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authorIngo Molnar <mingo@kernel.org>2012-04-14 13:18:27 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-14 13:19:04 +0200
commit6ac1ef482d7ae0c690f1640bf6eb818ff9a2d91e (patch)
tree021cc9f6b477146fcebe6f3be4752abfa2ba18a9 /arch/avr32/include/asm/cmpxchg.h
parent682968e0c425c60f0dde37977e5beb2b12ddc4cc (diff)
parenta385ec4f11bdcf81af094c03e2444ee9b7fad2e5 (diff)
Merge branch 'perf/core' into perf/uprobes
Merge in latest upstream (and the latest perf development tree), to prepare for tooling changes, and also to pick up v3.4 MM changes that the uprobes code needs to take care of. Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/avr32/include/asm/cmpxchg.h')
-rw-r--r--arch/avr32/include/asm/cmpxchg.h117
1 files changed, 117 insertions, 0 deletions
diff --git a/arch/avr32/include/asm/cmpxchg.h b/arch/avr32/include/asm/cmpxchg.h
new file mode 100644
index 000000000000..962a6aeab787
--- /dev/null
+++ b/arch/avr32/include/asm/cmpxchg.h
@@ -0,0 +1,117 @@
+/*
+ * Atomic operations that C can't guarantee us. Useful for
+ * resource counting etc.
+ *
+ * But use these as seldom as possible since they are slower than
+ * regular operations.
+ *
+ * Copyright (C) 2004-2006 Atmel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#ifndef __ASM_AVR32_CMPXCHG_H
+#define __ASM_AVR32_CMPXCHG_H
+
+#define xchg(ptr,x) \
+ ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr))))
+
+extern void __xchg_called_with_bad_pointer(void);
+
+static inline unsigned long xchg_u32(u32 val, volatile u32 *m)
+{
+ u32 ret;
+
+ asm volatile("xchg %[ret], %[m], %[val]"
+ : [ret] "=&r"(ret), "=m"(*m)
+ : "m"(*m), [m] "r"(m), [val] "r"(val)
+ : "memory");
+ return ret;
+}
+
+static inline unsigned long __xchg(unsigned long x,
+ volatile void *ptr,
+ int size)
+{
+ switch(size) {
+ case 4:
+ return xchg_u32(x, ptr);
+ default:
+ __xchg_called_with_bad_pointer();
+ return x;
+ }
+}
+
+static inline unsigned long __cmpxchg_u32(volatile int *m, unsigned long old,
+ unsigned long new)
+{
+ __u32 ret;
+
+ asm volatile(
+ "1: ssrf 5\n"
+ " ld.w %[ret], %[m]\n"
+ " cp.w %[ret], %[old]\n"
+ " brne 2f\n"
+ " stcond %[m], %[new]\n"
+ " brne 1b\n"
+ "2:\n"
+ : [ret] "=&r"(ret), [m] "=m"(*m)
+ : "m"(m), [old] "ir"(old), [new] "r"(new)
+ : "memory", "cc");
+ return ret;
+}
+
+extern unsigned long __cmpxchg_u64_unsupported_on_32bit_kernels(
+ volatile int * m, unsigned long old, unsigned long new);
+#define __cmpxchg_u64 __cmpxchg_u64_unsupported_on_32bit_kernels
+
+/* 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)
+{
+ switch (size) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+ case 8:
+ return __cmpxchg_u64(ptr, old, new);
+ }
+
+ __cmpxchg_called_with_bad_pointer();
+ return old;
+}
+
+#define cmpxchg(ptr, old, new) \
+ ((typeof(*(ptr)))__cmpxchg((ptr), (unsigned long)(old), \
+ (unsigned long)(new), \
+ sizeof(*(ptr))))
+
+#include <asm-generic/cmpxchg-local.h>
+
+static inline unsigned long __cmpxchg_local(volatile void *ptr,
+ unsigned long old,
+ unsigned long new, int size)
+{
+ switch (size) {
+ case 4:
+ return __cmpxchg_u32(ptr, old, new);
+ default:
+ return __cmpxchg_local_generic(ptr, old, new, size);
+ }
+
+ return old;
+}
+
+#define cmpxchg_local(ptr, old, new) \
+ ((typeof(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(old), \
+ (unsigned long)(new), \
+ sizeof(*(ptr))))
+
+#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n))
+
+#endif /* __ASM_AVR32_CMPXCHG_H */