[RFC PATCH 3/4] x86, mwaitt: add document to describe mwaitx

Huang Rui
2015-05-19T08:36:09Z

This patch adds a description in the kernel parameters documentation for
"idle=mwaitx".

Signed-off-by: Huang Rui <ray.huang@amd.com>
---
Documentation/kernel-parameters.txt | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 61ab162..af88c5c 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1363,7 +1363,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
Claim all unknown PCI IDE storage controllers.

idle= [X86]
- Format: idle=poll, idle=halt, idle=nomwait
+ Format: idle=poll, idle=halt, idle=nomwait,
+ idle=mwaitx[,<timer value>]
Poll forces a polling idle loop that can slightly
improve the performance of waking up a idle CPU, but
will use a lot of power and make the system run hot.
@@ -1371,6 +1372,13 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
idle=halt: Halt is forced to be used for CPU idle.
In such case C2/C3 won't be used again.
idle=nomwait: Disable mwait for CPU C-states
+ idle=mwaitx[,<timer value>]: Enable mwaitx and
+ configure max waiting timeout value (usec) for CPU
+ idle. If <timer value> is not specified, the
+ maximum timeout value (ebx=0xffffffff * TSC cycle)
+ will be used. If <timer value> is specified as
+ zero, the timer is disabled. Waiting exits via
+ other reasons, such as an IPI.

ignore_loglevel [KNL]
Ignore loglevel setting - this will print /all/
--
2.1.0