Commit 32ecb1f2 authored by Oleg Nesterov's avatar Oleg Nesterov Committed by Linus Torvalds
Browse files

coredump: turn mm->core_startup_done into the pointer to struct core_state 



mm->core_startup_done points to "struct completion startup_done" allocated
on the coredump_wait()'s stack.  Introduce the new structure, core_state,
which holds this "struct completion".  This way we can add more info
visible to the threads participating in coredump without enlarging
mm_struct.

No changes in affected .o files.

Signed-off-by: default avatarOleg Nesterov <oleg@tv-sign.ru>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 24d5288f

fs/exec.c

+4 −4
Original line number Diff line number Diff line
@@ -1597,13 +1597,13 @@ static int coredump_wait(int exit_code) 
{

	struct task_struct *tsk = current;

	struct mm_struct *mm = tsk->mm;

	struct completion startup_done;

	struct core_state core_state;

	struct completion *vfork_done;

	int core_waiters;



	init_completion(&mm->core_done);

	init_completion(&startup_done);

	mm->core_startup_done = &startup_done;

	init_completion(&core_state.startup);

	mm->core_state = &core_state;



	core_waiters = zap_threads(tsk, mm, exit_code);

	up_write(&mm->mmap_sem);
@@ -1622,7 +1622,7 @@ static int coredump_wait(int exit_code) 
	}



	if (core_waiters)

		wait_for_completion(&startup_done);

		wait_for_completion(&core_state.startup);

fail:

	BUG_ON(mm->core_waiters);

	return core_waiters;

include/linux/mm_types.h

+6 −1
Original line number Diff line number Diff line
@@ -159,6 +159,10 @@ struct vm_area_struct { 
#endif

};



struct core_state {

	struct completion startup;

};



struct mm_struct {

	struct vm_area_struct * mmap;		/* list of VMAs */

	struct rb_root mm_rb;
@@ -220,7 +224,8 @@ struct mm_struct { 
	unsigned long flags; /* Must use atomic bitops to access the bits */



	/* coredumping support */

	struct completion *core_startup_done, core_done;

	struct core_state *core_state;

	struct completion core_done;



	/* aio bits */

	rwlock_t		ioctx_list_lock;	/* aio lock */

kernel/exit.c

+1 −1
Original line number Diff line number Diff line
@@ -680,7 +680,7 @@ static void exit_mm(struct task_struct * tsk) 
		up_read(&mm->mmap_sem);

		down_write(&mm->mmap_sem);

		if (!--mm->core_waiters)

			complete(mm->core_startup_done);

			complete(&mm->core_state->startup);

		up_write(&mm->mmap_sem);



		wait_for_completion(&mm->core_done);

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