| Message ID | 1438528264-714-1-git-send-email-andreyknvl@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Sun, Aug 02, 2015 at 05:11:04PM +0200, Andrey Konovalov wrote: > Replace ACCESS_ONCE() macro in smp_store_release() and smp_load_acquire() > with WRITE_ONCE() and READ_ONCE() on x86, arm, arm64, ia64, metag, mips, > powerpc, s390, sparc and asm-generic since ACCESS_ONCE does not work > reliably on non-scalar types. > > WRITE_ONCE() and READ_ONCE() were introduced in the commits 230fa253df63 > ("kernel: Provide READ_ONCE and ASSIGN_ONCE") and 43239cbe79fc ("kernel: > Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)"). > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Thanks!
On Sun, 2015-08-02 at 17:11 +0200, Andrey Konovalov wrote: > Replace ACCESS_ONCE() macro in smp_store_release() and smp_load_acquire() > with WRITE_ONCE() and READ_ONCE() on x86, arm, arm64, ia64, metag, mips, > powerpc, s390, sparc and asm-generic since ACCESS_ONCE does not work > reliably on non-scalar types. > > WRITE_ONCE() and READ_ONCE() were introduced in the commits 230fa253df63 > ("kernel: Provide READ_ONCE and ASSIGN_ONCE") and 43239cbe79fc ("kernel: > Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)"). > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Acked-by: Davidlohr Bueso <dbueso@suse.de>
On Sun, 2015-08-02 at 17:11 +0200, Andrey Konovalov wrote: > Replace ACCESS_ONCE() macro in smp_store_release() and smp_load_acquire() > with WRITE_ONCE() and READ_ONCE() on x86, arm, arm64, ia64, metag, mips, > powerpc, s390, sparc and asm-generic since ACCESS_ONCE does not work > reliably on non-scalar types. .. and there are no restrictions on the argument to smp_load_acquire(), so it may be a non-scalar type. Though from a quick grep it looks like no one is doing that at the moment? > WRITE_ONCE() and READ_ONCE() were introduced in the commits 230fa253df63 > ("kernel: Provide READ_ONCE and ASSIGN_ONCE") and 43239cbe79fc ("kernel: > Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)"). > > Signed-off-by: Andrey Konovalov <andreyknvl@google.com> > --- > Changed in v2: > - Other archs besides x86. > > arch/powerpc/include/asm/barrier.h | 4 ++-- > diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h > index 51ccc72..0eca6ef 100644 > --- a/arch/powerpc/include/asm/barrier.h > +++ b/arch/powerpc/include/asm/barrier.h > @@ -76,12 +76,12 @@ > do { \ > compiletime_assert_atomic_type(*p); \ > smp_lwsync(); \ > - ACCESS_ONCE(*p) = (v); \ > + WRITE_ONCE(*p, v); \ > } while (0) > > #define smp_load_acquire(p) \ > ({ \ > - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ > + typeof(*p) ___p1 = READ_ONCE(*p); \ > compiletime_assert_atomic_type(*p); \ > smp_lwsync(); \ > ___p1; \ Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc) cheers
On Sun, Aug 02, 2015 at 05:11:04PM +0200, Andrey Konovalov wrote: > diff --git a/arch/mips/include/asm/barrier.h b/arch/mips/include/asm/barrier.h > index 7ecba84..752e0b8 100644 > --- a/arch/mips/include/asm/barrier.h > +++ b/arch/mips/include/asm/barrier.h > @@ -133,12 +133,12 @@ > do { \ > compiletime_assert_atomic_type(*p); \ > smp_mb(); \ > - ACCESS_ONCE(*p) = (v); \ > + WRITE_ONCE(*p, v); \ > } while (0) > > #define smp_load_acquire(p) \ > ({ \ > - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ > + typeof(*p) ___p1 = READ_ONCE(*p); \ > compiletime_assert_atomic_type(*p); \ > smp_mb(); \ > ___p1; \ Acked-by: Ralf Baechle <ralf@linux-mips.org> Ralf
diff --git a/arch/arm/include/asm/barrier.h b/arch/arm/include/asm/barrier.h index 6c2327e..7039357 100644 --- a/arch/arm/include/asm/barrier.h +++ b/arch/arm/include/asm/barrier.h @@ -67,12 +67,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \ diff --git a/arch/arm64/include/asm/barrier.h b/arch/arm64/include/asm/barrier.h index 0fa47c4..ef93b20 100644 --- a/arch/arm64/include/asm/barrier.h +++ b/arch/arm64/include/asm/barrier.h @@ -44,12 +44,12 @@ do { \ compiletime_assert_atomic_type(*p); \ barrier(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ barrier(); \ ___p1; \ diff --git a/arch/ia64/include/asm/barrier.h b/arch/ia64/include/asm/barrier.h index 843ba43..df896a1 100644 --- a/arch/ia64/include/asm/barrier.h +++ b/arch/ia64/include/asm/barrier.h @@ -66,12 +66,12 @@ do { \ compiletime_assert_atomic_type(*p); \ barrier(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ barrier(); \ ___p1; \ diff --git a/arch/metag/include/asm/barrier.h b/arch/metag/include/asm/barrier.h index 5a696e5..172b7e5 100644 --- a/arch/metag/include/asm/barrier.h +++ b/arch/metag/include/asm/barrier.h @@ -90,12 +90,12 @@ static inline void fence(void) do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \ diff --git a/arch/mips/include/asm/barrier.h b/arch/mips/include/asm/barrier.h index 7ecba84..752e0b8 100644 --- a/arch/mips/include/asm/barrier.h +++ b/arch/mips/include/asm/barrier.h @@ -133,12 +133,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \ diff --git a/arch/powerpc/include/asm/barrier.h b/arch/powerpc/include/asm/barrier.h index 51ccc72..0eca6ef 100644 --- a/arch/powerpc/include/asm/barrier.h +++ b/arch/powerpc/include/asm/barrier.h @@ -76,12 +76,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_lwsync(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_lwsync(); \ ___p1; \ diff --git a/arch/s390/include/asm/barrier.h b/arch/s390/include/asm/barrier.h index e6f8615..d48fe01 100644 --- a/arch/s390/include/asm/barrier.h +++ b/arch/s390/include/asm/barrier.h @@ -42,12 +42,12 @@ do { \ compiletime_assert_atomic_type(*p); \ barrier(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ barrier(); \ ___p1; \ diff --git a/arch/sparc/include/asm/barrier_64.h b/arch/sparc/include/asm/barrier_64.h index 809941e..14a9286 100644 --- a/arch/sparc/include/asm/barrier_64.h +++ b/arch/sparc/include/asm/barrier_64.h @@ -60,12 +60,12 @@ do { __asm__ __volatile__("ba,pt %%xcc, 1f\n\t" \ do { \ compiletime_assert_atomic_type(*p); \ barrier(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ barrier(); \ ___p1; \ diff --git a/arch/x86/include/asm/barrier.h b/arch/x86/include/asm/barrier.h index e51a8f8..d2bcfbe 100644 --- a/arch/x86/include/asm/barrier.h +++ b/arch/x86/include/asm/barrier.h @@ -57,12 +57,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \ @@ -74,12 +74,12 @@ do { \ do { \ compiletime_assert_atomic_type(*p); \ barrier(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ barrier(); \ ___p1; \ diff --git a/include/asm-generic/barrier.h b/include/asm-generic/barrier.h index 55e3abc..b42afad 100644 --- a/include/asm-generic/barrier.h +++ b/include/asm-generic/barrier.h @@ -108,12 +108,12 @@ do { \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ - ACCESS_ONCE(*p) = (v); \ + WRITE_ONCE(*p, v); \ } while (0) #define smp_load_acquire(p) \ ({ \ - typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + typeof(*p) ___p1 = READ_ONCE(*p); \ compiletime_assert_atomic_type(*p); \ smp_mb(); \ ___p1; \
Replace ACCESS_ONCE() macro in smp_store_release() and smp_load_acquire() with WRITE_ONCE() and READ_ONCE() on x86, arm, arm64, ia64, metag, mips, powerpc, s390, sparc and asm-generic since ACCESS_ONCE does not work reliably on non-scalar types. WRITE_ONCE() and READ_ONCE() were introduced in the commits 230fa253df63 ("kernel: Provide READ_ONCE and ASSIGN_ONCE") and 43239cbe79fc ("kernel: Change ASSIGN_ONCE(val, x) to WRITE_ONCE(x, val)"). Signed-off-by: Andrey Konovalov <andreyknvl@google.com> --- Changed in v2: - Other archs besides x86. arch/arm/include/asm/barrier.h | 4 ++-- arch/arm64/include/asm/barrier.h | 4 ++-- arch/ia64/include/asm/barrier.h | 4 ++-- arch/metag/include/asm/barrier.h | 4 ++-- arch/mips/include/asm/barrier.h | 4 ++-- arch/powerpc/include/asm/barrier.h | 4 ++-- arch/s390/include/asm/barrier.h | 4 ++-- arch/sparc/include/asm/barrier_64.h | 4 ++-- arch/x86/include/asm/barrier.h | 8 ++++---- include/asm-generic/barrier.h | 4 ++-- 10 files changed, 22 insertions(+), 22 deletions(-)