system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-09-06 18:01:05 +00:00
Code Issues Packages Projects Releases Wiki Activity

powerpc/pseries/cpuidle: add polling idle for shared processor guests

Browse source 
For shared processor guests (e.g., KVM), add an idle polling mode rather
than immediately returning to the hypervisor when the guest CPU goes
idle.

Test setup is a 2 socket POWER9 with 4 guests running, each with vCPUs
equal to 1/2 of real of CPUs. Saturated each guest with tbench. Using
polling idle gives about 1.4x throughput.

Kernel compile speed was not changed significantly.

Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Nicholas Piggin 2017-10-10 17:11:09 +10:00 committed by Michael Ellerman
parent ced54c08d8
commit f2ac428e0e
1 changed files with 8 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

10
drivers/cpuidle/cpuidle-pseries.c
View file

@ -174,11 +174,17 @@ static struct cpuidle_state dedicated_states[] = {
* States for shared partition case.
*/
static struct cpuidle_state shared_states[] = {
{ /* Snooze */
.name = "snooze",
.desc = "snooze",
.exit_latency = 0,
.target_residency = 0,
.enter = &snooze_loop },
{ /* Shared Cede */
.name = "Shared Cede",
.desc = "Shared Cede",
.exit_latency = 0,
.target_residency = 0,
.exit_latency = 10,
.target_residency = 100,
.enter = &shared_cede_loop },
};