Patchwork powerpc/mm: Fix assert_pte_locked to work properly on uniprocessor

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Submitter Kumar Gala
Date Aug. 19, 2009, 1:21 a.m.
Message ID <1250644900-32133-1-git-send-email-galak@kernel.crashing.org>
Download mbox | patch
Permalink /patch/31611/
State Accepted, archived
Commit 797a747a82e23530ee45d2927bf84f3571c1acb2
Headers show

Comments

Kumar Gala - Aug. 19, 2009, 1:21 a.m.
Since the pte_lockptr is a spinlock it gets optimized away on
uniprocessor builds so using spin_is_locked is not correct.  We can use
assert_spin_locked instead and get the proper behavior between UP and
SMP builds.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
---
 arch/powerpc/mm/pgtable.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
Benjamin Herrenschmidt - Aug. 19, 2009, 3:35 a.m.
On Tue, 2009-08-18 at 20:21 -0500, Kumar Gala wrote:
> Since the pte_lockptr is a spinlock it gets optimized away on
> uniprocessor builds so using spin_is_locked is not correct.  We can use
> assert_spin_locked instead and get the proper behavior between UP and
> SMP builds.

Thanks. Applied.

Cheers,
Ben.

> Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
> ---
>  arch/powerpc/mm/pgtable.c |    2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)
> 
> diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
> index 627767d..4b9a27d 100644
> --- a/arch/powerpc/mm/pgtable.c
> +++ b/arch/powerpc/mm/pgtable.c
> @@ -242,7 +242,7 @@ void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
>  	BUG_ON(pud_none(*pud));
>  	pmd = pmd_offset(pud, addr);
>  	BUG_ON(!pmd_present(*pmd));
> -	BUG_ON(!spin_is_locked(pte_lockptr(mm, pmd)));
> +	assert_spin_locked(pte_lockptr(mm, pmd));
>  }
>  #endif /* CONFIG_DEBUG_VM */
>

Patch

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 627767d..4b9a27d 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -242,7 +242,7 @@  void assert_pte_locked(struct mm_struct *mm, unsigned long addr)
 	BUG_ON(pud_none(*pud));
 	pmd = pmd_offset(pud, addr);
 	BUG_ON(!pmd_present(*pmd));
-	BUG_ON(!spin_is_locked(pte_lockptr(mm, pmd)));
+	assert_spin_locked(pte_lockptr(mm, pmd));
 }
 #endif /* CONFIG_DEBUG_VM */