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From: Peter Fritzsche <peter.fritzsche@gmx.de>
To: Arnd Bergmann <arnd@arndb.de>, Ingo Molnar <mingo@elte.hu>,
	Andrew Morton <akpm@linux-foundation.org>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Mathieu Desnoyers <mathieu.desnoyers>
Cc: Peter Fritzsche <peter.fritzsche@gmx.de>
Subject: [PATCH 2/2] asm-generic: Don't warn that atomic_t is only 24 bit
Date: Wed, 28 Apr 2010 13:10:36 +0200	[thread overview]
Message-ID: <1272453036-18670-1-git-send-email-peter.fritzsche@gmx.de> (raw)
In-Reply-To: <1272451837-17961-1-git-send-email-peter.fritzsche@gmx.de>

32-bit Sparc used to only allow usage of 24-bit of it's atomic_t type.
This was corrected with linux 2.6.3 when Keith M Wesolowski changed the
implementation to use the parisc approach of having an array of
spinlocks to protect the atomic_t.

These warnings were also removed from the sparc implementation when the
new implementation was merged in BKrev:402e4949VThdc6D3iaosSFUgabMfvw,
but the warning still remained in some other places without any
24-bit-only atomic_t implementation inside the kernel.

We should remove these warnings to allow users to rely on the full
32-bit range of atomic_t.

Signed-off-by: Peter Fritzsche <peter.fritzsche@gmx.de>
---
 This should correct the problem mentioned in http://lkml.org/lkml/2010/4/26/33

 include/asm-generic/atomic.h |    8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index c99c64d..345bfda 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -30,8 +30,7 @@
  * atomic_read - read atomic variable
  * @v: pointer of type atomic_t
  *
- * Atomically reads the value of @v.  Note that the guaranteed
- * useful range of an atomic_t is only 24 bits.
+ * Atomically reads the value of @v.
  */
 #define atomic_read(v)	((v)->counter)
 
@@ -40,8 +39,7 @@
  * @v: pointer of type atomic_t
  * @i: required value
  *
- * Atomically sets the value of @v to @i.  Note that the guaranteed
- * useful range of an atomic_t is only 24 bits.
+ * Atomically sets the value of @v to @i.
  */
 #define atomic_set(v, i) (((v)->counter) = (i))
 
@@ -53,7 +51,6 @@
  * @v: pointer of type atomic_t
  *
  * Atomically adds @i to @v and returns the result
- * Note that the guaranteed useful range of an atomic_t is only 24 bits.
  */
 static inline int atomic_add_return(int i, atomic_t *v)
 {
@@ -75,7 +72,6 @@ static inline int atomic_add_return(int i, atomic_t *v)
  * @v: pointer of type atomic_t
  *
  * Atomically subtracts @i from @v and returns the result
- * Note that the guaranteed useful range of an atomic_t is only 24 bits.
  */
 static inline int atomic_sub_return(int i, atomic_t *v)
 {
-- 
1.7.1

WARNING: multiple messages have this Message-ID (diff)
From: Peter Fritzsche <peter.fritzsche@gmx.de>
To: Arnd Bergmann <arnd@arndb.de>, Ingo Molnar <mingo@elte.hu>,
	Andrew Morton <akpm@linux-foundation.org>,
	Heiko Carstens <heiko.carstens@de.ibm.com>,
	Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>,
	linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
	Keith M Wesolowski <wesolows@foobazco.org>
Cc: Peter Fritzsche <peter.fritzsche@gmx.de>
Subject: [PATCH 2/2] asm-generic: Don't warn that atomic_t is only 24 bit
Date: Wed, 28 Apr 2010 13:10:36 +0200	[thread overview]
Message-ID: <1272453036-18670-1-git-send-email-peter.fritzsche@gmx.de> (raw)
Message-ID: <20100428111036.2vGd3F4seyePHQ0jPJJx51BMvr40KASsuPDfDuq9Yf0@z> (raw)
In-Reply-To: <1272451837-17961-1-git-send-email-peter.fritzsche@gmx.de>

32-bit Sparc used to only allow usage of 24-bit of it's atomic_t type.
This was corrected with linux 2.6.3 when Keith M Wesolowski changed the
implementation to use the parisc approach of having an array of
spinlocks to protect the atomic_t.

These warnings were also removed from the sparc implementation when the
new implementation was merged in BKrev:402e4949VThdc6D3iaosSFUgabMfvw,
but the warning still remained in some other places without any
24-bit-only atomic_t implementation inside the kernel.

We should remove these warnings to allow users to rely on the full
32-bit range of atomic_t.

Signed-off-by: Peter Fritzsche <peter.fritzsche@gmx.de>
---
 This should correct the problem mentioned in http://lkml.org/lkml/2010/4/26/33

 include/asm-generic/atomic.h |    8 ++------
 1 files changed, 2 insertions(+), 6 deletions(-)

diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index c99c64d..345bfda 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -30,8 +30,7 @@
  * atomic_read - read atomic variable
  * @v: pointer of type atomic_t
  *
- * Atomically reads the value of @v.  Note that the guaranteed
- * useful range of an atomic_t is only 24 bits.
+ * Atomically reads the value of @v.
  */
 #define atomic_read(v)	((v)->counter)
 
@@ -40,8 +39,7 @@
  * @v: pointer of type atomic_t
  * @i: required value
  *
- * Atomically sets the value of @v to @i.  Note that the guaranteed
- * useful range of an atomic_t is only 24 bits.
+ * Atomically sets the value of @v to @i.
  */
 #define atomic_set(v, i) (((v)->counter) = (i))
 
@@ -53,7 +51,6 @@
  * @v: pointer of type atomic_t
  *
  * Atomically adds @i to @v and returns the result
- * Note that the guaranteed useful range of an atomic_t is only 24 bits.
  */
 static inline int atomic_add_return(int i, atomic_t *v)
 {
@@ -75,7 +72,6 @@ static inline int atomic_add_return(int i, atomic_t *v)
  * @v: pointer of type atomic_t
  *
  * Atomically subtracts @i from @v and returns the result
- * Note that the guaranteed useful range of an atomic_t is only 24 bits.
  */
 static inline int atomic_sub_return(int i, atomic_t *v)
 {
-- 
1.7.1


       reply	other threads:[~2010-04-28 11:10 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <1272451837-17961-1-git-send-email-peter.fritzsche@gmx.de>
2010-04-28 11:10 ` Peter Fritzsche [this message]
2010-04-28 11:10   ` [PATCH 2/2] asm-generic: Don't warn that atomic_t is only 24 bit Peter Fritzsche
2010-04-28 13:33   ` Arnd Bergmann
2010-04-28 13:54     ` Mathieu Desnoyers
2010-04-28 13:54       ` Mathieu Desnoyers
2010-04-28 15:28       ` Jamie Lokier
2010-04-28 16:27         ` Mathieu Desnoyers
2010-04-28 18:42         ` Peter Fritzsche
2010-04-28 18:42           ` Peter Fritzsche
2010-04-29 16:22         ` David Howells
2010-04-29 21:10           ` Mathieu Desnoyers
2010-04-29 21:10             ` Mathieu Desnoyers
2010-04-30  8:53             ` Peter Fritzsche
2010-04-28 16:46   ` David Miller

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