[PATCH] acpi/s3: fine-tune measure of suspend time

[Alex Hung]

The time variation can be reduced. For example, the original suspend
time:
  Suspend: 3.966 seconds.
  Suspend: 0.539 seconds.
  Suspend: 1.156 seconds.
After patched:
  Suspend: 0.486 seconds.
  Suspend: 0.508 seconds.
  Suspend: 0.528 seconds.

This is especially true for 1st suspend when kernel is busy with other
kernel modules such as

[  120.123903] fwts: Suspend
[  120.162215] wlp60s0: deauthenticating from ...
[  123.726367] PM: suspend entry (deep)

Signed-off-by: Alex Hung <alex.hung at canonical.com>
---
 src/acpi/s3/s3.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/acpi/s3/s3.c b/src/acpi/s3/s3.c
index 6664db2c..5ec8d5c8 100644
--- a/src/acpi/s3/s3.c
+++ b/src/acpi/s3/s3.c
@@ -411,6 +411,13 @@ static int s3_scan_times(
 			s3_suspend_start = ts;
 			continue;
 		}
+
+		/* Update log time if this is available */
+		if (strstr(txt, "PM: suspend entry")) {
+			s3_suspend_start = ts;
+			continue;
+		}
+
 		if (strstr(txt, FWTS_RESUME)) {
 			s3_resume_finish = ts;
 			continue;
-- 
2.17.1