#include <linux/init.h>
#include <linux/compiler.h>
#include <linux/delay.h>
+#include <linux/blktrace_api.h>
#include <asm/uaccess.h>
return e;
}
-static int elevator_attach(request_queue_t *q, struct elevator_type *e,
- struct elevator_queue *eq)
+static void *elevator_init_queue(request_queue_t *q, struct elevator_queue *eq)
{
- int ret = 0;
-
- memset(eq, 0, sizeof(*eq));
- eq->ops = &e->ops;
- eq->elevator_type = e;
+ return eq->ops->elevator_init_fn(q, eq);
+}
+static void elevator_attach(request_queue_t *q, struct elevator_queue *eq,
+ void *data)
+{
q->elevator = eq;
-
- if (eq->ops->elevator_init_fn)
- ret = eq->ops->elevator_init_fn(q, eq);
-
- return ret;
+ eq->elevator_data = data;
}
static char chosen_elevator[16];
strcpy(chosen_elevator, "anticipatory");
else
strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
- return 0;
+ return 1;
}
__setup("elevator=", elevator_setup);
+static struct kobj_type elv_ktype;
+
+static elevator_t *elevator_alloc(struct elevator_type *e)
+{
+ elevator_t *eq = kmalloc(sizeof(elevator_t), GFP_KERNEL);
+ if (eq) {
+ memset(eq, 0, sizeof(*eq));
+ eq->ops = &e->ops;
+ eq->elevator_type = e;
+ kobject_init(&eq->kobj);
+ snprintf(eq->kobj.name, KOBJ_NAME_LEN, "%s", "iosched");
+ eq->kobj.ktype = &elv_ktype;
+ mutex_init(&eq->sysfs_lock);
+ } else {
+ elevator_put(e);
+ }
+ return eq;
+}
+
+static void elevator_release(struct kobject *kobj)
+{
+ elevator_t *e = container_of(kobj, elevator_t, kobj);
+ elevator_put(e->elevator_type);
+ kfree(e);
+}
+
int elevator_init(request_queue_t *q, char *name)
{
struct elevator_type *e = NULL;
struct elevator_queue *eq;
int ret = 0;
+ void *data;
INIT_LIST_HEAD(&q->queue_head);
q->last_merge = NULL;
e = elevator_get("noop");
}
- eq = kmalloc(sizeof(struct elevator_queue), GFP_KERNEL);
- if (!eq) {
- elevator_put(e);
+ eq = elevator_alloc(e);
+ if (!eq)
return -ENOMEM;
- }
- ret = elevator_attach(q, e, eq);
- if (ret) {
- kfree(eq);
- elevator_put(e);
+ data = elevator_init_queue(q, eq);
+ if (!data) {
+ kobject_put(&eq->kobj);
+ return -ENOMEM;
}
+ elevator_attach(q, eq, data);
return ret;
}
void elevator_exit(elevator_t *e)
{
+ mutex_lock(&e->sysfs_lock);
if (e->ops->elevator_exit_fn)
e->ops->elevator_exit_fn(e);
+ e->ops = NULL;
+ mutex_unlock(&e->sysfs_lock);
- elevator_put(e->elevator_type);
- e->elevator_type = NULL;
- kfree(e);
+ kobject_put(&e->kobj);
}
/*
{
struct list_head *pos;
unsigned ordseq;
+ int unplug_it = 1;
+
+ blk_add_trace_rq(q, rq, BLK_TA_INSERT);
rq->q = q;
}
list_add_tail(&rq->queuelist, pos);
+ /*
+ * most requeues happen because of a busy condition, don't
+ * force unplug of the queue for that case.
+ */
+ unplug_it = 0;
break;
default:
BUG();
}
- if (blk_queue_plugged(q)) {
+ if (unplug_it && blk_queue_plugged(q)) {
int nrq = q->rq.count[READ] + q->rq.count[WRITE]
- q->in_flight;
* not be passed by new incoming requests
*/
rq->flags |= REQ_STARTED;
+ blk_add_trace_rq(q, rq, BLK_TA_ISSUE);
}
if (!q->boundary_rq || q->boundary_rq == rq) {
}
}
-int elv_register_queue(struct request_queue *q)
+#define to_elv(atr) container_of((atr), struct elv_fs_entry, attr)
+
+static ssize_t
+elv_attr_show(struct kobject *kobj, struct attribute *attr, char *page)
{
- elevator_t *e = q->elevator;
+ elevator_t *e = container_of(kobj, elevator_t, kobj);
+ struct elv_fs_entry *entry = to_elv(attr);
+ ssize_t error;
- e->kobj.parent = kobject_get(&q->kobj);
- if (!e->kobj.parent)
- return -EBUSY;
+ if (!entry->show)
+ return -EIO;
- snprintf(e->kobj.name, KOBJ_NAME_LEN, "%s", "iosched");
- e->kobj.ktype = e->elevator_type->elevator_ktype;
+ mutex_lock(&e->sysfs_lock);
+ error = e->ops ? entry->show(e, page) : -ENOENT;
+ mutex_unlock(&e->sysfs_lock);
+ return error;
+}
- return kobject_register(&e->kobj);
+static ssize_t
+elv_attr_store(struct kobject *kobj, struct attribute *attr,
+ const char *page, size_t length)
+{
+ elevator_t *e = container_of(kobj, elevator_t, kobj);
+ struct elv_fs_entry *entry = to_elv(attr);
+ ssize_t error;
+
+ if (!entry->store)
+ return -EIO;
+
+ mutex_lock(&e->sysfs_lock);
+ error = e->ops ? entry->store(e, page, length) : -ENOENT;
+ mutex_unlock(&e->sysfs_lock);
+ return error;
}
-void elv_unregister_queue(struct request_queue *q)
+static struct sysfs_ops elv_sysfs_ops = {
+ .show = elv_attr_show,
+ .store = elv_attr_store,
+};
+
+static struct kobj_type elv_ktype = {
+ .sysfs_ops = &elv_sysfs_ops,
+ .release = elevator_release,
+};
+
+int elv_register_queue(struct request_queue *q)
{
- if (q) {
- elevator_t *e = q->elevator;
- kobject_unregister(&e->kobj);
- kobject_put(&q->kobj);
+ elevator_t *e = q->elevator;
+ int error;
+
+ e->kobj.parent = &q->kobj;
+
+ error = kobject_add(&e->kobj);
+ if (!error) {
+ struct elv_fs_entry *attr = e->elevator_type->elevator_attrs;
+ if (attr) {
+ while (attr->attr.name) {
+ if (sysfs_create_file(&e->kobj, &attr->attr))
+ break;
+ attr++;
+ }
+ }
+ kobject_uevent(&e->kobj, KOBJ_ADD);
}
+ return error;
+}
+
+static void __elv_unregister_queue(elevator_t *e)
+{
+ kobject_uevent(&e->kobj, KOBJ_REMOVE);
+ kobject_del(&e->kobj);
+}
+
+void elv_unregister_queue(struct request_queue *q)
+{
+ if (q)
+ __elv_unregister_queue(q->elevator);
}
int elv_register(struct elevator_type *e)
{
spin_lock_irq(&elv_list_lock);
- if (elevator_find(e->elevator_name))
- BUG();
+ BUG_ON(elevator_find(e->elevator_name));
list_add_tail(&e->list, &elv_list);
spin_unlock_irq(&elv_list_lock);
/*
* 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);
* need for the new one. this way we have a chance of going back to the old
* one, if the new one fails init for some reason.
*/
-static void elevator_switch(request_queue_t *q, struct elevator_type *new_e)
+static int elevator_switch(request_queue_t *q, struct elevator_type *new_e)
{
elevator_t *old_elevator, *e;
+ void *data;
/*
* Allocate new elevator
*/
- e = kmalloc(sizeof(elevator_t), GFP_KERNEL);
+ e = elevator_alloc(new_e);
if (!e)
- goto error;
+ return 0;
+
+ data = elevator_init_queue(q, e);
+ if (!data) {
+ kobject_put(&e->kobj);
+ return 0;
+ }
/*
* Turn on BYPASS and drain all requests w/ elevator private data
elv_drain_elevator(q);
}
- spin_unlock_irq(q->queue_lock);
-
/*
- * unregister old elevator data
+ * Remember old elevator.
*/
- elv_unregister_queue(q);
old_elevator = q->elevator;
/*
* attach and start new elevator
*/
- if (elevator_attach(q, new_e, e))
- goto fail;
+ elevator_attach(q, e, data);
+
+ spin_unlock_irq(q->queue_lock);
+
+ __elv_unregister_queue(old_elevator);
if (elv_register_queue(q))
goto fail_register;
*/
elevator_exit(old_elevator);
clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- return;
+ return 1;
fail_register:
/*
*/
elevator_exit(e);
e = NULL;
-fail:
q->elevator = old_elevator;
elv_register_queue(q);
clear_bit(QUEUE_FLAG_ELVSWITCH, &q->queue_flags);
- kfree(e);
-error:
- elevator_put(new_e);
- printk(KERN_ERR "elevator: switch to %s failed\n",new_e->elevator_name);
+ if (e)
+ kobject_put(&e->kobj);
+ return 0;
}
ssize_t elv_iosched_store(request_queue_t *q, const char *name, size_t count)
return count;
}
- elevator_switch(q, e);
+ if (!elevator_switch(q, e))
+ printk(KERN_ERR "elevator: switch to %s failed\n",elevator_name);
return count;
}
EXPORT_SYMBOL(elv_dispatch_sort);
EXPORT_SYMBOL(elv_add_request);
EXPORT_SYMBOL(__elv_add_request);
-EXPORT_SYMBOL(elv_requeue_request);
EXPORT_SYMBOL(elv_next_request);
EXPORT_SYMBOL(elv_dequeue_request);
EXPORT_SYMBOL(elv_queue_empty);
-EXPORT_SYMBOL(elv_completed_request);
EXPORT_SYMBOL(elevator_exit);
EXPORT_SYMBOL(elevator_init);
git.openpandora.org / pandora-kernel.git / blobdiff