linux-toradex.git/fs/ioprio.c, branch v2.6.22.2

[PATCH] pid: replace do/while_each_task_pid with do/while_each_pid_task

2007-02-12T17:48:32+00:00

There isn't any real advantage to this change except that it allows the old
functions to be removed.  Which is easier on maintenance and puts the code in
a more uniform style.

Signed-off-by: Eric W. Biederman 
Cc: Alan Cox 
Cc: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] block layer: ioprio_best function fix

2006-10-12T13:09:51+00:00

Currently ioprio_best function first checks wethere aioprio or bioprio equals
IOPRIO_CLASS_NONE (ioprio_valid() macros does that) and if it is so it returns
bioprio/aioprio appropriately. Thus the next four lines, that set aclass/bclass
to IOPRIO_CLASS_BE, if aclass/bclass == IOPRIO_CLASS_NONE, are never executed.

The second problem: if aioprio from class IOPRIO_CLASS_NONE and bioprio from
class IOPRIO_CLASS_IDLE are passed to ioprio_best function, it will return
IOPRIO_CLASS_IDLE. It means that during __make_request we can merge two
requests and set the priority of merged request to IDLE, while one of
the initial requests originates from a process with NONE (default) priority.
So we can get a situation when a process with default ioprio will experience
IO starvation, while there is no process from real-time class in the system.

Just removing ioprio_valid check should correct situation.

Signed-off-by: Vasily Tarasov 
Signed-off-by: Jens Axboe

[PATCH] Update axboe@suse.de email address

2006-09-30T18:52:34+00:00

As people often look for the copyright in files to see who to mail,
update the link to a neutral one.

Signed-off-by: Jens Axboe

[PATCH] Don't need to disable interrupts for tasklist_lock

2006-09-30T18:31:18+00:00

Signed-off-by: Oleg Nesterov 
Signed-off-by: Jens Axboe

[PATCH] cfq-iosched: kill cfq_exit_lock

2006-09-30T18:29:36+00:00

cfq_exit_lock is protecting two things now:

- The per-ioc rbtree of cfq_io_contexts

- The per-cfqd linked list of cfq_io_contexts

The per-cfqd linked list can be protected by the queue lock, as it is (by
definition) per cfqd as the queue lock is.

The per-ioc rbtree is mainly used and updated by the process itself only.
The only outside use is the io priority changing. If we move the
priority changing to not browsing the rbtree, we can remove any locking
from the rbtree updates and lookup completely. Let the sys_ioprio syscall
just mark processes as having the iopriority changed and lazily update
the private cfq io contexts the next time io is queued, and we can
remove this locking as well.

Signed-off-by: Jens Axboe

[PATCH] uninline ioprio_best()

2006-08-21T08:02:50+00:00

Saves 376 bytes (5 callers) for me.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Jens Axboe

[PATCH] Fix current_io_context() vs set_task_ioprio() race

2006-08-21T06:34:15+00:00

I know nothing about io scheduler, but I suspect set_task_ioprio() is not safe.

current_io_context() initializes "struct io_context", then sets ->io_context.
set_task_ioprio() running on another cpu may see the changes out of order, so
->set_ioprio(ioc) may use io_context which was not initialized properly.

Signed-off-by: Oleg Nesterov 
Signed-off-by: Jens Axboe

[PATCH] sys_ioprio_set: minor do_each_thread+break fix

2006-08-21T06:33:23+00:00

From include/linux/sched.h:

         * Careful: do_each_thread/while_each_thread is a double loop so
         *          'break' will not work as expected - use goto instead.
         */

Signed-off-by: Oleg Nesterov 
Signed-off-by: Jens Axboe

[PATCH] SELinux: Add security hook definition for getioprio and insert hooks

2006-06-30T18:25:37+00:00

Add a new security hook definition for the sys_ioprio_get operation.  At
present, the SELinux hook function implementation for this hook is
identical to the getscheduler implementation but a separate hook is
introduced to allow this check to be specialized in the future if
necessary.

This patch also creates a helper function get_task_ioprio which handles the
access check in addition to retrieving the ioprio value for the task.

Signed-off-by: David Quigley 
Acked-by: Stephen Smalley 
Signed-off-by: James Morris 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] lsm: add task_setioprio hook

2006-06-23T14:42:53+00:00

Implement an LSM hook for setting a task's IO priority, similar to the hook
for setting a tasks's nice value.

A previous version of this LSM hook was included in an older version of
multiadm by Jan Engelhardt, although I don't recall it being submitted
upstream.

Also included is the corresponding SELinux hook, which re-uses the setsched
permission in the proccess class.

Signed-off-by: James Morris 
Acked-by:  Stephen Smalley 
Cc: Jan Engelhardt 
Cc: Chris Wright 
Cc: Jens Axboe 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds