diff options
| author | Michal Hocko <mhocko@suse.com> | 2019-02-20 22:19:54 -0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-03-23 20:09:50 +0100 |
| commit | e6e9d6e290028b0a6b83b563fad9fafa7f1d515e (patch) | |
| tree | 50149b815fcf88aadc1a4d1c981b1fc5017f903d | |
| parent | f3a9c9be0eb42d6374445b5f13698e6e1df13f26 (diff) | |
mm: handle lru_add_drain_all for UP properly
[ Upstream commit 6ea183d60c469560e7b08a83c9804299e84ec9eb ]
Since for_each_cpu(cpu, mask) added by commit 2d3854a37e8b767a
("cpumask: introduce new API, without changing anything") did not
evaluate the mask argument if NR_CPUS == 1 due to CONFIG_SMP=n,
lru_add_drain_all() is hitting WARN_ON() at __flush_work() added by
commit 4d43d395fed12463 ("workqueue: Try to catch flush_work() without
INIT_WORK().") by unconditionally calling flush_work() [1].
Workaround this issue by using CONFIG_SMP=n specific lru_add_drain_all
implementation. There is no real need to defer the implementation to
the workqueue as the draining is going to happen on the local cpu. So
alias lru_add_drain_all to lru_add_drain which does all the necessary
work.
[akpm@linux-foundation.org: fix various build warnings]
[1] https://lkml.kernel.org/r/18a30387-6aa5-6123-e67c-57579ecc3f38@roeck-us.net
Link: http://lkml.kernel.org/r/20190213124334.GH4525@dhcp22.suse.cz
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reported-by: Guenter Roeck <linux@roeck-us.net>
Debugged-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | mm/swap.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/mm/swap.c b/mm/swap.c index 26fc9b5f1b6c..a3fc028e338e 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -321,11 +321,6 @@ static inline void activate_page_drain(int cpu) { } -static bool need_activate_page_drain(int cpu) -{ - return false; -} - void activate_page(struct page *page) { struct zone *zone = page_zone(page); @@ -654,13 +649,15 @@ void lru_add_drain(void) put_cpu(); } +#ifdef CONFIG_SMP + +static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work); + static void lru_add_drain_per_cpu(struct work_struct *dummy) { lru_add_drain(); } -static DEFINE_PER_CPU(struct work_struct, lru_add_drain_work); - /* * Doesn't need any cpu hotplug locking because we do rely on per-cpu * kworkers being shut down before our page_alloc_cpu_dead callback is @@ -703,6 +700,12 @@ void lru_add_drain_all(void) mutex_unlock(&lock); } +#else +void lru_add_drain_all(void) +{ + lru_add_drain(); +} +#endif /** * release_pages - batched put_page() |