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Fix warning in powernow-k8.c

PATCH In review Brian Gerst 2 participants 4 messages Jun 2, 2005 – Jun 3, 2005

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Brian Gerst

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#0 lore raw

PATCH 1/1 Fix warning in powernow-k8.c

Fix this warning:
powernow-k8.c: In function ‘query_current_values_with_pending_wait’:
powernow-k8.c:110: warning: ‘hi’ may be used uninitialized in this function

Signed-off-by Brian Gerst <[email protected]>
arch/i386/kernel/cpu/cpufreq/powernow-k8.c +2 -3
@@ -110,14 +110,13 @@ static int query_current_values_with_pen
 	u32 lo, hi;
 	u32 i = 0;
 
-	lo = MSR_S_LO_CHANGE_PENDING;
-	while (lo & MSR_S_LO_CHANGE_PENDING) {
+	do {
 		if (i++ > 0x1000000) {
 			printk(KERN_ERR PFX "detected change pending stuck\n");
 			return 1;
 		}
 		rdmsr(MSR_FIDVID_STATUS, lo, hi);
-	}
+	} while (lo & MSR_S_LO_CHANGE_PENDING);
 
 	data->currvid = hi & MSR_S_HI_CURRENT_VID;
 	data->currfid = lo & MSR_S_LO_CURRENT_FID;
#1 lore raw

Hi!

Quoted 4 lines

Fix this warning:
powernow-k8.c: In function ?query_current_values_with_pending_wait?:
powernow-k8.c:110: warning: ?hi? may be used uninitialized in this function

Are you sure?

Original code is clearly buggy; I do not think you need that ugly do {} while loop.

Pavel

Quoted 23 lines
Signed-off-by Brian Gerst <[email protected]>
arch/i386/kernel/cpu/cpufreq/powernow-k8.c +2 -3
@@ -110,14 +110,13 @@ static int query_current_values_with_pen
 	u32 lo, hi;
 	u32 i = 0;
 
-	lo = MSR_S_LO_CHANGE_PENDING;
-	while (lo & MSR_S_LO_CHANGE_PENDING) {
+	do {
 		if (i++ > 0x1000000) {
 			printk(KERN_ERR PFX "detected change pending stuck\n");
 			return 1;
 		}
 		rdmsr(MSR_FIDVID_STATUS, lo, hi);
-	}
+	} while (lo & MSR_S_LO_CHANGE_PENDING);
 
 	data->currvid = hi & MSR_S_HI_CURRENT_VID;
 	data->currfid = lo & MSR_S_LO_CURRENT_FID;
author
#2 lore raw
Quoted 9 lines · Pavel Machek

Hi!

Quoted 4 lines

Fix this warning:
powernow-k8.c: In function ?query_current_values_with_pending_wait?:
powernow-k8.c:110: warning: ?hi? may be used uninitialized in this function

Quoted 4 lines

Are you sure?

Original code is clearly buggy; I do not think you need that ugly do {} while loop.

I'm not sure why you think the loop is ugly. It makes it more obvious (to us humans and the compiler) that the loop is executed at least one time.

Quoted 29 lines

Pavel

Quoted 23 lines
Signed-off-by Brian Gerst <[email protected]>
arch/i386/kernel/cpu/cpufreq/powernow-k8.c +2 -3
@@ -110,14 +110,13 @@ static int query_current_values_with_pen
 	u32 lo, hi;
 	u32 i = 0;
 
-	lo = MSR_S_LO_CHANGE_PENDING;
-	while (lo & MSR_S_LO_CHANGE_PENDING) {
+	do {
 		if (i++ > 0x1000000) {
 			printk(KERN_ERR PFX "detected change pending stuck\n");
 			return 1;
 		}
 		rdmsr(MSR_FIDVID_STATUS, lo, hi);
-	}
+	} while (lo & MSR_S_LO_CHANGE_PENDING);
 
 	data->currvid = hi & MSR_S_HI_CURRENT_VID;
 	data->currfid = lo & MSR_S_LO_CURRENT_FID;
#3 lore raw
Quoted 10 lines · Brian Gerst
Quoted 9 lines · Pavel Machek

Hi!

Quoted 4 lines

Fix this warning:
powernow-k8.c: In function ?query_current_values_with_pending_wait?:
powernow-k8.c:110: warning: ?hi? may be used uninitialized in this function

Quoted 8 lines
Quoted 4 lines

Are you sure?

Original code is clearly buggy; I do not think you need that ugly do {} while loop.

I'm not sure why you think the loop is ugly. It makes it more obvious (to us humans and the compiler) that the loop is executed at least one time.

Oops, sorry, I misread the patch.
Pavel