lkml.org 
[lkml]   [2012]   [Oct]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[RFC v3 08/13] vfs: add aging function for old map info
Date
From: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>

Signed-off-by: Zhi Yong Wu <wuzhy@linux.vnet.ibm.com>
---
fs/hot_tracking.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/hot_tracking.h | 6 +++++
2 files changed, 63 insertions(+), 0 deletions(-)

diff --git a/fs/hot_tracking.c b/fs/hot_tracking.c
index 717faa7..a8dc599 100644
--- a/fs/hot_tracking.c
+++ b/fs/hot_tracking.c
@@ -376,6 +376,24 @@ inline void hot_update_freqs(struct hot_info *root,
hot_inode_item_put(he);
}

+static bool hot_freq_data_is_aging(struct hot_freq_data *freq_data)
+{
+ int ret = 0;
+ struct timespec ckt = current_kernel_time();
+
+ u64 cur_time = timespec_to_ns(&ckt);
+ u64 last_read_ns =
+ (cur_time - timespec_to_ns(&freq_data->last_read_time));
+ u64 last_write_ns =
+ (cur_time - timespec_to_ns(&freq_data->last_write_time));
+ u64 kick_ns = TIME_TO_KICK * (u64)1000000000;
+
+ if ((last_read_ns > kick_ns) && (last_write_ns > kick_ns))
+ ret = 1;
+
+ return ret;
+}
+
static u64 hot_raw_shift(u64 counter, u32 bits, bool dir)
{
if (dir)
@@ -529,6 +547,45 @@ static void hot_map_array_update(struct hot_freq_data *freq_data,
}
}

+/* Update temperatures for each range item for aging purposes */
+static void hot_range_update(struct hot_inode_item *he,
+ struct hot_info *root)
+{
+ struct hot_range_item *hr_nodes[8];
+ u32 start = 0;
+ bool range_is_aging;
+ int i, n;
+
+ while (1) {
+ spin_lock(&he->lock);
+ n = radix_tree_gang_lookup(&he->hot_range_tree,
+ (void **)hr_nodes, start,
+ ARRAY_SIZE(hr_nodes));
+ if (!n) {
+ spin_unlock(&he->lock);
+ break;
+ }
+
+ start = hr_nodes[n - 1]->start + 1;
+ for (i = 0; i < n; i++) {
+ kref_get(&hr_nodes[i]->hot_range.refs);
+ hot_map_array_update(
+ &hr_nodes[i]->hot_range.hot_freq_data, root);
+
+ spin_lock(&hr_nodes[i]->hot_range.lock);
+ range_is_aging = hot_freq_data_is_aging(
+ &hr_nodes[i]->hot_range.hot_freq_data);
+ spin_unlock(&hr_nodes[i]->hot_range.lock);
+
+ hot_range_item_put(hr_nodes[i]);
+ if (range_is_aging) {
+ hot_range_item_put(hr_nodes[i]);
+ }
+ }
+ spin_unlock(&he->lock);
+ }
+}
+
/*
* Initialize inode and range map arrays.
*/
diff --git a/fs/hot_tracking.h b/fs/hot_tracking.h
index 5a9517b..d19e64a 100644
--- a/fs/hot_tracking.h
+++ b/fs/hot_tracking.h
@@ -31,6 +31,12 @@
#define FREQ_POWER 4

/*
+ * time to quit keeping track of
+ * tracking data (seconds)
+ */
+#define TIME_TO_KICK 400
+
+/*
* The following comments explain what exactly comprises a unit of heat.
*
* Each of six values of heat are calculated and combined in order to form an
--
1.7.6.5


\
 
 \ /
  Last update: 2012-10-10 13:21    [W:0.383 / U:0.272 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site