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Date: Thu, 24 Mar 2022 15:29:55 +0100 From: Christophe Leroy <christophe.leroy@...roup.eu> To: "Naveen N . Rao" <naveen.n.rao@...ux.vnet.ibm.com>, Steven Rostedt <rostedt@...dmis.org>, Ingo Molnar <mingo@...hat.com>, Benjamin Herrenschmidt <benh@...nel.crashing.org>, Paul Mackerras <paulus@...ba.org>, Michael Ellerman <mpe@...erman.id.au> Cc: Christophe Leroy <christophe.leroy@...roup.eu>, linux-kernel@...r.kernel.org, linuxppc-dev@...ts.ozlabs.org Subject: [PATCH v1 05/22] 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: Christophe Leroy <christophe.leroy@...roup.eu> --- arch/powerpc/include/asm/code-patching.h | 22 ++++++++++++++++++++-- arch/powerpc/lib/code-patching.c | 20 -------------------- 2 files changed, 20 insertions(+), 22 deletions(-) diff --git a/arch/powerpc/include/asm/code-patching.h b/arch/powerpc/include/asm/code-patching.h index e7c5df50cb4e..4260e89f62b1 100644 --- a/arch/powerpc/include/asm/code-patching.h +++ b/arch/powerpc/include/asm/code-patching.h @@ -49,8 +49,26 @@ 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); diff --git a/arch/powerpc/lib/code-patching.c b/arch/powerpc/lib/code-patching.c index 58262c7e447c..7adbdb05fee7 100644 --- a/arch/powerpc/lib/code-patching.c +++ b/arch/powerpc/lib/code-patching.c @@ -230,26 +230,6 @@ 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) { -- 2.35.1
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