task_struct cleanup: move binfmt field to mm_struct
Because the binfmt is not different between threads in the same process,
it can be moved from task_struct to mm_struct. And binfmt moudle is
handled per mm_struct instead of task_struct.
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/kernel/fork.c b/kernel/fork.c
index e49f181..266c6af 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -518,6 +518,8 @@
spin_unlock(&mmlist_lock);
}
put_swap_token(mm);
+ if (mm->binfmt)
+ module_put(mm->binfmt->module);
mmdrop(mm);
}
}
@@ -643,9 +645,14 @@
mm->hiwater_rss = get_mm_rss(mm);
mm->hiwater_vm = mm->total_vm;
+ if (mm->binfmt && !try_module_get(mm->binfmt->module))
+ goto free_pt;
+
return mm;
free_pt:
+ /* don't put binfmt in mmput, we haven't got module yet */
+ mm->binfmt = NULL;
mmput(mm);
fail_nomem:
@@ -1037,9 +1044,6 @@
if (!try_module_get(task_thread_info(p)->exec_domain->module))
goto bad_fork_cleanup_count;
- if (p->binfmt && !try_module_get(p->binfmt->module))
- goto bad_fork_cleanup_put_domain;
-
p->did_exec = 0;
delayacct_tsk_init(p); /* Must remain after dup_task_struct() */
copy_flags(clone_flags, p);
@@ -1327,9 +1331,6 @@
#endif
cgroup_exit(p, cgroup_callbacks_done);
delayacct_tsk_free(p);
- if (p->binfmt)
- module_put(p->binfmt->module);
-bad_fork_cleanup_put_domain:
module_put(task_thread_info(p)->exec_domain->module);
bad_fork_cleanup_count:
atomic_dec(&p->cred->user->processes);
