From: Christian Borntraeger Date: Thu, 15 Nov 2007 19:57:39 +0000 (+0100) Subject: sched: fix accounting of interrupts during guest execution on s390 X-Git-Tag: v2.6.24-rc3~7^2~5 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9778385db35a799d410039be123044a0d3e917a2;p=linux-2.6 sched: fix accounting of interrupts during guest execution on s390 Currently the scheduler checks for PF_VCPU to decide if this timeslice has to be accounted as guest time. On s390 host interrupts are not disabled during guest execution. This causes theses interrupts to be accounted as guest time if CONFIG_VIRT_CPU_ACCOUNTING is set. Solution is to check if an interrupt triggered account_system_time. As the tick is timer interrupt based, we have to subtract hardirq_offset. I tested the patch on s390 with CONFIG_VIRT_CPU_ACCOUNTING and on x86_64. Seems to work. CC: Avi Kivity CC: Laurent Vivier Signed-off-by: Christian Borntraeger Signed-off-by: Ingo Molnar --- diff --git a/kernel/sched.c b/kernel/sched.c index 4fb3532dd7..908335e178 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3390,10 +3390,8 @@ void account_system_time(struct task_struct *p, int hardirq_offset, struct rq *rq = this_rq(); cputime64_t tmp; - if (p->flags & PF_VCPU) { - account_guest_time(p, cputime); - return; - } + if ((p->flags & PF_VCPU) && (irq_count() - hardirq_offset == 0)) + return account_guest_time(p, cputime); p->stime = cputime_add(p->stime, cputime);