diff mbox series

[115/181] mm/memory-failure: do pgoff calculation before for_each_process()

Message ID 20201013235442.aQsdH_NtH%akpm@linux-foundation.org (mailing list archive)
State New, archived
Headers show
Series [001/181] compiler-clang: add build check for clang 10.0.1 | expand

Commit Message

Andrew Morton Oct. 13, 2020, 11:54 p.m. UTC 
From: Xianting Tian <tian.xianting@h3c.com>
Subject: 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.

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

 mm/memory-failure.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)
diff mbox series

Patch

--- a/mm/memory-failure.c~mm-memory-failure-do-pgoff-calculation-before-for_each_process
+++ a/mm/memory-failure.c
@@ -484,11 +484,12 @@  static void collect_procs_file(struct pa
 	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)