From: Martin Schwidefsky Date: Tue, 29 Sep 2009 12:25:16 +0000 (+0200) Subject: nohz: Introduce arch_needs_cpu X-Git-Tag: v2.6.33-rc1~363^2~14 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3c5d92a0cfb5103c0d5ab74d4ae6373d3af38148;p=pandora-kernel.git nohz: Introduce arch_needs_cpu Allow the architecture to request a normal jiffy tick when the system goes idle and tick_nohz_stop_sched_tick is called . On s390 the hook is used to prevent the system going fully idle if there has been an interrupt other than a clock comparator interrupt since the last wakeup. On s390 the HiperSockets response time for 1 connection ping-pong goes down from 42 to 34 microseconds. The CPU cost decreases by 27%. Signed-off-by: Martin Schwidefsky LKML-Reference: <20090929122533.402715150@de.ibm.com> Signed-off-by: Thomas Gleixner --- Reading git-diff-tree failed