diff mbox

[v2,06/32] s390: reuse asm-generic/barrier.h

Message ID 1451572003-2440-7-git-send-email-mst@redhat.com (mailing list archive)
State New, archived
Headers show

Commit Message

Michael S. Tsirkin Dec. 31, 2015, 7:06 p.m. UTC
On s390 read_barrier_depends, smp_read_barrier_depends
smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
asm-generic variants exactly. Drop the local definitions and pull in
asm-generic/barrier.h instead.

This is in preparation to refactoring this code area.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
---
 arch/s390/include/asm/barrier.h | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

Comments

Peter Zijlstra Jan. 4, 2016, 1:20 p.m. UTC | #1
On Thu, Dec 31, 2015 at 09:06:30PM +0200, Michael S. Tsirkin wrote:
> On s390 read_barrier_depends, smp_read_barrier_depends
> smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
> asm-generic variants exactly. Drop the local definitions and pull in
> asm-generic/barrier.h instead.
> 
> This is in preparation to refactoring this code area.
> 
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> Acked-by: Arnd Bergmann <arnd@arndb.de>
> ---
>  arch/s390/include/asm/barrier.h | 10 ++--------
>  1 file changed, 2 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
> index 7ffd0b1..c358c31 100644
> --- a/arch/s390/include/asm/barrier.h
> +++ b/arch/s390/include/asm/barrier.h
> @@ -30,14 +30,6 @@
>  #define smp_rmb()			rmb()
>  #define smp_wmb()			wmb()
>  
> -#define read_barrier_depends()		do { } while (0)
> -#define smp_read_barrier_depends()	do { } while (0)
> -
> -#define smp_mb__before_atomic()		smp_mb()
> -#define smp_mb__after_atomic()		smp_mb()

As per:

  lkml.kernel.org/r/20150921112252.3c2937e1@mschwide

s390 should change this to barrier() instead of smp_mb() and hence
should not use the generic versions.
Martin Schwidefsky Jan. 4, 2016, 3:03 p.m. UTC | #2
On Mon, 4 Jan 2016 14:20:42 +0100
Peter Zijlstra <peterz@infradead.org> wrote:

> On Thu, Dec 31, 2015 at 09:06:30PM +0200, Michael S. Tsirkin wrote:
> > On s390 read_barrier_depends, smp_read_barrier_depends
> > smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
> > asm-generic variants exactly. Drop the local definitions and pull in
> > asm-generic/barrier.h instead.
> > 
> > This is in preparation to refactoring this code area.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > Acked-by: Arnd Bergmann <arnd@arndb.de>
> > ---
> >  arch/s390/include/asm/barrier.h | 10 ++--------
> >  1 file changed, 2 insertions(+), 8 deletions(-)
> > 
> > diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
> > index 7ffd0b1..c358c31 100644
> > --- a/arch/s390/include/asm/barrier.h
> > +++ b/arch/s390/include/asm/barrier.h
> > @@ -30,14 +30,6 @@
> >  #define smp_rmb()			rmb()
> >  #define smp_wmb()			wmb()
> >  
> > -#define read_barrier_depends()		do { } while (0)
> > -#define smp_read_barrier_depends()	do { } while (0)
> > -
> > -#define smp_mb__before_atomic()		smp_mb()
> > -#define smp_mb__after_atomic()		smp_mb()
> 
> As per:
> 
>   lkml.kernel.org/r/20150921112252.3c2937e1@mschwide
> 
> s390 should change this to barrier() instead of smp_mb() and hence
> should not use the generic versions.
 
Yes, we wanted to simplify this. Thanks for the reminder, I'll queue
a patch.
Michael S. Tsirkin Jan. 4, 2016, 8:34 p.m. UTC | #3
On Mon, Jan 04, 2016 at 02:20:42PM +0100, Peter Zijlstra wrote:
> On Thu, Dec 31, 2015 at 09:06:30PM +0200, Michael S. Tsirkin wrote:
> > On s390 read_barrier_depends, smp_read_barrier_depends
> > smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
> > asm-generic variants exactly. Drop the local definitions and pull in
> > asm-generic/barrier.h instead.
> > 
> > This is in preparation to refactoring this code area.
> > 
> > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > Acked-by: Arnd Bergmann <arnd@arndb.de>
> > ---
> >  arch/s390/include/asm/barrier.h | 10 ++--------
> >  1 file changed, 2 insertions(+), 8 deletions(-)
> > 
> > diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
> > index 7ffd0b1..c358c31 100644
> > --- a/arch/s390/include/asm/barrier.h
> > +++ b/arch/s390/include/asm/barrier.h
> > @@ -30,14 +30,6 @@
> >  #define smp_rmb()			rmb()
> >  #define smp_wmb()			wmb()
> >  
> > -#define read_barrier_depends()		do { } while (0)
> > -#define smp_read_barrier_depends()	do { } while (0)
> > -
> > -#define smp_mb__before_atomic()		smp_mb()
> > -#define smp_mb__after_atomic()		smp_mb()
> 
> As per:
> 
>   lkml.kernel.org/r/20150921112252.3c2937e1@mschwide
> 
> s390 should change this to barrier() instead of smp_mb() and hence
> should not use the generic versions.

Thanks Peter!

OK so I will just rename this to __smp_mb__before_atomic and
__smp_mb__after_atomic but keep them around.

I'm not changing these - that's best left to s390 maintainers.

Should I add a TODO comment to change them to barrier so
we don't forget?
Michael S. Tsirkin Jan. 4, 2016, 8:42 p.m. UTC | #4
On Mon, Jan 04, 2016 at 04:03:39PM +0100, Martin Schwidefsky wrote:
> On Mon, 4 Jan 2016 14:20:42 +0100
> Peter Zijlstra <peterz@infradead.org> wrote:
> 
> > On Thu, Dec 31, 2015 at 09:06:30PM +0200, Michael S. Tsirkin wrote:
> > > On s390 read_barrier_depends, smp_read_barrier_depends
> > > smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
> > > asm-generic variants exactly. Drop the local definitions and pull in
> > > asm-generic/barrier.h instead.
> > > 
> > > This is in preparation to refactoring this code area.
> > > 
> > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > > Acked-by: Arnd Bergmann <arnd@arndb.de>
> > > ---
> > >  arch/s390/include/asm/barrier.h | 10 ++--------
> > >  1 file changed, 2 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
> > > index 7ffd0b1..c358c31 100644
> > > --- a/arch/s390/include/asm/barrier.h
> > > +++ b/arch/s390/include/asm/barrier.h
> > > @@ -30,14 +30,6 @@
> > >  #define smp_rmb()			rmb()
> > >  #define smp_wmb()			wmb()
> > >  
> > > -#define read_barrier_depends()		do { } while (0)
> > > -#define smp_read_barrier_depends()	do { } while (0)
> > > -
> > > -#define smp_mb__before_atomic()		smp_mb()
> > > -#define smp_mb__after_atomic()		smp_mb()
> > 
> > As per:
> > 
> >   lkml.kernel.org/r/20150921112252.3c2937e1@mschwide
> > 
> > s390 should change this to barrier() instead of smp_mb() and hence
> > should not use the generic versions.
>  
> Yes, we wanted to simplify this. Thanks for the reminder, I'll queue
> a patch.

Could you base on my patchset maybe, to avoid conflicts,
and I'll merge it?
Or if it's just replacing these 2 with barrier() I can do this
myself easily.

> -- 
> blue skies,
>    Martin.
> 
> "Reality continues to ruin my life." - Calvin.
Martin Schwidefsky Jan. 5, 2016, 8:03 a.m. UTC | #5
On Mon, 4 Jan 2016 22:42:44 +0200
"Michael S. Tsirkin" <mst@redhat.com> wrote:

> On Mon, Jan 04, 2016 at 04:03:39PM +0100, Martin Schwidefsky wrote:
> > On Mon, 4 Jan 2016 14:20:42 +0100
> > Peter Zijlstra <peterz@infradead.org> wrote:
> > 
> > > On Thu, Dec 31, 2015 at 09:06:30PM +0200, Michael S. Tsirkin wrote:
> > > > On s390 read_barrier_depends, smp_read_barrier_depends
> > > > smp_store_mb(), smp_mb__before_atomic and smp_mb__after_atomic match the
> > > > asm-generic variants exactly. Drop the local definitions and pull in
> > > > asm-generic/barrier.h instead.
> > > > 
> > > > This is in preparation to refactoring this code area.
> > > > 
> > > > Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> > > > Acked-by: Arnd Bergmann <arnd@arndb.de>
> > > > ---
> > > >  arch/s390/include/asm/barrier.h | 10 ++--------
> > > >  1 file changed, 2 insertions(+), 8 deletions(-)
> > > > 
> > > > diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
> > > > index 7ffd0b1..c358c31 100644
> > > > --- a/arch/s390/include/asm/barrier.h
> > > > +++ b/arch/s390/include/asm/barrier.h
> > > > @@ -30,14 +30,6 @@
> > > >  #define smp_rmb()			rmb()
> > > >  #define smp_wmb()			wmb()
> > > >  
> > > > -#define read_barrier_depends()		do { } while (0)
> > > > -#define smp_read_barrier_depends()	do { } while (0)
> > > > -
> > > > -#define smp_mb__before_atomic()		smp_mb()
> > > > -#define smp_mb__after_atomic()		smp_mb()
> > > 
> > > As per:
> > > 
> > >   lkml.kernel.org/r/20150921112252.3c2937e1@mschwide
> > > 
> > > s390 should change this to barrier() instead of smp_mb() and hence
> > > should not use the generic versions.
> >  
> > Yes, we wanted to simplify this. Thanks for the reminder, I'll queue
> > a patch.
> 
> Could you base on my patchset maybe, to avoid conflicts,
> and I'll merge it?
> Or if it's just replacing these 2 with barrier() I can do this
> myself easily.

Probably the easiest solution if you do the patch yourself and
include it in your patch set.
diff mbox

Patch

diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h
index 7ffd0b1..c358c31 100644
--- a/arch/s390/include/asm/barrier.h
+++ b/arch/s390/include/asm/barrier.h
@@ -30,14 +30,6 @@ 
 #define smp_rmb()			rmb()
 #define smp_wmb()			wmb()
 
-#define read_barrier_depends()		do { } while (0)
-#define smp_read_barrier_depends()	do { } while (0)
-
-#define smp_mb__before_atomic()		smp_mb()
-#define smp_mb__after_atomic()		smp_mb()
-
-#define smp_store_mb(var, value)	do { WRITE_ONCE(var, value); smp_mb(); } while (0)
-
 #define smp_store_release(p, v)						\
 do {									\
 	compiletime_assert_atomic_type(*p);				\
@@ -53,4 +45,6 @@  do {									\
 	___p1;								\
 })
 
+#include <asm-generic/barrier.h>
+
 #endif /* __ASM_BARRIER_H */