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Groups > linux.kernel > #1587282
| From | Stafford Horne <shorne@gmail.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v4 08/24] openrisc: add cmpxchg and xchg implementations |
| Date | 2017-02-24 05:40 +0100 |
| Message-ID | <tefPH-3gU-15@gated-at.bofh.it> (permalink) |
| References | <tefPH-3gU-5@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
From: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
Optimized version that make use of the l.lwa and l.swa atomic instruction
pair.
Most openrisc cores provide these instructions now, if not available
emulation is provided.
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
[shorne@gmail.com: remove OPENRISC_HAVE_INST_LWA_SWA config suggesed by
Alan Cox https://lkml.org/lkml/2014/7/23/666]
[shorne@gmail.com: fixed unused calculated value compiler warning in
define cmpxchg]
Signed-off-by: Stafford Horne <shorne@gmail.com>
---
arch/openrisc/include/asm/Kbuild | 2 -
arch/openrisc/include/asm/cmpxchg.h | 83 +++++++++++++++++++++++++++++++++++++
2 files changed, 83 insertions(+), 2 deletions(-)
create mode 100644 arch/openrisc/include/asm/cmpxchg.h
diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild
index 6dd177d..15e6ed5 100644
--- a/arch/openrisc/include/asm/Kbuild
+++ b/arch/openrisc/include/asm/Kbuild
@@ -10,8 +10,6 @@ generic-y += bugs.h
generic-y += cacheflush.h
generic-y += checksum.h
generic-y += clkdev.h
-generic-y += cmpxchg-local.h
-generic-y += cmpxchg.h
generic-y += cputime.h
generic-y += current.h
generic-y += device.h
diff --git a/arch/openrisc/include/asm/cmpxchg.h b/arch/openrisc/include/asm/cmpxchg.h
new file mode 100644
index 0000000..5fcb9ac
--- /dev/null
+++ b/arch/openrisc/include/asm/cmpxchg.h
@@ -0,0 +1,83 @@
+/*
+ * Copyright (C) 2014 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2. This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+#ifndef __ASM_OPENRISC_CMPXCHG_H
+#define __ASM_OPENRISC_CMPXCHG_H
+
+#include <linux/types.h>
+
+/*
+ * This function doesn't exist, so you'll get a linker error
+ * if something tries to do an invalid cmpxchg().
+ */
+extern void __cmpxchg_called_with_bad_pointer(void);
+
+#define __HAVE_ARCH_CMPXCHG 1
+
+static inline unsigned long
+__cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size)
+{
+ if (size != 4) {
+ __cmpxchg_called_with_bad_pointer();
+ return old;
+ }
+
+ __asm__ __volatile__(
+ "1: l.lwa %0, 0(%1) \n"
+ " l.sfeq %0, %2 \n"
+ " l.bnf 2f \n"
+ " l.nop \n"
+ " l.swa 0(%1), %3 \n"
+ " l.bnf 1b \n"
+ " l.nop \n"
+ "2: \n"
+ : "=&r"(old)
+ : "r"(ptr), "r"(old), "r"(new)
+ : "cc", "memory");
+
+ return old;
+}
+
+#define cmpxchg(ptr, o, n) \
+ ({ \
+ (__typeof__(*(ptr))) __cmpxchg((ptr), \
+ (unsigned long)(o), \
+ (unsigned long)(n), \
+ sizeof(*(ptr))); \
+ })
+
+/*
+ * This function doesn't exist, so you'll get a linker error if
+ * something tries to do an invalidly-sized xchg().
+ */
+extern void __xchg_called_with_bad_pointer(void);
+
+static inline unsigned long __xchg(unsigned long val, volatile void *ptr,
+ int size)
+{
+ if (size != 4) {
+ __xchg_called_with_bad_pointer();
+ return val;
+ }
+
+ __asm__ __volatile__(
+ "1: l.lwa %0, 0(%1) \n"
+ " l.swa 0(%1), %2 \n"
+ " l.bnf 1b \n"
+ " l.nop \n"
+ : "=&r"(val)
+ : "r"(ptr), "r"(val)
+ : "cc", "memory");
+
+ return val;
+}
+
+#define xchg(ptr, with) \
+ ((typeof(*(ptr)))__xchg((unsigned long)(with), (ptr), sizeof(*(ptr))))
+
+#endif /* __ASM_OPENRISC_CMPXCHG_H */
--
2.9.3
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[PATCH v4 00/24] OpenRISC patches for 4.11 Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 23/24] openrisc: Export ioremap symbols used by modules Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 13/24] openrisc: Initial support for the idle state Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Tobias Klauser <tklauser@distanz.ch> - 2017-02-24 16:00 +0100
Re: [PATCH v4 18/24] scripts/checkstack.pl: Add openrisc support Stafford Horne <shorne@gmail.com> - 2017-02-24 20:40 +0100
[PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200 option Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200 option Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
Re: [PATCH v4 22/24] arch/openrisc/lib/memcpy.c: use correct OR1200 option Stafford Horne <shorne@gmail.com> - 2017-02-24 21:00 +0100
[PATCH v4 08/24] openrisc: add cmpxchg and xchg implementations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 20/24] openrisc: entry: Fix delay slot detection Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 20/24] openrisc: entry: Fix delay slot detection Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
Re: [PATCH v4 20/24] openrisc: entry: Fix delay slot detection Stafford Horne <shorne@gmail.com> - 2017-02-24 21:20 +0100
[PATCH v4 09/24] openrisc: add optimized atomic operations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 04/24] openrisc: head: use THREAD_SIZE instead of magic constant Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 07/24] openrisc: add atomic bitops Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 07/24] openrisc: add atomic bitops Peter Zijlstra <peterz@infradead.org> - 2017-02-24 12:00 +0100
Re: [PATCH v4 07/24] openrisc: add atomic bitops Stafford Horne <shorne@gmail.com> - 2017-02-24 20:30 +0100
[PATCH v4 11/24] openrisc: remove unnecessary stddef.h include Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 01/24] openrisc: use SPARSE_IRQ Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 21/24] openrisc: head: Move init strings to rodata section Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata section Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
Re: [PATCH v4 21/24] openrisc: head: Move init strings to rodata section Stafford Horne <shorne@gmail.com> - 2017-02-24 21:20 +0100
[PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:00 +0100
Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> - 2017-02-24 12:10 +0100
Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Jonas Bonn <jonas@southpole.se> - 2017-02-24 13:50 +0100
Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> - 2017-02-24 15:00 +0100
Re: [PATCH v4 05/24] openrisc: head: refactor out tlb flush into it's own function Stafford Horne <shorne@gmail.com> - 2017-02-24 20:30 +0100
[PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Jonas Bonn <jonas@southpole.se> - 2017-02-24 11:10 +0100
Re: [PATCH v4 24/24] openrisc: head: Init r0 to 0 on start Stafford Horne <shorne@gmail.com> - 2017-02-24 20:40 +0100
[PATCH v4 17/24] MAINTAINERS: Add the openrisc official repository Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 12/24] openrisc: Fix the bitmask for the unit present register Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
Re: [PATCH v4 06/24] openrisc: add l.lwa/l.swa emulation Stafford Horne <shorne@gmail.com> - 2017-02-24 21:00 +0100
[PATCH v4 10/24] openrisc: add futex_atomic_* implementations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 03/24] openrisc: tlb miss handler optimizations Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
[PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Stafford Horne <shorne@gmail.com> - 2017-02-24 05:40 +0100
Re: [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Jonas Bonn <jonas@southpole.se> - 2017-02-24 10:50 +0100
Re: [PATCH v4 19/24] openrisc: entry: Whitespace and comment cleanups Stafford Horne <shorne@gmail.com> - 2017-02-24 21:40 +0100
[PATCH v4 15/24] openrisc: Add optimized memcpy routine Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100
[PATCH v4 16/24] openrisc: Add .gitignore Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100
[PATCH v4 14/24] openrisc: Add optimized memset Stafford Horne <shorne@gmail.com> - 2017-02-24 05:50 +0100
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