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The test scenario is like commit de1ccfb64824 ("swapfile: fix soft lockup in scan_swap_map_slots") does. On the other hand, scan_swap_map_slots() needs to reach LATENCY_LIMIT before calling cond_resched(), so cond_resched() is needed when failed to find available space to avoid softlockup. Signed-off-by: Longlong Xia --- mm/swapfile.c | 1 + 1 file changed, 1 insertion(+) diff --git a/mm/swapfile.c b/mm/swapfile.c index 908a529bca12..4fa440e87cd6 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -1100,6 +1100,7 @@ int get_swap_pages(int n_goal, swp_entry_t swp_entries[], int entry_size) goto check_out; pr_debug("scan_swap_map of si %d failed to find offset\n", si->type); + cond_resched(); spin_lock(&swap_avail_lock); nextsi: -- 2.25.1