From 66dac98ed0de7a1125fb0dd7907f238f6b9d2f60 Mon Sep 17 00:00:00 2001 From: Nikanth Karthikesan Date: Tue, 27 Nov 2007 12:47:04 +0100 Subject: [PATCH] io_context sharing - cfq changes changes in the cfq for io_context sharing Signed-off-by: Jens Axboe --- block/cfq-iosched.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index 533af75329e6..dba52b62cef8 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -895,7 +895,7 @@ static void cfq_arm_slice_timer(struct cfq_data *cfqd) * task has exited, don't wait */ cic = cfqd->active_cic; - if (!cic || !cic->ioc->task) + if (!cic || !atomic_read(&cic->ioc->nr_tasks)) return; /* @@ -1178,6 +1178,8 @@ static void cfq_free_io_context(struct io_context *ioc) ioc->ioc_data = NULL; + spin_lock(&ioc->lock); + while ((n = rb_first(&ioc->cic_root)) != NULL) { __cic = rb_entry(n, struct cfq_io_context, rb_node); rb_erase(&__cic->rb_node, &ioc->cic_root); @@ -1189,6 +1191,8 @@ static void cfq_free_io_context(struct io_context *ioc) if (ioc_gone && !elv_ioc_count_read(ioc_count)) complete(ioc_gone); + + spin_unlock(&ioc->lock); } static void cfq_exit_cfqq(struct cfq_data *cfqd, struct cfq_queue *cfqq) @@ -1243,6 +1247,7 @@ static void cfq_exit_io_context(struct io_context *ioc) ioc->ioc_data = NULL; + spin_lock(&ioc->lock); /* * put the reference this task is holding to the various queues */ @@ -1253,6 +1258,8 @@ static void cfq_exit_io_context(struct io_context *ioc) cfq_exit_single_io_context(__cic); n = rb_next(n); } + + spin_unlock(&ioc->lock); } static struct cfq_io_context * @@ -1349,6 +1356,8 @@ static void cfq_ioc_set_ioprio(struct io_context *ioc) struct cfq_io_context *cic; struct rb_node *n; + spin_lock(&ioc->lock); + ioc->ioprio_changed = 0; n = rb_first(&ioc->cic_root); @@ -1358,6 +1367,8 @@ static void cfq_ioc_set_ioprio(struct io_context *ioc) changed_ioprio(cic); n = rb_next(n); } + + spin_unlock(&ioc->lock); } static struct cfq_queue * @@ -1502,6 +1513,7 @@ cfq_cic_rb_lookup(struct cfq_data *cfqd, struct io_context *ioc) if (cic && cic->key == cfqd) return cic; + spin_lock(&ioc->lock); restart: n = ioc->cic_root.rb_node; while (n) { @@ -1519,10 +1531,12 @@ restart: n = n->rb_right; else { ioc->ioc_data = cic; + spin_unlock(&ioc->lock); return cic; } } + spin_unlock(&ioc->lock); return NULL; } @@ -1536,6 +1550,7 @@ cfq_cic_link(struct cfq_data *cfqd, struct io_context *ioc, unsigned long flags; void *k; + spin_lock(&ioc->lock); cic->ioc = ioc; cic->key = cfqd; @@ -1566,6 +1581,7 @@ restart: spin_lock_irqsave(cfqd->queue->queue_lock, flags); list_add(&cic->queue_list, &cfqd->cic_list); spin_unlock_irqrestore(cfqd->queue->queue_lock, flags); + spin_unlock(&ioc->lock); } /* @@ -1659,7 +1675,7 @@ cfq_update_idle_window(struct cfq_data *cfqd, struct cfq_queue *cfqq, enable_idle = cfq_cfqq_idle_window(cfqq); - if (!cic->ioc->task || !cfqd->cfq_slice_idle || + if (!atomic_read(&cic->ioc->nr_tasks) || !cfqd->cfq_slice_idle || (cfqd->hw_tag && CIC_SEEKY(cic))) enable_idle = 0; else if (sample_valid(cic->ttime_samples)) { -- 2.30.2