Commit e434b08b authored by Mark Brown's avatar Mark Brown Committed by Catalin Marinas
Browse files

arm64: ftrace: Correct annotation of ftrace_caller assembly 



In an effort to clarify and simplify the annotation of assembly
functions new macros have been introduced. These replace ENTRY and
ENDPROC with two different annotations for normal functions and those
with unusual calling conventions.

The patchable function entry versions of ftrace_*_caller don't follow the
usual AAPCS rules, pushing things onto the stack which they don't clean up,
and therefore should be annotated as code rather than functions.

Signed-off-by: default avatarMark Brown <broonie@kernel.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent e2d591d2

arch/arm64/kernel/entry-ftrace.S

+8 −8
Original line number Diff line number Diff line
@@ -75,17 +75,17 @@ 
	add	x29, sp, #S_STACKFRAME

	.endm



ENTRY(ftrace_regs_caller)

SYM_CODE_START(ftrace_regs_caller)

	ftrace_regs_entry	1

	b	ftrace_common

ENDPROC(ftrace_regs_caller)

SYM_CODE_END(ftrace_regs_caller)



ENTRY(ftrace_caller)

SYM_CODE_START(ftrace_caller)

	ftrace_regs_entry	0

	b	ftrace_common

ENDPROC(ftrace_caller)

SYM_CODE_END(ftrace_caller)



ENTRY(ftrace_common)

SYM_CODE_START(ftrace_common)

	sub	x0, x30, #AARCH64_INSN_SIZE	// ip (callsite's BL insn)

	mov	x1, x9				// parent_ip (callsite's LR)

	ldr_l	x2, function_trace_op		// op
@@ -122,17 +122,17 @@ ftrace_common_return: 
	add	sp, sp, #S_FRAME_SIZE + 16



	ret	x9

ENDPROC(ftrace_common)

SYM_CODE_END(ftrace_common)



#ifdef CONFIG_FUNCTION_GRAPH_TRACER

ENTRY(ftrace_graph_caller)

SYM_CODE_START(ftrace_graph_caller)

	ldr	x0, [sp, #S_PC]

	sub	x0, x0, #AARCH64_INSN_SIZE	// ip (callsite's BL insn)

	add	x1, sp, #S_LR			// parent_ip (callsite's LR)

	ldr	x2, [sp, #S_FRAME_SIZE]	   	// parent fp (callsite's FP)

	bl	prepare_ftrace_return

	b	ftrace_common_return

ENDPROC(ftrace_graph_caller)

SYM_CODE_END(ftrace_graph_caller)

#endif



#else /* CONFIG_DYNAMIC_FTRACE_WITH_REGS */

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