[PATCH] Update cfq io scheduler to time sliced design

This updates the CFQ io scheduler to the new time sliced design (cfq
v3).  It provides full process fairness, while giving excellent
aggregate system throughput even for many competing processes.  It
supports io priorities, either inherited from the cpu nice value or set
directly with the ioprio_get/set syscalls.  The latter closely mimic
set/getpriority.

This import is based on my latest from -mm.

Signed-off-by: Jens Axboe <axboe@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 5 insertions, 0 deletions

diff --git a/kernel/fork.c b/kernel/fork.c
index 2c7806873bfd..cdef6cea8900 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1090,6 +1090,11 @@ static task_t *copy_process(unsigned long clone_flags,
                 spin_unlock(&current->sighand->siglock);
         }
 
+        /*
+         * inherit ioprio
+         */
+        p->ioprio = current->ioprio;
+
         SET_LINKS(p);
         if (unlikely(p->ptrace & PT_PTRACED))
                 __ptrace_link(p, current->parent);