selftests:timers: globals don't need initialization to 0

Global variables do not need to be initialized to 0 and checkpatch
flags this error in tools/testing/selftests/timers/alarmtimer-suspend.c:

ERROR: do not initialise globals to 0
+int final_ret = 0;

Fix this checkpatch error.

Signed-off-by: Zan Aziz <zanaziz313@gmail.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

kselftests: timers:Remove unneeded semicolon

Eliminate the following coccinelle check warning:
tools/testing/selftests/timers/alarmtimer-suspend.c:82:2-3

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Zhang Mingyu <zhang.mingyu@zte.com.cn>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>

selftests: timers: drop support for !KTEST case

There is no need to keep timers tests in sync with external timers
repo. Drop support for !KTEST to support for building and running
timers tests without kselftest framework.

Reference: https://lkml.org/lkml/2017/8/10/952
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>
Acked-by: John Stultz <john.stultz@linaro.org>

treewide: Fix typo in printk

This patch fix spelling typos found in printk and Kconfig.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

kselftests: timers: Check _ALARM clockids are supported before suspending

It was reported that the alarmtimer-suspend test hangs on older
systems that don't support _ALARM clockids.

This is due to the fact that we don't check if the timer_create
fails, and thus when we suspend, the system will not programatically
resume.

Fix this by checking the timer_create call for errors.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftests: timers: Ease alarmtimer-suspend unreasonable latency value

On the hardware I have, resume latency from an alarm is often
2-3 seconds (with a fair amount of variability due to the RTC's
single second granularity). Having four seconds be the pass/fail
bar is maybe a little too tight, so extend this to 5 seconds.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

kselftests: timers: Increase delay between suspends in alarmtimer-suspend

When testing on some hardware, waiting only a second before
re-triggering suspend can keep TCP connections from re-establishing
which after a number of cycles can cause TCP connections to close
while the test is running.

So extend the delay between suspend calls to 3 seconds to let
the connections stay alive.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

selftests/timers: Add alarmtimer-suspend test from timetests suite

This adds the alarmtimer-suspend test from the timetests suite,
which tests that the alarmtimers wake the system up from suspend
shortly after the time they were set to fire.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>