mm: fix noisy sparse warning in LIBCFS_ALLOC_PRE()

PATCH Superseded Joshua Clayton 3 participants 5 messages Dec 27, 2015 – Dec 30, 2015

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Joshua Clayton

author

2015-12-27 05:12 UTC #0 lore raw

PATCH 1/1 mm: fix noisy sparse warning in LIBCFS_ALLOC_PRE()

running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)

Use "!!" to explicitly convert the result to bool range.

---
 include/linux/gfp.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

include/linux/gfp.h +1 -1

index 91f74e7..6e58a8f 100644
@@ -278,7 +278,7 @@ static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
 
 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
 {
-	return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
+	return (bool __force)!!(gfp_flags & __GFP_DIRECT_RECLAIM);
 }
 
 #ifdef CONFIG_HIGHMEM

Signature · 7 lines

2.6.4

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Al Viro

2015-12-27 05:41 UTC #1 lore raw

Quoted 5 lines · Joshua Clayton

running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)
Use "!!" to explicitly convert the result to bool range.

... and the cast to bool is left in order to...?

include/linux/gfp.h static inline int gfpflags_to_migratetype(const gfp_t gfp_flags) · line 281

Quoted 2 lines

include/linux/gfp.h +1 -1

-	return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
+	return (bool __force)!!(gfp_flags & __GFP_DIRECT_RECLAIM);

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Joshua Clayton

author

2015-12-27 06:39 UTC #2 lore raw

PATCH v2 1/1 mm: fix noisy sparse warning in LIBCFS_ALLOC_PRE()

running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)

Use "!!" to explicitly convert to bool and get rid of the warning.

Signed-off-by Joshua Clayton <[email protected]>

---

Quoted 11 lines · Al Viro

Quoted 5 lines · Joshua Clayton
running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)
Use "!!" to explicitly convert the result to bool range.
... and the cast to bool is left in order to...?
Review
Quoted 2 lines
(quoted diff) +1 -1
-	return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
+	return (bool __force)!!(gfp_flags & __GFP_DIRECT_RECLAIM);

to embarrass me, I suppose. :(
I didn't think about the redundancy of the cast.
Lets try that again.

 include/linux/gfp.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

include/linux/gfp.h +1 -1

index 91f74e7..28ad5f6 100644
@@ -278,7 +278,7 @@ static inline int gfpflags_to_migratetype(const gfp_t gfp_flags)
 
 static inline bool gfpflags_allow_blocking(const gfp_t gfp_flags)
 {
-	return (bool __force)(gfp_flags & __GFP_DIRECT_RECLAIM);
+	return !!(gfp_flags & __GFP_DIRECT_RECLAIM);
 }
 
 #ifdef CONFIG_HIGHMEM

Signature · 9 lines

2.6.4



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Sudip Mukherjee

2015-12-30 04:48 UTC #3 lore raw

In reply to Joshua Clayton

Quoted 6 lines · Joshua Clayton

running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)
Use "!!" to explicitly convert the result to bool range.
---

Signed-off-by missing.

regards
sudip

Joshua Clayton

author

2015-12-30 04:54 UTC #4 lore raw

Quoted 5 lines · Sudip Mukherjee

Quoted 4 lines · Joshua Clayton
running sparse on drivers/staging/lustre results in dozens of warnings:
include/linux/gfp.h:281:41: warning:
odd constant _Bool cast (400000 becomes 1)

Quoted 7 lines

Quoted 2 lines
Use "!!" to explicitly convert the result to bool range.
---
Signed-off-by missing.
regards
sudip

Hmm. I must have forgotten the "-s" in git send-email
I'm thinking a patch this size wouldn't qualify for copyright even if an Oracle Lawyer claimed it.
Nevertheless, all is well. The SOB made it into v2.