From 2ab80d46fead0309d7f190d8023c8d64b2ffcbd5 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 29 Mar 2021 20:15:19 +0200 Subject: cpuidle: Use s64 as exit_latency_ns and target_residency_ns data type Subsequent changes will cause the exit_latency_ns and target_residency_ns fields in struct cpuidle_state to be used in computations in which data type conversions to u64 may turn a negative number close to zero into a verly large positive number leading to incorrect results. In preparation for that, change the data type of the fields mentioned above to s64, but ensure that they will not be negative themselves. No intentional functional impact. Signed-off-by: Rafael J. Wysocki --- drivers/cpuidle/driver.c | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'drivers') diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 4070e573bf43..f70aa17e2a8e 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -181,9 +181,13 @@ static void __cpuidle_driver_init(struct cpuidle_driver *drv) */ if (s->target_residency > 0) s->target_residency_ns = s->target_residency * NSEC_PER_USEC; + else if (s->target_residency_ns < 0) + s->target_residency_ns = 0; if (s->exit_latency > 0) s->exit_latency_ns = s->exit_latency * NSEC_PER_USEC; + else if (s->exit_latency_ns < 0) + s->exit_latency_ns = 0; } } -- cgit v1.2.3