commit 20ee7ccd76442de5360106d2d1d0a8b5513c00fb
author Srinivas Ramana <sramana@codeaurora.org> Wed Nov 23 16:43:42 2016 +0530
committer Srinivas Ramana <sramana@codeaurora.org> Thu Aug 17 17:55:56 2017 +0530
tree ffaa6b3d9284b6e8d4a4dd101b1f665567bed991
parent 3228fead88869480a8a31407ee9c553aa22b1999

time: sched_clock: record cycle count in suspend and resume

Record cycle count and kernel time in ns while entering suspend
and while resuming. This will help in matching up the kernel time
with external subsystems and in recording suspend time in cycles.

Change-Id: If22d9880103c7d54087d0faf4c992259e6b97f08
Signed-off-by: Srinivas Ramana <sramana@codeaurora.org>

kernel/time/sched_clock.c

diff --git a/kernel/time/sched_clock.c b/kernel/time/sched_clock.c
index a26036d..49237ae 100644
--- a/kernel/time/sched_clock.c
+++ b/kernel/time/sched_clock.c
@@ -70,6 +70,9 @@
 
 static struct hrtimer sched_clock_timer;
 static int irqtime = -1;
+static u64 suspend_ns;
+static u64 suspend_cycles;
+static u64 resume_cycles;
 
 core_param(irqtime, irqtime, int, 0400);
 
@@ -274,6 +277,11 @@
 	struct clock_read_data *rd = &cd.read_data[0];
 
 	update_sched_clock();
+
+	suspend_ns = rd->epoch_ns;
+	suspend_cycles = rd->epoch_cyc;
+	pr_info("suspend ns:%17llu	suspend cycles:%17llu\n",
+				rd->epoch_ns, rd->epoch_cyc);
 	hrtimer_cancel(&sched_clock_timer);
 	rd->read_sched_clock = suspended_sched_clock_read;
 
@@ -285,6 +293,8 @@
 	struct clock_read_data *rd = &cd.read_data[0];
 
 	rd->epoch_cyc = cd.actual_read_sched_clock();
+	resume_cycles = rd->epoch_cyc;
+	pr_info("resume cycles:%17llu\n", rd->epoch_cyc);
 	hrtimer_start(&sched_clock_timer, cd.wrap_kt, HRTIMER_MODE_REL);
 	rd->read_sched_clock = cd.actual_read_sched_clock;
 }