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Diffstat (limited to 'kernel/fork.c')
-rw-r--r--kernel/fork.c90
1 files changed, 69 insertions, 21 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 8ca1a14cdc8..2b55b74cd99 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -51,6 +51,7 @@
#include <linux/random.h>
#include <linux/tty.h>
#include <linux/proc_fs.h>
+#include <linux/blkdev.h>
#include <asm/pgtable.h>
#include <asm/pgalloc.h>
@@ -324,7 +325,7 @@ static inline int mm_alloc_pgd(struct mm_struct * mm)
static inline void mm_free_pgd(struct mm_struct * mm)
{
- pgd_free(mm->pgd);
+ pgd_free(mm, mm->pgd);
}
#else
#define dup_mmap(mm, oldmm) (0)
@@ -392,6 +393,7 @@ void fastcall __mmdrop(struct mm_struct *mm)
destroy_context(mm);
free_mm(mm);
}
+EXPORT_SYMBOL_GPL(__mmdrop);
/*
* Decrement the use count and release all resources for an mm.
@@ -791,6 +793,31 @@ out:
return error;
}
+static int copy_io(unsigned long clone_flags, struct task_struct *tsk)
+{
+#ifdef CONFIG_BLOCK
+ struct io_context *ioc = current->io_context;
+
+ if (!ioc)
+ return 0;
+ /*
+ * Share io context with parent, if CLONE_IO is set
+ */
+ if (clone_flags & CLONE_IO) {
+ tsk->io_context = ioc_task_link(ioc);
+ if (unlikely(!tsk->io_context))
+ return -ENOMEM;
+ } else if (ioprio_valid(ioc->ioprio)) {
+ tsk->io_context = alloc_io_context(GFP_KERNEL, -1);
+ if (unlikely(!tsk->io_context))
+ return -ENOMEM;
+
+ tsk->io_context->ioprio = ioc->ioprio;
+ }
+#endif
+ return 0;
+}
+
/*
* Helper to unshare the files of the current task.
* We don't want to expose copy_files internals to
@@ -1045,6 +1072,10 @@ static struct task_struct *copy_process(unsigned long clone_flags,
copy_flags(clone_flags, p);
INIT_LIST_HEAD(&p->children);
INIT_LIST_HEAD(&p->sibling);
+#ifdef CONFIG_PREEMPT_RCU
+ p->rcu_read_lock_nesting = 0;
+ p->rcu_flipctr_idx = 0;
+#endif /* #ifdef CONFIG_PREEMPT_RCU */
p->vfork_done = NULL;
spin_lock_init(&p->alloc_lock);
@@ -1059,6 +1090,11 @@ static struct task_struct *copy_process(unsigned long clone_flags,
p->prev_utime = cputime_zero;
p->prev_stime = cputime_zero;
+#ifdef CONFIG_DETECT_SOFTLOCKUP
+ p->last_switch_count = 0;
+ p->last_switch_timestamp = 0;
+#endif
+
#ifdef CONFIG_TASK_XACCT
p->rchar = 0; /* I/O counter: bytes read */
p->wchar = 0; /* I/O counter: bytes written */
@@ -1082,6 +1118,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#ifdef CONFIG_SECURITY
p->security = NULL;
#endif
+ p->cap_bset = current->cap_bset;
p->io_context = NULL;
p->audit_context = NULL;
cgroup_fork(p);
@@ -1147,15 +1184,17 @@ static struct task_struct *copy_process(unsigned long clone_flags,
goto bad_fork_cleanup_mm;
if ((retval = copy_namespaces(clone_flags, p)))
goto bad_fork_cleanup_keys;
+ if ((retval = copy_io(clone_flags, p)))
+ goto bad_fork_cleanup_namespaces;
retval = copy_thread(0, clone_flags, stack_start, stack_size, p, regs);
if (retval)
- goto bad_fork_cleanup_namespaces;
+ goto bad_fork_cleanup_io;
if (pid != &init_struct_pid) {
retval = -ENOMEM;
pid = alloc_pid(task_active_pid_ns(p));
if (!pid)
- goto bad_fork_cleanup_namespaces;
+ goto bad_fork_cleanup_io;
if (clone_flags & CLONE_NEWPID) {
retval = pid_ns_prepare_proc(task_active_pid_ns(p));
@@ -1196,6 +1235,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
#ifdef TIF_SYSCALL_EMU
clear_tsk_thread_flag(p, TIF_SYSCALL_EMU);
#endif
+ clear_all_latency_tracing(p);
/* Our parent execution domain becomes current domain
These must match for thread signalling to apply */
@@ -1224,9 +1264,6 @@ static struct task_struct *copy_process(unsigned long clone_flags,
/* Need tasklist lock for parent etc handling! */
write_lock_irq(&tasklist_lock);
- /* for sys_ioprio_set(IOPRIO_WHO_PGRP) */
- p->ioprio = current->ioprio;
-
/*
* The task hasn't been attached yet, so its cpus_allowed mask will
* not be changed, nor will its assigned CPU.
@@ -1237,6 +1274,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
* parent's CPU). This avoids alot of nasty races.
*/
p->cpus_allowed = current->cpus_allowed;
+ p->rt.nr_cpus_allowed = current->rt.nr_cpus_allowed;
if (unlikely(!cpu_isset(task_cpu(p), p->cpus_allowed) ||
!cpu_online(task_cpu(p))))
set_task_cpu(p, smp_processor_id());
@@ -1292,23 +1330,14 @@ static struct task_struct *copy_process(unsigned long clone_flags,
__ptrace_link(p, current->parent);
if (thread_group_leader(p)) {
- if (clone_flags & CLONE_NEWPID) {
+ if (clone_flags & CLONE_NEWPID)
p->nsproxy->pid_ns->child_reaper = p;
- p->signal->tty = NULL;
- set_task_pgrp(p, p->pid);
- set_task_session(p, p->pid);
- attach_pid(p, PIDTYPE_PGID, pid);
- attach_pid(p, PIDTYPE_SID, pid);
- } else {
- p->signal->tty = current->signal->tty;
- set_task_pgrp(p, task_pgrp_nr(current));
- set_task_session(p, task_session_nr(current));
- attach_pid(p, PIDTYPE_PGID,
- task_pgrp(current));
- attach_pid(p, PIDTYPE_SID,
- task_session(current));
- }
+ p->signal->tty = current->signal->tty;
+ set_task_pgrp(p, task_pgrp_nr(current));
+ set_task_session(p, task_session_nr(current));
+ attach_pid(p, PIDTYPE_PGID, task_pgrp(current));
+ attach_pid(p, PIDTYPE_SID, task_session(current));
list_add_tail_rcu(&p->tasks, &init_task.tasks);
__get_cpu_var(process_counts)++;
}
@@ -1326,6 +1355,8 @@ static struct task_struct *copy_process(unsigned long clone_flags,
bad_fork_free_pid:
if (pid != &init_struct_pid)
free_pid(pid);
+bad_fork_cleanup_io:
+ put_io_context(p->io_context);
bad_fork_cleanup_namespaces:
exit_task_namespaces(p);
bad_fork_cleanup_keys:
@@ -1420,6 +1451,23 @@ long do_fork(unsigned long clone_flags,
int trace = 0;
long nr;
+ /*
+ * We hope to recycle these flags after 2.6.26
+ */
+ if (unlikely(clone_flags & CLONE_STOPPED)) {
+ static int __read_mostly count = 100;
+
+ if (count > 0 && printk_ratelimit()) {
+ char comm[TASK_COMM_LEN];
+
+ count--;
+ printk(KERN_INFO "fork(): process `%s' used deprecated "
+ "clone flags 0x%lx\n",
+ get_task_comm(comm, current),
+ clone_flags & CLONE_STOPPED);
+ }
+ }
+
if (unlikely(current->ptrace)) {
trace = fork_traceflag (clone_flags);
if (trace)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2025-04-04 00:23:03 +0000