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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/asm-generic/cmpxchg-local.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/asm-generic/cmpxchg-local.h')
-rw-r--r--kernel/include/asm-generic/cmpxchg-local.h67
1 files changed, 67 insertions, 0 deletions
diff --git a/kernel/include/asm-generic/cmpxchg-local.h b/kernel/include/asm-generic/cmpxchg-local.h
new file mode 100644
index 000000000..70bef7891
--- /dev/null
+++ b/kernel/include/asm-generic/cmpxchg-local.h
@@ -0,0 +1,67 @@
+#ifndef __ASM_GENERIC_CMPXCHG_LOCAL_H
+#define __ASM_GENERIC_CMPXCHG_LOCAL_H
+
+#include <linux/types.h>
+#include <linux/irqflags.h>
+
+extern unsigned long wrong_size_cmpxchg(volatile void *ptr)
+ __noreturn;
+
+/*
+ * Generic version of __cmpxchg_local (disables interrupts). Takes an unsigned
+ * long parameter, supporting various types of architectures.
+ */
+static inline unsigned long __cmpxchg_local_generic(volatile void *ptr,
+ unsigned long old, unsigned long new, int size)
+{
+ unsigned long flags, prev;
+
+ /*
+ * Sanity checking, compile-time.
+ */
+ if (size == 8 && sizeof(unsigned long) != 8)
+ wrong_size_cmpxchg(ptr);
+
+ raw_local_irq_save(flags);
+ switch (size) {
+ case 1: prev = *(u8 *)ptr;
+ if (prev == old)
+ *(u8 *)ptr = (u8)new;
+ break;
+ case 2: prev = *(u16 *)ptr;
+ if (prev == old)
+ *(u16 *)ptr = (u16)new;
+ break;
+ case 4: prev = *(u32 *)ptr;
+ if (prev == old)
+ *(u32 *)ptr = (u32)new;
+ break;
+ case 8: prev = *(u64 *)ptr;
+ if (prev == old)
+ *(u64 *)ptr = (u64)new;
+ break;
+ default:
+ wrong_size_cmpxchg(ptr);
+ }
+ raw_local_irq_restore(flags);
+ return prev;
+}
+
+/*
+ * Generic version of __cmpxchg64_local. Takes an u64 parameter.
+ */
+static inline u64 __cmpxchg64_local_generic(volatile void *ptr,
+ u64 old, u64 new)
+{
+ u64 prev;
+ unsigned long flags;
+
+ raw_local_irq_save(flags);
+ prev = *(u64 *)ptr;
+ if (prev == old)
+ *(u64 *)ptr = new;
+ raw_local_irq_restore(flags);
+ return prev;
+}
+
+#endif