X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fmips%2Fkernel%2Fprocess.c;fp=arch%2Fmips%2Fkernel%2Fprocess.c;h=405fef3c11152de3618ca46dfd43d021242ea94d;hb=97bf2856c6014879bd04983a3e9dfcdac1e7fe85;hp=092679c2dca9b83bd3e66503d83413daf29853d7;hpb=76828883507a47dae78837ab5dec5a5b4513c667;p=linux-2.6.git diff --git a/arch/mips/kernel/process.c b/arch/mips/kernel/process.c index 092679c2d..405fef3c1 100644 --- a/arch/mips/kernel/process.c +++ b/arch/mips/kernel/process.c @@ -8,7 +8,6 @@ * Copyright (C) 1999, 2000 Silicon Graphics, Inc. * Copyright (C) 2004 Thiemo Seufer */ -#include #include #include #include @@ -41,6 +40,11 @@ #include #include #include +#include +#ifdef CONFIG_MIPS_MT_SMTC +#include +extern void smtc_idle_loop_hook(void); +#endif /* CONFIG_MIPS_MT_SMTC */ /* * The idle thread. There's no useful work to be done, so just try to conserve @@ -51,26 +55,22 @@ ATTRIB_NORET void cpu_idle(void) { /* endless idle loop with no priority at all */ while (1) { - while (!need_resched()) + while (!need_resched()) { +#ifdef CONFIG_MIPS_MT_SMTC + smtc_idle_loop_hook(); +#endif /* CONFIG_MIPS_MT_SMTC */ if (cpu_wait) (*cpu_wait)(); + } preempt_enable_no_resched(); schedule(); preempt_disable(); } } -extern void do_signal(struct pt_regs *regs); -extern void do_signal32(struct pt_regs *regs); - /* * Native o32 and N64 ABI without DSP ASE */ -extern int setup_frame(struct k_sigaction * ka, struct pt_regs *regs, - int signr, sigset_t *set); -extern int setup_rt_frame(struct k_sigaction * ka, struct pt_regs *regs, - int signr, sigset_t *set, siginfo_t *info); - struct mips_abi mips_abi = { .do_signal = do_signal, #ifdef CONFIG_TRAD_SIGNALS @@ -83,11 +83,6 @@ struct mips_abi mips_abi = { /* * o32 compatibility on 64-bit kernels, without DSP ASE */ -extern int setup_frame_32(struct k_sigaction * ka, struct pt_regs *regs, - int signr, sigset_t *set); -extern int setup_rt_frame_32(struct k_sigaction * ka, struct pt_regs *regs, - int signr, sigset_t *set, siginfo_t *info); - struct mips_abi mips_abi_32 = { .do_signal = do_signal32, .setup_frame = setup_frame_32, @@ -99,9 +94,6 @@ struct mips_abi mips_abi_32 = { /* * N32 on 64-bit kernels, without DSP ASE */ -extern int setup_rt_frame_n32(struct k_sigaction * ka, struct pt_regs *regs, - int signr, sigset_t *set, siginfo_t *info); - struct mips_abi mips_abi_n32 = { .do_signal = do_signal, .setup_rt_frame = setup_rt_frame_n32 @@ -123,7 +115,7 @@ void start_thread(struct pt_regs * regs, unsigned long pc, unsigned long sp) status |= KU_USER; regs->cp0_status = status; clear_used_math(); - lose_fpu(); + clear_fpu_owner(); if (cpu_has_dsp) __init_dsp(); regs->cp0_epc = pc; @@ -193,6 +185,17 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, childregs->cp0_status &= ~(ST0_CU2|ST0_CU1); clear_tsk_thread_flag(p, TIF_USEDFPU); +#ifdef CONFIG_MIPS_MT_FPAFF + /* + * FPU affinity support is cleaner if we track the + * user-visible CPU affinity from the very beginning. + * The generic cpus_allowed mask will already have + * been copied from the parent before copy_thread + * is invoked. + */ + p->thread.user_cpus_allowed = p->cpus_allowed; +#endif /* CONFIG_MIPS_MT_FPAFF */ + if (clone_flags & CLONE_SETTLS) ti->tp_value = regs->regs[7]; @@ -268,107 +271,109 @@ long kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) #endif /* Ok, create the new process.. */ - return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, ®s, 0, NULL, NULL); + return do_fork(flags | CLONE_VM | CLONE_UNTRACED | CLONE_KTHREAD, + 0, ®s, 0, NULL, NULL); } -static struct mips_frame_info { - void *func; - unsigned long func_size; - int frame_size; - int pc_offset; -} *schedule_frame, mfinfo[64]; -static int mfinfo_num; +/* + * + */ +struct mips_frame_info { + void *func; + unsigned long func_size; + int frame_size; + int pc_offset; +}; -static int __init get_frame_info(struct mips_frame_info *info) +static inline int is_ra_save_ins(union mips_instruction *ip) { - int i; - void *func = info->func; - union mips_instruction *ip = (union mips_instruction *)func; + /* sw / sd $ra, offset($sp) */ + return (ip->i_format.opcode == sw_op || ip->i_format.opcode == sd_op) && + ip->i_format.rs == 29 && + ip->i_format.rt == 31; +} + +static inline int is_jal_jalr_jr_ins(union mips_instruction *ip) +{ + if (ip->j_format.opcode == jal_op) + return 1; + if (ip->r_format.opcode != spec_op) + return 0; + return ip->r_format.func == jalr_op || ip->r_format.func == jr_op; +} + +static inline int is_sp_move_ins(union mips_instruction *ip) +{ + /* addiu/daddiu sp,sp,-imm */ + if (ip->i_format.rs != 29 || ip->i_format.rt != 29) + return 0; + if (ip->i_format.opcode == addiu_op || ip->i_format.opcode == daddiu_op) + return 1; + return 0; +} + +static int get_frame_info(struct mips_frame_info *info) +{ + union mips_instruction *ip = info->func; + unsigned max_insns = info->func_size / sizeof(union mips_instruction); + unsigned i; + info->pc_offset = -1; info->frame_size = 0; - for (i = 0; i < 128; i++, ip++) { - /* if jal, jalr, jr, stop. */ - if (ip->j_format.opcode == jal_op || - (ip->r_format.opcode == spec_op && - (ip->r_format.func == jalr_op || - ip->r_format.func == jr_op))) - break; - if (info->func_size && i >= info->func_size / 4) + if (!ip) + goto err; + + if (max_insns == 0) + max_insns = 128U; /* unknown function size */ + max_insns = min(128U, max_insns); + + for (i = 0; i < max_insns; i++, ip++) { + + if (is_jal_jalr_jr_ins(ip)) break; - if ( -#ifdef CONFIG_32BIT - ip->i_format.opcode == addiu_op && -#endif -#ifdef CONFIG_64BIT - ip->i_format.opcode == daddiu_op && -#endif - ip->i_format.rs == 29 && - ip->i_format.rt == 29) { - /* addiu/daddiu sp,sp,-imm */ - if (info->frame_size) - continue; - info->frame_size = - ip->i_format.simmediate; + if (!info->frame_size) { + if (is_sp_move_ins(ip)) + info->frame_size = - ip->i_format.simmediate; + continue; } - - if ( -#ifdef CONFIG_32BIT - ip->i_format.opcode == sw_op && -#endif -#ifdef CONFIG_64BIT - ip->i_format.opcode == sd_op && -#endif - ip->i_format.rs == 29 && - ip->i_format.rt == 31) { - /* sw / sd $ra, offset($sp) */ - if (info->pc_offset != -1) - continue; + if (info->pc_offset == -1 && is_ra_save_ins(ip)) { info->pc_offset = ip->i_format.simmediate / sizeof(long); + break; } } - if (info->pc_offset == -1 || info->frame_size == 0) { - if (func == schedule) - printk("Can't analyze prologue code at %p\n", func); - info->pc_offset = -1; - info->frame_size = 0; - } - - return 0; + if (info->frame_size && info->pc_offset >= 0) /* nested */ + return 0; + if (info->pc_offset < 0) /* leaf */ + return 1; + /* prologue seems boggus... */ +err: + return -1; } +static struct mips_frame_info schedule_mfi __read_mostly; + static int __init frame_info_init(void) { - int i; + unsigned long size = 0; #ifdef CONFIG_KALLSYMS - char *modname; - char namebuf[KSYM_NAME_LEN + 1]; - unsigned long start, size, ofs; - extern char __sched_text_start[], __sched_text_end[]; - extern char __lock_text_start[], __lock_text_end[]; - - start = (unsigned long)__sched_text_start; - for (i = 0; i < ARRAY_SIZE(mfinfo); i++) { - if (start == (unsigned long)schedule) - schedule_frame = &mfinfo[i]; - if (!kallsyms_lookup(start, &size, &ofs, &modname, namebuf)) - break; - mfinfo[i].func = (void *)(start + ofs); - mfinfo[i].func_size = size; - start += size - ofs; - if (start >= (unsigned long)__lock_text_end) - break; - if (start == (unsigned long)__sched_text_end) - start = (unsigned long)__lock_text_start; - } -#else - mfinfo[0].func = schedule; - schedule_frame = &mfinfo[0]; + unsigned long ofs; + + kallsyms_lookup_size_offset((unsigned long)schedule, &size, &ofs); #endif - for (i = 0; i < ARRAY_SIZE(mfinfo) && mfinfo[i].func; i++) - get_frame_info(&mfinfo[i]); + schedule_mfi.func = schedule; + schedule_mfi.func_size = size; + + get_frame_info(&schedule_mfi); + + /* + * Without schedule() frame info, result given by + * thread_saved_pc() and get_wchan() are not reliable. + */ + if (schedule_mfi.pc_offset < 0) + printk("Can't analyze schedule() prologue at %p\n", schedule); - mfinfo_num = i; return 0; } @@ -384,55 +389,110 @@ unsigned long thread_saved_pc(struct task_struct *tsk) /* New born processes are a special case */ if (t->reg31 == (unsigned long) ret_from_fork) return t->reg31; - - if (!schedule_frame || schedule_frame->pc_offset < 0) + if (schedule_mfi.pc_offset < 0) return 0; - return ((unsigned long *)t->reg29)[schedule_frame->pc_offset]; + return ((unsigned long *)t->reg29)[schedule_mfi.pc_offset]; } -/* get_wchan - a maintenance nightmare^W^Wpain in the ass ... */ -unsigned long get_wchan(struct task_struct *p) + +#ifdef CONFIG_KALLSYMS +/* used by show_backtrace() */ +unsigned long unwind_stack(struct task_struct *task, unsigned long *sp, + unsigned long pc, unsigned long *ra) { unsigned long stack_page; - unsigned long pc; -#ifdef CONFIG_KALLSYMS - unsigned long frame; -#endif + struct mips_frame_info info; + unsigned long size, ofs; + int leaf; + extern void ret_from_irq(void); + extern void ret_from_exception(void); + + stack_page = (unsigned long)task_stack_page(task); + if (!stack_page) + return 0; - if (!p || p == current || p->state == TASK_RUNNING) + /* + * If we reached the bottom of interrupt context, + * return saved pc in pt_regs. + */ + if (pc == (unsigned long)ret_from_irq || + pc == (unsigned long)ret_from_exception) { + struct pt_regs *regs; + if (*sp >= stack_page && + *sp + sizeof(*regs) <= stack_page + THREAD_SIZE - 32) { + regs = (struct pt_regs *)*sp; + pc = regs->cp0_epc; + if (__kernel_text_address(pc)) { + *sp = regs->regs[29]; + *ra = regs->regs[31]; + return pc; + } + } return 0; + } + if (!kallsyms_lookup_size_offset(pc, &size, &ofs)) + return 0; + /* + * Return ra if an exception occured at the first instruction + */ + if (unlikely(ofs == 0)) { + pc = *ra; + *ra = 0; + return pc; + } - stack_page = (unsigned long)task_stack_page(p); - if (!stack_page || !mfinfo_num) + info.func = (void *)(pc - ofs); + info.func_size = ofs; /* analyze from start to ofs */ + leaf = get_frame_info(&info); + if (leaf < 0) return 0; - pc = thread_saved_pc(p); + if (*sp < stack_page || + *sp + info.frame_size > stack_page + THREAD_SIZE - 32) + return 0; + + if (leaf) + /* + * For some extreme cases, get_frame_info() can + * consider wrongly a nested function as a leaf + * one. In that cases avoid to return always the + * same value. + */ + pc = pc != *ra ? *ra : 0; + else + pc = ((unsigned long *)(*sp))[info.pc_offset]; + + *sp += info.frame_size; + *ra = 0; + return __kernel_text_address(pc) ? pc : 0; +} +#endif + +/* + * get_wchan - a maintenance nightmare^W^Wpain in the ass ... + */ +unsigned long get_wchan(struct task_struct *task) +{ + unsigned long pc = 0; #ifdef CONFIG_KALLSYMS - if (!in_sched_functions(pc)) - return pc; + unsigned long sp; + unsigned long ra = 0; +#endif - frame = p->thread.reg29 + schedule_frame->frame_size; - do { - int i; + if (!task || task == current || task->state == TASK_RUNNING) + goto out; + if (!task_stack_page(task)) + goto out; - if (frame < stack_page || frame > stack_page + THREAD_SIZE - 32) - return 0; + pc = thread_saved_pc(task); - for (i = mfinfo_num - 1; i >= 0; i--) { - if (pc >= (unsigned long) mfinfo[i].func) - break; - } - if (i < 0) - break; +#ifdef CONFIG_KALLSYMS + sp = task->thread.reg29 + schedule_mfi.frame_size; - pc = ((unsigned long *)frame)[mfinfo[i].pc_offset]; - if (!mfinfo[i].frame_size) - break; - frame += mfinfo[i].frame_size; - } while (in_sched_functions(pc)); + while (in_sched_functions(pc)) + pc = unwind_stack(task, &sp, pc, &ra); #endif +out: return pc; } - -EXPORT_SYMBOL(get_wchan);