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-rw-r--r--arch/x86/lib/thunk_64.S45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/x86/lib/thunk_64.S b/arch/x86/lib/thunk_64.S
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+++ b/arch/x86/lib/thunk_64.S
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+/*
+ * Save registers before calling assembly functions. This avoids
+ * disturbance of register allocation in some inline assembly constructs.
+ * Copyright 2001,2002 by Andi Kleen, SuSE Labs.
+ * Added trace_hardirqs callers - Copyright 2007 Steven Rostedt, Red Hat, Inc.
+ * Subject to the GNU public license, v.2. No warranty of any kind.
+ */
+#include <linux/linkage.h>
+#include <asm/dwarf2.h>
+#include <asm/calling.h>
+
+ /* rdi: arg1 ... normal C conventions. rax is saved/restored. */
+ .macro THUNK name, func, put_ret_addr_in_rdi=0
+ .globl \name
+\name:
+ CFI_STARTPROC
+
+ /* this one pushes 9 elems, the next one would be %rIP */
+ SAVE_ARGS
+
+ .if \put_ret_addr_in_rdi
+ movq_cfi_restore 9*8, rdi
+ .endif
+
+ call \func
+ jmp restore
+ CFI_ENDPROC
+ .endm
+
+#ifdef CONFIG_TRACE_IRQFLAGS
+ THUNK trace_hardirqs_on_thunk,trace_hardirqs_on_caller,1
+ THUNK trace_hardirqs_off_thunk,trace_hardirqs_off_caller,1
+#endif
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+ THUNK lockdep_sys_exit_thunk,lockdep_sys_exit
+#endif
+
+ /* SAVE_ARGS below is used only for the .cfi directives it contains. */
+ CFI_STARTPROC
+ SAVE_ARGS
+restore:
+ RESTORE_ARGS
+ ret
+ CFI_ENDPROC