[PATCH] x86_64: Some updates for boot-options.txt
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/Documentation/x86_64/boot-options.txt b/Documentation/x86_64/boot-options.txt
index b9e6be0..476c0c2 100644
--- a/Documentation/x86_64/boot-options.txt
+++ b/Documentation/x86_64/boot-options.txt
@@ -47,7 +47,7 @@
notsc
Don't use the CPU time stamp counter to read the wall time.
This can be used to work around timing problems on multiprocessor systems
- with not properly synchronized CPUs. Only useful with a SMP kernel
+ with not properly synchronized CPUs.
report_lost_ticks
Report when timer interrupts are lost because some code turned off
@@ -74,6 +74,9 @@
event. This will make the CPUs eat a lot more power, but may be useful
to get slightly better performance in multiprocessor benchmarks. It also
makes some profiling using performance counters more accurate.
+ Please note that on systems with MONITOR/MWAIT support (like Intel EM64T
+ CPUs) this option has no performance advantage over the normal idle loop.
+ It may also interact badly with hyperthreading.
Rebooting
@@ -178,6 +181,5 @@
Misc
noreplacement Don't replace instructions with more appropiate ones
- for the CPU. This may be useful on asymmetric MP systems
- where some CPU have less capabilities than the others.
-
+ for the CPU. This may be useful on asymmetric MP systems
+ where some CPU have less capabilities than the others.