[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]

Re: [dm-devel] Re: [PATCH resubmit] do_mount: reduce stack consumption



Andrew Morton wrote:
Neil Brown <neilb suse de> wrote:

...
Reduce stack usage with stacked block devices

...
diff ./include/linux/sched.h~current~ ./include/linux/sched.h
--- ./include/linux/sched.h~current~	2005-11-07 10:01:36.000000000 +1100
+++ ./include/linux/sched.h	2005-11-07 10:02:23.000000000 +1100
@@ -829,6 +829,9 @@ struct task_struct {
/* journalling filesystem info */
	void *journal_info;

+/* stacked block device info */
+	struct bio *bio_list, **bio_tail;
+
/* VM state */
	struct reclaim_state *reclaim_state;



More state in the task_strut is a bit sad, but not nearly as sad as deep
recursion in our deepest codepath..

Possibly one could do:

struct make_request_state {
	struct bio *bio_list;
	struct bio **bio_tail;
};

and stick a `struct make_request_state *' into the task_struct and actually
allocate the thing on the stack.  That's not much nicer though.

Possibly it could go into struct io_context?

--
SUSE Labs, Novell Inc.

Send instant messages to your online friends http://au.messenger.yahoo.com
[Date Prev][Date Next]   [Thread Prev][Thread Next]   [Thread Index] [Date Index] [Author Index]