diff options
| -rw-r--r-- | drivers/xen/balloon.c | 15 |
1 files changed, 7 insertions, 8 deletions
diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c index fd933695f232..bf4a23c7c591 100644 --- a/drivers/xen/balloon.c +++ b/drivers/xen/balloon.c @@ -472,7 +472,7 @@ static enum bp_state decrease_reservation(unsigned long nr_pages, gfp_t gfp) } /* - * We avoid multiple worker processes conflicting via the balloon mutex. + * As this is a work item it is guaranteed to run as a single instance only. * We may of course race updates of the target counts (which are protected * by the balloon lock), or with changes to the Xen hard limit, but we will * recover from these in time. @@ -482,9 +482,10 @@ static void balloon_process(struct work_struct *work) enum bp_state state = BP_DONE; long credit; - mutex_lock(&balloon_mutex); do { + mutex_lock(&balloon_mutex); + credit = current_credit(); if (credit > 0) { @@ -499,17 +500,15 @@ static void balloon_process(struct work_struct *work) state = update_schedule(state); -#ifndef CONFIG_PREEMPT - if (need_resched()) - schedule(); -#endif + mutex_unlock(&balloon_mutex); + + cond_resched(); + } while (credit && state == BP_DONE); /* Schedule more work if there is some still to be done. */ if (state == BP_EAGAIN) schedule_delayed_work(&balloon_worker, balloon_stats.schedule_delay * HZ); - - mutex_unlock(&balloon_mutex); } /* Resets the Xen limit, sets new target, and kicks off processing. */ |