From 65a792e84f25d1436698f999224b2cf5d7594546 Mon Sep 17 00:00:00 2001 From: Zhigang Lu Date: Wed, 30 Sep 2015 10:11:45 +0800 Subject: [PATCH] tile/jump_label: add jump label support for TILE-Gx Add the arch-specific code to support jump label for TILE-Gx. This code shares NOP instruction with ftrace, so we move it to a common header file. Reviewed-by: Chris Metcalf Signed-off-by: Zhigang Lu Signed-off-by: Chris Metcalf --- arch/tile/Kconfig | 1 + arch/tile/include/asm/insn.h | 59 +++++++++++++++++++++++++++++++++++ arch/tile/include/asm/jump_label.h | 58 ++++++++++++++++++++++++++++++++++ arch/tile/kernel/Makefile | 1 + arch/tile/kernel/ftrace.c | 11 +------ arch/tile/kernel/jump_label.c | 64 ++++++++++++++++++++++++++++++++++++++ 6 files changed, 184 insertions(+), 10 deletions(-) create mode 100644 arch/tile/include/asm/insn.h create mode 100644 arch/tile/include/asm/jump_label.h create mode 100644 arch/tile/kernel/jump_label.c diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig index 106c21b..49be476 100644 --- a/arch/tile/Kconfig +++ b/arch/tile/Kconfig @@ -143,6 +143,7 @@ config TILEGX select HAVE_KRETPROBES select HAVE_ARCH_KGDB select ARCH_SUPPORTS_ATOMIC_RMW + select HAVE_ARCH_JUMP_LABEL config TILEPRO def_bool !TILEGX diff --git a/arch/tile/include/asm/insn.h b/arch/tile/include/asm/insn.h new file mode 100644 index 0000000..f78ba5c --- /dev/null +++ b/arch/tile/include/asm/insn.h @@ -0,0 +1,59 @@ +/* + * Copyright 2015 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ +#ifndef __ASM_TILE_INSN_H +#define __ASM_TILE_INSN_H + +#include + +static inline tilegx_bundle_bits NOP(void) +{ + return create_UnaryOpcodeExtension_X0(FNOP_UNARY_OPCODE_X0) | + create_RRROpcodeExtension_X0(UNARY_RRR_0_OPCODE_X0) | + create_Opcode_X0(RRR_0_OPCODE_X0) | + create_UnaryOpcodeExtension_X1(NOP_UNARY_OPCODE_X1) | + create_RRROpcodeExtension_X1(UNARY_RRR_0_OPCODE_X1) | + create_Opcode_X1(RRR_0_OPCODE_X1); +} + +static inline tilegx_bundle_bits tilegx_gen_branch(unsigned long pc, + unsigned long addr, + bool link) +{ + tilegx_bundle_bits opcode_x0, opcode_x1; + long pcrel_by_instr = (addr - pc) >> TILEGX_LOG2_BUNDLE_SIZE_IN_BYTES; + + if (link) { + /* opcode: jal addr */ + opcode_x1 = + create_Opcode_X1(JUMP_OPCODE_X1) | + create_JumpOpcodeExtension_X1(JAL_JUMP_OPCODE_X1) | + create_JumpOff_X1(pcrel_by_instr); + } else { + /* opcode: j addr */ + opcode_x1 = + create_Opcode_X1(JUMP_OPCODE_X1) | + create_JumpOpcodeExtension_X1(J_JUMP_OPCODE_X1) | + create_JumpOff_X1(pcrel_by_instr); + } + + /* opcode: fnop */ + opcode_x0 = + create_UnaryOpcodeExtension_X0(FNOP_UNARY_OPCODE_X0) | + create_RRROpcodeExtension_X0(UNARY_RRR_0_OPCODE_X0) | + create_Opcode_X0(RRR_0_OPCODE_X0); + + return opcode_x1 | opcode_x0; +} + +#endif /* __ASM_TILE_INSN_H */ diff --git a/arch/tile/include/asm/jump_label.h b/arch/tile/include/asm/jump_label.h new file mode 100644 index 0000000..cde7573 --- /dev/null +++ b/arch/tile/include/asm/jump_label.h @@ -0,0 +1,58 @@ +/* + * Copyright 2015 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#ifndef _ASM_TILE_JUMP_LABEL_H +#define _ASM_TILE_JUMP_LABEL_H + +#include + +#define JUMP_LABEL_NOP_SIZE TILE_BUNDLE_SIZE_IN_BYTES + +static __always_inline bool arch_static_branch(struct static_key *key, + bool branch) +{ + asm_volatile_goto("1:\n\t" + "nop" "\n\t" + ".pushsection __jump_table, \"aw\"\n\t" + ".quad 1b, %l[l_yes], %0 + %1 \n\t" + ".popsection\n\t" + : : "i" (key), "i" (branch) : : l_yes); + return false; +l_yes: + return true; +} + +static __always_inline bool arch_static_branch_jump(struct static_key *key, + bool branch) +{ + asm_volatile_goto("1:\n\t" + "j %l[l_yes]" "\n\t" + ".pushsection __jump_table, \"aw\"\n\t" + ".quad 1b, %l[l_yes], %0 + %1 \n\t" + ".popsection\n\t" + : : "i" (key), "i" (branch) : : l_yes); + return false; +l_yes: + return true; +} + +typedef u64 jump_label_t; + +struct jump_entry { + jump_label_t code; + jump_label_t target; + jump_label_t key; +}; + +#endif /* _ASM_TILE_JUMP_LABEL_H */ diff --git a/arch/tile/kernel/Makefile b/arch/tile/kernel/Makefile index 21f77bf..09936d0 100644 --- a/arch/tile/kernel/Makefile +++ b/arch/tile/kernel/Makefile @@ -32,5 +32,6 @@ obj-$(CONFIG_TILE_HVGLUE_TRACE) += hvglue_trace.o obj-$(CONFIG_FUNCTION_TRACER) += ftrace.o mcount_64.o obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_KGDB) += kgdb.o +obj-$(CONFIG_JUMP_LABEL) += jump_label.o obj-y += vdso/ diff --git a/arch/tile/kernel/ftrace.c b/arch/tile/kernel/ftrace.c index 4180ccdf..4a57208 100644 --- a/arch/tile/kernel/ftrace.c +++ b/arch/tile/kernel/ftrace.c @@ -20,21 +20,12 @@ #include #include #include +#include #include #ifdef CONFIG_DYNAMIC_FTRACE -static inline tilegx_bundle_bits NOP(void) -{ - return create_UnaryOpcodeExtension_X0(FNOP_UNARY_OPCODE_X0) | - create_RRROpcodeExtension_X0(UNARY_RRR_0_OPCODE_X0) | - create_Opcode_X0(RRR_0_OPCODE_X0) | - create_UnaryOpcodeExtension_X1(NOP_UNARY_OPCODE_X1) | - create_RRROpcodeExtension_X1(UNARY_RRR_0_OPCODE_X1) | - create_Opcode_X1(RRR_0_OPCODE_X1); -} - static int machine_stopped __read_mostly; int ftrace_arch_code_modify_prepare(void) diff --git a/arch/tile/kernel/jump_label.c b/arch/tile/kernel/jump_label.c new file mode 100644 index 0000000..07802d5 --- /dev/null +++ b/arch/tile/kernel/jump_label.c @@ -0,0 +1,64 @@ +/* + * Copyright 2015 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + * + * jump label TILE-Gx support + */ + +#include +#include +#include +#include +#include + +#include +#include + +#ifdef HAVE_JUMP_LABEL + +static void __jump_label_transform(struct jump_entry *e, + enum jump_label_type type) +{ + tilegx_bundle_bits opcode; + /* Operate on writable kernel text mapping. */ + unsigned long pc_wr = ktext_writable_addr(e->code); + + if (type == JUMP_LABEL_JMP) + opcode = tilegx_gen_branch(e->code, e->target, false); + else + opcode = NOP(); + + *(tilegx_bundle_bits *)pc_wr = opcode; + /* Make sure that above mem writes were issued towards the memory. */ + smp_wmb(); +} + +void arch_jump_label_transform(struct jump_entry *e, + enum jump_label_type type) +{ + get_online_cpus(); + mutex_lock(&text_mutex); + + __jump_label_transform(e, type); + flush_icache_range(e->code, e->code + sizeof(tilegx_bundle_bits)); + + mutex_unlock(&text_mutex); + put_online_cpus(); +} + +__init_or_module void arch_jump_label_transform_static(struct jump_entry *e, + enum jump_label_type type) +{ + __jump_label_transform(e, type); +} + +#endif /* HAVE_JUMP_LABEL */ -- 2.7.4