From d2ccde1c8e90d38cee87a1b0309ad2827f3fd30d Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Mon, 11 Dec 2023 02:45:28 +0000
Subject: [PATCH] add boot partition size
---
kernel/block/elevator.c | 674 +++++++++++++------------------------------------------
1 files changed, 163 insertions(+), 511 deletions(-)
diff --git a/kernel/block/elevator.c b/kernel/block/elevator.c
index 80e632d..f762b2a 100644
--- a/kernel/block/elevator.c
+++ b/kernel/block/elevator.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Block device elevator/IO-scheduler.
*
@@ -41,6 +42,7 @@
#include "blk.h"
#include "blk-mq-sched.h"
+#include "blk-pm.h"
#include "blk-wbt.h"
static DEFINE_SPINLOCK(elv_list_lock);
@@ -60,10 +62,8 @@
struct request_queue *q = rq->q;
struct elevator_queue *e = q->elevator;
- if (e->uses_mq && e->type->ops.mq.allow_merge)
- return e->type->ops.mq.allow_merge(q, rq, bio);
- else if (!e->uses_mq && e->type->ops.sq.elevator_allow_bio_merge_fn)
- return e->type->ops.sq.elevator_allow_bio_merge_fn(q, rq, bio);
+ if (e->type->ops.allow_merge)
+ return e->type->ops.allow_merge(q, rq, bio);
return 1;
}
@@ -83,8 +83,26 @@
}
EXPORT_SYMBOL(elv_bio_merge_ok);
-static bool elevator_match(const struct elevator_type *e, const char *name)
+static inline bool elv_support_features(unsigned int elv_features,
+ unsigned int required_features)
{
+ return (required_features & elv_features) == required_features;
+}
+
+/**
+ * elevator_match - Test an elevator name and features
+ * @e: Scheduler to test
+ * @name: Elevator name to test
+ * @required_features: Features that the elevator must provide
+ *
+ * Return true if the elevator @e name matches @name and if @e provides all
+ * the features specified by @required_features.
+ */
+static bool elevator_match(const struct elevator_type *e, const char *name,
+ unsigned int required_features)
+{
+ if (!elv_support_features(e->elevator_features, required_features))
+ return false;
if (!strcmp(e->elevator_name, name))
return true;
if (e->elevator_alias && !strcmp(e->elevator_alias, name))
@@ -93,15 +111,21 @@
return false;
}
-/*
- * Return scheduler with name 'name' and with matching 'mq capability
+/**
+ * elevator_find - Find an elevator
+ * @name: Name of the elevator to find
+ * @required_features: Features that the elevator must provide
+ *
+ * Return the first registered scheduler with name @name and supporting the
+ * features @required_features and NULL otherwise.
*/
-static struct elevator_type *elevator_find(const char *name, bool mq)
+static struct elevator_type *elevator_find(const char *name,
+ unsigned int required_features)
{
struct elevator_type *e;
list_for_each_entry(e, &elv_list, list) {
- if (elevator_match(e, name) && (mq == e->uses_mq))
+ if (elevator_match(e, name, required_features))
return e;
}
@@ -120,12 +144,12 @@
spin_lock(&elv_list_lock);
- e = elevator_find(name, q->mq_ops != NULL);
+ e = elevator_find(name, q->required_elevator_features);
if (!e && try_loading) {
spin_unlock(&elv_list_lock);
request_module("%s-iosched", name);
spin_lock(&elv_list_lock);
- e = elevator_find(name, q->mq_ops != NULL);
+ e = elevator_find(name, q->required_elevator_features);
}
if (e && !try_module_get(e->elevator_owner))
@@ -133,40 +157,6 @@
spin_unlock(&elv_list_lock);
return e;
-}
-
-static char chosen_elevator[ELV_NAME_MAX];
-
-static int __init elevator_setup(char *str)
-{
- /*
- * Be backwards-compatible with previous kernels, so users
- * won't get the wrong elevator.
- */
- strncpy(chosen_elevator, str, sizeof(chosen_elevator) - 1);
- return 1;
-}
-
-__setup("elevator=", elevator_setup);
-
-/* called during boot to load the elevator chosen by the elevator param */
-void __init load_default_elevator_module(void)
-{
- struct elevator_type *e;
-
- if (!chosen_elevator[0])
- return;
-
- /*
- * Boot parameter is deprecated, we haven't supported that for MQ.
- * Only look for non-mq schedulers from here.
- */
- spin_lock(&elv_list_lock);
- e = elevator_find(chosen_elevator, false);
- spin_unlock(&elv_list_lock);
-
- if (!e)
- request_module("%s-iosched", chosen_elevator);
}
static struct kobj_type elv_ktype;
@@ -184,7 +174,6 @@
kobject_init(&eq->kobj, &elv_ktype);
mutex_init(&eq->sysfs_lock);
hash_init(eq->hash);
- eq->uses_mq = e->uses_mq;
return eq;
}
@@ -199,54 +188,10 @@
kfree(e);
}
-/*
- * Use the default elevator specified by config boot param for non-mq devices,
- * or by config option. Don't try to load modules as we could be running off
- * async and request_module() isn't allowed from async.
- */
-int elevator_init(struct request_queue *q)
-{
- struct elevator_type *e = NULL;
- int err = 0;
-
- /*
- * q->sysfs_lock must be held to provide mutual exclusion between
- * elevator_switch() and here.
- */
- mutex_lock(&q->sysfs_lock);
- if (unlikely(q->elevator))
- goto out_unlock;
-
- if (*chosen_elevator) {
- e = elevator_get(q, chosen_elevator, false);
- if (!e)
- printk(KERN_ERR "I/O scheduler %s not found\n",
- chosen_elevator);
- }
-
- if (!e)
- e = elevator_get(q, CONFIG_DEFAULT_IOSCHED, false);
- if (!e) {
- printk(KERN_ERR
- "Default I/O scheduler not found. Using noop.\n");
- e = elevator_get(q, "noop", false);
- }
-
- err = e->ops.sq.elevator_init_fn(q, e);
- if (err)
- elevator_put(e);
-out_unlock:
- mutex_unlock(&q->sysfs_lock);
- return err;
-}
-
-void elevator_exit(struct request_queue *q, struct elevator_queue *e)
+void __elevator_exit(struct request_queue *q, struct elevator_queue *e)
{
mutex_lock(&e->sysfs_lock);
- if (e->uses_mq && e->type->ops.mq.exit_sched)
- blk_mq_exit_sched(q, e);
- else if (!e->uses_mq && e->type->ops.sq.elevator_exit_fn)
- e->type->ops.sq.elevator_exit_fn(e);
+ blk_mq_exit_sched(q, e);
mutex_unlock(&e->sysfs_lock);
kobject_put(&e->kobj);
@@ -355,68 +300,6 @@
}
EXPORT_SYMBOL(elv_rb_find);
-/*
- * Insert rq into dispatch queue of q. Queue lock must be held on
- * entry. rq is sort instead into the dispatch queue. To be used by
- * specific elevators.
- */
-void elv_dispatch_sort(struct request_queue *q, struct request *rq)
-{
- sector_t boundary;
- struct list_head *entry;
-
- if (q->last_merge == rq)
- q->last_merge = NULL;
-
- elv_rqhash_del(q, rq);
-
- q->nr_sorted--;
-
- boundary = q->end_sector;
- list_for_each_prev(entry, &q->queue_head) {
- struct request *pos = list_entry_rq(entry);
-
- if (req_op(rq) != req_op(pos))
- break;
- if (rq_data_dir(rq) != rq_data_dir(pos))
- break;
- if (pos->rq_flags & (RQF_STARTED | RQF_SOFTBARRIER))
- break;
- if (blk_rq_pos(rq) >= boundary) {
- if (blk_rq_pos(pos) < boundary)
- continue;
- } else {
- if (blk_rq_pos(pos) >= boundary)
- break;
- }
- if (blk_rq_pos(rq) >= blk_rq_pos(pos))
- break;
- }
-
- list_add(&rq->queuelist, entry);
-}
-EXPORT_SYMBOL(elv_dispatch_sort);
-
-/*
- * Insert rq into dispatch queue of q. Queue lock must be held on
- * entry. rq is added to the back of the dispatch queue. To be used by
- * specific elevators.
- */
-void elv_dispatch_add_tail(struct request_queue *q, struct request *rq)
-{
- if (q->last_merge == rq)
- q->last_merge = NULL;
-
- elv_rqhash_del(q, rq);
-
- q->nr_sorted--;
-
- q->end_sector = rq_end_sector(rq);
- q->boundary_rq = rq;
- list_add_tail(&rq->queuelist, &q->queue_head);
-}
-EXPORT_SYMBOL(elv_dispatch_add_tail);
-
enum elv_merge elv_merge(struct request_queue *q, struct request **req,
struct bio *bio)
{
@@ -453,13 +336,14 @@
__rq = elv_rqhash_find(q, bio->bi_iter.bi_sector);
if (__rq && elv_bio_merge_ok(__rq, bio)) {
*req = __rq;
+
+ if (blk_discard_mergable(__rq))
+ return ELEVATOR_DISCARD_MERGE;
return ELEVATOR_BACK_MERGE;
}
- if (e->uses_mq && e->type->ops.mq.request_merge)
- return e->type->ops.mq.request_merge(q, req, bio);
- else if (!e->uses_mq && e->type->ops.sq.elevator_merge_fn)
- return e->type->ops.sq.elevator_merge_fn(q, req, bio);
+ if (e->type->ops.request_merge)
+ return e->type->ops.request_merge(q, req, bio);
return ELEVATOR_NO_MERGE;
}
@@ -510,10 +394,8 @@
{
struct elevator_queue *e = q->elevator;
- if (e->uses_mq && e->type->ops.mq.request_merged)
- e->type->ops.mq.request_merged(q, rq, type);
- else if (!e->uses_mq && e->type->ops.sq.elevator_merged_fn)
- e->type->ops.sq.elevator_merged_fn(q, rq, type);
+ if (e->type->ops.request_merged)
+ e->type->ops.request_merged(q, rq, type);
if (type == ELEVATOR_BACK_MERGE)
elv_rqhash_reposition(q, rq);
@@ -525,197 +407,20 @@
struct request *next)
{
struct elevator_queue *e = q->elevator;
- bool next_sorted = false;
- if (e->uses_mq && e->type->ops.mq.requests_merged)
- e->type->ops.mq.requests_merged(q, rq, next);
- else if (e->type->ops.sq.elevator_merge_req_fn) {
- next_sorted = (__force bool)(next->rq_flags & RQF_SORTED);
- if (next_sorted)
- e->type->ops.sq.elevator_merge_req_fn(q, rq, next);
- }
+ if (e->type->ops.requests_merged)
+ e->type->ops.requests_merged(q, rq, next);
elv_rqhash_reposition(q, rq);
-
- if (next_sorted) {
- elv_rqhash_del(q, next);
- q->nr_sorted--;
- }
-
q->last_merge = rq;
}
-
-void elv_bio_merged(struct request_queue *q, struct request *rq,
- struct bio *bio)
-{
- struct elevator_queue *e = q->elevator;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return;
-
- if (e->type->ops.sq.elevator_bio_merged_fn)
- e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio);
-}
-
-#ifdef CONFIG_PM
-static void blk_pm_requeue_request(struct request *rq)
-{
- if (rq->q->dev && !(rq->rq_flags & RQF_PM))
- rq->q->nr_pending--;
-}
-
-static void blk_pm_add_request(struct request_queue *q, struct request *rq)
-{
- if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 &&
- (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING))
- pm_request_resume(q->dev);
-}
-#else
-static inline void blk_pm_requeue_request(struct request *rq) {}
-static inline void blk_pm_add_request(struct request_queue *q,
- struct request *rq)
-{
-}
-#endif
-
-void elv_requeue_request(struct request_queue *q, struct request *rq)
-{
- /*
- * it already went through dequeue, we need to decrement the
- * in_flight count again
- */
- if (blk_account_rq(rq)) {
- q->in_flight[rq_is_sync(rq)]--;
- if (rq->rq_flags & RQF_SORTED)
- elv_deactivate_rq(q, rq);
- }
-
- rq->rq_flags &= ~RQF_STARTED;
-
- blk_pm_requeue_request(rq);
-
- __elv_add_request(q, rq, ELEVATOR_INSERT_REQUEUE);
-}
-
-void elv_drain_elevator(struct request_queue *q)
-{
- struct elevator_queue *e = q->elevator;
- static int printed;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return;
-
- lockdep_assert_held(q->queue_lock);
-
- while (e->type->ops.sq.elevator_dispatch_fn(q, 1))
- ;
- if (q->nr_sorted && !blk_queue_is_zoned(q) && printed++ < 10 ) {
- printk(KERN_ERR "%s: forced dispatching is broken "
- "(nr_sorted=%u), please report this\n",
- q->elevator->type->elevator_name, q->nr_sorted);
- }
-}
-
-void __elv_add_request(struct request_queue *q, struct request *rq, int where)
-{
- trace_block_rq_insert(q, rq);
-
- blk_pm_add_request(q, rq);
-
- rq->q = q;
-
- if (rq->rq_flags & RQF_SOFTBARRIER) {
- /* barriers are scheduling boundary, update end_sector */
- if (!blk_rq_is_passthrough(rq)) {
- q->end_sector = rq_end_sector(rq);
- q->boundary_rq = rq;
- }
- } else if (!(rq->rq_flags & RQF_ELVPRIV) &&
- (where == ELEVATOR_INSERT_SORT ||
- where == ELEVATOR_INSERT_SORT_MERGE))
- where = ELEVATOR_INSERT_BACK;
-
- switch (where) {
- case ELEVATOR_INSERT_REQUEUE:
- case ELEVATOR_INSERT_FRONT:
- rq->rq_flags |= RQF_SOFTBARRIER;
- list_add(&rq->queuelist, &q->queue_head);
- break;
-
- case ELEVATOR_INSERT_BACK:
- rq->rq_flags |= RQF_SOFTBARRIER;
- elv_drain_elevator(q);
- list_add_tail(&rq->queuelist, &q->queue_head);
- /*
- * We kick the queue here for the following reasons.
- * - The elevator might have returned NULL previously
- * to delay requests and returned them now. As the
- * queue wasn't empty before this request, ll_rw_blk
- * won't run the queue on return, resulting in hang.
- * - Usually, back inserted requests won't be merged
- * with anything. There's no point in delaying queue
- * processing.
- */
- __blk_run_queue(q);
- break;
-
- case ELEVATOR_INSERT_SORT_MERGE:
- /*
- * If we succeed in merging this request with one in the
- * queue already, we are done - rq has now been freed,
- * so no need to do anything further.
- */
- if (elv_attempt_insert_merge(q, rq))
- break;
- /* fall through */
- case ELEVATOR_INSERT_SORT:
- BUG_ON(blk_rq_is_passthrough(rq));
- rq->rq_flags |= RQF_SORTED;
- q->nr_sorted++;
- if (rq_mergeable(rq)) {
- elv_rqhash_add(q, rq);
- if (!q->last_merge)
- q->last_merge = rq;
- }
-
- /*
- * Some ioscheds (cfq) run q->request_fn directly, so
- * rq cannot be accessed after calling
- * elevator_add_req_fn.
- */
- q->elevator->type->ops.sq.elevator_add_req_fn(q, rq);
- break;
-
- case ELEVATOR_INSERT_FLUSH:
- rq->rq_flags |= RQF_SOFTBARRIER;
- blk_insert_flush(rq);
- break;
- default:
- printk(KERN_ERR "%s: bad insertion point %d\n",
- __func__, where);
- BUG();
- }
-}
-EXPORT_SYMBOL(__elv_add_request);
-
-void elv_add_request(struct request_queue *q, struct request *rq, int where)
-{
- unsigned long flags;
-
- spin_lock_irqsave(q->queue_lock, flags);
- __elv_add_request(q, rq, where);
- spin_unlock_irqrestore(q->queue_lock, flags);
-}
-EXPORT_SYMBOL(elv_add_request);
struct request *elv_latter_request(struct request_queue *q, struct request *rq)
{
struct elevator_queue *e = q->elevator;
- if (e->uses_mq && e->type->ops.mq.next_request)
- return e->type->ops.mq.next_request(q, rq);
- else if (!e->uses_mq && e->type->ops.sq.elevator_latter_req_fn)
- return e->type->ops.sq.elevator_latter_req_fn(q, rq);
+ if (e->type->ops.next_request)
+ return e->type->ops.next_request(q, rq);
return NULL;
}
@@ -724,66 +429,10 @@
{
struct elevator_queue *e = q->elevator;
- if (e->uses_mq && e->type->ops.mq.former_request)
- return e->type->ops.mq.former_request(q, rq);
- if (!e->uses_mq && e->type->ops.sq.elevator_former_req_fn)
- return e->type->ops.sq.elevator_former_req_fn(q, rq);
+ if (e->type->ops.former_request)
+ return e->type->ops.former_request(q, rq);
+
return NULL;
-}
-
-int elv_set_request(struct request_queue *q, struct request *rq,
- struct bio *bio, gfp_t gfp_mask)
-{
- struct elevator_queue *e = q->elevator;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return 0;
-
- if (e->type->ops.sq.elevator_set_req_fn)
- return e->type->ops.sq.elevator_set_req_fn(q, rq, bio, gfp_mask);
- return 0;
-}
-
-void elv_put_request(struct request_queue *q, struct request *rq)
-{
- struct elevator_queue *e = q->elevator;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return;
-
- if (e->type->ops.sq.elevator_put_req_fn)
- e->type->ops.sq.elevator_put_req_fn(rq);
-}
-
-int elv_may_queue(struct request_queue *q, unsigned int op)
-{
- struct elevator_queue *e = q->elevator;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return 0;
-
- if (e->type->ops.sq.elevator_may_queue_fn)
- return e->type->ops.sq.elevator_may_queue_fn(q, op);
-
- return ELV_MQUEUE_MAY;
-}
-
-void elv_completed_request(struct request_queue *q, struct request *rq)
-{
- struct elevator_queue *e = q->elevator;
-
- if (WARN_ON_ONCE(e->uses_mq))
- return;
-
- /*
- * request is released from the driver, io must be done
- */
- if (blk_account_rq(rq)) {
- q->in_flight[rq_is_sync(rq)]--;
- if ((rq->rq_flags & RQF_SORTED) &&
- e->type->ops.sq.elevator_completed_req_fn)
- e->type->ops.sq.elevator_completed_req_fn(q, rq);
- }
}
#define to_elv(atr) container_of((atr), struct elv_fs_entry, attr)
@@ -833,7 +482,7 @@
.release = elevator_release,
};
-int elv_register_queue(struct request_queue *q)
+int elv_register_queue(struct request_queue *q, bool uevent)
{
struct elevator_queue *e = q->elevator;
int error;
@@ -850,10 +499,10 @@
attr++;
}
}
- kobject_uevent(&e->kobj, KOBJ_ADD);
+ if (uevent)
+ kobject_uevent(&e->kobj, KOBJ_ADD);
+
e->registered = 1;
- if (!e->uses_mq && e->type->ops.sq.elevator_registered_fn)
- e->type->ops.sq.elevator_registered_fn(q);
}
return error;
}
@@ -867,14 +516,13 @@
kobject_uevent(&e->kobj, KOBJ_REMOVE);
kobject_del(&e->kobj);
+
e->registered = 0;
}
}
int elv_register(struct elevator_type *e)
{
- char *def = "";
-
/* create icq_cache if requested */
if (e->icq_size) {
if (WARN_ON(e->icq_size < sizeof(struct io_cq)) ||
@@ -891,7 +539,7 @@
/* register, don't allow duplicate names */
spin_lock(&elv_list_lock);
- if (elevator_find(e->elevator_name, e->uses_mq)) {
+ if (elevator_find(e->elevator_name, 0)) {
spin_unlock(&elv_list_lock);
kmem_cache_destroy(e->icq_cache);
return -EBUSY;
@@ -899,14 +547,8 @@
list_add_tail(&e->list, &elv_list);
spin_unlock(&elv_list_lock);
- /* print pretty message */
- if (elevator_match(e, chosen_elevator) ||
- (!*chosen_elevator &&
- elevator_match(e, CONFIG_DEFAULT_IOSCHED)))
- def = " (default)";
+ printk(KERN_INFO "io scheduler %s registered\n", e->elevator_name);
- printk(KERN_INFO "io scheduler %s registered%s\n", e->elevator_name,
- def);
return 0;
}
EXPORT_SYMBOL_GPL(elv_register);
@@ -940,6 +582,7 @@
if (q->elevator) {
if (q->elevator->registered)
elv_unregister_queue(q);
+
ioc_clear_queue(q);
elevator_exit(q, q->elevator);
}
@@ -949,7 +592,7 @@
goto out;
if (new_e) {
- ret = elv_register_queue(q);
+ ret = elv_register_queue(q, true);
if (ret) {
elevator_exit(q, q->elevator);
goto out;
@@ -965,33 +608,93 @@
return ret;
}
-/*
- * For blk-mq devices, we default to using mq-deadline, if available, for single
- * queue devices. If deadline isn't available OR we have multiple queues,
- * default to "none".
- */
-int elevator_init_mq(struct request_queue *q)
+static inline bool elv_support_iosched(struct request_queue *q)
{
- struct elevator_type *e;
- int err = 0;
+ if (!queue_is_mq(q) ||
+ (q->tag_set && (q->tag_set->flags & BLK_MQ_F_NO_SCHED)))
+ return false;
+ return true;
+}
+
+/*
+ * For single queue devices, default to using mq-deadline. If we have multiple
+ * queues or mq-deadline is not available, default to "none".
+ */
+static struct elevator_type *elevator_get_default(struct request_queue *q)
+{
+ if (q->tag_set && q->tag_set->flags & BLK_MQ_F_NO_SCHED_BY_DEFAULT)
+ return NULL;
if (q->nr_hw_queues != 1)
- return 0;
+ return NULL;
- WARN_ON_ONCE(test_bit(QUEUE_FLAG_REGISTERED, &q->queue_flags));
+ return elevator_get(q, "mq-deadline", false);
+}
+
+/*
+ * Get the first elevator providing the features required by the request queue.
+ * Default to "none" if no matching elevator is found.
+ */
+static struct elevator_type *elevator_get_by_features(struct request_queue *q)
+{
+ struct elevator_type *e, *found = NULL;
+
+ spin_lock(&elv_list_lock);
+
+ list_for_each_entry(e, &elv_list, list) {
+ if (elv_support_features(e->elevator_features,
+ q->required_elevator_features)) {
+ found = e;
+ break;
+ }
+ }
+
+ if (found && !try_module_get(found->elevator_owner))
+ found = NULL;
+
+ spin_unlock(&elv_list_lock);
+ return found;
+}
+
+/*
+ * For a device queue that has no required features, use the default elevator
+ * settings. Otherwise, use the first elevator available matching the required
+ * features. If no suitable elevator is find or if the chosen elevator
+ * initialization fails, fall back to the "none" elevator (no elevator).
+ */
+void elevator_init_mq(struct request_queue *q)
+{
+ struct elevator_type *e;
+ int err;
+
+ if (!elv_support_iosched(q))
+ return;
+
+ WARN_ON_ONCE(blk_queue_registered(q));
if (unlikely(q->elevator))
- goto out;
+ return;
- e = elevator_get(q, "mq-deadline", false);
+ if (!q->required_elevator_features)
+ e = elevator_get_default(q);
+ else
+ e = elevator_get_by_features(q);
if (!e)
- goto out;
+ return;
+
+ blk_mq_freeze_queue(q);
+ blk_mq_quiesce_queue(q);
err = blk_mq_init_sched(q, e);
- if (err)
+
+ blk_mq_unquiesce_queue(q);
+ blk_mq_unfreeze_queue(q);
+
+ if (err) {
+ pr_warn("\"%s\" elevator initialization failed, "
+ "falling back to \"none\"\n", e->elevator_name);
elevator_put(e);
-out:
- return err;
+ }
}
@@ -1003,71 +706,17 @@
*/
static int elevator_switch(struct request_queue *q, struct elevator_type *new_e)
{
- struct elevator_queue *old = q->elevator;
- bool old_registered = false;
int err;
lockdep_assert_held(&q->sysfs_lock);
- if (q->mq_ops) {
- blk_mq_freeze_queue(q);
- blk_mq_quiesce_queue(q);
+ blk_mq_freeze_queue(q);
+ blk_mq_quiesce_queue(q);
- err = elevator_switch_mq(q, new_e);
+ err = elevator_switch_mq(q, new_e);
- blk_mq_unquiesce_queue(q);
- blk_mq_unfreeze_queue(q);
-
- return err;
- }
-
- /*
- * Turn on BYPASS and drain all requests w/ elevator private data.
- * Block layer doesn't call into a quiesced elevator - all requests
- * are directly put on the dispatch list without elevator data
- * using INSERT_BACK. All requests have SOFTBARRIER set and no
- * merge happens either.
- */
- if (old) {
- old_registered = old->registered;
-
- blk_queue_bypass_start(q);
-
- /* unregister and clear all auxiliary data of the old elevator */
- if (old_registered)
- elv_unregister_queue(q);
-
- ioc_clear_queue(q);
- }
-
- /* allocate, init and register new elevator */
- err = new_e->ops.sq.elevator_init_fn(q, new_e);
- if (err)
- goto fail_init;
-
- err = elv_register_queue(q);
- if (err)
- goto fail_register;
-
- /* done, kill the old one and finish */
- if (old) {
- elevator_exit(q, old);
- blk_queue_bypass_end(q);
- }
-
- blk_add_trace_msg(q, "elv switch: %s", new_e->elevator_name);
-
- return 0;
-
-fail_register:
- elevator_exit(q, q->elevator);
-fail_init:
- /* switch failed, restore and re-register old elevator */
- if (old) {
- q->elevator = old;
- elv_register_queue(q);
- blk_queue_bypass_end(q);
- }
+ blk_mq_unquiesce_queue(q);
+ blk_mq_unfreeze_queue(q);
return err;
}
@@ -1087,15 +736,19 @@
/*
* Special case for mq, turn off scheduling
*/
- if (q->mq_ops && !strncmp(name, "none", 4))
+ if (!strncmp(name, "none", 4)) {
+ if (!q->elevator)
+ return 0;
return elevator_switch(q, NULL);
+ }
strlcpy(elevator_name, name, sizeof(elevator_name));
e = elevator_get(q, strstrip(elevator_name), true);
if (!e)
return -EINVAL;
- if (q->elevator && elevator_match(q->elevator->type, elevator_name)) {
+ if (q->elevator &&
+ elevator_match(q->elevator->type, elevator_name, 0)) {
elevator_put(e);
return 0;
}
@@ -1103,20 +756,12 @@
return elevator_switch(q, e);
}
-static inline bool elv_support_iosched(struct request_queue *q)
-{
- if (q->mq_ops && q->tag_set && (q->tag_set->flags &
- BLK_MQ_F_NO_SCHED))
- return false;
- return true;
-}
-
ssize_t elv_iosched_store(struct request_queue *q, const char *name,
size_t count)
{
int ret;
- if (!(q->mq_ops || q->request_fn) || !elv_support_iosched(q))
+ if (!elv_support_iosched(q))
return count;
ret = __elevator_change(q, name);
@@ -1131,10 +776,9 @@
struct elevator_queue *e = q->elevator;
struct elevator_type *elv = NULL;
struct elevator_type *__e;
- bool uses_mq = q->mq_ops != NULL;
int len = 0;
- if (!queue_is_rq_based(q))
+ if (!queue_is_mq(q))
return sprintf(name, "none\n");
if (!q->elevator)
@@ -1144,19 +788,18 @@
spin_lock(&elv_list_lock);
list_for_each_entry(__e, &elv_list, list) {
- if (elv && elevator_match(elv, __e->elevator_name) &&
- (__e->uses_mq == uses_mq)) {
+ if (elv && elevator_match(elv, __e->elevator_name, 0)) {
len += sprintf(name+len, "[%s] ", elv->elevator_name);
continue;
}
- if (__e->uses_mq && q->mq_ops && elv_support_iosched(q))
- len += sprintf(name+len, "%s ", __e->elevator_name);
- else if (!__e->uses_mq && !q->mq_ops)
+ if (elv_support_iosched(q) &&
+ elevator_match(__e, __e->elevator_name,
+ q->required_elevator_features))
len += sprintf(name+len, "%s ", __e->elevator_name);
}
spin_unlock(&elv_list_lock);
- if (q->mq_ops && q->elevator)
+ if (q->elevator)
len += sprintf(name+len, "none");
len += sprintf(len+name, "\n");
@@ -1186,3 +829,12 @@
return NULL;
}
EXPORT_SYMBOL(elv_rb_latter_request);
+
+static int __init elevator_setup(char *str)
+{
+ pr_warn("Kernel parameter elevator= does not have any effect anymore.\n"
+ "Please use sysfs to set IO scheduler for individual devices.\n");
+ return 1;
+}
+
+__setup("elevator=", elevator_setup);
--
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