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| author | David S. Miller <davem@davemloft.net> | 2010-02-28 19:23:06 -0800 |
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| committer | David S. Miller <davem@davemloft.net> | 2010-02-28 19:23:06 -0800 |
| commit | 47871889c601d8199c51a4086f77eebd77c29b0b (patch) | |
| tree | 40cdcac3bff0ee40cc33dcca61d0577cdf965f77 /arch/x86/lib/rwsem_64.S | |
| parent | c16cc0b464b8876cfd57ce1c1dbcb6f9a6a0bce3 (diff) | |
| parent | 30ff056c42c665b9ea535d8515890857ae382540 (diff) | |
| download | op-kernel-dev-47871889c601d8199c51a4086f77eebd77c29b0b.zip op-kernel-dev-47871889c601d8199c51a4086f77eebd77c29b0b.tar.gz | |
Merge branch 'master' of /home/davem/src/GIT/linux-2.6/
Conflicts:
drivers/firmware/iscsi_ibft.c
Diffstat (limited to 'arch/x86/lib/rwsem_64.S')
| -rw-r--r-- | arch/x86/lib/rwsem_64.S | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/x86/lib/rwsem_64.S b/arch/x86/lib/rwsem_64.S new file mode 100644 index 0000000..15acecf --- /dev/null +++ b/arch/x86/lib/rwsem_64.S @@ -0,0 +1,81 @@ +/* + * x86-64 rwsem wrappers + * + * This interfaces the inline asm code to the slow-path + * C routines. We need to save the call-clobbered regs + * that the asm does not mark as clobbered, and move the + * argument from %rax to %rdi. + * + * NOTE! We don't need to save %rax, because the functions + * will always return the semaphore pointer in %rax (which + * is also the input argument to these helpers) + * + * The following can clobber %rdx because the asm clobbers it: + * call_rwsem_down_write_failed + * call_rwsem_wake + * but %rdi, %rsi, %rcx, %r8-r11 always need saving. + */ + +#include <linux/linkage.h> +#include <asm/rwlock.h> +#include <asm/alternative-asm.h> +#include <asm/frame.h> +#include <asm/dwarf2.h> + +#define save_common_regs \ + pushq %rdi; \ + pushq %rsi; \ + pushq %rcx; \ + pushq %r8; \ + pushq %r9; \ + pushq %r10; \ + pushq %r11 + +#define restore_common_regs \ + popq %r11; \ + popq %r10; \ + popq %r9; \ + popq %r8; \ + popq %rcx; \ + popq %rsi; \ + popq %rdi + +/* Fix up special calling conventions */ +ENTRY(call_rwsem_down_read_failed) + save_common_regs + pushq %rdx + movq %rax,%rdi + call rwsem_down_read_failed + popq %rdx + restore_common_regs + ret + ENDPROC(call_rwsem_down_read_failed) + +ENTRY(call_rwsem_down_write_failed) + save_common_regs + movq %rax,%rdi + call rwsem_down_write_failed + restore_common_regs + ret + ENDPROC(call_rwsem_down_write_failed) + +ENTRY(call_rwsem_wake) + decw %dx /* do nothing if still outstanding active readers */ + jnz 1f + save_common_regs + movq %rax,%rdi + call rwsem_wake + restore_common_regs +1: ret + ENDPROC(call_rwsem_wake) + +/* Fix up special calling conventions */ +ENTRY(call_rwsem_downgrade_wake) + save_common_regs + pushq %rdx + movq %rax,%rdi + call rwsem_downgrade_wake + popq %rdx + restore_common_regs + ret + ENDPROC(call_rwsem_downgrade_wake) |
