diff options
Diffstat (limited to 'arch/tile/kernel/ftrace.c')
-rw-r--r-- | arch/tile/kernel/ftrace.c | 239 |
1 files changed, 0 insertions, 239 deletions
diff --git a/arch/tile/kernel/ftrace.c b/arch/tile/kernel/ftrace.c deleted file mode 100644 index b827a418b155..000000000000 --- a/arch/tile/kernel/ftrace.c +++ /dev/null @@ -1,239 +0,0 @@ -/* - * Copyright 2012 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. - * - * TILE-Gx specific ftrace support - */ - -#include <linux/ftrace.h> -#include <linux/uaccess.h> - -#include <asm/cacheflush.h> -#include <asm/ftrace.h> -#include <asm/sections.h> -#include <asm/insn.h> - -#include <arch/opcode.h> - -#ifdef CONFIG_DYNAMIC_FTRACE - -static int machine_stopped __read_mostly; - -int ftrace_arch_code_modify_prepare(void) -{ - machine_stopped = 1; - return 0; -} - -int ftrace_arch_code_modify_post_process(void) -{ - flush_icache_range(0, CHIP_L1I_CACHE_SIZE()); - machine_stopped = 0; - return 0; -} - -/* - * Put { move r10, lr; jal ftrace_caller } in a bundle, this lets dynamic - * tracer just add one cycle overhead to every kernel function when disabled. - */ -static unsigned long ftrace_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); - } - - /* - * Also put { move r10, lr; jal ftrace_stub } in a bundle, which - * is used to replace the instruction in address ftrace_call. - */ - if (addr == FTRACE_ADDR || addr == (unsigned long)ftrace_stub) { - /* opcode: or r10, lr, zero */ - opcode_x0 = - create_Dest_X0(10) | - create_SrcA_X0(TREG_LR) | - create_SrcB_X0(TREG_ZERO) | - create_RRROpcodeExtension_X0(OR_RRR_0_OPCODE_X0) | - create_Opcode_X0(RRR_0_OPCODE_X0); - } else { - /* 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; -} - -static unsigned long ftrace_nop_replace(struct dyn_ftrace *rec) -{ - return NOP(); -} - -static unsigned long ftrace_call_replace(unsigned long pc, unsigned long addr) -{ - return ftrace_gen_branch(pc, addr, true); -} - -static int ftrace_modify_code(unsigned long pc, unsigned long old, - unsigned long new) -{ - unsigned long pc_wr; - - /* Check if the address is in kernel text space and module space. */ - if (!kernel_text_address(pc)) - return -EINVAL; - - /* Operate on writable kernel text mapping. */ - pc_wr = ktext_writable_addr(pc); - - if (probe_kernel_write((void *)pc_wr, &new, MCOUNT_INSN_SIZE)) - return -EPERM; - - smp_wmb(); - - if (!machine_stopped && num_online_cpus() > 1) - flush_icache_range(pc, pc + MCOUNT_INSN_SIZE); - - return 0; -} - -int ftrace_update_ftrace_func(ftrace_func_t func) -{ - unsigned long pc, old; - unsigned long new; - int ret; - - pc = (unsigned long)&ftrace_call; - memcpy(&old, &ftrace_call, MCOUNT_INSN_SIZE); - new = ftrace_call_replace(pc, (unsigned long)func); - - ret = ftrace_modify_code(pc, old, new); - - return ret; -} - -int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr) -{ - unsigned long new, old; - unsigned long ip = rec->ip; - - old = ftrace_nop_replace(rec); - new = ftrace_call_replace(ip, addr); - - return ftrace_modify_code(rec->ip, old, new); -} - -int ftrace_make_nop(struct module *mod, - struct dyn_ftrace *rec, unsigned long addr) -{ - unsigned long ip = rec->ip; - unsigned long old; - unsigned long new; - int ret; - - old = ftrace_call_replace(ip, addr); - new = ftrace_nop_replace(rec); - ret = ftrace_modify_code(ip, old, new); - - return ret; -} - -int __init ftrace_dyn_arch_init(void) -{ - return 0; -} -#endif /* CONFIG_DYNAMIC_FTRACE */ - -#ifdef CONFIG_FUNCTION_GRAPH_TRACER -void prepare_ftrace_return(unsigned long *parent, unsigned long self_addr, - unsigned long frame_pointer) -{ - unsigned long return_hooker = (unsigned long) &return_to_handler; - struct ftrace_graph_ent trace; - unsigned long old; - int err; - - if (unlikely(atomic_read(¤t->tracing_graph_pause))) - return; - - old = *parent; - *parent = return_hooker; - - err = ftrace_push_return_trace(old, self_addr, &trace.depth, - frame_pointer, NULL); - if (err == -EBUSY) { - *parent = old; - return; - } - - trace.func = self_addr; - - /* Only trace if the calling function expects to */ - if (!ftrace_graph_entry(&trace)) { - current->curr_ret_stack--; - *parent = old; - } -} - -#ifdef CONFIG_DYNAMIC_FTRACE -extern unsigned long ftrace_graph_call; - -static int __ftrace_modify_caller(unsigned long *callsite, - void (*func) (void), bool enable) -{ - unsigned long caller_fn = (unsigned long) func; - unsigned long pc = (unsigned long) callsite; - unsigned long branch = ftrace_gen_branch(pc, caller_fn, false); - unsigned long nop = NOP(); - unsigned long old = enable ? nop : branch; - unsigned long new = enable ? branch : nop; - - return ftrace_modify_code(pc, old, new); -} - -static int ftrace_modify_graph_caller(bool enable) -{ - int ret; - - ret = __ftrace_modify_caller(&ftrace_graph_call, - ftrace_graph_caller, - enable); - - return ret; -} - -int ftrace_enable_ftrace_graph_caller(void) -{ - return ftrace_modify_graph_caller(true); -} - -int ftrace_disable_ftrace_graph_caller(void) -{ - return ftrace_modify_graph_caller(false); -} -#endif /* CONFIG_DYNAMIC_FTRACE */ -#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ |