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| author | Clive Lin <clive.lin@mediatek.com> | 2023-07-31 14:03:54 +0800 |
|---|---|---|
| committer | Rafael J. Wysocki <rafael.j.wysocki@intel.com> | 2023-08-22 21:37:29 +0200 |
| commit | 5f55836ab41671e005038255fdd60482718d2ca2 (patch) | |
| tree | bbe60899d0d135eba0c3e6e9f88b8472ea69beb9 /kernel/power | |
| parent | 706a741595047797872e669b3101429ab8d378ef (diff) | |
| download | linux-5f55836ab41671e005038255fdd60482718d2ca2.tar.gz linux-5f55836ab41671e005038255fdd60482718d2ca2.tar.bz2 linux-5f55836ab41671e005038255fdd60482718d2ca2.zip | |
PM: QoS: Add check to make sure CPU latency is non-negative
CPU latency should never be negative, which will be incorrectly high
when converted to unsigned data type.
Commit 8d36694245f2 ("PM: QoS: Add check to make sure CPU freq is
non-negative") makes sure CPU frequency is non-negative to fix incorrect
behavior in freqency QoS.
Add an analogous check to make sure CPU latency is non-negative so as to
prevent this problem from happening in CPU latency QoS.
Signed-off-by: Clive Lin <clive.lin@mediatek.com>
[ rjw: Changelog edits ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'kernel/power')
| -rw-r--r-- | kernel/power/qos.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 782d3b41c1f3..4244b069442e 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -220,6 +220,11 @@ static struct pm_qos_constraints cpu_latency_constraints = { .type = PM_QOS_MIN, }; +static inline bool cpu_latency_qos_value_invalid(s32 value) +{ + return value < 0 && value != PM_QOS_DEFAULT_VALUE; +} + /** * cpu_latency_qos_limit - Return current system-wide CPU latency QoS limit. */ @@ -263,7 +268,7 @@ static void cpu_latency_qos_apply(struct pm_qos_request *req, */ void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value) { - if (!req) + if (!req || cpu_latency_qos_value_invalid(value)) return; if (cpu_latency_qos_request_active(req)) { @@ -289,7 +294,7 @@ EXPORT_SYMBOL_GPL(cpu_latency_qos_add_request); */ void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value) { - if (!req) + if (!req || cpu_latency_qos_value_invalid(new_value)) return; if (!cpu_latency_qos_request_active(req)) { |