linux/drivers/s390
Peter Oberparleiter b207f5a8f9 s390/cio: Relax subchannel scan loop
The CIO layer scans for newly available I/O devices by performing a scan
of available subchannels using the Store Subchannel (STSCH) instruction.
This processing can take a significant amount of time during which no
other task can run on the same CPU (unless CONFIG_PREEMPT has been
enabled). As a result, scheduling latencies for other tasks are
increased noticeably, especially on a single-CPU system.

Fix this problem by explicitly allowing other tasks to be scheduled
each time a subchannel has been processed.

Signed-off-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com>
Reviewed-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2013-12-16 14:37:40 +01:00
..
block s390/dasd: fix memory leak caused by dangling references to request_queue 2013-12-02 15:31:06 +01:00
char s390/sclp: replace uninitialized early_event_mask_sccb variable with sccb_early 2013-12-02 15:31:07 +01:00
cio s390/cio: Relax subchannel scan loop 2013-12-16 14:37:40 +01:00
crypto s390/s390dbf: use debug_level_enabled() where applicable 2013-10-24 17:16:54 +02:00
kvm virtio_ring: change host notification API 2013-10-29 11:28:11 +10:30
net Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2013-11-13 17:40:34 +09:00
scsi Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2013-11-15 16:47:22 -08:00
Makefile