From: Zhi Yong Wu <wu...@linux.vnet.ibm.com>
Add a per-superblock workqueue and a work_struct
to run periodic work to update map info on each superblock.
Signed-off-by: Zhi Yong Wu <wu...@linux.vnet.ibm.com>
---
fs/hot_tracking.c | 94 ++++++++++++++++++++++++++++++++++++++++++
fs/hot_tracking.h | 3 +
include/linux/hot_tracking.h | 2 +
3 files changed, 99 insertions(+), 0 deletions(-)
diff --git a/fs/hot_tracking.c b/fs/hot_tracking.c
index a8dc599..f333c47 100644
--- a/fs/hot_tracking.c
+++ b/fs/hot_tracking.c
@@ -15,6 +15,8 @@
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/hardirq.h>
+#include <linux/kthread.h>
+#include <linux/freezer.h>
#include <linux/fs.h>
#include <linux/blkdev.h>
#include <linux/types.h>
@@ -623,6 +625,88 @@ static void hot_map_array_exit(struct hot_info *root)
}
/*
+ * Update temperatures for each hot inode item and
+ * hot range item for aging purposes
+ */
+static void hot_temperature_update_work(struct work_struct *work)
+{
+ struct hot_update_work *hot_work =
+ container_of(work, struct hot_update_work, work);
+ struct hot_info *root = hot_work->hot_info;
+ struct hot_inode_item *hi_nodes[8];
+ unsigned long delay = HZ * HEAT_UPDATE_DELAY;
+ u64 ino = 0;
+ int i, n;
+
+ do {
+ while (1) {
+ spin_lock(&root->lock);
+ n = radix_tree_gang_lookup(&root->hot_inode_tree,
+ (void **)hi_nodes, ino,
+ ARRAY_SIZE(hi_nodes));
+ if (!n) {
+ spin_unlock(&root->lock);
+ break;
+ }
+
+ ino = hi_nodes[n - 1]->i_ino + 1;
+ for (i = 0; i < n; i++) {
+ kref_get(&hi_nodes[i]->hot_inode.refs);
+ hot_map_array_update(
+ &hi_nodes[i]->hot_inode.hot_freq_data,
root);
+ hot_range_update(hi_nodes[i], root);
+ hot_inode_item_put(hi_nodes[i]);
+ }
+ spin_unlock(&root->lock);
+ }
+
+ if (unlikely(freezing(current))) {
+ __refrigerator(true);
+ } else {
+ set_current_state(TASK_INTERRUPTIBLE);
+ if (!kthread_should_stop()) {
+ schedule_timeout(delay);
+ }
+ __set_current_state(TASK_RUNNING);
+ }
+ } while (!kthread_should_stop());
+}
+
+static int hot_wq_init(struct hot_info *root)
+{
+ struct hot_update_work *hot_work;
+ int ret = 0;
+
+ root->update_wq = alloc_workqueue(
+ "hot_temperature_update", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
+ if (!root->update_wq) {
+ printk(KERN_ERR "%s: failed to create "
+ "temperature update workqueue\n",
+ __func__);
+ return 1;
+ }
+
+ hot_work = kmalloc(sizeof(*hot_work), GFP_NOFS);
+ if (hot_work) {
+ hot_work->hot_info = root;
+ INIT_WORK(&hot_work->work, hot_temperature_update_work);
+ queue_work(root->update_wq, &hot_work->work);
+ } else {
+ printk(KERN_ERR "%s: failed to create update work\n",
+ __func__);
+ ret = 1;
+ }
+
+ return ret;
+}
+
+static void hot_wq_exit(struct workqueue_struct *wq)
+{
+ flush_workqueue(wq);
+ destroy_workqueue(wq);
+}
+
+/*
* Initialize kmem cache for hot_inode_item and hot_range_item.
*/
static int __init hot_cache_init(void)
@@ -686,10 +770,19 @@ void hot_track_init(struct super_block *sb)
hot_inode_tree_init(root);
hot_map_array_init(root);
+ err = hot_wq_init(root);
+ if (err)
+ goto failed_wq;
+
printk(KERN_INFO "vfs: turning on hot data tracking\n");
return;
+failed_wq:
+ hot_map_array_exit(root);
+ hot_inode_tree_exit(root);
+ sb->hot_flags &= ~MS_HOT_TRACKING;
+ kfree(root);
failed_root:
hot_cache_exit();
}
@@ -698,6 +791,7 @@ void hot_track_exit(struct super_block *sb)
{
struct hot_info *root = global_hot_tracking_info;
+ hot_wq_exit(root->update_wq);
hot_map_array_exit(root);
hot_inode_tree_exit(root);
sb->hot_flags &= ~MS_HOT_TRACKING;
diff --git a/fs/hot_tracking.h b/fs/hot_tracking.h
index d19e64a..7a79a6d 100644
--- a/fs/hot_tracking.h
+++ b/fs/hot_tracking.h
@@ -36,6 +36,9 @@
*/
#define TIME_TO_KICK 400
+/* set how often to update temperatures (seconds) */
+#define HEAT_UPDATE_DELAY 400
+
/*
* The following comments explain what exactly comprises a unit of heat.
*
diff --git a/include/linux/hot_tracking.h b/include/linux/hot_tracking.h
index 7114179..b37e0f8 100644
--- a/include/linux/hot_tracking.h
+++ b/include/linux/hot_tracking.h
@@ -84,6 +84,8 @@ struct hot_info {
/* map of range temperature */
struct hot_map_head heat_range_map[HEAT_MAP_SIZE];
+
+ struct workqueue_struct *update_wq;
};
extern struct hot_info *global_hot_tracking_info;
--
1.7.6.5
--
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