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authorKeir Fraser <keir.fraser@citrix.com>2009-12-17 06:27:57 +0000
committerKeir Fraser <keir.fraser@citrix.com>2009-12-17 06:27:57 +0000
commit78c136415ecead2c856312c6bf13bd0086679c6e (patch)
treefe54f76dec62ae73c080a3a69bb784fa5573ff17 /tools/memshr/bidir-daemon.c
parent4515e6d82b23366933055b0ad60d8ed89f5a2b92 (diff)
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Maintains/cleans-up the sharing map. At the moment a simple FIFO policy is
applied. Signed-off-by: Grzegorz Milos <Grzegorz.Milos@citrix.com>
Diffstat (limited to 'tools/memshr/bidir-daemon.c')
-rw-r--r--tools/memshr/bidir-daemon.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/tools/memshr/bidir-daemon.c b/tools/memshr/bidir-daemon.c
new file mode 100644
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+++ b/tools/memshr/bidir-daemon.c
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+/******************************************************************************
+ *
+ * Copyright (c) 2009 Citrix (R&D) Inc. (Grzegorz Milos)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include <pthread.h>
+#include <inttypes.h>
+
+#include "bidir-hash.h"
+#include "memshr-priv.h"
+
+static struct blockshr_hash *blks_hash;
+
+void* bidir_daemon(void *unused)
+{
+ uint32_t nr_ent, max_nr_ent, tab_size, max_load, min_load;
+ static uint64_t shrhnd = 1;
+
+ while(1)
+ {
+ blockshr_hash_sizes( blks_hash,
+ &nr_ent,
+ &max_nr_ent,
+ &tab_size,
+ &max_load,
+ &min_load);
+ /* Remove some hints as soon as we get to 90% capacity */
+ if(10 * nr_ent > 9 * max_nr_ent)
+ {
+ uint64_t next_remove = shrhnd;
+ int to_remove;
+ int ret;
+
+ to_remove = 0.1 * max_nr_ent;
+ while(to_remove > 0)
+ {
+ ret = blockshr_shrhnd_remove(blks_hash, next_remove, NULL);
+ if(ret < 0)
+ {
+ /* We failed to remove an entry, because of a serious hash
+ * table error */
+ DPRINTF("Could not remove handle %"PRId64", error: %d\n",
+ next_remove, ret);
+ /* Force to exit the loop early */
+ to_remove = 0;
+ } else
+ if(ret > 0)
+ {
+ /* Managed to remove the entry. Note next_remove not
+ * incremented, in case there are duplicates */
+ shrhnd = next_remove;
+ to_remove--;
+ } else
+ {
+ /* Failed to remove, because there is no such handle */
+ next_remove++;
+ }
+ }
+ }
+
+ sleep(1);
+ }
+}
+
+void bidir_daemon_launch(void)
+{
+ pthread_t thread;
+
+ pthread_create(&thread, NULL, bidir_daemon, NULL);
+}
+
+void bidir_daemon_initialize(struct blockshr_hash *blks)
+{
+ blks_hash = blks;
+ bidir_daemon_launch();
+}