From: Michael Jeanson Date: Tue, 21 May 2019 20:33:10 +0000 (-0400) Subject: fix: timer/trace: Improve timer tracing (v5.2) X-Git-Tag: v2.12.0-pre~49 X-Git-Url: http://git.lttng.org./?a=commitdiff_plain;h=d88e2fe5c3ea0d2c3055fba824be17223c418854;hp=d88e2fe5c3ea0d2c3055fba824be17223c418854;p=lttng-modules.git fix: timer/trace: Improve timer tracing (v5.2) See upstream commit: commit f28d3d5346e97e60c81f933ac89ccf015430e5cf Author: Anna-Maria Gleixner Date: Thu Mar 21 13:09:21 2019 +0100 timer/trace: Improve timer tracing Timers are added to the timer wheel off by one. This is required in case a timer is queued directly before incrementing jiffies to prevent early timer expiry. When reading a timer trace and relying only on the expiry time of the timer in the timer_start trace point and on the now in the timer_expiry_entry trace point, it seems that the timer fires late. With the current timer_expiry_entry trace point information only now=jiffies is printed but not the value of base->clk. This makes it impossible to draw a conclusion to the index of base->clk and makes it impossible to examine timer problems without additional trace points. Therefore add the base->clk value to the timer_expire_entry trace point, to be able to calculate the index the timer base is located at during collecting expired timers. Signed-off-by: Michael Jeanson Signed-off-by: Mathieu Desnoyers ---