lkml.org 
[lkml]   [2018]   [Sep]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 2/6] mm/migrate: Use trylock while resetting rate limit
On Fri, Aug 03, 2018 at 11:43:57AM +0530, Srikar Dronamraju wrote:
> diff --git a/mm/migrate.c b/mm/migrate.c
> index 8c0af0f..dbc2cb7 100644
> --- a/mm/migrate.c
> +++ b/mm/migrate.c
> @@ -1868,16 +1868,24 @@ static struct page *alloc_misplaced_dst_page(struct page *page,
> static bool numamigrate_update_ratelimit(pg_data_t *pgdat,
> unsigned long nr_pages)
> {
> + unsigned long next_window, interval;
> +
> + next_window = READ_ONCE(pgdat->numabalancing_migrate_next_window);
> + interval = msecs_to_jiffies(migrate_interval_millisecs);
> +
> /*
> * Rate-limit the amount of data that is being migrated to a node.
> * Optimal placement is no good if the memory bus is saturated and
> * all the time is being spent migrating!
> */
> - if (time_after(jiffies, next_window)) {
> - spin_lock(&pgdat->numabalancing_migrate_lock);
> + if (time_after(jiffies, next_window) &&
> + spin_trylock(&pgdat->numabalancing_migrate_lock)) {

This patch doesn't apply cleanly; also you introduce @next_window with
this patch, so how can it remove a user of it.

I fixed this up, still weird.

\
 
 \ /
  Last update: 2018-09-06 13:48    [W:0.125 / U:0.152 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site