features/bitrot: Move throttling code to libglusterfs

Backport of  http://review.gluster.org/14846

Since throttling is a separate feature by itself,
move throttling code to libglusterfs.

Change-Id: If9b99885ceb46e5b1865a4af18b2a2caecf59972
BUG: 1357514
Signed-off-by: Kotresh HR <khiremat@redhat.com>
Reviewed-on: http://review.gluster.org/14944
Smoke: Gluster Build System <jenkins@build.gluster.org>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Jeff Darcy <jdarcy@redhat.com>

1 files changed, 74 insertions, 0 deletions

diff --git a/libglusterfs/src/throttle-tbf.h b/libglusterfs/src/throttle-tbf.h
new file mode 100644
index 00000000000..b6e04962ca4
--- /dev/null
+++ b/libglusterfs/src/throttle-tbf.h
@@ -0,0 +1,74 @@
+/*
+   Copyright (c) 2015 Red Hat, Inc. <http://www.redhat.com>
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+
+#include "list.h"
+#include "xlator.h"
+#include "locking.h"
+
+#ifndef THROTTLE_TBF_H__
+#define THROTTLE_TBF_H__
+
+typedef enum tbf_ops {
+        TBF_OP_MIN     = -1,
+        TBF_OP_HASH    = 0,    /* checksum calculation  */
+        TBF_OP_READ    = 1,    /* inode read(s)         */
+        TBF_OP_READDIR = 2,    /* dentry read(s)        */
+        TBF_OP_MAX     = 3,
+} tbf_ops_t;
+
+/**
+ * Operation rate specification
+ */
+typedef struct tbf_opspec {
+        tbf_ops_t op;
+
+        unsigned long rate;
+
+        unsigned long maxlimit;
+
+        unsigned long token_gen_interval;/* Token generation interval in usec */
+} tbf_opspec_t;
+
+/**
+ * Token bucket for each operation type
+ */
+typedef struct tbf_bucket {
+        gf_lock_t lock;
+
+        pthread_t tokener;         /* token generator thread          */
+
+        unsigned long tokenrate;   /* token generation rate           */
+
+        unsigned long tokens;      /* number of current tokens        */
+
+        unsigned long maxtokens;   /* maximum token in the bucket     */
+
+        struct list_head queued;   /* list of non-conformant requests */
+
+        unsigned long token_gen_interval;/* Token generation interval in usec */
+} tbf_bucket_t;
+
+typedef struct tbf {
+        tbf_bucket_t **bucket;
+} tbf_t;
+
+tbf_t *
+tbf_init (tbf_opspec_t *, unsigned int);
+
+int
+tbf_mod (tbf_t *, tbf_opspec_t *);
+
+void
+tbf_throttle (tbf_t *, tbf_ops_t, unsigned long);
+
+#define TBF_THROTTLE_BEGIN(tbf, op, tokens) (tbf_throttle (tbf, op, tokens))
+#define TBF_THROTTLE_END(tbf, op, tokens)
+
+#endif /** THROTTLE_TBF_H__ */