Messages in this thread | | | Date | Wed, 3 Jun 2015 17:56:24 -0700 | From | Jeremiah Mahler <> | Subject | [BUG, bisect] hrtimer: severe lag after suspend & resume |
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all,
After a fresh boot, the Chrome web browser behaves normally. Pages load quickly and scroll fast. Even image heavy sites such as images.google.com work fine. However, after a suspend and resume cycle, Chrome becomes very slow. Pages take ten seconds or more to load. The scroll bars and buttons are almost completely unresponsive. Interestingly, I can run Firefox on the same sites and it has no issue whatsoever.
I have bisected the kernel and found that the following commit introduced the bug. It is present in the latest linux-next (20150602).
From 868a3e915f7f5eba8f8cb4f7da2276760807c51c Mon Sep 17 00:00:00 2001 From: Thomas Gleixner <tglx@linutronix.de> Date: Tue, 14 Apr 2015 21:08:37 +0000 Subject: [PATCH] hrtimer: Make offset update smarter On every tick/hrtimer interrupt we update the offset variables of the clock bases. That's silly because these offsets change very seldom. Add a sequence counter to the time keeping code which keeps track of the offset updates (clock_was_set()). Have a sequence cache in the hrtimer cpu bases to evaluate whether the offsets must be updated or not. This allows us later to avoid pointless cacheline pollution. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Preeti U Murthy <preeti@linux.vnet.ibm.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Marcelo Tosatti <mtosatti@redhat.com> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: John Stultz <john.stultz@linaro.org> Link: http://lkml.kernel.org/r/20150414203501.132820245@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: John Stultz <john.stultz@linaro.org> --- include/linux/hrtimer.h | 4 ++-- include/linux/timekeeper_internal.h | 2 ++ kernel/time/hrtimer.c | 3 ++- kernel/time/timekeeping.c | 23 ++++++++++++++++------- kernel/time/timekeeping.h | 7 ++++--- 5 files changed, 26 insertions(+), 13 deletions(-)
-- - Jeremiah Mahler
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