linux-kernel - [PATCH 8/8] x86, mce, edac: call edac_mce

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Date:	Fri, 17 Jun 2011 17:50:48 +0900
From:	Hidetoshi Seto <seto.hidetoshi@...fujitsu.com>
To:	linux-kernel@...r.kernel.org
CC:	"x86@...nel.org" <x86@...nel.org>, Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	"Luck, Tony" <tony.luck@...el.com>, Borislav Petkov <bp@...64.org>
Subject: [PATCH 8/8] x86, mce, edac: call edac_mce_parse() once per a record

There is no reason to keep it in the cmpxchg loop.
(The loop continues until mcelog acquires buffer to save the record)

And use do-while for the loop here.

Signed-off-by: Hidetoshi Seto <seto.hidetoshi@...fujitsu.com>
---
 arch/x86/kernel/cpu/mcheck/mce.c |   26 +++++++++++++-------------
 1 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/arch/x86/kernel/cpu/mcheck/mce.c b/arch/x86/kernel/cpu/mcheck/mce.c
index bc8a02c..f1d8ce1 100644
--- a/arch/x86/kernel/cpu/mcheck/mce.c
+++ b/arch/x86/kernel/cpu/mcheck/mce.c
@@ -148,21 +148,21 @@ void mce_log(struct mce *mce)
 	/* Emit the trace record: */
 	trace_mce_record(mce);
 
+	/*
+	 * If edac_mce is enabled, it will check the error type and will
+	 * process it, if it is a known error.
+	 * Otherwise, the error will be sent through mcelog interface.
+	 */
+	if (edac_mce_parse(mce))
+		return;
+
 	mce->finished = 0;
 	wmb();
-	for (;;) {
+
+	do {
 		entry = rcu_dereference_check_mce(mcelog.next);
 		for (;;) {
 			/*
-			 * If edac_mce is enabled, it will check the error type
-			 * and will process it, if it is a known error.
-			 * Otherwise, the error will be sent through mcelog
-			 * interface
-			 */
-			if (edac_mce_parse(mce))
-				return;
-
-			/*
 			 * When the buffer fills up discard new entries.
 			 * Assume that the earlier errors are the more
 			 * interesting ones:
@@ -181,10 +181,10 @@ void mce_log(struct mce *mce)
 		}
 		smp_rmb();
 		next = entry + 1;
-		if (cmpxchg(&mcelog.next, entry, next) == entry)
-			break;
-	}
+	} while (cmpxchg(&mcelog.next, entry, next) != entry);
+
 	memcpy(mcelog.entry + entry, mce, sizeof(struct mce));
+
 	wmb();
 	mcelog.entry[entry].finished = 1;
 	wmb();
-- 
1.7.1


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