rcu_cpu_has_callbacks() is declared int but is actually returning bool and
all call-sites currently use it as bool so the declaration should be bool
as well.
Signed-off-by: Nicholas Mc Guire <[email protected]>
---
./kernel/rcu/tree.c:3538 WARNING: return of wrong type
int != bool,
as the description of rcu_cpu_has_callbacks() states:
" * Return true if the specified CPU has any callback...."
this probably should be a bool
All (3) call sites are conditions and are treating it as boolean.
Patch was compile tested with x86_64_defconfig (implies CONFIG_TREE_RCU=y)
Patch is against 4.1-rc3 (localversion-next is -next-20150511)
kernel/rcu/tree.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index bcc5943..599550c 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3516,7 +3516,7 @@ static int rcu_pending(void)
* non-NULL, store an indication of whether all callbacks are lazy.
* (If there are no callbacks, all of them are deemed to be lazy.)
*/
-static int __maybe_unused rcu_cpu_has_callbacks(bool *all_lazy)
+static bool __maybe_unused rcu_cpu_has_callbacks(bool *all_lazy)
{
bool al = true;
bool hc = false;
--
1.7.10.4
On Mon, May 11, 2015 at 10:51:55AM +0200, Nicholas Mc Guire wrote:
> rcu_cpu_has_callbacks() is declared int but is actually returning bool and
> all call-sites currently use it as bool so the declaration should be bool
> as well.
>
> Signed-off-by: Nicholas Mc Guire <[email protected]>
The patch seems reasonable to me. However...
> ---
>
> ./kernel/rcu/tree.c:3538 WARNING: return of wrong type
> int != bool,
>
> as the description of rcu_cpu_has_callbacks() states:
> " * Return true if the specified CPU has any callback...."
> this probably should be a bool
> All (3) call sites are conditions and are treating it as boolean.
>
> Patch was compile tested with x86_64_defconfig (implies CONFIG_TREE_RCU=y)
...some of this information should be in the commit message, as well as
a description of what tool produced this warning.
With that changed,
Reviewed-by: Josh Triplett <[email protected]>
> Patch is against 4.1-rc3 (localversion-next is -next-20150511)
>
> kernel/rcu/tree.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
> index bcc5943..599550c 100644
> --- a/kernel/rcu/tree.c
> +++ b/kernel/rcu/tree.c
> @@ -3516,7 +3516,7 @@ static int rcu_pending(void)
> * non-NULL, store an indication of whether all callbacks are lazy.
> * (If there are no callbacks, all of them are deemed to be lazy.)
> */
> -static int __maybe_unused rcu_cpu_has_callbacks(bool *all_lazy)
> +static bool __maybe_unused rcu_cpu_has_callbacks(bool *all_lazy)
> {
> bool al = true;
> bool hc = false;
> --
> 1.7.10.4
>
On Mon, 11 May 2015, Josh Triplett wrote:
> On Mon, May 11, 2015 at 10:51:55AM +0200, Nicholas Mc Guire wrote:
> > rcu_cpu_has_callbacks() is declared int but is actually returning bool and
> > all call-sites currently use it as bool so the declaration should be bool
> > as well.
> >
> > Signed-off-by: Nicholas Mc Guire <[email protected]>
>
> The patch seems reasonable to me. However...
>
> > ---
> >
> > ./kernel/rcu/tree.c:3538 WARNING: return of wrong type
> > int != bool,
> >
> > as the description of rcu_cpu_has_callbacks() states:
> > " * Return true if the specified CPU has any callback...."
> > this probably should be a bool
> > All (3) call sites are conditions and are treating it as boolean.
> >
> > Patch was compile tested with x86_64_defconfig (implies CONFIG_TREE_RCU=y)
>
> ...some of this information should be in the commit message, as well as
> a description of what tool produced this warning.
>
The tool is coccinelle - type checking scripts that Im working on and that
produced (with Julia Lawal fixing up my .cocci scripts) a few 1000s of
type missmatches in the overall kernel a few hundred in the ./kernel/* -
so starting to clean up....
> With that changed,
> Reviewed-by: Josh Triplett <[email protected]>
>
thanks - just resend with description moved. and a note that coccinelle was
used.
The full script is though in its current form not yet usable as it is not
classifying type errors - had to do that manually - for the kernel (and
glibc for comparison) this is currently:
component Nr funcs != type %
kernel : 374600 10727 2.85
glibc : 9184 268 2.92
finding kernel glibc
wrong ? : 8 4
sign missmatch : 2279 30
down sized : 435 49
up sized : 910 20
declaration missmatch : 7095 165
as noted - sorting/filtering needed some manual work so nubers
are not that precise. wrong here simply means I could not figure
it out like an int foo() returning a float.
Once this is cleaned up I'll post the type-checking scripts along with
the depressing results...
// Find functions where return type and signature do not match
// V2: with the suggestions/improvements from Julia Lawal added this
// now finds about 10 times as many bad cases ...
//
// Comments:
// Options: --no-includes --include-headers
virtual context
virtual org
virtual report
@match exists@
type T1,T2;
idexpression T1 ok;
idexpression T2 ret;
identifier f;
constant C;
position p;
@@
T1 f(...) {
<+...
(
return ok;
|
return C;
|
return@p ret;
)
...+>
}
@script:python@
p << match.p;
fn << match.f;
T1 << match.T1;
T2 << match.T2;
@@
print "%s:%s WARNING: return of wrong type \n\t %s != %s" % (p[0].file,p[0].line,T1,T2)