Commit a5998061 authored Jan 23, 2014 by Jamie Liu Committed by Linus Torvalds Jan 23, 2014

mm/swapfile.c: do not skip lowest_bit in scan_swap_map() scan loop

In the second half of scan_swap_map()'s scan loop, offset is set to
si->lowest_bit and then incremented before entering the loop for the
first time, causing si->swap_map[si->lowest_bit] to be skipped.

Signed-off-by: Jamie Liu <jamieliu@google.com>
Cc: Shaohua Li <shli@fusionio.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 0d8a4a37

mm/swapfile.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -616,7 +616,7 @@ static unsigned long scan_swap_map(struct swap_info_struct *si,
		}
		}
		offset = si->lowest_bit;
		while (++offset < scan_base) {
		while (offset < scan_base) {
		if (!si->swap_map[offset]) {
		spin_lock(&si->lock);
		goto checks;
		@@ -629,6 +629,7 @@ static unsigned long scan_swap_map(struct swap_info_struct *si,
		cond_resched();
		latency_ration = LATENCY_LIMIT;
		}
		offset++;
		}
		spin_lock(&si->lock);