X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=arch%2Fx86%2Fkernel%2Fprocess_32.c;h=14014d766cadba461c27705a0626560dc308bb70;hb=82268da1b130f763d22d04f7d016bbf6fc8815c2;hp=2b9db93710607bee99b82baf86a933d2222762f4;hpb=eee3af4a2c83a97fff107ddc445d9df6fded9ce4;p=safe%2Fjmp%2Flinux-2.6 diff --git a/arch/x86/kernel/process_32.c b/arch/x86/kernel/process_32.c index 2b9db93..14014d7 100644 --- a/arch/x86/kernel/process_32.c +++ b/arch/x86/kernel/process_32.c @@ -11,6 +11,7 @@ #include +#include #include #include #include @@ -23,7 +24,6 @@ #include #include #include -#include #include #include #include @@ -37,16 +37,19 @@ #include #include #include +#include +#include +#include +#include +#include +#include -#include #include #include -#include #include #include #include #include -#include #ifdef CONFIG_MATH_EMULATION #include #endif @@ -55,21 +58,15 @@ #include #include -#include +#include +#include +#include asmlinkage void ret_from_fork(void) __asm__("ret_from_fork"); -static int hlt_counter; - -unsigned long boot_option_idle_override = 0; -EXPORT_SYMBOL(boot_option_idle_override); - DEFINE_PER_CPU(struct task_struct *, current_task) = &init_task; EXPORT_PER_CPU_SYMBOL(current_task); -DEFINE_PER_CPU(int, cpu_number); -EXPORT_PER_CPU_SYMBOL(cpu_number); - /* * Return saved PC of a blocked thread. */ @@ -78,100 +75,12 @@ unsigned long thread_saved_pc(struct task_struct *tsk) return ((unsigned long *)tsk->thread.sp)[3]; } -/* - * Powermanagement idle function, if any.. - */ -void (*pm_idle)(void); -EXPORT_SYMBOL(pm_idle); -static DEFINE_PER_CPU(unsigned int, cpu_idle_state); - -void disable_hlt(void) -{ - hlt_counter++; -} - -EXPORT_SYMBOL(disable_hlt); - -void enable_hlt(void) -{ - hlt_counter--; -} - -EXPORT_SYMBOL(enable_hlt); - -/* - * We use this if we don't have any better - * idle routine.. - */ -void default_idle(void) -{ - if (!hlt_counter && boot_cpu_data.hlt_works_ok) { - current_thread_info()->status &= ~TS_POLLING; - /* - * TS_POLLING-cleared state must be visible before we - * test NEED_RESCHED: - */ - smp_mb(); - - local_irq_disable(); - if (!need_resched()) { - ktime_t t0, t1; - u64 t0n, t1n; - - t0 = ktime_get(); - t0n = ktime_to_ns(t0); - safe_halt(); /* enables interrupts racelessly */ - local_irq_disable(); - t1 = ktime_get(); - t1n = ktime_to_ns(t1); - sched_clock_idle_wakeup_event(t1n - t0n); - } - local_irq_enable(); - current_thread_info()->status |= TS_POLLING; - } else { - /* loop is done by the caller */ - cpu_relax(); - } -} -#ifdef CONFIG_APM_MODULE -EXPORT_SYMBOL(default_idle); -#endif - -/* - * On SMP it's slightly faster (but much more power-consuming!) - * to poll the ->work.need_resched flag instead of waiting for the - * cross-CPU IPI to arrive. Use this option with caution. - */ -static void poll_idle(void) -{ - cpu_relax(); -} - -#ifdef CONFIG_HOTPLUG_CPU -#include -/* We don't actually take CPU down, just spin without interrupts. */ -static inline void play_dead(void) -{ - /* This must be done before dead CPU ack */ - cpu_exit_clear(); - wbinvd(); - mb(); - /* Ack it */ - __get_cpu_var(cpu_state) = CPU_DEAD; - - /* - * With physical CPU hotplug, we should halt the cpu - */ - local_irq_disable(); - while (1) - halt(); -} -#else +#ifndef CONFIG_SMP static inline void play_dead(void) { BUG(); } -#endif /* CONFIG_HOTPLUG_CPU */ +#endif /* * The idle thread. There's no useful work to be @@ -183,29 +92,33 @@ void cpu_idle(void) { int cpu = smp_processor_id(); + /* + * If we're the non-boot CPU, nothing set the stack canary up + * for us. CPU0 already has it initialized but no harm in + * doing it again. This is a good place for updating it, as + * we wont ever return from this function (so the invalid + * canaries already on the stack wont ever trigger). + */ + boot_init_stack_canary(); + current_thread_info()->status |= TS_POLLING; /* endless idle loop with no priority at all */ while (1) { - tick_nohz_stop_sched_tick(); + tick_nohz_stop_sched_tick(1); while (!need_resched()) { - void (*idle)(void); - - if (__get_cpu_var(cpu_idle_state)) - __get_cpu_var(cpu_idle_state) = 0; check_pgt_cache(); rmb(); - idle = pm_idle; - - if (!idle) - idle = default_idle; if (cpu_is_offline(cpu)) play_dead(); - __get_cpu_var(irq_stat).idle_timestamp = jiffies; - idle(); + local_irq_disable(); + /* Don't trace irqs off for idle */ + stop_critical_timings(); + pm_idle(); + start_critical_timings(); } tick_nohz_restart_sched_tick(); preempt_enable_no_resched(); @@ -214,119 +127,18 @@ void cpu_idle(void) } } -static void do_nothing(void *unused) -{ -} - -void cpu_idle_wait(void) -{ - unsigned int cpu, this_cpu = get_cpu(); - cpumask_t map, tmp = current->cpus_allowed; - - set_cpus_allowed(current, cpumask_of_cpu(this_cpu)); - put_cpu(); - - cpus_clear(map); - for_each_online_cpu(cpu) { - per_cpu(cpu_idle_state, cpu) = 1; - cpu_set(cpu, map); - } - - __get_cpu_var(cpu_idle_state) = 0; - - wmb(); - do { - ssleep(1); - for_each_online_cpu(cpu) { - if (cpu_isset(cpu, map) && !per_cpu(cpu_idle_state, cpu)) - cpu_clear(cpu, map); - } - cpus_and(map, map, cpu_online_map); - /* - * We waited 1 sec, if a CPU still did not call idle - * it may be because it is in idle and not waking up - * because it has nothing to do. - * Give all the remaining CPUS a kick. - */ - smp_call_function_mask(map, do_nothing, 0, 0); - } while (!cpus_empty(map)); - - set_cpus_allowed(current, tmp); -} -EXPORT_SYMBOL_GPL(cpu_idle_wait); - -/* - * This uses new MONITOR/MWAIT instructions on P4 processors with PNI, - * which can obviate IPI to trigger checking of need_resched. - * We execute MONITOR against need_resched and enter optimized wait state - * through MWAIT. Whenever someone changes need_resched, we would be woken - * up from MWAIT (without an IPI). - * - * New with Core Duo processors, MWAIT can take some hints based on CPU - * capability. - */ -void mwait_idle_with_hints(unsigned long ax, unsigned long cx) -{ - if (!need_resched()) { - __monitor((void *)¤t_thread_info()->flags, 0, 0); - smp_mb(); - if (!need_resched()) - __mwait(ax, cx); - } -} - -/* Default MONITOR/MWAIT with no hints, used for default C1 state */ -static void mwait_idle(void) -{ - local_irq_enable(); - mwait_idle_with_hints(0, 0); -} - -void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) -{ - if (cpu_has(c, X86_FEATURE_MWAIT)) { - printk("monitor/mwait feature present.\n"); - /* - * Skip, if setup has overridden idle. - * One CPU supports mwait => All CPUs supports mwait - */ - if (!pm_idle) { - printk("using mwait in idle threads.\n"); - pm_idle = mwait_idle; - } - } -} - -static int __init idle_setup(char *str) -{ - if (!strcmp(str, "poll")) { - printk("using polling idle threads.\n"); - pm_idle = poll_idle; -#ifdef CONFIG_X86_SMP - if (smp_num_siblings > 1) - printk("WARNING: polling idle and HT enabled, performance may degrade.\n"); -#endif - } else if (!strcmp(str, "mwait")) - force_mwait = 1; - else - return -1; - - boot_option_idle_override = 1; - return 0; -} -early_param("idle", idle_setup); - -void __show_registers(struct pt_regs *regs, int all) +void __show_regs(struct pt_regs *regs, int all) { unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L; unsigned long d0, d1, d2, d3, d6, d7; unsigned long sp; unsigned short ss, gs; + const char *board; if (user_mode_vm(regs)) { sp = regs->sp; ss = regs->ss & 0xffff; - savesegment(gs, gs); + gs = get_user_gs(regs); } else { sp = (unsigned long) (®s->sp); savesegment(ss, ss); @@ -334,14 +146,18 @@ void __show_registers(struct pt_regs *regs, int all) } printk("\n"); - printk("Pid: %d, comm: %s %s (%s %.*s)\n", + + board = dmi_get_system_info(DMI_PRODUCT_NAME); + if (!board) + board = ""; + printk("Pid: %d, comm: %s %s (%s %.*s) %s\n", task_pid_nr(current), current->comm, print_tainted(), init_utsname()->release, (int)strcspn(init_utsname()->version, " "), - init_utsname()->version); + init_utsname()->version, board); printk("EIP: %04x:[<%08lx>] EFLAGS: %08lx CPU: %d\n", - 0xffff & regs->cs, regs->ip, regs->flags, + (u16)regs->cs, regs->ip, regs->flags, smp_processor_id()); print_symbol("EIP is at %s\n", regs->ip); @@ -350,8 +166,7 @@ void __show_registers(struct pt_regs *regs, int all) printk("ESI: %08lx EDI: %08lx EBP: %08lx ESP: %08lx\n", regs->si, regs->di, regs->bp, sp); printk(" DS: %04x ES: %04x FS: %04x GS: %04x SS: %04x\n", - regs->ds & 0xffff, regs->es & 0xffff, - regs->fs & 0xffff, gs, ss); + (u16)regs->ds, (u16)regs->es, (u16)regs->fs, gs, ss); if (!all) return; @@ -378,8 +193,8 @@ void __show_registers(struct pt_regs *regs, int all) void show_regs(struct pt_regs *regs) { - __show_registers(regs, 1); - show_trace(NULL, regs, ®s->sp); + __show_regs(regs, 1); + show_trace(NULL, regs, ®s->sp, regs->bp); } /* @@ -392,7 +207,7 @@ extern void kernel_thread_helper(void); /* * Create a kernel thread */ -int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) +int kernel_thread(int (*fn)(void *), void *arg, unsigned long flags) { struct pt_regs regs; @@ -404,6 +219,7 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) regs.ds = __USER_DS; regs.es = __USER_DS; regs.fs = __KERNEL_PERCPU; + regs.gs = __KERNEL_STACK_CANARY; regs.orig_ax = -1; regs.ip = (unsigned long) kernel_thread_helper; regs.cs = __KERNEL_CS | get_kernel_rpl(); @@ -414,52 +230,6 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) } EXPORT_SYMBOL(kernel_thread); -/* - * Free current thread data structures etc.. - */ -void exit_thread(void) -{ - /* The process may have allocated an io port bitmap... nuke it. */ - if (unlikely(test_thread_flag(TIF_IO_BITMAP))) { - struct task_struct *tsk = current; - struct thread_struct *t = &tsk->thread; - int cpu = get_cpu(); - struct tss_struct *tss = &per_cpu(init_tss, cpu); - - kfree(t->io_bitmap_ptr); - t->io_bitmap_ptr = NULL; - clear_thread_flag(TIF_IO_BITMAP); - /* - * Careful, clear this in the TSS too: - */ - memset(tss->io_bitmap, 0xff, tss->io_bitmap_max); - t->io_bitmap_max = 0; - tss->io_bitmap_owner = NULL; - tss->io_bitmap_max = 0; - tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET; - put_cpu(); - } -} - -void flush_thread(void) -{ - struct task_struct *tsk = current; - - tsk->thread.debugreg0 = 0; - tsk->thread.debugreg1 = 0; - tsk->thread.debugreg2 = 0; - tsk->thread.debugreg3 = 0; - tsk->thread.debugreg6 = 0; - tsk->thread.debugreg7 = 0; - memset(tsk->thread.tls_array, 0, sizeof(tsk->thread.tls_array)); - clear_tsk_thread_flag(tsk, TIF_DEBUG); - /* - * Forget coprocessor state.. - */ - clear_fpu(tsk); - clear_used_math(); -} - void release_thread(struct task_struct *dead_task) { BUG_ON(dead_task->mm); @@ -477,9 +247,9 @@ void prepare_to_copy(struct task_struct *tsk) int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, unsigned long unused, - struct task_struct * p, struct pt_regs * regs) + struct task_struct *p, struct pt_regs *regs) { - struct pt_regs * childregs; + struct pt_regs *childregs; struct task_struct *tsk; int err; @@ -493,7 +263,7 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, p->thread.ip = (unsigned long) ret_from_fork; - savesegment(gs, p->thread.gs); + task_user_gs(p) = get_user_gs(regs); tsk = current; if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) { @@ -519,175 +289,34 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long sp, kfree(p->thread.io_bitmap_ptr); p->thread.io_bitmap_max = 0; } - return err; -} - -/* - * fill in the user structure for a core dump.. - */ -void dump_thread(struct pt_regs * regs, struct user * dump) -{ - u16 gs; - -/* changed the size calculations - should hopefully work better. lbt */ - dump->magic = CMAGIC; - dump->start_code = 0; - dump->start_stack = regs->sp & ~(PAGE_SIZE - 1); - dump->u_tsize = ((unsigned long) current->mm->end_code) >> PAGE_SHIFT; - dump->u_dsize = ((unsigned long) (current->mm->brk + (PAGE_SIZE-1))) >> PAGE_SHIFT; - dump->u_dsize -= dump->u_tsize; - dump->u_ssize = 0; - dump->u_debugreg[0] = current->thread.debugreg0; - dump->u_debugreg[1] = current->thread.debugreg1; - dump->u_debugreg[2] = current->thread.debugreg2; - dump->u_debugreg[3] = current->thread.debugreg3; - dump->u_debugreg[4] = 0; - dump->u_debugreg[5] = 0; - dump->u_debugreg[6] = current->thread.debugreg6; - dump->u_debugreg[7] = current->thread.debugreg7; - - if (dump->start_stack < TASK_SIZE) - dump->u_ssize = ((unsigned long) (TASK_SIZE - dump->start_stack)) >> PAGE_SHIFT; - - dump->regs.bx = regs->bx; - dump->regs.cx = regs->cx; - dump->regs.dx = regs->dx; - dump->regs.si = regs->si; - dump->regs.di = regs->di; - dump->regs.bp = regs->bp; - dump->regs.ax = regs->ax; - dump->regs.ds = (u16)regs->ds; - dump->regs.es = (u16)regs->es; - dump->regs.fs = (u16)regs->fs; - savesegment(gs,gs); - dump->regs.orig_ax = regs->orig_ax; - dump->regs.ip = regs->ip; - dump->regs.cs = (u16)regs->cs; - dump->regs.flags = regs->flags; - dump->regs.sp = regs->sp; - dump->regs.ss = (u16)regs->ss; - - dump->u_fpvalid = dump_fpu (regs, &dump->i387); -} -EXPORT_SYMBOL(dump_thread); - -/* - * Capture the user space registers if the task is not running (in user space) - */ -int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) -{ - struct pt_regs ptregs = *task_pt_regs(tsk); - ptregs.cs &= 0xffff; - ptregs.ds &= 0xffff; - ptregs.es &= 0xffff; - ptregs.ss &= 0xffff; - elf_core_copy_regs(regs, &ptregs); + ds_copy_thread(p, current); - return 1; -} + clear_tsk_thread_flag(p, TIF_DEBUGCTLMSR); + p->thread.debugctlmsr = 0; -#ifdef CONFIG_SECCOMP -void hard_disable_TSC(void) -{ - write_cr4(read_cr4() | X86_CR4_TSD); -} -void disable_TSC(void) -{ - preempt_disable(); - if (!test_and_set_thread_flag(TIF_NOTSC)) - /* - * Must flip the CPU state synchronously with - * TIF_NOTSC in the current running context. - */ - hard_disable_TSC(); - preempt_enable(); -} -void hard_enable_TSC(void) -{ - write_cr4(read_cr4() & ~X86_CR4_TSD); + return err; } -#endif /* CONFIG_SECCOMP */ -static noinline void -__switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, - struct tss_struct *tss) +void +start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) { - struct thread_struct *prev, *next; - unsigned long debugctl; - - prev = &prev_p->thread; - next = &next_p->thread; - - debugctl = prev->debugctlmsr; - if (next->ds_area_msr != prev->ds_area_msr) { - /* we clear debugctl to make sure DS - * is not in use when we change it */ - debugctl = 0; - wrmsrl(MSR_IA32_DEBUGCTLMSR, 0); - wrmsr(MSR_IA32_DS_AREA, next->ds_area_msr, 0); - } - - if (next->debugctlmsr != debugctl) - wrmsr(MSR_IA32_DEBUGCTLMSR, next->debugctlmsr, 0); - - if (test_tsk_thread_flag(next_p, TIF_DEBUG)) { - set_debugreg(next->debugreg0, 0); - set_debugreg(next->debugreg1, 1); - set_debugreg(next->debugreg2, 2); - set_debugreg(next->debugreg3, 3); - /* no 4 and 5 */ - set_debugreg(next->debugreg6, 6); - set_debugreg(next->debugreg7, 7); - } - -#ifdef CONFIG_SECCOMP - if (test_tsk_thread_flag(prev_p, TIF_NOTSC) ^ - test_tsk_thread_flag(next_p, TIF_NOTSC)) { - /* prev and next are different */ - if (test_tsk_thread_flag(next_p, TIF_NOTSC)) - hard_disable_TSC(); - else - hard_enable_TSC(); - } -#endif - - if (test_tsk_thread_flag(prev_p, TIF_BTS_TRACE_TS)) - ptrace_bts_take_timestamp(prev_p, BTS_TASK_DEPARTS); - - if (test_tsk_thread_flag(next_p, TIF_BTS_TRACE_TS)) - ptrace_bts_take_timestamp(next_p, BTS_TASK_ARRIVES); - - - if (!test_tsk_thread_flag(next_p, TIF_IO_BITMAP)) { - /* - * Disable the bitmap via an invalid offset. We still cache - * the previous bitmap owner and the IO bitmap contents: - */ - tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET; - return; - } - - if (likely(next == tss->io_bitmap_owner)) { - /* - * Previous owner of the bitmap (hence the bitmap content) - * matches the next task, we dont have to do anything but - * to set a valid offset in the TSS: - */ - tss->x86_tss.io_bitmap_base = IO_BITMAP_OFFSET; - return; - } + set_user_gs(regs, 0); + regs->fs = 0; + set_fs(USER_DS); + regs->ds = __USER_DS; + regs->es = __USER_DS; + regs->ss = __USER_DS; + regs->cs = __USER_CS; + regs->ip = new_ip; + regs->sp = new_sp; /* - * Lazy TSS's I/O bitmap copy. We set an invalid offset here - * and we let the task to get a GPF in case an I/O instruction - * is performed. The handler of the GPF will verify that the - * faulting task has a valid I/O bitmap and, it true, does the - * real copy and restart the instruction. This will save us - * redundant copies when the currently switched task does not - * perform any I/O during its timeslice. + * Free the old FP and other extended state */ - tss->x86_tss.io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY; + free_thread_xstate(current); } +EXPORT_SYMBOL_GPL(start_thread); + /* * switch_to(x,yn) should switch tasks from x to y. @@ -716,7 +345,8 @@ __switch_to_xtra(struct task_struct *prev_p, struct task_struct *next_p, * the task-switch, and shows up in ret_from_fork in entry.S, * for example. */ -struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct task_struct *next_p) +__notrace_funcgraph struct task_struct * +__switch_to(struct task_struct *prev_p, struct task_struct *next_p) { struct thread_struct *prev = &prev_p->thread, *next = &next_p->thread; @@ -730,7 +360,7 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas /* we're going to use this soon, after a few expensive things */ if (next_p->fpu_counter > 5) - prefetch(&next->i387.fxsave); + prefetch(next->xstate); /* * Reload esp0. @@ -747,7 +377,7 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas * used %fs or %gs (it does not today), or if the kernel is * running inside of a hypervisor layer. */ - savesegment(gs, prev->gs); + lazy_save_gs(prev->gs); /* * Load the per-thread Thread-Local Storage descriptor. @@ -782,72 +412,55 @@ struct task_struct fastcall * __switch_to(struct task_struct *prev_p, struct tas /* If the task has used fpu the last 5 timeslices, just do a full * restore of the math state immediately to avoid the trap; the * chances of needing FPU soon are obviously high now + * + * tsk_used_math() checks prevent calling math_state_restore(), + * which can sleep in the case of !tsk_used_math() */ - if (next_p->fpu_counter > 5) + if (tsk_used_math(next_p) && next_p->fpu_counter > 5) math_state_restore(); /* * Restore %gs if needed (which is common) */ if (prev->gs | next->gs) - loadsegment(gs, next->gs); + lazy_load_gs(next->gs); - x86_write_percpu(current_task, next_p); + percpu_write(current_task, next_p); return prev_p; } -asmlinkage int sys_fork(struct pt_regs regs) -{ - return do_fork(SIGCHLD, regs.sp, ®s, 0, NULL, NULL); -} - -asmlinkage int sys_clone(struct pt_regs regs) +int sys_clone(struct pt_regs *regs) { unsigned long clone_flags; unsigned long newsp; int __user *parent_tidptr, *child_tidptr; - clone_flags = regs.bx; - newsp = regs.cx; - parent_tidptr = (int __user *)regs.dx; - child_tidptr = (int __user *)regs.di; + clone_flags = regs->bx; + newsp = regs->cx; + parent_tidptr = (int __user *)regs->dx; + child_tidptr = (int __user *)regs->di; if (!newsp) - newsp = regs.sp; - return do_fork(clone_flags, newsp, ®s, 0, parent_tidptr, child_tidptr); -} - -/* - * This is trivial, and on the face of it looks like it - * could equally well be done in user mode. - * - * Not so, for quite unobvious reasons - register pressure. - * In user mode vfork() cannot have a stack frame, and if - * done by calling the "clone()" system call directly, you - * do not have enough call-clobbered registers to hold all - * the information you need. - */ -asmlinkage int sys_vfork(struct pt_regs regs) -{ - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.sp, ®s, 0, NULL, NULL); + newsp = regs->sp; + return do_fork(clone_flags, newsp, regs, 0, parent_tidptr, child_tidptr); } /* * sys_execve() executes a new program. */ -asmlinkage int sys_execve(struct pt_regs regs) +int sys_execve(struct pt_regs *regs) { int error; - char * filename; + char *filename; - filename = getname((char __user *) regs.bx); + filename = getname((char __user *) regs->bx); error = PTR_ERR(filename); if (IS_ERR(filename)) goto out; error = do_execve(filename, - (char __user * __user *) regs.cx, - (char __user * __user *) regs.dx, - ®s); + (char __user * __user *) regs->cx, + (char __user * __user *) regs->dx, + regs); if (error == 0) { /* Make sure we don't return using sysenter.. */ set_thread_flag(TIF_IRET);