linux-kernel - [PATCH v0 02/12] x86/mce: Remove function-local cpus variables

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Date:   Thu,  4 Nov 2021 15:40:25 +0100
From:   Borislav Petkov <bp@...en8.de>
To:     Tony Luck <tony.luck@...el.com>
Cc:     X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH v0 02/12] x86/mce: Remove function-local cpus variables

From: Borislav Petkov <bp@...e.de>

Use num_online_cpus() directly.

No functional changes.

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/kernel/cpu/mce/core.c | 8 ++------
 1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index 52d277c955f9..0dcd7ac7444c 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -989,7 +989,6 @@ static atomic_t global_nwo;
 static int mce_start(int *no_way_out)
 {
 	int order;
-	int cpus = num_online_cpus();
 	u64 timeout = (u64)mca_cfg.monarch_timeout * NSEC_PER_USEC;
 
 	if (!timeout)
@@ -1006,7 +1005,7 @@ static int mce_start(int *no_way_out)
 	/*
 	 * Wait for everyone.
 	 */
-	while (atomic_read(&mce_callin) != cpus) {
+	while (atomic_read(&mce_callin) != num_online_cpus()) {
 		if (mce_timed_out(&timeout,
 				  "Timeout: Not all CPUs entered broadcast exception handler")) {
 			atomic_set(&global_nwo, 0);
@@ -1070,14 +1069,11 @@ static int mce_end(int order)
 	atomic_inc(&mce_executing);
 
 	if (order == 1) {
-		/* CHECKME: Can this race with a parallel hotplug? */
-		int cpus = num_online_cpus();
-
 		/*
 		 * Monarch: Wait for everyone to go through their scanning
 		 * loops.
 		 */
-		while (atomic_read(&mce_executing) <= cpus) {
+		while (atomic_read(&mce_executing) <= num_online_cpus()) {
 			if (mce_timed_out(&timeout,
 					  "Timeout: Monarch CPU unable to finish machine check processing"))
 				goto reset;
-- 
2.29.2