ftrace/x86: Get rid of ftrace_caller_setup (f1ab00af) · Commits · 戴 / test

arch/x86/kernel/mcount_64.S

+42 −29

Original line number	Diff line number	Diff line
		@@ -54,7 +54,15 @@
		* be saved in the locations that pt_regs has them in.
		*/

		/* @added: the amount of stack added before calling this */
		/*
		* @added: the amount of stack added before calling this
		*
		* After this is called, the following registers contain:
		*
		* %rdi - holds the address that called the trampoline
		* %rsi - holds the parent function (traced function's return address)
		* %rdx - holds the original %rbp
		*/
		.macro save_mcount_regs added=0

		/* Always save the original rbp */
		@@ -101,9 +109,24 @@
		movq MCOUNT_REG_SIZE-8(%rsp), %rdx
		movq %rdx, RBP(%rsp)

		/* Copy the parent address into %rsi (second parameter) */
		#ifdef CC_USING_FENTRY
		movq MCOUNT_REG_SIZE+8+\added(%rsp), %rsi
		#else
		/* %rdx contains original %rbp */
		movq 8(%rdx), %rsi
		#endif

		/* Move RIP to its proper location */
		movq MCOUNT_REG_SIZE+\added(%rsp), %rdi
		movq %rdi, RIP(%rsp)

		/*
		* Now %rdi (the first parameter) has the return address of
		* where ftrace_call returns. But the callbacks expect the
		* the address of the call itself.
		*/
		subq $MCOUNT_INSN_SIZE, %rdi
		.endm

		.macro restore_mcount_regs
		@@ -122,28 +145,6 @@

		.endm

		/* skip is set if stack has been adjusted */
		.macro ftrace_caller_setup trace_label added=0
		save_mcount_regs \added

		/* Save this location */
		GLOBAL(\trace_label)
		/* Load the ftrace_ops into the 3rd parameter */
		movq function_trace_op(%rip), %rdx

		/* %rdi already has %rip from the save_mcount_regs macro */
		subq $MCOUNT_INSN_SIZE, %rdi
		/* Load the parent_ip into the second parameter */
		#ifdef CC_USING_FENTRY
		movq MCOUNT_REG_SIZE+8+\added(%rsp), %rsi
		#else
		/* Need to grab the original %rbp */
		movq RBP(%rsp), %rsi
		/* Now parent address is 8 above original %rbp */
		movq 8(%rsi), %rsi
		#endif
		.endm

		#ifdef CONFIG_DYNAMIC_FTRACE

		ENTRY(function_hook)
		@@ -151,7 +152,13 @@ ENTRY(function_hook)
		END(function_hook)

		ENTRY(ftrace_caller)
		ftrace_caller_setup ftrace_caller_op_ptr
		/* save_mcount_regs fills in first two parameters */
		save_mcount_regs

		GLOBAL(ftrace_caller_op_ptr)
		/* Load the ftrace_ops into the 3rd parameter */
		movq function_trace_op(%rip), %rdx

		/* regs go into 4th parameter (but make it NULL) */
		movq $0, %rcx

		@@ -182,7 +189,12 @@ ENTRY(ftrace_regs_caller)
		pushfq

		/* added 8 bytes to save flags */
		ftrace_caller_setup ftrace_regs_caller_op_ptr 8
		save_mcount_regs 8
		/* save_mcount_regs fills in first two parameters */

		GLOBAL(ftrace_regs_caller_op_ptr)
		/* Load the ftrace_ops into the 3rd parameter */
		movq function_trace_op(%rip), %rdx

		/* Save the rest of pt_regs */
		movq %r15, R15(%rsp)
		@@ -263,7 +275,8 @@ GLOBAL(ftrace_stub)
		retq

		trace:
		ftrace_caller_setup ftrace_caller_op_ptr
		/* save_mcount_regs fills in first two parameters */
		save_mcount_regs

		call *ftrace_trace_function

		@@ -276,16 +289,16 @@ END(function_hook)

		#ifdef CONFIG_FUNCTION_GRAPH_TRACER
		ENTRY(ftrace_graph_caller)
		/* Saves rbp into %rdx */
		save_mcount_regs

		#ifdef CC_USING_FENTRY
		leaq MCOUNT_REG_SIZE+8(%rsp), %rdi
		movq $0, %rdx /* No framepointers needed */
		#else
		/* Need to grab the original %rbp */
		movq RBP(%rsp), %rdx
		/* Now parent address is 8 above original %rbp */
		/* Save address of the return address of traced function */
		leaq 8(%rdx), %rdi
		/* ftrace does sanity checks against frame pointers */
		movq (%rdx), %rdx
		#endif
		movq RIP(%rsp), %rsi

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