Commit d2f47dab authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc/code-patching: Inline create_branch() 



create_branch() is a good candidate for inlining because:
- Flags can be folded in.
- Range tests are likely to be already done.

Hence reducing the create_branch() to only a set of instructions.

So inline it.

It improves ftrace activation by 10%.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/69851cc9a7bf8f03d025e6d29e165f2d0bd3bb6e.1652074503.git.christophe.leroy@csgroup.eu
parent a1facd25

arch/powerpc/include/asm/code-patching.h

+20 −2
Original line number Diff line number Diff line
@@ -51,8 +51,26 @@ static inline bool is_offset_in_cond_branch_range(long offset) 
	return offset >= -0x8000 && offset <= 0x7fff && !(offset & 0x3);

}



int create_branch(ppc_inst_t *instr, const u32 *addr,

		  unsigned long target, int flags);

static inline int create_branch(ppc_inst_t *instr, const u32 *addr,

				unsigned long target, int flags)

{

	long offset;



	*instr = ppc_inst(0);

	offset = target;

	if (! (flags & BRANCH_ABSOLUTE))

		offset = offset - (unsigned long)addr;



	/* Check we can represent the target in the instruction format */

	if (!is_offset_in_branch_range(offset))

		return 1;



	/* Mask out the flags and target, so they don't step on each other. */

	*instr = ppc_inst(0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC));



	return 0;

}



int create_cond_branch(ppc_inst_t *instr, const u32 *addr,

		       unsigned long target, int flags);

int patch_branch(u32 *addr, unsigned long target, int flags);

arch/powerpc/lib/code-patching.c

+0 −20
Original line number Diff line number Diff line
@@ -236,26 +236,6 @@ bool is_conditional_branch(ppc_inst_t instr) 
}

NOKPROBE_SYMBOL(is_conditional_branch);



int create_branch(ppc_inst_t *instr, const u32 *addr,

		  unsigned long target, int flags)

{

	long offset;



	*instr = ppc_inst(0);

	offset = target;

	if (! (flags & BRANCH_ABSOLUTE))

		offset = offset - (unsigned long)addr;



	/* Check we can represent the target in the instruction format */

	if (!is_offset_in_branch_range(offset))

		return 1;



	/* Mask out the flags and target, so they don't step on each other. */

	*instr = ppc_inst(0x48000000 | (flags & 0x3) | (offset & 0x03FFFFFC));



	return 0;

}



int create_cond_branch(ppc_inst_t *instr, const u32 *addr,

		       unsigned long target, int flags)

{