dm io tracker: factor out IO tracker

Allow other code to use dm_io_tracker.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index 6ab01ff..8e4ced5 100644 (file)
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -8,6 +8,7 @@
 #include "dm-bio-prison-v2.h"
 #include "dm-bio-record.h"
 #include "dm-cache-metadata.h"
+#include "dm-io-tracker.h"
 
 #include <linux/dm-io.h>
 #include <linux/dm-kcopyd.h>
@@ -39,77 +40,6 @@ DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(cache_copy_throttle,
 
 /*----------------------------------------------------------------*/
 
-struct io_tracker {
-       spinlock_t lock;
-
-       /*
-        * Sectors of in-flight IO.
-        */
-       sector_t in_flight;
-
-       /*
-        * The time, in jiffies, when this device became idle (if it is
-        * indeed idle).
-        */
-       unsigned long idle_time;
-       unsigned long last_update_time;
-};
-
-static void iot_init(struct io_tracker *iot)
-{
-       spin_lock_init(&iot->lock);
-       iot->in_flight = 0ul;
-       iot->idle_time = 0ul;
-       iot->last_update_time = jiffies;
-}
-
-static bool __iot_idle_for(struct io_tracker *iot, unsigned long jifs)
-{
-       if (iot->in_flight)
-               return false;
-
-       return time_after(jiffies, iot->idle_time + jifs);
-}
-
-static bool iot_idle_for(struct io_tracker *iot, unsigned long jifs)
-{
-       bool r;
-
-       spin_lock_irq(&iot->lock);
-       r = __iot_idle_for(iot, jifs);
-       spin_unlock_irq(&iot->lock);
-
-       return r;
-}
-
-static void iot_io_begin(struct io_tracker *iot, sector_t len)
-{
-       spin_lock_irq(&iot->lock);
-       iot->in_flight += len;
-       spin_unlock_irq(&iot->lock);
-}
-
-static void __iot_io_end(struct io_tracker *iot, sector_t len)
-{
-       if (!len)
-               return;
-
-       iot->in_flight -= len;
-       if (!iot->in_flight)
-               iot->idle_time = jiffies;
-}
-
-static void iot_io_end(struct io_tracker *iot, sector_t len)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&iot->lock, flags);
-       __iot_io_end(iot, len);
-       spin_unlock_irqrestore(&iot->lock, flags);
-}
-
-/*----------------------------------------------------------------*/
-
 /*
  * Represents a chunk of future work.  'input' allows continuations to pass
  * values between themselves, typically error values.
@@ -470,7 +400,7 @@ struct cache {
        struct batcher committer;
        struct work_struct commit_ws;
 
-       struct io_tracker tracker;
+       struct dm_io_tracker tracker;
 
        mempool_t migration_pool;
 
@@ -866,7 +796,7 @@ static void accounted_begin(struct cache *cache, struct bio *bio)
        if (accountable_bio(cache, bio)) {
                pb = get_per_bio_data(bio);
                pb->len = bio_sectors(bio);
-               iot_io_begin(&cache->tracker, pb->len);
+               dm_iot_io_begin(&cache->tracker, pb->len);
        }
 }
 
@@ -874,7 +804,7 @@ static void accounted_complete(struct cache *cache, struct bio *bio)
 {
        struct per_bio_data *pb = get_per_bio_data(bio);
 
-       iot_io_end(&cache->tracker, pb->len);
+       dm_iot_io_end(&cache->tracker, pb->len);
 }
 
 static void accounted_request(struct cache *cache, struct bio *bio)
@@ -1642,7 +1572,7 @@ enum busy {
 
 static enum busy spare_migration_bandwidth(struct cache *cache)
 {
-       bool idle = iot_idle_for(&cache->tracker, HZ);
+       bool idle = dm_iot_idle_for(&cache->tracker, HZ);
        sector_t current_volume = (atomic_read(&cache->nr_io_migrations) + 1) *
                cache->sectors_per_block;
 
@@ -2603,7 +2533,7 @@ static int cache_create(struct cache_args *ca, struct cache **result)
 
        batcher_init(&cache->committer, commit_op, cache,
                     issue_op, cache, cache->wq);
-       iot_init(&cache->tracker);
+       dm_iot_init(&cache->tracker);
 
        init_rwsem(&cache->background_work_lock);
        prevent_background_work(cache);

diff --git a/drivers/md/dm-io-tracker.h b/drivers/md/dm-io-tracker.h
new file mode 100644 (file)
index 0000000..1dcf01f
--- /dev/null
+++ b/drivers/md/dm-io-tracker.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2021 Red Hat, Inc. All rights reserved.
+ *
+ * This file is released under the GPL.
+ */
+
+#ifndef DM_IO_TRACKER_H
+#define DM_IO_TRACKER_H
+
+#include <linux/jiffies.h>
+
+struct dm_io_tracker {
+       spinlock_t lock;
+
+       /*
+        * Sectors of in-flight IO.
+        */
+       sector_t in_flight;
+
+       /*
+        * The time, in jiffies, when this device became idle
+        * (if it is indeed idle).
+        */
+       unsigned long idle_time;
+       unsigned long last_update_time;
+};
+
+static inline void dm_iot_init(struct dm_io_tracker *iot)
+{
+       spin_lock_init(&iot->lock);
+       iot->in_flight = 0ul;
+       iot->idle_time = 0ul;
+       iot->last_update_time = jiffies;
+}
+
+static inline bool dm_iot_idle_for(struct dm_io_tracker *iot, unsigned long j)
+{
+       bool r = false;
+
+       spin_lock_irq(&iot->lock);
+       if (!iot->in_flight)
+               r = time_after(jiffies, iot->idle_time + j);
+       spin_unlock_irq(&iot->lock);
+
+       return r;
+}
+
+static inline void dm_iot_io_begin(struct dm_io_tracker *iot, sector_t len)
+{
+       spin_lock_irq(&iot->lock);
+       iot->in_flight += len;
+       spin_unlock_irq(&iot->lock);
+}
+
+static inline void dm_iot_io_end(struct dm_io_tracker *iot, sector_t len)
+{
+       unsigned long flags;
+
+       if (!len)
+               return;
+
+       spin_lock_irqsave(&iot->lock, flags);
+       iot->in_flight -= len;
+       if (!iot->in_flight)
+               iot->idle_time = jiffies;
+       spin_unlock_irqrestore(&iot->lock, flags);
+}
+
+#endif