Messages in this thread Patch in this message | | | Date | Fri, 10 Feb 2012 14:29:49 -0800 | From | Greg KH <> | Subject | [patch 30/86] PM / QoS: CPU C-state breakage with PM Qos change |
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3.2-stable review patch. If anyone has any objections, please let me know.
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From: Venkatesh Pallipadi <venki@google.com>
commit d020283dc694c9ec31b410f522252f7a8397e67d upstream.
Looks like change "PM QoS: Move and rename the implementation files" merged during the 3.2 development cycle made PM QoS depend on CONFIG_PM which depends on (PM_SLEEP || PM_RUNTIME).
That breaks CPU C-states with kernels not having these CONFIGs, causing CPUs to spend time in Polling loop idle instead of going into deep C-states, consuming way way more power. This is with either acpi idle or intel idle enabled.
Either CONFIG_PM should be enabled with any pm_qos users or the !CONFIG_PM pm_qos_request() should return sane defaults not to break the existing users. Here's is the patch for the latter option.
[rjw: Modified the changelog slightly.]
Signed-off-by: Venkatesh Pallipadi <venki@google.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
--- include/linux/pm_qos.h | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-)
--- a/include/linux/pm_qos.h +++ b/include/linux/pm_qos.h @@ -107,7 +107,19 @@ static inline void pm_qos_remove_request { return; } static inline int pm_qos_request(int pm_qos_class) - { return 0; } +{ + switch (pm_qos_class) { + case PM_QOS_CPU_DMA_LATENCY: + return PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE; + case PM_QOS_NETWORK_LATENCY: + return PM_QOS_NETWORK_LAT_DEFAULT_VALUE; + case PM_QOS_NETWORK_THROUGHPUT: + return PM_QOS_NETWORK_THROUGHPUT_DEFAULT_VALUE; + default: + return PM_QOS_DEFAULT_VALUE; + } +} + static inline int pm_qos_add_notifier(int pm_qos_class, struct notifier_block *notifier) { return 0; }
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