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| author | Sebastian Ott <sebott@linux.ibm.com> | 2018-06-25 11:23:26 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2018-07-17 07:27:54 +0200 |
| commit | 05b217f4c5573f34f6799698f7d4162c702132bc (patch) | |
| tree | 5678caf88c1ae544b4f3f81f4cdc8332d0ba19b5 /drivers/s390/cio/css.c | |
| parent | 71aa11a40d1a1d80196b55d8dd95be2bc4c1649e (diff) | |
| download | linux-stable-05b217f4c5573f34f6799698f7d4162c702132bc.tar.gz linux-stable-05b217f4c5573f34f6799698f7d4162c702132bc.tar.bz2 linux-stable-05b217f4c5573f34f6799698f7d4162c702132bc.zip | |
s390/css: validate subchannel prior to allocation
In css_alloc_subchannel we allocate the subchannel and do a
validation of the subchannel (to decide if we should look for
devices via this subchannel). On a typical LPAR we find lots
of subchannels to be invalid (because there is no device
attached or the device is blacklisted) leading to lots of
useless kmalloc and kfree calls.
This patch changes the order to only allocate the subchannels
that have been found valid.
Signed-off-by: Sebastian Ott <sebott@linux.ibm.com>
Reviewed-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'drivers/s390/cio/css.c')
| -rw-r--r-- | drivers/s390/cio/css.c | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c index e608e8cad88e..e4d6537cdd87 100644 --- a/drivers/s390/cio/css.c +++ b/drivers/s390/cio/css.c @@ -171,15 +171,20 @@ static void css_subchannel_release(struct device *dev) struct subchannel *css_alloc_subchannel(struct subchannel_id schid) { struct subchannel *sch; + struct schib schib; int ret; + ret = cio_validate_subchannel(schid, &schib); + if (ret < 0) + return ERR_PTR(ret); + sch = kzalloc(sizeof(*sch), GFP_KERNEL | GFP_DMA); if (!sch) return ERR_PTR(-ENOMEM); - ret = cio_validate_subchannel(sch, schid); - if (ret < 0) - goto err; + sch->schid = schid; + sch->schib = schib; + sch->st = schib.pmcw.st; ret = css_sch_create_locks(sch); if (ret) |