This is like lock_page_killable() but for use by callers who
know they have a folio. Convert __lock_page_killable() to be
__lock_folio_killable(). This saves one call to compound_head() per
contended call to lock_page_killable().
__lock_folio_killable() is 20 bytes smaller than __lock_page_killable()
was. lock_page_maybe_drop_mmap() shrinks by 68 bytes and
__lock_page_or_retry() shrinks by 66 bytes. That's a total of 154 bytes
of text saved.
Signed-off-by: Matthew Wilcox (Oracle) <wi...@infradead.org>
Reviewed-by: Christoph Hellwig <h...@lst.de>
Acked-by: Jeff Layton <jlay...@kernel.org>
---
include/linux/pagemap.h | 15 ++++++++++-----
mm/filemap.c | 17 +++++++++--------
2 files changed, 19 insertions(+), 13 deletions(-)
diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index c59b19f1cb0f..b23b95f771f7 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -715,7 +715,7 @@ static inline bool wake_page_match(struct wait_page_queue
*wait_page,
}
void __lock_folio(struct folio *folio);
-extern int __lock_page_killable(struct page *page);
+int __lock_folio_killable(struct folio *folio);
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,
unsigned int flags);
@@ -755,6 +755,14 @@ static inline void lock_page(struct page *page)
__lock_folio(folio);
}
+static inline int lock_folio_killable(struct folio *folio)
+{
+ might_sleep();
+ if (!trylock_folio(folio))
+ return __lock_folio_killable(folio);
+ return 0;
+}
+
/*
* lock_page_killable is like lock_page but can be interrupted by fatal
* signals. It returns 0 if it locked the page and -EINTR if it was
@@ -762,10 +770,7 @@ static inline void lock_page(struct page *page)
*/
static inline int lock_page_killable(struct page *page)
{
- might_sleep();
- if (!trylock_page(page))
- return __lock_page_killable(page);
- return 0;
+ return lock_folio_killable(page_folio(page));
}
/*
diff --git a/mm/filemap.c b/mm/filemap.c
index 36289a9816b5..2a4fa0b5fa88 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1585,14 +1585,13 @@ void __lock_folio(struct folio *folio)
}
EXPORT_SYMBOL(__lock_folio);
-int __lock_page_killable(struct page *__page)
+int __lock_folio_killable(struct folio *folio)
{
- struct page *page = compound_head(__page);
- wait_queue_head_t *q = page_waitqueue(page);
- return wait_on_page_bit_common(q, page, PG_locked, TASK_KILLABLE,
+ wait_queue_head_t *q = page_waitqueue(&folio->page);
+ return wait_on_page_bit_common(q, &folio->page, PG_locked,
TASK_KILLABLE,
EXCLUSIVE);
}
-EXPORT_SYMBOL_GPL(__lock_page_killable);
+EXPORT_SYMBOL_GPL(__lock_folio_killable);
int __lock_page_async(struct page *page, struct wait_page_queue *wait)
{
@@ -1634,6 +1633,8 @@ int __lock_page_async(struct page *page, struct
wait_page_queue *wait)
int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
unsigned int flags)
{
+ struct folio *folio = page_folio(page);
+
if (fault_flag_allow_retry_first(flags)) {
/*
* CAUTION! In this case, mmap_lock is not released
@@ -1652,13 +1653,13 @@ int __lock_page_or_retry(struct page *page, struct
mm_struct *mm,
if (flags & FAULT_FLAG_KILLABLE) {
int ret;
- ret = __lock_page_killable(page);
+ ret = __lock_folio_killable(folio);
if (ret) {
mmap_read_unlock(mm);
return 0;
}
} else {
- __lock_folio(page_folio(page));
+ __lock_folio(folio);
}
return 1;
@@ -2820,7 +2821,7 @@ 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(&folio->page)) {
+ if (__lock_folio_killable(folio)) {
/*
* We didn't have the right flags to drop the mmap_lock,
* but all fault_handlers only check for fatal signals
--
2.30.2
