From: Hans-Joachim Picht <hpicht@redhat.com> Date: Thu, 3 Apr 2008 15:41:25 +0200 Subject: [s390] zcrypt: disable ap polling thread per default Message-id: 20080403134125.GI10542@redhat.com O-Subject: [RHEL5 U3 PATCH 7/7] s390 - zcrypt: Disable ap polling thread per default Bugzilla: 435161 RH-Acked-by: Pete Zaitcev <zaitcev@redhat.com> Description ============ The AP polling thread which is enabled by default will cause a high cpu cost with z/VM. z/VMs polling rate is much lower then the ap poll thread in Linux for System z. This patch disables the ap polling thread per default. Bugzilla ========= BZ 435161 https://bugzilla.redhat.com/show_bug.cgi?id=435161 Upstream status of the patch: ============================= Patch included in linux-2.6 as git commit b90b34c6802865d07f482650eff82a4b38df6d79 Test status: ============ Kernel with patch was built and successfully tested Please ACK. With best regards, Hans drivers/s390/crypto/ap_bus.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c index 2f9c250..73efe9e 100644 --- a/drivers/s390/crypto/ap_bus.c +++ b/drivers/s390/crypto/ap_bus.c @@ -59,9 +59,9 @@ module_param_named(domain, ap_domain_index, int, 0000); MODULE_PARM_DESC(domain, "domain index for ap devices"); EXPORT_SYMBOL(ap_domain_index); -static int ap_thread_flag = 1; +static int ap_thread_flag = 0; module_param_named(poll_thread, ap_thread_flag, int, 0000); -MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 1 (on)."); +MODULE_PARM_DESC(poll_thread, "Turn on/off poll thread, default is 0 (off)."); static struct device *ap_root_device = NULL;