Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
  cfq-iosched: limit coop preemption
  cfq-iosched: fix bad return value cfq_should_preempt()
  backing-dev: bdi sb prune should be in the unregister path, not destroy
  Fix bio_alloc() and bio_kmalloc() documentation
  bio_put(): add bio_clone() to the list of functions in the comment
This commit is contained in:
Linus Torvalds 2009-11-03 18:16:21 -08:00
commit 51bb296b09
3 changed files with 32 additions and 18 deletions

View file

@ -196,6 +196,7 @@ enum cfqq_state_flags {
CFQ_CFQQ_FLAG_slice_new, /* no requests dispatched in slice */
CFQ_CFQQ_FLAG_sync, /* synchronous queue */
CFQ_CFQQ_FLAG_coop, /* has done a coop jump of the queue */
CFQ_CFQQ_FLAG_coop_preempt, /* coop preempt */
};
#define CFQ_CFQQ_FNS(name) \
@ -222,6 +223,7 @@ CFQ_CFQQ_FNS(prio_changed);
CFQ_CFQQ_FNS(slice_new);
CFQ_CFQQ_FNS(sync);
CFQ_CFQQ_FNS(coop);
CFQ_CFQQ_FNS(coop_preempt);
#undef CFQ_CFQQ_FNS
#define cfq_log_cfqq(cfqd, cfqq, fmt, args...) \
@ -945,10 +947,13 @@ static struct cfq_queue *cfq_set_active_queue(struct cfq_data *cfqd,
{
if (!cfqq) {
cfqq = cfq_get_next_queue(cfqd);
if (cfqq)
if (cfqq && !cfq_cfqq_coop_preempt(cfqq))
cfq_clear_cfqq_coop(cfqq);
}
if (cfqq)
cfq_clear_cfqq_coop_preempt(cfqq);
__cfq_set_active_queue(cfqd, cfqq);
return cfqq;
}
@ -2051,7 +2056,7 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
* it's a metadata request and the current queue is doing regular IO.
*/
if (rq_is_meta(rq) && !cfqq->meta_pending)
return false;
return true;
/*
* Allow an RT request to pre-empt an ongoing non-RT cfqq timeslice.
@ -2066,8 +2071,16 @@ cfq_should_preempt(struct cfq_data *cfqd, struct cfq_queue *new_cfqq,
* if this request is as-good as one we would expect from the
* current cfqq, let it preempt
*/
if (cfq_rq_close(cfqd, rq))
if (cfq_rq_close(cfqd, rq) && (!cfq_cfqq_coop(new_cfqq) ||
cfqd->busy_queues == 1)) {
/*
* Mark new queue coop_preempt, so its coop flag will not be
* cleared when new queue gets scheduled at the very first time
*/
cfq_mark_cfqq_coop_preempt(new_cfqq);
cfq_mark_cfqq_coop(new_cfqq);
return true;
}
return false;
}

View file

@ -325,8 +325,16 @@ static void bio_fs_destructor(struct bio *bio)
* @gfp_mask: allocation mask to use
* @nr_iovecs: number of iovecs
*
* Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask
* contains __GFP_WAIT, the allocation is guaranteed to succeed.
* bio_alloc will allocate a bio and associated bio_vec array that can hold
* at least @nr_iovecs entries. Allocations will be done from the
* fs_bio_set. Also see @bio_alloc_bioset and @bio_kmalloc.
*
* If %__GFP_WAIT is set, then bio_alloc will always be able to allocate
* a bio. This is due to the mempool guarantees. To make this work, callers
* must never allocate more than 1 bio at a time from this pool. Callers
* that need to allocate more than 1 bio must always submit the previously
* allocated bio for IO before attempting to allocate a new one. Failure to
* do so can cause livelocks under memory pressure.
*
* RETURNS:
* Pointer to new bio on success, NULL on failure.
@ -350,21 +358,13 @@ static void bio_kmalloc_destructor(struct bio *bio)
}
/**
* bio_alloc - allocate a bio for I/O
* bio_kmalloc - allocate a bio for I/O using kmalloc()
* @gfp_mask: the GFP_ mask given to the slab allocator
* @nr_iovecs: number of iovecs to pre-allocate
*
* Description:
* bio_alloc will allocate a bio and associated bio_vec array that can hold
* at least @nr_iovecs entries. Allocations will be done from the
* fs_bio_set. Also see @bio_alloc_bioset.
*
* If %__GFP_WAIT is set, then bio_alloc will always be able to allocate
* a bio. This is due to the mempool guarantees. To make this work, callers
* must never allocate more than 1 bio at a time from this pool. Callers
* that need to allocate more than 1 bio must always submit the previously
* allocated bio for IO before attempting to allocate a new one. Failure to
* do so can cause livelocks under memory pressure.
* Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask contains
* %__GFP_WAIT, the allocation is guaranteed to succeed.
*
**/
struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs)
@ -407,7 +407,7 @@ EXPORT_SYMBOL(zero_fill_bio);
*
* Description:
* Put a reference to a &struct bio, either one you have gotten with
* bio_alloc or bio_get. The last put of a bio will free it.
* bio_alloc, bio_get or bio_clone. The last put of a bio will free it.
**/
void bio_put(struct bio *bio)
{

View file

@ -628,6 +628,8 @@ static void bdi_prune_sb(struct backing_dev_info *bdi)
void bdi_unregister(struct backing_dev_info *bdi)
{
if (bdi->dev) {
bdi_prune_sb(bdi);
if (!bdi_cap_flush_forker(bdi))
bdi_wb_shutdown(bdi);
bdi_debug_unregister(bdi);
@ -697,7 +699,6 @@ void bdi_destroy(struct backing_dev_info *bdi)
spin_unlock(&inode_lock);
}
bdi_prune_sb(bdi);
bdi_unregister(bdi);
for (i = 0; i < NR_BDI_STAT_ITEMS; i++)