[RFC PATCH] x86 / hibernate: Eliminate the redundant smp_ops.play_dead assignment

From: WangYuli
Date: Mon Feb 24 2025 - 02:48:09 EST


It's unnecessary to re-initialize smp_ops.play_dead to play_dead as
it naturally goes back to play_dead in the freshly booted kernel upon
device resume.

Suggested-by: Huacai Chen <chenhuacai@xxxxxxxxxxx>
Co-developed-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
Signed-off-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
Signed-off-by: WangYuli <wangyuli@xxxxxxxxxxxxx>
---
arch/x86/power/cpu.c | 9 ++-------
1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c
index 63230ff8cf4f..023cf9421467 100644
--- a/arch/x86/power/cpu.c
+++ b/arch/x86/power/cpu.c
@@ -297,9 +297,6 @@ static void __noreturn resume_play_dead(void)

int hibernate_resume_nonboot_cpu_disable(void)
{
- void (*play_dead)(void) = smp_ops.play_dead;
- int ret;
-
/*
* Ensure that MONITOR/MWAIT will not be used in the "play dead" loop
* during hibernate image restoration, because it is likely that the
@@ -316,13 +313,11 @@ int hibernate_resume_nonboot_cpu_disable(void)
* resume) sleep afterwards, and the resumed kernel will decide itself
* what to do with them.
*/
- ret = cpuhp_smt_enable();
+ int ret = cpuhp_smt_enable();
if (ret)
return ret;
smp_ops.play_dead = resume_play_dead;
- ret = freeze_secondary_cpus(0);
- smp_ops.play_dead = play_dead;
- return ret;
+ return freeze_secondary_cpus(0);
}
#endif

--
2.47.2