summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorAl Viro <viro@zeniv.linux.org.uk>2006-03-18 13:21:20 -0500
committerAl Viro <viro@zeniv.linux.org.uk>2006-03-18 18:34:12 -0500
commite17a9489b4a686bb5e9615e1d375c67619cb99c5 (patch)
treee6574d24ad8f16fefe7663c91cf19109e48f8c6c
parent25975f863b0fd42c58109e253e7a4c65d9fdaf48 (diff)
downloadlinux-e17a9489b4a686bb5e9615e1d375c67619cb99c5.tar.gz
linux-e17a9489b4a686bb5e9615e1d375c67619cb99c5.tar.bz2
linux-e17a9489b4a686bb5e9615e1d375c67619cb99c5.zip
[PATCH] stop elv_unregister() from rogering other iosched's data, fix locking
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
-rw-r--r--block/as-iosched.c7
-rw-r--r--block/cfq-iosched.c8
-rw-r--r--block/elevator.c24
-rw-r--r--include/linux/elevator.h1
4 files changed, 25 insertions, 15 deletions
diff --git a/block/as-iosched.c b/block/as-iosched.c
index 8da3cf66894c..d2ee2af44b58 100644
--- a/block/as-iosched.c
+++ b/block/as-iosched.c
@@ -195,6 +195,12 @@ static void free_as_io_context(struct as_io_context *aic)
kfree(aic);
}
+static void as_trim(struct io_context *ioc)
+{
+ kfree(ioc->aic);
+ ioc->aic = NULL;
+}
+
/* Called when the task exits */
static void exit_as_io_context(struct as_io_context *aic)
{
@@ -1860,6 +1866,7 @@ static struct elevator_type iosched_as = {
.elevator_may_queue_fn = as_may_queue,
.elevator_init_fn = as_init_queue,
.elevator_exit_fn = as_exit_queue,
+ .trim = as_trim,
},
.elevator_ktype = &as_ktype,
diff --git a/block/cfq-iosched.c b/block/cfq-iosched.c
index 521c56d4fdbc..7102bafc98b3 100644
--- a/block/cfq-iosched.c
+++ b/block/cfq-iosched.c
@@ -1211,6 +1211,13 @@ static void cfq_free_io_context(struct cfq_io_context *cic)
kmem_cache_free(cfq_ioc_pool, cic);
}
+static void cfq_trim(struct io_context *ioc)
+{
+ ioc->set_ioprio = NULL;
+ if (ioc->cic)
+ cfq_free_io_context(ioc->cic);
+}
+
/*
* Called with interrupts disabled
*/
@@ -2472,6 +2479,7 @@ static struct elevator_type iosched_cfq = {
.elevator_may_queue_fn = cfq_may_queue,
.elevator_init_fn = cfq_init_queue,
.elevator_exit_fn = cfq_exit_queue,
+ .trim = cfq_trim,
},
.elevator_ktype = &cfq_ktype,
.elevator_name = "cfq",
diff --git a/block/elevator.c b/block/elevator.c
index 24b702d649a9..0232df2b16e6 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -675,21 +675,15 @@ void elv_unregister(struct elevator_type *e)
/*
* Iterate every thread in the process to remove the io contexts.
*/
- read_lock(&tasklist_lock);
- do_each_thread(g, p) {
- struct io_context *ioc = p->io_context;
- if (ioc && ioc->cic) {
- ioc->cic->exit(ioc->cic);
- ioc->cic->dtor(ioc->cic);
- ioc->cic = NULL;
- }
- if (ioc && ioc->aic) {
- ioc->aic->exit(ioc->aic);
- ioc->aic->dtor(ioc->aic);
- ioc->aic = NULL;
- }
- } while_each_thread(g, p);
- read_unlock(&tasklist_lock);
+ if (e->ops.trim) {
+ read_lock(&tasklist_lock);
+ do_each_thread(g, p) {
+ task_lock(p);
+ e->ops.trim(p->io_context);
+ task_unlock(p);
+ } while_each_thread(g, p);
+ read_unlock(&tasklist_lock);
+ }
spin_lock_irq(&elv_list_lock);
list_del_init(&e->list);
diff --git a/include/linux/elevator.h b/include/linux/elevator.h
index 18cf1f3e1184..f65766ef0532 100644
--- a/include/linux/elevator.h
+++ b/include/linux/elevator.h
@@ -48,6 +48,7 @@ struct elevator_ops
elevator_init_fn *elevator_init_fn;
elevator_exit_fn *elevator_exit_fn;
+ void (*trim)(struct io_context *);
};
#define ELV_NAME_MAX (16)