#include <linux/kallsyms.h>
#include <linux/ptrace.h>
#include <linux/random.h>
+#include <linux/personality.h>
#include <asm/uaccess.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <asm/cpu.h>
+#include <asm/pda.h>
asmlinkage void ret_from_fork(void) __asm__("ret_from_fork");
/* XXX XEN doesn't use default_idle(), poll_idle(). Use xen_idle() instead. */
void xen_idle(void)
{
- local_irq_disable();
+ current_thread_info()->status &= ~TS_POLLING;
+ /*
+ * TS_POLLING-cleared state must be visible before we
+ * test NEED_RESCHED:
+ */
+ smp_mb();
- if (need_resched())
+ local_irq_disable();
+ if (!need_resched())
+ safe_halt(); /* enables interrupts racelessly */
+ else
local_irq_enable();
- else {
- current_thread_info()->status &= ~TS_POLLING;
- smp_mb__after_clear_bit();
- safe_halt();
- current_thread_info()->status |= TS_POLLING;
- }
+ current_thread_info()->status |= TS_POLLING;
}
#ifdef CONFIG_APM_MODULE
EXPORT_SYMBOL(default_idle);
current_thread_info()->status |= TS_POLLING;
-
/* endless idle loop with no priority at all */
while (1) {
while (!need_resched()) {
void cpu_idle_wait(void)
{
unsigned int cpu, this_cpu = get_cpu();
- cpumask_t map;
+ cpumask_t map, tmp = current->cpus_allowed;
set_cpus_allowed(current, cpumask_of_cpu(this_cpu));
put_cpu();
}
cpus_and(map, map, cpu_online_map);
} while (!cpus_empty(map));
+
+ set_cpus_allowed(current, tmp);
}
EXPORT_SYMBOL_GPL(cpu_idle_wait);
/* XXX XEN doesn't use mwait_idle(), select_idle_routine(), idle_setup(). */
/* Always use xen_idle() instead. */
+void mwait_idle_with_hints(unsigned long eax, unsigned long ecx) {}
+
void __devinit select_idle_routine(const struct cpuinfo_x86 *c) {}
void show_regs(struct pt_regs * regs)
unsigned long cr0 = 0L, cr2 = 0L, cr3 = 0L, cr4 = 0L;
printk("\n");
- printk("Pid: %d, comm: %20s\n", current->pid, current->comm);
- printk("EIP: %04x:[<%08lx>] CPU: %d\n",0xffff & regs->xcs,regs->eip, smp_processor_id());
+ printk("Pid: %d[#%u], comm: %20s\n",
+ current->pid, current->xid, current->comm);
+ printk("EIP: %04x:[<%08lx>] CPU: %d\n",
+ 0xffff & regs->xcs,regs->eip, smp_processor_id());
print_symbol("EIP is at %s\n", regs->eip);
if (user_mode_vm(regs))
printk(" ESP: %04x:%08lx",0xffff & regs->xss,regs->esp);
printk(" EFLAGS: %08lx %s (%s %.*s)\n",
- regs->eflags, print_tainted(), system_utsname.release,
- (int)strcspn(system_utsname.version, " "),
- system_utsname.version);
+ regs->eflags, print_tainted(), init_utsname()->release,
+ (int)strcspn(init_utsname()->version, " "),
+ init_utsname()->version);
printk("EAX: %08lx EBX: %08lx ECX: %08lx EDX: %08lx\n",
regs->eax,regs->ebx,regs->ecx,regs->edx);
printk("ESI: %08lx EDI: %08lx EBP: %08lx",
regs->esi, regs->edi, regs->ebp);
- printk(" DS: %04x ES: %04x\n",
- 0xffff & regs->xds,0xffff & regs->xes);
+ printk(" DS: %04x ES: %04x GS: %04x\n",
+ 0xffff & regs->xds,0xffff & regs->xes, 0xffff & regs->xgs);
cr0 = read_cr0();
cr2 = read_cr2();
* the "args".
*/
extern void kernel_thread_helper(void);
-__asm__(".section .text\n"
- ".align 4\n"
- "kernel_thread_helper:\n\t"
- "movl %edx,%eax\n\t"
- "pushl %edx\n\t"
- "call *%ebx\n\t"
- "pushl %eax\n\t"
- "call do_exit\n"
- ".previous");
/*
* Create a kernel thread
regs.xds = __USER_DS;
regs.xes = __USER_DS;
+ regs.xgs = __KERNEL_PDA;
regs.orig_eax = -1;
regs.eip = (unsigned long) kernel_thread_helper;
- regs.xcs = GET_KERNEL_CS();
+ regs.xcs = __KERNEL_CS | get_kernel_rpl();
regs.eflags = X86_EFLAGS_IF | X86_EFLAGS_SF | X86_EFLAGS_PF | 0x2;
/* 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);
}
EXPORT_SYMBOL(kernel_thread);
p->thread.eip = (unsigned long) ret_from_fork;
savesegment(fs,p->thread.fs);
- savesegment(gs,p->thread.gs);
tsk = current;
if (unlikely(test_tsk_thread_flag(tsk, TIF_IO_BITMAP))) {
- p->thread.io_bitmap_ptr = kmalloc(IO_BITMAP_BYTES, GFP_KERNEL);
+ p->thread.io_bitmap_ptr = kmemdup(tsk->thread.io_bitmap_ptr,
+ IO_BITMAP_BYTES, GFP_KERNEL);
if (!p->thread.io_bitmap_ptr) {
p->thread.io_bitmap_max = 0;
return -ENOMEM;
}
- memcpy(p->thread.io_bitmap_ptr, tsk->thread.io_bitmap_ptr,
- IO_BITMAP_BYTES);
set_tsk_thread_flag(p, TIF_IO_BITMAP);
}
dump->regs.ds = regs->xds;
dump->regs.es = regs->xes;
savesegment(fs,dump->regs.fs);
- savesegment(gs,dump->regs.gs);
+ dump->regs.gs = regs->xgs;
dump->regs.orig_eax = regs->orig_eax;
dump->regs.eip = regs->eip;
dump->regs.cs = regs->xcs;
return 1;
}
+static noinline void __switch_to_xtra(struct task_struct *next_p)
+{
+ struct thread_struct *next;
+
+ next = &next_p->thread;
+
+ if (test_tsk_thread_flag(next_p, TIF_DEBUG)) {
+ set_debugreg(next->debugreg[0], 0);
+ set_debugreg(next->debugreg[1], 1);
+ set_debugreg(next->debugreg[2], 2);
+ set_debugreg(next->debugreg[3], 3);
+ /* no 4 and 5 */
+ set_debugreg(next->debugreg[6], 6);
+ set_debugreg(next->debugreg[7], 7);
+ }
+#ifndef CONFIG_XEN
+ 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->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->io_bitmap_base = IO_BITMAP_OFFSET;
+ return;
+ }
+ /*
+ * 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.
+ */
+ tss->io_bitmap_base = INVALID_IO_BITMAP_OFFSET_LAZY;
+#endif /* !CONFIG_XEN */
+}
+
/*
* This function selects if the context switch from prev to next
* has to tweak the TSC disable bit in the cr4.
#ifndef CONFIG_X86_NO_TSS
struct tss_struct *tss = &per_cpu(init_tss, cpu);
#endif
- struct physdev_set_iopl iopl_op;
struct physdev_set_iobitmap iobmp_op;
multicall_entry_t _mcl[8], *mcl = _mcl;
C(0); C(1); C(2);
#undef C
- if (unlikely(prev->iopl != next->iopl)) {
- iopl_op.iopl = (next->iopl == 0) ? 1 : (next->iopl >> 12) & 3;
- mcl->op = __HYPERVISOR_physdev_op;
- mcl->args[0] = PHYSDEVOP_set_iopl;
- mcl->args[1] = (unsigned long)&iopl_op;
- mcl++;
- }
-
if (unlikely(prev->io_bitmap_ptr || next->io_bitmap_ptr)) {
iobmp_op.bitmap = (char *)next->io_bitmap_ptr;
iobmp_op.nr_ports = next->io_bitmap_ptr ? IO_BITMAP_BITS : 0;
(void)HYPERVISOR_multicall(_mcl, mcl - _mcl);
/*
- * Restore %fs and %gs if needed.
+ * Restore %fs if needed.
*
- * Glibc normally makes %fs be zero, and %gs is one of
- * the TLS segments.
+ * Glibc normally makes %fs be zero.
*/
if (unlikely(next->fs))
loadsegment(fs, next->fs);
- if (next->gs)
- loadsegment(gs, next->gs);
+ write_pda(pcurrent, next_p);
+
+ /* we're going to use this soon, after a few expensive things */
+ if (next_p->fpu_counter > 5)
+ prefetch(&next->i387.fxsave);
/*
- * Now maybe reload the debug registers
+ * Now maybe handle debug registers and/or IO bitmaps
*/
- if (unlikely(next->debugreg[7])) {
- set_debugreg(next->debugreg[0], 0);
- set_debugreg(next->debugreg[1], 1);
- set_debugreg(next->debugreg[2], 2);
- set_debugreg(next->debugreg[3], 3);
- /* no 4 and 5 */
- set_debugreg(next->debugreg[6], 6);
- set_debugreg(next->debugreg[7], 7);
- }
+ if (unlikely((task_thread_info(next_p)->flags & _TIF_WORK_CTXSW)
+ || test_tsk_thread_flag(prev_p, TIF_IO_BITMAP)))
+ __switch_to_xtra(next_p);
disable_tsc(prev_p, next_p);
+ /* 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
+ */
+ if (next_p->fpu_counter > 5)
+ math_state_restore();
+
return prev_p;
}
(char __user * __user *) regs.edx,
®s);
if (error == 0) {
- task_lock(current);
- current->ptrace &= ~PT_DTRACE;
- task_unlock(current);
/* Make sure we don't return using sysenter.. */
set_thread_flag(TIF_IRET);
}
unsigned long arch_align_stack(unsigned long sp)
{
- if (randomize_va_space)
+ if (!(current->personality & ADDR_NO_RANDOMIZE) && randomize_va_space)
sp -= get_random_int() % 8192;
return sp & ~0xf;
}
git://git.onelab.eu / linux-2.6.git / blobdiff