mm/memory-failure: do pgoff calculation before for_each_process()

There is no need to calculate pgoff in each loop of for_each_process(), so
move it to the place before for_each_process(), which can save some CPU
cycles.

Signed-off-by: Xianting Tian <tian.xianting@h3c.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Naoya Horiguchi <naoya.horiguchi@nec.com>
Link: http://lkml.kernel.org/r/20200818082647.34322-1-tian.xianting@h3c.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/mm/memory-failure.c b/mm/memory-failure.c
index a1e7394..24c28f8 100644 (file)
--- a/mm/memory-failure.c
+++ b/mm/memory-failure.c
@@ -484,11 +484,12 @@ static void collect_procs_file(struct page *page, struct list_head *to_kill,
        struct vm_area_struct *vma;
        struct task_struct *tsk;
        struct address_space *mapping = page->mapping;
+       pgoff_t pgoff;
 
        i_mmap_lock_read(mapping);
        read_lock(&tasklist_lock);
+       pgoff = page_to_pgoff(page);
        for_each_process(tsk) {
-               pgoff_t pgoff = page_to_pgoff(page);
                struct task_struct *t = task_early_kill(tsk, force_early);
 
                if (!t)