| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1519291469-5702-1-git-send-email-parri.andrea@gmail.com>
Date: Thu, 22 Feb 2018 10:24:29 +0100
From: Andrea Parri <parri.andrea@...il.com>
To: Ingo Molnar <mingo@...nel.org>,
Peter Zijlstra <peterz@...radead.org>
Cc: Andrea Parri <parri.andrea@...il.com>,
"Paul E . McKenney" <paulmck@...ux.vnet.ibm.com>,
Alan Stern <stern@...land.harvard.edu>,
Ivan Kokshaysky <ink@...assic.park.msu.ru>,
Matt Turner <mattst88@...il.com>,
Richard Henderson <rth@...ddle.net>,
linux-alpha@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [PATCH 1/2] locking/xchg/alpha: Use smp_mb() in place of __ASM__MB
Replace each occurrence of __ASM__MB with a (trailing) smp_mb() in
xchg(), cmpxchg(), and remove the now unused __ASM__MB definitions;
this improves readability, with no additional synchronization cost.
Suggested-by: Will Deacon <will.deacon@....com>
Signed-off-by: Andrea Parri <parri.andrea@...il.com>
Cc: Peter Zijlstra <peterz@...radead.org>
Cc: Paul E. McKenney <paulmck@...ux.vnet.ibm.com>
Cc: Alan Stern <stern@...land.harvard.edu>
Cc: Ivan Kokshaysky <ink@...assic.park.msu.ru>
Cc: Matt Turner <mattst88@...il.com>
Cc: Richard Henderson <rth@...ddle.net>
Cc: linux-alpha@...r.kernel.org
Cc: linux-kernel@...r.kernel.org
---
arch/alpha/include/asm/cmpxchg.h | 6 ------
arch/alpha/include/asm/xchg.h | 16 ++++++++--------
2 files changed, 8 insertions(+), 14 deletions(-)
diff --git a/arch/alpha/include/asm/cmpxchg.h b/arch/alpha/include/asm/cmpxchg.h
index 46ebf14aed4e5..8a2b331e43feb 100644
--- a/arch/alpha/include/asm/cmpxchg.h
+++ b/arch/alpha/include/asm/cmpxchg.h
@@ -6,7 +6,6 @@
* Atomic exchange routines.
*/
-#define __ASM__MB
#define ____xchg(type, args...) __xchg ## type ## _local(args)
#define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args)
#include <asm/xchg.h>
@@ -33,10 +32,6 @@
cmpxchg_local((ptr), (o), (n)); \
})
-#ifdef CONFIG_SMP
-#undef __ASM__MB
-#define __ASM__MB "\tmb\n"
-#endif
#undef ____xchg
#undef ____cmpxchg
#define ____xchg(type, args...) __xchg ##type(args)
@@ -64,7 +59,6 @@
cmpxchg((ptr), (o), (n)); \
})
-#undef __ASM__MB
#undef ____cmpxchg
#endif /* _ALPHA_CMPXCHG_H */
diff --git a/arch/alpha/include/asm/xchg.h b/arch/alpha/include/asm/xchg.h
index e2660866ce972..e1facf6fc2446 100644
--- a/arch/alpha/include/asm/xchg.h
+++ b/arch/alpha/include/asm/xchg.h
@@ -28,12 +28,12 @@ ____xchg(_u8, volatile char *m, unsigned long val)
" or %1,%2,%2\n"
" stq_c %2,0(%3)\n"
" beq %2,2f\n"
- __ASM__MB
".subsection 2\n"
"2: br 1b\n"
".previous"
: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
: "r" ((long)m), "1" (val) : "memory");
+ smp_mb();
return ret;
}
@@ -52,12 +52,12 @@ ____xchg(_u16, volatile short *m, unsigned long val)
" or %1,%2,%2\n"
" stq_c %2,0(%3)\n"
" beq %2,2f\n"
- __ASM__MB
".subsection 2\n"
"2: br 1b\n"
".previous"
: "=&r" (ret), "=&r" (val), "=&r" (tmp), "=&r" (addr64)
: "r" ((long)m), "1" (val) : "memory");
+ smp_mb();
return ret;
}
@@ -72,12 +72,12 @@ ____xchg(_u32, volatile int *m, unsigned long val)
" bis $31,%3,%1\n"
" stl_c %1,%2\n"
" beq %1,2f\n"
- __ASM__MB
".subsection 2\n"
"2: br 1b\n"
".previous"
: "=&r" (val), "=&r" (dummy), "=m" (*m)
: "rI" (val), "m" (*m) : "memory");
+ smp_mb();
return val;
}
@@ -92,12 +92,12 @@ ____xchg(_u64, volatile long *m, unsigned long val)
" bis $31,%3,%1\n"
" stq_c %1,%2\n"
" beq %1,2f\n"
- __ASM__MB
".subsection 2\n"
"2: br 1b\n"
".previous"
: "=&r" (val), "=&r" (dummy), "=m" (*m)
: "rI" (val), "m" (*m) : "memory");
+ smp_mb();
return val;
}
@@ -150,12 +150,12 @@ ____cmpxchg(_u8, volatile char *m, unsigned char old, unsigned char new)
" stq_c %2,0(%4)\n"
" beq %2,3f\n"
"2:\n"
- __ASM__MB
".subsection 2\n"
"3: br 1b\n"
".previous"
: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
: "r" ((long)m), "Ir" (old), "1" (new) : "memory");
+ smp_mb();
return prev;
}
@@ -177,12 +177,12 @@ ____cmpxchg(_u16, volatile short *m, unsigned short old, unsigned short new)
" stq_c %2,0(%4)\n"
" beq %2,3f\n"
"2:\n"
- __ASM__MB
".subsection 2\n"
"3: br 1b\n"
".previous"
: "=&r" (prev), "=&r" (new), "=&r" (tmp), "=&r" (cmp), "=&r" (addr64)
: "r" ((long)m), "Ir" (old), "1" (new) : "memory");
+ smp_mb();
return prev;
}
@@ -200,12 +200,12 @@ ____cmpxchg(_u32, volatile int *m, int old, int new)
" stl_c %1,%2\n"
" beq %1,3f\n"
"2:\n"
- __ASM__MB
".subsection 2\n"
"3: br 1b\n"
".previous"
: "=&r"(prev), "=&r"(cmp), "=m"(*m)
: "r"((long) old), "r"(new), "m"(*m) : "memory");
+ smp_mb();
return prev;
}
@@ -223,12 +223,12 @@ ____cmpxchg(_u64, volatile long *m, unsigned long old, unsigned long new)
" stq_c %1,%2\n"
" beq %1,3f\n"
"2:\n"
- __ASM__MB
".subsection 2\n"
"3: br 1b\n"
".previous"
: "=&r"(prev), "=&r"(cmp), "=m"(*m)
: "r"((long) old), "r"(new), "m"(*m) : "memory");
+ smp_mb();
return prev;
}
--
2.7.4
Powered by blists - more mailing lists