Heiko Carstens 4d92f50249 s390: reintroduce diag 44 calls for cpu_relax() ... Christian Borntraeger reported that the now missing diag 44 calls (voluntary time slice end) does cause a performance regression for stop_machine() calls if a machine has more virtual cpus than the host has physical cpus. This patch mainly reverts 57f2ffe14f ("s390: remove diag 44 calls from cpu_relax()") with the exception that we still do not issue diag 44 calls if running with smt enabled. Due to group scheduling algorithms when running in LPAR this would lead to significant latencies. However, when running in LPAR we do not have more virtual than physical cpus. Reported-and-tested-by: Christian Borntraeger <borntraeger@de.ibm.com> Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>		2015-01-29 09:19:16 +01:00
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asm	s390: reintroduce diag 44 calls for cpu_relax()	2015-01-29 09:19:16 +01:00
uapi/asm	s390: wire up execveat syscall	2014-12-18 13:37:17 +01:00