Merge remote-tracking branch 'lsk/v3.10/topic/gator' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / Documentation / kernel-parameters.txt

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 1311a48a7367cb9912875d3d04c0ce1b4f266c1e..15b24a2be6b17faf1a70b98c845dd4c60f3b7c36 100644 (file)
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1240,6 +1240,15 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        See comment before ip2_setup() in
                        drivers/char/ip2/ip2base.c.
 
+       irqaffinity=    [SMP] Set the default irq affinity mask
+                       Format:
+                       <cpu number>,...,<cpu number>
+                       or
+                       <cpu number>-<cpu number>
+                       (must be a positive range in ascending order)
+                       or a mixture
+                       <cpu number>,...,<cpu number>-<cpu number>
+
        irqfixup        [HW]
                        When an interrupt is not handled search all handlers
                        for it. Intended to get systems with badly broken
@@ -3345,6 +3354,21 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                        that this also can be controlled per-workqueue for
                        workqueues visible under /sys/bus/workqueue/.
 
+       workqueue.power_efficient
+                       Per-cpu workqueues are generally preferred because
+                       they show better performance thanks to cache
+                       locality; unfortunately, per-cpu workqueues tend to
+                       be more power hungry than unbound workqueues.
+
+                       Enabling this makes the per-cpu workqueues which
+                       were observed to contribute significantly to power
+                       consumption unbound, leading to measurably lower
+                       power usage at the cost of small performance
+                       overhead.
+
+                       The default value of this parameter is determined by
+                       the config option CONFIG_WQ_POWER_EFFICIENT_DEFAULT.
+
        x2apic_phys     [X86-64,APIC] Use x2apic physical mode instead of
                        default x2apic cluster mode on platforms
                        supporting x2apic.