diff options
| author | Tejun Heo <tj@kernel.org> | 2015-08-18 23:54:57 +0200 |
|---|---|---|
| committer | Jens Axboe <axboe@fb.com> | 2015-08-19 00:49:15 +0200 |
| commit | 4ebc1c61d6185604c97fd0b0355ab668052044ab (patch) | |
| tree | 366acca07997da745139dba40070eea624f768b9 /block | |
| parent | writeback: update writeback tracepoints to report cgroup (diff) | |
| download | linux-4ebc1c61d6185604c97fd0b0355ab668052044ab.tar.xz linux-4ebc1c61d6185604c97fd0b0355ab668052044ab.zip | |
cfq-iosched: simplify control flow in cfq_get_queue()
cfq_get_queue()'s control flow looks like the following.
async_cfqq = NULL;
cfqq = NULL;
if (!is_sync) {
...
async_cfqq = ...;
cfqq = *async_cfqq;
}
if (!cfqq)
cfqq = ...;
if (!is_sync && !(*async_cfqq))
...;
The only thing the local variable init, the second if, and the
async_cfqq test in the third if achieves is to skip cfqq creation and
installation if *async_cfqq was already non-NULL. This is needlessly
complicated with different tests examining the same condition.
Simplify it to the following.
if (!is_sync) {
...
async_cfqq = ...;
cfqq = *async_cfqq;
if (cfqq)
goto out;
}
cfqq = ...;
if (!is_sync)
...;
out:
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Jeff Moyer <jmoyer@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Arianna Avanzini <avanzini.arianna@gmail.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Diffstat (limited to 'block')
| -rw-r--r-- | block/cfq-iosched.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c index c62bb2e650b8..e91093d0c0eb 100644 --- a/block/cfq-iosched.c +++ b/block/cfq-iosched.c @@ -3731,8 +3731,8 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, { int ioprio_class = IOPRIO_PRIO_CLASS(cic->ioprio); int ioprio = IOPRIO_PRIO_DATA(cic->ioprio); - struct cfq_queue **async_cfqq = NULL; - struct cfq_queue *cfqq = NULL; + struct cfq_queue **async_cfqq; + struct cfq_queue *cfqq; if (!is_sync) { if (!ioprio_valid(cic->ioprio)) { @@ -3742,19 +3742,20 @@ cfq_get_queue(struct cfq_data *cfqd, bool is_sync, struct cfq_io_cq *cic, } async_cfqq = cfq_async_queue_prio(cfqd, ioprio_class, ioprio); cfqq = *async_cfqq; + if (cfqq) + goto out; } - if (!cfqq) - cfqq = cfq_find_alloc_queue(cfqd, is_sync, cic, bio, gfp_mask); + cfqq = cfq_find_alloc_queue(cfqd, is_sync, cic, bio, gfp_mask); /* * pin the queue now that it's allocated, scheduler exit will prune it */ - if (!is_sync && !(*async_cfqq)) { + if (!is_sync) { cfqq->ref++; *async_cfqq = cfqq; } - +out: cfqq->ref++; return cfqq; } |