X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fx86_64%2Fkernel%2Fprocess.c;h=051ad1117ff85c291c3967dc33c14157491ddf23;hb=9464c7cf61b9433057924c36e6e02f303a00e768;hp=e80d5eb1b699cf099fd6bffee09f88dd2a5d4dbf;hpb=daddc0d38b3571bed170afa273a49a0eba090c1e;p=linux-2.6.git diff --git a/arch/x86_64/kernel/process.c b/arch/x86_64/kernel/process.c index e80d5eb1b..051ad1117 100644 --- a/arch/x86_64/kernel/process.c +++ b/arch/x86_64/kernel/process.c @@ -8,7 +8,8 @@ * * X86-64 port * Andi Kleen. - * + * + * CPU hotplug support - ashok.raj@intel.com * $Id: process.c,v 1.38 2002/01/15 10:08:03 ak Exp $ */ @@ -18,6 +19,7 @@ #include +#include #include #include #include @@ -30,9 +32,11 @@ #include #include #include -#include #include -#include +#include +#include +#include +#include #include #include @@ -47,45 +51,76 @@ #include #include #include +#include asmlinkage extern void ret_from_fork(void); unsigned long kernel_thread_flags = CLONE_VM | CLONE_UNTRACED; -atomic_t hlt_counter = ATOMIC_INIT(0); +unsigned long boot_option_idle_override = 0; +EXPORT_SYMBOL(boot_option_idle_override); /* * Powermanagement idle function, if any.. */ void (*pm_idle)(void); +static DEFINE_PER_CPU(unsigned int, cpu_idle_state); + +static ATOMIC_NOTIFIER_HEAD(idle_notifier); + +void idle_notifier_register(struct notifier_block *n) +{ + atomic_notifier_chain_register(&idle_notifier, n); +} +EXPORT_SYMBOL_GPL(idle_notifier_register); -void disable_hlt(void) +void idle_notifier_unregister(struct notifier_block *n) { - atomic_inc(&hlt_counter); + atomic_notifier_chain_unregister(&idle_notifier, n); } +EXPORT_SYMBOL(idle_notifier_unregister); -EXPORT_SYMBOL(disable_hlt); +enum idle_state { CPU_IDLE, CPU_NOT_IDLE }; +static DEFINE_PER_CPU(enum idle_state, idle_state) = CPU_NOT_IDLE; + +void enter_idle(void) +{ + __get_cpu_var(idle_state) = CPU_IDLE; + atomic_notifier_call_chain(&idle_notifier, IDLE_START, NULL); +} -void enable_hlt(void) +static void __exit_idle(void) { - atomic_dec(&hlt_counter); + __get_cpu_var(idle_state) = CPU_NOT_IDLE; + atomic_notifier_call_chain(&idle_notifier, IDLE_END, NULL); } -EXPORT_SYMBOL(enable_hlt); +/* Called from interrupts to signify idle end */ +void exit_idle(void) +{ + if (current->pid | read_pda(irqcount)) + return; + __exit_idle(); +} /* * We use this if we don't have any better * idle routine.. */ -void default_idle(void) +static void default_idle(void) { - if (!atomic_read(&hlt_counter)) { + local_irq_enable(); + + clear_thread_flag(TIF_POLLING_NRFLAG); + smp_mb__after_clear_bit(); + while (!need_resched()) { local_irq_disable(); if (!need_resched()) safe_halt(); else local_irq_enable(); } + set_thread_flag(TIF_POLLING_NRFLAG); } /* @@ -95,30 +130,70 @@ void default_idle(void) */ static void poll_idle (void) { - int oldval; - local_irq_enable(); - /* - * Deal with another CPU just having chosen a thread to - * run here: - */ - oldval = test_and_clear_thread_flag(TIF_NEED_RESCHED); - - if (!oldval) { - set_thread_flag(TIF_POLLING_NRFLAG); - asm volatile( - "2:" - "testl %0,%1;" - "rep; nop;" - "je 2b;" - : : - "i" (_TIF_NEED_RESCHED), - "m" (current_thread_info()->flags)); - } else { - set_need_resched(); + asm volatile( + "2:" + "testl %0,%1;" + "rep; nop;" + "je 2b;" + : : + "i" (_TIF_NEED_RESCHED), + "m" (current_thread_info()->flags)); +} + +void cpu_idle_wait(void) +{ + unsigned int cpu, this_cpu = get_cpu(); + cpumask_t map; + + 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); + } while (!cpus_empty(map)); +} +EXPORT_SYMBOL_GPL(cpu_idle_wait); + +#ifdef CONFIG_HOTPLUG_CPU +DECLARE_PER_CPU(int, cpu_state); + +#include +/* We halt the CPU with physical CPU hotplug */ +static inline void play_dead(void) +{ + idle_task_exit(); + wbinvd(); + mb(); + /* Ack it */ + __get_cpu_var(cpu_state) = CPU_DEAD; + + local_irq_disable(); + while (1) + halt(); +} +#else +static inline void play_dead(void) +{ + BUG(); } +#endif /* CONFIG_HOTPLUG_CPU */ /* * The idle thread. There's no useful work to be @@ -128,14 +203,30 @@ static void poll_idle (void) */ void cpu_idle (void) { + set_thread_flag(TIF_POLLING_NRFLAG); + /* endless idle loop with no priority at all */ while (1) { - void (*idle)(void) = pm_idle; - if (!idle) - idle = default_idle; - while (!need_resched()) + while (!need_resched()) { + void (*idle)(void); + + if (__get_cpu_var(cpu_idle_state)) + __get_cpu_var(cpu_idle_state) = 0; + + rmb(); + idle = pm_idle; + if (!idle) + idle = default_idle; + if (cpu_is_offline(smp_processor_id())) + play_dead(); + enter_idle(); idle(); + __exit_idle(); + } + + preempt_enable_no_resched(); schedule(); + preempt_disable(); } } @@ -150,27 +241,22 @@ static void mwait_idle(void) { local_irq_enable(); - if (!need_resched()) { - set_thread_flag(TIF_POLLING_NRFLAG); - do { - __monitor((void *)¤t_thread_info()->flags, 0, 0); - if (need_resched()) - break; - __mwait(0, 0); - } while (!need_resched()); - clear_thread_flag(TIF_POLLING_NRFLAG); + while (!need_resched()) { + __monitor((void *)¤t_thread_info()->flags, 0, 0); + smp_mb(); + if (need_resched()) + break; + __mwait(0, 0); } } -void __init select_idle_routine(const struct cpuinfo_x86 *c) +void __cpuinit select_idle_routine(const struct cpuinfo_x86 *c) { static int printed; if (cpu_has(c, X86_FEATURE_MWAIT)) { /* * Skip, if setup has overridden idle. - * Also, take care of system with asymmetric CPUs. - * Use, mwait_idle only if all cpus support it. - * If not, we fallback to default_idle() + * One CPU supports mwait => All CPUs supports mwait */ if (!pm_idle) { if (!printed) { @@ -179,10 +265,7 @@ void __init select_idle_routine(const struct cpuinfo_x86 *c) } pm_idle = mwait_idle; } - return; } - pm_idle = default_idle; - return; } static int __init idle_setup (char *str) @@ -192,6 +275,7 @@ static int __init idle_setup (char *str) pm_idle = poll_idle; } + boot_option_idle_override = 1; return 1; } @@ -206,11 +290,15 @@ void __show_regs(struct pt_regs * regs) printk("\n"); print_modules(); - printk("Pid: %d, comm: %.20s %s %s\n", - current->pid, current->comm, print_tainted(), UTS_RELEASE); + printk("Pid: %d, comm: %.20s %s %s %.*s\n", + current->pid, current->comm, print_tainted(), + system_utsname.release, + (int)strcspn(system_utsname.version, " "), + system_utsname.version); printk("RIP: %04lx:[<%016lx>] ", regs->cs & 0xffff, regs->rip); printk_address(regs->rip); - printk("\nRSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp, regs->eflags); + printk("\nRSP: %04lx:%016lx EFLAGS: %08lx\n", regs->ss, regs->rsp, + regs->eflags); printk("RAX: %016lx RBX: %016lx RCX: %016lx\n", regs->rax, regs->rbx, regs->rcx); printk("RDX: %016lx RSI: %016lx RDI: %016lx\n", @@ -245,6 +333,7 @@ void __show_regs(struct pt_regs * regs) void show_regs(struct pt_regs *regs) { + printk("CPU %d:", smp_processor_id()); __show_regs(regs); show_trace(®s->rsp); } @@ -255,11 +344,18 @@ void show_regs(struct pt_regs *regs) void exit_thread(void) { struct task_struct *me = current; + struct thread_struct *t = &me->thread; + if (me->thread.io_bitmap_ptr) { - struct tss_struct *tss = init_tss + get_cpu(); - kfree(me->thread.io_bitmap_ptr); - me->thread.io_bitmap_ptr = NULL; - tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET; + struct tss_struct *tss = &per_cpu(init_tss, get_cpu()); + + kfree(t->io_bitmap_ptr); + t->io_bitmap_ptr = NULL; + /* + * Careful, clear this in the TSS too: + */ + memset(tss->io_bitmap, 0xff, t->io_bitmap_max); + t->io_bitmap_max = 0; put_cpu(); } } @@ -283,7 +379,7 @@ void flush_thread(void) * Forget coprocessor state.. */ clear_fpu(tsk); - tsk->used_math = 0; + clear_used_math(); } void release_thread(struct task_struct *dead_task) @@ -340,36 +436,37 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp, struct pt_regs * childregs; struct task_struct *me = current; - childregs = ((struct pt_regs *) (THREAD_SIZE + (unsigned long) p->thread_info)) - 1; - + childregs = ((struct pt_regs *) + (THREAD_SIZE + task_stack_page(p))) - 1; *childregs = *regs; childregs->rax = 0; childregs->rsp = rsp; - if (rsp == ~0UL) { + if (rsp == ~0UL) childregs->rsp = (unsigned long)childregs; - } - p->set_child_tid = p->clear_child_tid = NULL; p->thread.rsp = (unsigned long) childregs; p->thread.rsp0 = (unsigned long) (childregs+1); p->thread.userrsp = me->thread.userrsp; - set_ti_thread_flag(p->thread_info, TIF_FORK); + set_tsk_thread_flag(p, TIF_FORK); p->thread.fs = me->thread.fs; p->thread.gs = me->thread.gs; - asm("movl %%gs,%0" : "=m" (p->thread.gsindex)); - asm("movl %%fs,%0" : "=m" (p->thread.fsindex)); - asm("movl %%es,%0" : "=m" (p->thread.es)); - asm("movl %%ds,%0" : "=m" (p->thread.ds)); + asm("mov %%gs,%0" : "=m" (p->thread.gsindex)); + asm("mov %%fs,%0" : "=m" (p->thread.fsindex)); + asm("mov %%es,%0" : "=m" (p->thread.es)); + asm("mov %%ds,%0" : "=m" (p->thread.ds)); if (unlikely(me->thread.io_bitmap_ptr != NULL)) { p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL); - if (!p->thread.io_bitmap_ptr) + if (!p->thread.io_bitmap_ptr) { + p->thread.io_bitmap_max = 0; return -ENOMEM; - memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, IO_BITMAP_BYTES); + } + memcpy(p->thread.io_bitmap_ptr, me->thread.io_bitmap_ptr, + IO_BITMAP_BYTES); } /* @@ -387,15 +484,17 @@ int copy_thread(int nr, unsigned long clone_flags, unsigned long rsp, } err = 0; out: - if (err && p->thread.io_bitmap_ptr) + if (err && p->thread.io_bitmap_ptr) { kfree(p->thread.io_bitmap_ptr); + p->thread.io_bitmap_max = 0; + } return err; } /* * This special macro can be used to load a debugging register */ -#define loaddebug(thread,r) set_debug(thread->debugreg ## r, r) +#define loaddebug(thread,r) set_debugreg(thread->debugreg ## r, r) /* * switch_to(x,y) should switch tasks from x to y. @@ -403,15 +502,16 @@ out: * This could still be optimized: * - fold all the options into a flag word and test it with a single test. * - could test fs/gs bitsliced + * + * Kprobes not supported here. Set the probe on schedule instead. */ -struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct *next_p) +__kprobes 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; int cpu = smp_processor_id(); - struct tss_struct *tss = init_tss + cpu; - - unlazy_fpu(prev_p); + struct tss_struct *tss = &per_cpu(init_tss, cpu); /* * Reload esp0, LDT and the page table pointer: @@ -422,11 +522,11 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * * Switch DS and ES. * This won't pick up thread selector changes, but I guess that is ok. */ - asm volatile("movl %%es,%0" : "=m" (prev->es)); + asm volatile("mov %%es,%0" : "=m" (prev->es)); if (unlikely(next->es | prev->es)) loadsegment(es, next->es); - asm volatile ("movl %%ds,%0" : "=m" (prev->ds)); + asm volatile ("mov %%ds,%0" : "=m" (prev->ds)); if (unlikely(next->ds | prev->ds)) loadsegment(ds, next->ds); @@ -437,7 +537,7 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * */ { unsigned fsindex; - asm volatile("movl %%fs,%0" : "=g" (fsindex)); + asm volatile("movl %%fs,%0" : "=r" (fsindex)); /* segment register != 0 always requires a reload. also reload when it has changed. when prev process used 64bit base always reload @@ -458,7 +558,7 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * } { unsigned gsindex; - asm volatile("movl %%gs,%0" : "=g" (gsindex)); + asm volatile("movl %%gs,%0" : "=r" (gsindex)); if (unlikely(gsindex | next->gsindex | prev->gs)) { load_gs_index(next->gsindex); if (gsindex) @@ -470,12 +570,18 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * } /* - * Switch the PDA context. + * Switch the PDA and FPU contexts. */ prev->userrsp = read_pda(oldrsp); write_pda(oldrsp, next->userrsp); write_pda(pcurrent, next_p); - write_pda(kernelstack, (unsigned long)next_p->thread_info + THREAD_SIZE - PDA_STACKOFFSET); + + /* This must be here to ensure both math_state_restore() and + kernel_fpu_begin() work consistently. + And the AMD workaround requires it to be after DS reload. */ + unlazy_fpu(prev_p); + write_pda(kernelstack, + task_stack_page(next_p) + THREAD_SIZE - PDA_STACKOFFSET); /* * Now maybe reload the debug registers @@ -495,22 +601,18 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * * Handle the IO bitmap */ if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr)) { - if (next->io_bitmap_ptr) { + if (next->io_bitmap_ptr) /* - * 2 cachelines copy ... not good, but not that - * bad either. Anyone got something better? - * This only affects processes which use ioperm(). - */ - memcpy(tss->io_bitmap, next->io_bitmap_ptr, IO_BITMAP_BYTES); - tss->io_bitmap_base = IO_BITMAP_OFFSET; - } else { + * Copy the relevant range of the IO bitmap. + * Normally this is 128 bytes or less: + */ + memcpy(tss->io_bitmap, next->io_bitmap_ptr, + max(prev->io_bitmap_max, next->io_bitmap_max)); + else { /* - * a bitmap offset pointing outside of the TSS limit - * causes a nicely controllable SIGSEGV if a process - * tries to use a port IO instruction. The first - * sys_ioperm() call sets up the bitmap properly. + * Clear any possible leftover bits: */ - tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET; + memset(tss->io_bitmap, 0xff, prev->io_bitmap_max); } } @@ -521,7 +623,8 @@ struct task_struct *__switch_to(struct task_struct *prev_p, struct task_struct * * sys_execve() executes a new program. */ asmlinkage -long sys_execve(char *name, char **argv,char **envp, struct pt_regs regs) +long sys_execve(char __user *name, char __user * __user *argv, + char __user * __user *envp, struct pt_regs regs) { long error; char * filename; @@ -531,8 +634,11 @@ long sys_execve(char *name, char **argv,char **envp, struct pt_regs regs) if (IS_ERR(filename)) return error; error = do_execve(filename, argv, envp, ®s); - if (error == 0) + if (error == 0) { + task_lock(current); current->ptrace &= ~PT_DTRACE; + task_unlock(current); + } putname(filename); return error; } @@ -545,17 +651,18 @@ void set_personality_64bit(void) clear_thread_flag(TIF_IA32); } -asmlinkage long sys_fork(struct pt_regs regs) +asmlinkage long sys_fork(struct pt_regs *regs) { - return do_fork(SIGCHLD, regs.rsp, ®s, 0, NULL, NULL); + return do_fork(SIGCHLD, regs->rsp, regs, 0, NULL, NULL); } -asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp, void *parent_tid, void *child_tid, struct pt_regs regs) +asmlinkage long +sys_clone(unsigned long clone_flags, unsigned long newsp, + void __user *parent_tid, void __user *child_tid, struct pt_regs *regs) { if (!newsp) - newsp = regs.rsp; - return do_fork(clone_flags & ~CLONE_IDLETASK, newsp, ®s, 0, - parent_tid, child_tid); + newsp = regs->rsp; + return do_fork(clone_flags, newsp, regs, 0, parent_tid, child_tid); } /* @@ -568,18 +675,12 @@ asmlinkage long sys_clone(unsigned long clone_flags, unsigned long newsp, void * * do not have enough call-clobbered registers to hold all * the information you need. */ -asmlinkage long sys_vfork(struct pt_regs regs) +asmlinkage long sys_vfork(struct pt_regs *regs) { - return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs.rsp, ®s, 0, + return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->rsp, regs, 0, NULL, NULL); } -/* - * These bracket the sleeping functions.. - */ -#define first_sched ((unsigned long) scheduling_functions_start_here) -#define last_sched ((unsigned long) scheduling_functions_end_here) - unsigned long get_wchan(struct task_struct *p) { unsigned long stack; @@ -588,22 +689,21 @@ unsigned long get_wchan(struct task_struct *p) if (!p || p == current || p->state==TASK_RUNNING) return 0; - stack = (unsigned long)p->thread_info; + stack = (unsigned long)task_stack_page(p); if (p->thread.rsp < stack || p->thread.rsp > stack+THREAD_SIZE) return 0; fp = *(u64 *)(p->thread.rsp); do { - if (fp < (unsigned long)stack || fp > (unsigned long)stack+THREAD_SIZE) + if (fp < (unsigned long)stack || + fp > (unsigned long)stack+THREAD_SIZE) return 0; rip = *(u64 *)(fp+8); - if (rip < first_sched || rip >= last_sched) + if (!in_sched_functions(rip)) return rip; fp = *(u64 *)fp; } while (count++ < 16); return 0; } -#undef last_sched -#undef first_sched long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) { @@ -613,7 +713,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) switch (code) { case ARCH_SET_GS: - if (addr >= TASK_SIZE) + if (addr >= TASK_SIZE_OF(task)) return -EPERM; cpu = get_cpu(); /* handle small bases via the GDT because that's faster to @@ -630,8 +730,8 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) task->thread.gsindex = 0; task->thread.gs = addr; if (doit) { - load_gs_index(0); - ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr); + load_gs_index(0); + ret = checking_wrmsrl(MSR_KERNEL_GS_BASE, addr); } } put_cpu(); @@ -639,7 +739,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) case ARCH_SET_FS: /* Not strictly needed for fs, but do it for symmetry with gs */ - if (addr >= TASK_SIZE) + if (addr >= TASK_SIZE_OF(task)) return -EPERM; cpu = get_cpu(); /* handle small bases via the GDT because that's faster to @@ -648,7 +748,7 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) set_32bit_tls(task, FS_TLS, addr); if (doit) { load_TLS(&task->thread, cpu); - asm volatile("movl %0,%%fs" :: "r" (FS_TLS_SEL)); + asm volatile("movl %0,%%fs" :: "r"(FS_TLS_SEL)); } task->thread.fsindex = FS_TLS_SEL; task->thread.fs = 0; @@ -658,8 +758,8 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) if (doit) { /* set the selector to 0 to not confuse __switch_to */ - asm volatile("movl %0,%%fs" :: "r" (0)); - ret = checking_wrmsrl(MSR_FS_BASE, addr); + asm volatile("movl %0,%%fs" :: "r" (0)); + ret = checking_wrmsrl(MSR_FS_BASE, addr); } } put_cpu(); @@ -668,22 +768,28 @@ long do_arch_prctl(struct task_struct *task, int code, unsigned long addr) unsigned long base; if (task->thread.fsindex == FS_TLS_SEL) base = read_32bit_tls(task, FS_TLS); - else if (doit) { + else if (doit) rdmsrl(MSR_FS_BASE, base); - } else + else base = task->thread.fs; - ret = put_user(base, (unsigned long *)addr); + ret = put_user(base, (unsigned long __user *)addr); break; } case ARCH_GET_GS: { unsigned long base; + unsigned gsindex; if (task->thread.gsindex == GS_TLS_SEL) base = read_32bit_tls(task, GS_TLS); else if (doit) { - rdmsrl(MSR_KERNEL_GS_BASE, base); - } else + asm("movl %%gs,%0" : "=r" (gsindex)); + if (gsindex) + rdmsrl(MSR_KERNEL_GS_BASE, base); + else + base = task->thread.gs; + } + else base = task->thread.gs; - ret = put_user(base, (unsigned long *)addr); + ret = put_user(base, (unsigned long __user *)addr); break; } @@ -707,8 +813,7 @@ int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) { struct pt_regs *pp, ptregs; - pp = (struct pt_regs *)(tsk->thread.rsp0); - --pp; + pp = task_pt_regs(tsk); ptregs = *pp; ptregs.cs &= 0xffff; @@ -718,3 +823,10 @@ int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) return 1; } + +unsigned long arch_align_stack(unsigned long sp) +{ + if (randomize_va_space) + sp -= get_random_int() % 8192; + return sp & ~0xf; +}