[tip: sched/core] cpu/hotplug: Allowing to reset fail injection

["tip-bot2 for Vincent Donnefort" <tip-bot2@linutronix.de>]

The following commit has been merged into the sched/core branch of tip:

Commit-ID:     e58422d9789d5c61bb039e40e4e10781d8d43ac3
Gitweb:        https://git.kernel.org/tip/e58422d9789d5c61bb039e40e4e10781d8d43ac3
Author:        Vincent Donnefort <vincent.donnefort@arm.com>
AuthorDate:    Tue, 16 Feb 2021 10:35:04 
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 01 Mar 2021 18:17:26 +01:00

cpu/hotplug: Allowing to reset fail injection

Currently, the only way of resetting the fail injection is to trigger a
hotplug, hotunplug or both. This is rather annoying for testing
and, as the default value for this file is -1, it seems pretty natural to
let a user write it.

Signed-off-by: Vincent Donnefort <vincent.donnefort@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210216103506.416286-2-vincent.donnefort@arm.com
---
 kernel/cpu.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 1b6302e..9121edf 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -2207,6 +2207,11 @@ static ssize_t write_cpuhp_fail(struct device *dev,
 	if (ret)
 		return ret;
 
+	if (fail == CPUHP_INVALID) {
+		st->fail = fail;
+		return count;
+	}
+
 	if (fail < CPUHP_OFFLINE || fail > CPUHP_ONLINE)
 		return -EINVAL;