[PATCH 04/10] x86/mce/threshold: Remove the redundant this_cpu_dec_return()

From: Qiuxu Zhuo
Date: Thu Oct 10 2024 - 11:56:16 EST


The 'storm' variable points to this_cpu_ptr(&storm_desc). Access the
'stormy_bank_count' field through the 'storm' to avoid calling
this_cpu_*() on the same per-CPU variable twice.

This minor optimization reduces the text size by 16 bytes.

$ size threshold.o.*
text data bss dec hex filename
1395 1664 0 3059 bf3 threshold.o.old
1379 1664 0 3043 be3 threshold.o.new

No functional changes intended.

Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@xxxxxxxxx>
---
arch/x86/kernel/cpu/mce/threshold.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kernel/cpu/mce/threshold.c b/arch/x86/kernel/cpu/mce/threshold.c
index 89e31e1e5c9c..f4a007616468 100644
--- a/arch/x86/kernel/cpu/mce/threshold.c
+++ b/arch/x86/kernel/cpu/mce/threshold.c
@@ -90,7 +90,7 @@ void cmci_storm_end(unsigned int bank)
storm->banks[bank].in_storm_mode = false;

/* If no banks left in storm mode, stop polling. */
- if (!this_cpu_dec_return(storm_desc.stormy_bank_count))
+ if (!--storm->stormy_bank_count)
mce_timer_kick(false);
}

--
2.17.1