Messages in this thread |  | | | Date | Fri, 17 Apr 2009 23:42:12 +0200 | | From | Folkert van Heusden <> | | Subject | Re: [PATCH] mutex: have non-spinning mutexes on s390 by default |
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> The adaptive spinning mutexes will not always do what one would expect on > virtualized architectures like s390. Especially the cpu_relax() loop in > mutex_spin_on_owner might hurt if the mutex holding cpu has been scheduled > away by the hypervisor. > We would end up in a cpu_relax() loop when there is no chance that the > state of the mutex changes until the target cpu has been scheduled again by > the hypervisor. > For that reason we should change the default behaviour to no-spin on s390.
Hmmm. Wouldn't this be a change that applies to ibm system p as wel? E.g. with linux in an lpar.
Folkert van Heusden
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