mm/filemap: Add __folio_lock_or_retry()

Convert __lock_page_or_retry() to __folio_lock_or_retry().  This actually
saves 4 bytes in the only caller of lock_page_or_retry() (due to better
register allocation) and saves the 14 byte cost of calling page_folio()
in __folio_lock_or_retry() for a total saving of 18 bytes.  Also use
a bool for the return type.

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: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: William Kucharski <william.kucharski@oracle.com>
Acked-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 77dbb7f..7cf140f 100644 (file)
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -654,7 +654,7 @@ static inline bool wake_page_match(struct wait_page_queue *wait_page,
 
 void __folio_lock(struct folio *folio);
 int __folio_lock_killable(struct folio *folio);
-extern int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
+bool __folio_lock_or_retry(struct folio *folio, struct mm_struct *mm,
                                unsigned int flags);
 void unlock_page(struct page *page);
 void folio_unlock(struct folio *folio);
@@ -715,13 +715,16 @@ static inline int lock_page_killable(struct page *page)
  * caller indicated that it can handle a retry.
  *
  * Return value and mmap_lock implications depend on flags; see
- * __lock_page_or_retry().
+ * __folio_lock_or_retry().
  */
-static inline int lock_page_or_retry(struct page *page, struct mm_struct *mm,
+static inline bool lock_page_or_retry(struct page *page, struct mm_struct *mm,
                                     unsigned int flags)
 {
+       struct folio *folio;
        might_sleep();
-       return trylock_page(page) || __lock_page_or_retry(page, mm, flags);
+
+       folio = page_folio(page);
+       return folio_trylock(folio) || __folio_lock_or_retry(folio, mm, flags);
 }
 
 /*

diff --git a/mm/filemap.c b/mm/filemap.c
index b17b58c..706d121 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1680,48 +1680,46 @@ static int __folio_lock_async(struct folio *folio, struct wait_page_queue *wait)
 
 /*
  * Return values:
- * 1 - page is locked; mmap_lock is still held.
- * 0 - page is not locked.
+ * true - folio is locked; mmap_lock is still held.
+ * false - folio is not locked.
  *     mmap_lock has been released (mmap_read_unlock(), unless flags had both
  *     FAULT_FLAG_ALLOW_RETRY and FAULT_FLAG_RETRY_NOWAIT set, in
  *     which case mmap_lock is still held.
  *
- * If neither ALLOW_RETRY nor KILLABLE are set, will always return 1
- * with the page locked and the mmap_lock unperturbed.
+ * If neither ALLOW_RETRY nor KILLABLE are set, will always return true
+ * with the folio locked and the mmap_lock unperturbed.
  */
-int __lock_page_or_retry(struct page *page, struct mm_struct *mm,
+bool __folio_lock_or_retry(struct folio *folio, 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
                 * even though return 0.
                 */
                if (flags & FAULT_FLAG_RETRY_NOWAIT)
-                       return 0;
+                       return false;
 
                mmap_read_unlock(mm);
                if (flags & FAULT_FLAG_KILLABLE)
                        folio_wait_locked_killable(folio);
                else
                        folio_wait_locked(folio);
-               return 0;
+               return false;
        }
        if (flags & FAULT_FLAG_KILLABLE) {
-               int ret;
+               bool ret;
 
                ret = __folio_lock_killable(folio);
                if (ret) {
                        mmap_read_unlock(mm);
-                       return 0;
+                       return false;
                }
        } else {
                __folio_lock(folio);
        }
 
-       return 1;
+       return true;
 }
 
 /**

diff --git a/mm/memory.c b/mm/memory.c
index adf9b9e..269992b 100644 (file)
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -4258,7 +4258,7 @@ static vm_fault_t do_shared_fault(struct vm_fault *vmf)
  * We enter with non-exclusive mmap_lock (to exclude vma changes,
  * but allow concurrent faults).
  * The mmap_lock may have been released depending on flags and our
- * return value.  See filemap_fault() and __lock_page_or_retry().
+ * return value.  See filemap_fault() and __folio_lock_or_retry().
  * If mmap_lock is released, vma may become invalid (for example
  * by other thread calling munmap()).
  */
@@ -4499,7 +4499,7 @@ static vm_fault_t wp_huge_pud(struct vm_fault *vmf, pud_t orig_pud)
  * concurrent faults).
  *
  * The mmap_lock may have been released depending on flags and our return value.
- * See filemap_fault() and __lock_page_or_retry().
+ * See filemap_fault() and __folio_lock_or_retry().
  */
 static vm_fault_t handle_pte_fault(struct vm_fault *vmf)
 {
@@ -4603,7 +4603,7 @@ unlock:
  * By the time we get here, we already hold the mm semaphore
  *
  * The mmap_lock may have been released depending on flags and our
- * return value.  See filemap_fault() and __lock_page_or_retry().
+ * return value.  See filemap_fault() and __folio_lock_or_retry().
  */
 static vm_fault_t __handle_mm_fault(struct vm_area_struct *vma,
                unsigned long address, unsigned int flags)
@@ -4759,7 +4759,7 @@ static inline void mm_account_fault(struct pt_regs *regs,
  * By the time we get here, we already hold the mm semaphore
  *
  * The mmap_lock may have been released depending on flags and our
- * return value.  See filemap_fault() and __lock_page_or_retry().
+ * return value.  See filemap_fault() and __folio_lock_or_retry().
  */
 vm_fault_t handle_mm_fault(struct vm_area_struct *vma, unsigned long address,
                           unsigned int flags, struct pt_regs *regs)