Merge master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6

[pandora-kernel.git] / kernel / fork.c

diff --git a/kernel/fork.c b/kernel/fork.c
index 628198a..56e4e07 100644 (file)
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -11,7 +11,6 @@
  * management can be a bitch. See 'mm/memory.c': 'copy_page_range()'
  */
 
-#include <linux/config.h>
 #include <linux/slab.h>
 #include <linux/init.h>
 #include <linux/unistd.h>
@@ -194,7 +193,10 @@ static inline int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
 
        down_write(&oldmm->mmap_sem);
        flush_cache_mm(oldmm);
-       down_write(&mm->mmap_sem);
+       /*
+        * Not linked in yet - no deadlock potential:
+        */
+       down_write_nested(&mm->mmap_sem, SINGLE_DEPTH_NESTING);
 
        mm->locked_vm = 0;
        mm->mmap = NULL;
@@ -920,10 +922,6 @@ static inline void rt_mutex_init_task(struct task_struct *p)
        spin_lock_init(&p->pi_lock);
        plist_head_init(&p->pi_waiters, &p->pi_lock);
        p->pi_blocked_on = NULL;
-# ifdef CONFIG_DEBUG_RT_MUTEXES
-       spin_lock_init(&p->held_list_lock);
-       INIT_LIST_HEAD(&p->held_list_head);
-# endif
 #endif
 }
 
@@ -935,13 +933,13 @@ static inline void rt_mutex_init_task(struct task_struct *p)
  * parts of the process environment (as per the clone
  * flags). The actual kick-off is left to the caller.
  */
-static task_t *copy_process(unsigned long clone_flags,
-                                unsigned long stack_start,
-                                struct pt_regs *regs,
-                                unsigned long stack_size,
-                                int __user *parent_tidptr,
-                                int __user *child_tidptr,
-                                int pid)
+static struct task_struct *copy_process(unsigned long clone_flags,
+                                       unsigned long stack_start,
+                                       struct pt_regs *regs,
+                                       unsigned long stack_size,
+                                       int __user *parent_tidptr,
+                                       int __user *child_tidptr,
+                                       int pid)
 {
        int retval;
        struct task_struct *p = NULL;
@@ -973,6 +971,10 @@ static task_t *copy_process(unsigned long clone_flags,
        if (!p)
                goto fork_out;
 
+#ifdef CONFIG_TRACE_IRQFLAGS
+       DEBUG_LOCKS_WARN_ON(!p->hardirqs_enabled);
+       DEBUG_LOCKS_WARN_ON(!p->softirqs_enabled);
+#endif
        retval = -EAGAIN;
        if (atomic_read(&p->user->processes) >=
                        p->signal->rlim[RLIMIT_NPROC].rlim_cur) {
@@ -1047,6 +1049,26 @@ static task_t *copy_process(unsigned long clone_flags,
        }
        mpol_fix_fork_child_flag(p);
 #endif
+#ifdef CONFIG_TRACE_IRQFLAGS
+       p->irq_events = 0;
+       p->hardirqs_enabled = 0;
+       p->hardirq_enable_ip = 0;
+       p->hardirq_enable_event = 0;
+       p->hardirq_disable_ip = _THIS_IP_;
+       p->hardirq_disable_event = 0;
+       p->softirqs_enabled = 1;
+       p->softirq_enable_ip = _THIS_IP_;
+       p->softirq_enable_event = 0;
+       p->softirq_disable_ip = 0;
+       p->softirq_disable_event = 0;
+       p->hardirq_context = 0;
+       p->softirq_context = 0;
+#endif
+#ifdef CONFIG_LOCKDEP
+       p->lockdep_depth = 0; /* no locks held yet */
+       p->curr_chain_key = 0;
+       p->lockdep_recursion = 0;
+#endif
 
        rt_mutex_init_task(p);
 
@@ -1272,9 +1294,9 @@ struct pt_regs * __devinit __attribute__((weak)) idle_regs(struct pt_regs *regs)
        return regs;
 }
 
-task_t * __devinit fork_idle(int cpu)
+struct task_struct * __devinit fork_idle(int cpu)
 {
-       task_t *task;
+       struct task_struct *task;
        struct pt_regs regs;
 
        task = copy_process(CLONE_VM, 0, idle_regs(&regs), 0, NULL, NULL, 0);