From 3de1e176f3c41cf6b17c8439de0ebc211eb2c5aa Mon Sep 17 00:00:00 2001 From: Wanpeng Li Date: Sat, 5 May 2018 04:02:32 -0700 Subject: [PATCH] KVM: X86: Lower the default timer frequency limit to 200us MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit BugLink: http://bugs.launchpad.net/bugs/1794889 [ Upstream commit 4c27625b7a67eb9006963ed2bcf8e53b259b43af ] Anthoine reported: The period used by Windows change over time but it can be 1 milliseconds or less. I saw the limit_periodic_timer_frequency print so 500 microseconds is sometimes reached. As suggested by Paolo, lower the default timer frequency limit to a smaller interval of 200 us (5000 Hz) to leave some headroom. This is required due to Windows 10 changing the scheduler tick limit from 1024 Hz to 2048 Hz. Reported-by: Anthoine Bourgeois Suggested-by: Paolo Bonzini Reviewed-by: Darren Kenny Cc: Paolo Bonzini Cc: Radim Krčmář Cc: Anthoine Bourgeois Cc: Darren Kenny Cc: Jan Kiszka Signed-off-by: Wanpeng Li Signed-off-by: Paolo Bonzini Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Kamal Mostafa Signed-off-by: Stefan Bader --- arch/x86/kvm/x86.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 812fb0d1f95b..42e02675c0c4 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -110,7 +110,7 @@ module_param(ignore_msrs, bool, S_IRUGO | S_IWUSR); static bool __read_mostly report_ignored_msrs = true; module_param(report_ignored_msrs, bool, S_IRUGO | S_IWUSR); -unsigned int min_timer_period_us = 500; +unsigned int min_timer_period_us = 200; module_param(min_timer_period_us, uint, S_IRUGO | S_IWUSR); static bool __read_mostly kvmclock_periodic_sync = true; -- 2.39.2