[PATCH] workqueue: avoid clang warning

[PATCH] workqueue: avoid clang warning

[Arnd Bergmann]

Building with clang shows lots of warning like:

drivers/amba/bus.c:447:8: warning: implicit conversion from 'long long' to 'int' changes value from 4294967248 to -48
      [-Wconstant-conversion]
static DECLARE_DELAYED_WORK(deferred_retry_work, amba_deferred_retry_func);
       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/workqueue.h:187:26: note: expanded from macro 'DECLARE_DELAYED_WORK'
        struct delayed_work n = __DELAYED_WORK_INITIALIZER(n, f, 0)
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/workqueue.h:177:10: note: expanded from macro '__DELAYED_WORK_INITIALIZER'
        .work = __WORK_INITIALIZER((n).work, (f)),                      \
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/workqueue.h:170:10: note: expanded from macro '__WORK_INITIALIZER'
        .data = WORK_DATA_STATIC_INIT(),                                \
                ^~~~~~~~~~~~~~~~~~~~~~~
include/linux/workqueue.h:111:39: note: expanded from macro 'WORK_DATA_STATIC_INIT'
        ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)
        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
include/asm-generic/atomic-long.h:32:41: note: expanded from macro 'ATOMIC_LONG_INIT'
 #define ATOMIC_LONG_INIT(i)     ATOMIC_INIT(i)
                                ~~~~~~~~~~~~^~
arch/arm/include/asm/atomic.h:21:27: note: expanded from macro 'ATOMIC_INIT'
 #define ATOMIC_INIT(i)  { (i) }
                        ~  ^

This makes the type cast explicit, which shuts up the warning.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 include/linux/workqueue.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index a26cc437293c..bde063cefd04 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -106,9 +106,9 @@ struct work_struct {
 #endif
 };
 
-#define WORK_DATA_INIT()	ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL)
+#define WORK_DATA_INIT()	ATOMIC_LONG_INIT((unsigned long)WORK_STRUCT_NO_POOL)
 #define WORK_DATA_STATIC_INIT()	\
-	ATOMIC_LONG_INIT(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC)
+	ATOMIC_LONG_INIT((unsigned long)(WORK_STRUCT_NO_POOL | WORK_STRUCT_STATIC))
 
 struct delayed_work {
 	struct work_struct work;
-- 
2.9.0

Re: [PATCH] workqueue: avoid clang warning

[Tejun Heo]

On Wed, Feb 01, 2017 at 06:01:17PM +0100, Arnd Bergmann wrote:
> Building with clang shows lots of warning like:
> 
> drivers/amba/bus.c:447:8: warning: implicit conversion from 'long long' to 'int' changes value from 4294967248 to -48
...
> arch/arm/include/asm/atomic.h:21:27: note: expanded from macro 'ATOMIC_INIT'
>  #define ATOMIC_INIT(i)  { (i) }
>                         ~  ^
> 
> This makes the type cast explicit, which shuts up the warning.
> 
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>

Applied to wq/for-4.11.  Thanks.

-- 
tejun

[PATCH wq/for-4.11] workqueue: clean up enum definitions in workqueue.h

[Tejun Heo]

>From 225248f9f11895dabd86e118b69220242aece94b Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 2 Feb 2017 15:25:08 -0500

Consistently use UL postfix for mask calculation and drop unnecessary
(unsigned long) cast from the enum definitions.

Signed-off-by: Tejun Heo <tj@kernel.org>
---
Arnd,

I also queued this patch on top.  It shouldn't change anything but can
you please double check?

Thanks.

 include/linux/workqueue.h | 22 +++++++++++-----------
 1 file changed, 11 insertions(+), 11 deletions(-)

diff --git a/include/linux/workqueue.h b/include/linux/workqueue.h
index bde063c..1d2bce1 100644
--- a/include/linux/workqueue.h
+++ b/include/linux/workqueue.h
@@ -39,12 +39,12 @@ enum {
 
 	WORK_STRUCT_COLOR_BITS	= 4,
 
-	WORK_STRUCT_PENDING	= 1 << WORK_STRUCT_PENDING_BIT,
-	WORK_STRUCT_DELAYED	= 1 << WORK_STRUCT_DELAYED_BIT,
-	WORK_STRUCT_PWQ		= 1 << WORK_STRUCT_PWQ_BIT,
-	WORK_STRUCT_LINKED	= 1 << WORK_STRUCT_LINKED_BIT,
+	WORK_STRUCT_PENDING	= 1UL << WORK_STRUCT_PENDING_BIT,
+	WORK_STRUCT_DELAYED	= 1UL << WORK_STRUCT_DELAYED_BIT,
+	WORK_STRUCT_PWQ		= 1UL << WORK_STRUCT_PWQ_BIT,
+	WORK_STRUCT_LINKED	= 1UL << WORK_STRUCT_LINKED_BIT,
 #ifdef CONFIG_DEBUG_OBJECTS_WORK
-	WORK_STRUCT_STATIC	= 1 << WORK_STRUCT_STATIC_BIT,
+	WORK_STRUCT_STATIC	= 1UL << WORK_STRUCT_STATIC_BIT,
 #else
 	WORK_STRUCT_STATIC	= 0,
 #endif
@@ -53,7 +53,7 @@ enum {
 	 * The last color is no color used for works which don't
 	 * participate in workqueue flushing.
 	 */
-	WORK_NR_COLORS		= (1 << WORK_STRUCT_COLOR_BITS) - 1,
+	WORK_NR_COLORS		= (1UL << WORK_STRUCT_COLOR_BITS) - 1,
 	WORK_NO_COLOR		= WORK_NR_COLORS,
 
 	/* not bound to any CPU, prefer the local CPU */
@@ -71,7 +71,7 @@ enum {
 	WORK_OFFQ_FLAG_BASE	= WORK_STRUCT_COLOR_SHIFT,
 
 	__WORK_OFFQ_CANCELING	= WORK_OFFQ_FLAG_BASE,
-	WORK_OFFQ_CANCELING	= (1 << __WORK_OFFQ_CANCELING),
+	WORK_OFFQ_CANCELING	= (1UL << __WORK_OFFQ_CANCELING),
 
 	/*
 	 * When a work item is off queue, its high bits point to the last
@@ -82,16 +82,16 @@ enum {
 	WORK_OFFQ_POOL_SHIFT	= WORK_OFFQ_FLAG_BASE + WORK_OFFQ_FLAG_BITS,
 	WORK_OFFQ_LEFT		= BITS_PER_LONG - WORK_OFFQ_POOL_SHIFT,
 	WORK_OFFQ_POOL_BITS	= WORK_OFFQ_LEFT <= 31 ? WORK_OFFQ_LEFT : 31,
-	WORK_OFFQ_POOL_NONE	= (1LU << WORK_OFFQ_POOL_BITS) - 1,
+	WORK_OFFQ_POOL_NONE	= (1UL << WORK_OFFQ_POOL_BITS) - 1,
 
 	/* convenience constants */
 	WORK_STRUCT_FLAG_MASK	= (1UL << WORK_STRUCT_FLAG_BITS) - 1,
 	WORK_STRUCT_WQ_DATA_MASK = ~WORK_STRUCT_FLAG_MASK,
-	WORK_STRUCT_NO_POOL	= (unsigned long)WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
+	WORK_STRUCT_NO_POOL	= WORK_OFFQ_POOL_NONE << WORK_OFFQ_POOL_SHIFT,
 
 	/* bit mask for work_busy() return values */
-	WORK_BUSY_PENDING	= 1 << 0,
-	WORK_BUSY_RUNNING	= 1 << 1,
+	WORK_BUSY_PENDING	= 1UL << 0,
+	WORK_BUSY_RUNNING	= 1UL << 1,
 
 	/* maximum string length for set_worker_desc() */
 	WORKER_DESC_LEN		= 24,
-- 
2.9.3

Re: [PATCH wq/for-4.11] workqueue: clean up enum definitions in workqueue.h

[Tejun Heo]

On Thu, Feb 02, 2017 at 03:29:22PM -0500, Tejun Heo wrote:
> From 225248f9f11895dabd86e118b69220242aece94b Mon Sep 17 00:00:00 2001
> From: Tejun Heo <tj@kernel.org>
> Date: Thu, 2 Feb 2017 15:25:08 -0500
> 
> Consistently use UL postfix for mask calculation and drop unnecessary
> (unsigned long) cast from the enum definitions.
> 
> Signed-off-by: Tejun Heo <tj@kernel.org>
> ---
> Arnd,
> 
> I also queued this patch on top.  It shouldn't change anything but can
> you please double check?

Ah, never mind.  It does need that ulong cast.  Patch dropped.

Thanks.

-- 
tejun