Re: [PATCH] jump_label: unlikely(x) > 0
* H. Peter Anvin wrote: > On 10/11/2013 01:57 PM, Andrew Morton wrote: > > > > I'm sure this was intended instead ;) The patch doesn't seem to make > > any difference in code generation with my gcc. > > > > Which is odd, because doesn't unlikely() booleanize? It's supposed to: include/linux/compiler.h:#define unlikely_notrace(x) __builtin_expect(!!(x), 0) Thanks, Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] jump_label: unlikely(x) 0
* H. Peter Anvin h...@linux.intel.com wrote: On 10/11/2013 01:57 PM, Andrew Morton wrote: I'm sure this was intended instead ;) The patch doesn't seem to make any difference in code generation with my gcc. Which is odd, because doesn't unlikely() booleanize? It's supposed to: include/linux/compiler.h:#define unlikely_notrace(x) __builtin_expect(!!(x), 0) Thanks, Ingo -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] jump_label: unlikely(x) > 0
On 10/11/2013 01:57 PM, Andrew Morton wrote: > > I'm sure this was intended instead ;) The patch doesn't seem to make > any difference in code generation with my gcc. > Which is odd, because doesn't unlikely() booleanize? -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] jump_label: unlikely(x) 0
On 10/11/2013 01:57 PM, Andrew Morton wrote: I'm sure this was intended instead ;) The patch doesn't seem to make any difference in code generation with my gcc. Which is odd, because doesn't unlikely() booleanize? -hpa -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] jump_label: unlikely(x) > 0
On Fri, 11 Oct 2013 22:50:50 +0200 (CEST) Roel Kluin
wrote:
> untested, but wasn't this intended instead?
> --
> if (unlikely(x) > 0) doesn't seem to help branch prediction
>
> ...
>
> --- a/include/linux/jump_label.h
> +++ b/include/linux/jump_label.h
> @@ -132,14 +132,14 @@ static __always_inline void jump_label_init(void)
>
> static __always_inline bool static_key_false(struct static_key *key)
> {
> - if (unlikely(atomic_read(>enabled)) > 0)
> + if (unlikely(atomic_read(>enabled) > 0))
> return true;
> return false;
> }
>
> static __always_inline bool static_key_true(struct static_key *key)
> {
> - if (likely(atomic_read(>enabled)) > 0)
> + if (likely(atomic_read(>enabled) > 0))
> return true;
> return false;
> }
I'm sure this was intended instead ;) The patch doesn't seem to make
any difference in code generation with my gcc.
--
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[PATCH] jump_label: unlikely(x) > 0
untested, but wasn't this intended instead?
--
if (unlikely(x) > 0) doesn't seem to help branch prediction
Signed-off-by: Roel Kluin
---
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index a507907..cf08540 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -132,14 +132,14 @@ static __always_inline void jump_label_init(void)
static __always_inline bool static_key_false(struct static_key *key)
{
- if (unlikely(atomic_read(>enabled)) > 0)
+ if (unlikely(atomic_read(>enabled) > 0))
return true;
return false;
}
static __always_inline bool static_key_true(struct static_key *key)
{
- if (likely(atomic_read(>enabled)) > 0)
+ if (likely(atomic_read(>enabled) > 0))
return true;
return false;
}
--
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[PATCH] jump_label: unlikely(x) 0
untested, but wasn't this intended instead?
--
if (unlikely(x) 0) doesn't seem to help branch prediction
Signed-off-by: Roel Kluin roel.kl...@gmail.com
---
diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index a507907..cf08540 100644
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -132,14 +132,14 @@ static __always_inline void jump_label_init(void)
static __always_inline bool static_key_false(struct static_key *key)
{
- if (unlikely(atomic_read(key-enabled)) 0)
+ if (unlikely(atomic_read(key-enabled) 0))
return true;
return false;
}
static __always_inline bool static_key_true(struct static_key *key)
{
- if (likely(atomic_read(key-enabled)) 0)
+ if (likely(atomic_read(key-enabled) 0))
return true;
return false;
}
--
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Re: [PATCH] jump_label: unlikely(x) 0
On Fri, 11 Oct 2013 22:50:50 +0200 (CEST) Roel Kluin roel.kl...@gmail.com
wrote:
untested, but wasn't this intended instead?
--
if (unlikely(x) 0) doesn't seem to help branch prediction
...
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -132,14 +132,14 @@ static __always_inline void jump_label_init(void)
static __always_inline bool static_key_false(struct static_key *key)
{
- if (unlikely(atomic_read(key-enabled)) 0)
+ if (unlikely(atomic_read(key-enabled) 0))
return true;
return false;
}
static __always_inline bool static_key_true(struct static_key *key)
{
- if (likely(atomic_read(key-enabled)) 0)
+ if (likely(atomic_read(key-enabled) 0))
return true;
return false;
}
I'm sure this was intended instead ;) The patch doesn't seem to make
any difference in code generation with my gcc.
--
To unsubscribe from this list: send the line unsubscribe linux-kernel in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
