTERRUPTIBLE, + wait_queue_head_t *q = page_waitqueue(&folio->page); + wait_on_page_bit_common(q, &folio->page, PG_locked, TASK_UNINTERRUPTIBLE, EXCLUSIVE); } -EXPORT_SYMBOL(__lock_page); +EXPORT_SYMBOL(__folio_lock); int __lock_page_killable(struct page *__page) { @@ -1661,10 +1660,10 @@ int __lock_page_or_retry(struct page *page, struct mm_struct *mm, return 0; } } else { - __lock_page(page); + __folio_lock(page_folio(page)); } - return 1; + return 1; } /** @@ -2835,7 +2834,9 @@ loff_t mapping_seek_hole_data(struct address_space *mapping, loff_t start, static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, struct file **fpin) { - if (trylock_page(page)) + struct folio *folio = page_folio(page); + + if (folio_trylock(folio)) return 1; /* @@ -2848,7 +2849,7 @@ static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, *fpin = maybe_unlock_mmap_for_io(vmf, *fpin); if (vmf->flags & FAULT_FLAG_KILLABLE) { - if (__lock_page_killable(page)) { + if (__lock_page_killable(&folio->page)) { /* * We didn't have the right flags to drop the mmap_lock, * but all fault_handlers only check for fatal signals @@ -2860,11 +2861,11 @@ static int lock_page_maybe_drop_mmap(struct vm_fault *vmf, struct page *page, return 0; } } else - __lock_page(page); + __folio_lock(folio); + return 1; } - /* * Synchronous readahead happens when we don't even find a page in the page * cache at all. We don't want to perform IO under the mmap sem, so if we have