From 01dcc756aa82ad535d349b40cc1d639734b5f7ca Mon Sep 17 00:00:00 2001
From: Pranith Kumar K <pkarampu@redhat.com>
Date: Fri, 17 Nov 2017 07:12:42 +0530
Subject: [PATCH 235/236] cluster-syncop: Implement tiebreaker inodelk/entrylk
In this implementation, inodelk/entrylk will be tried for the subvols
given with trylock. In this attempt if all locks are obtained, then
inodelk is successful, otherwise, if it gets success on the first
available subvolume, then it will go for blocking lock, where as other
subvolumes will not try and this acts as tie-breaker.
>Updates gluster/glusterfs#354
Upstream-patch: https://review.gluster.org/18819
BUG: 1562744
Change-Id: Ia2521b9ccb81a42bd6104ab21f610f761ba2b801
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>
Reviewed-on: https://code.engineering.redhat.com/gerrit/134278
Tested-by: RHGS Build Bot <nigelb@redhat.com>
Reviewed-by: Ashish Pandey <aspandey@redhat.com>
---
libglusterfs/src/cluster-syncop.c | 96 +++++++++++++++++++++++++++++++++++++++
libglusterfs/src/cluster-syncop.h | 7 +++
2 files changed, 103 insertions(+)
diff --git a/libglusterfs/src/cluster-syncop.c b/libglusterfs/src/cluster-syncop.c
index b7f4dfe..75ba640 100644
--- a/libglusterfs/src/cluster-syncop.c
+++ b/libglusterfs/src/cluster-syncop.c
@@ -1191,3 +1191,99 @@ cluster_entrylk (xlator_t **subvols, unsigned char *on, int numsubvols,
loc_wipe (&loc);
return cluster_fop_success_fill (replies, numsubvols, locked_on);
}
+
+int
+cluster_tiebreaker_inodelk (xlator_t **subvols, unsigned char *on,
+ int numsubvols, default_args_cbk_t *replies,
+ unsigned char *locked_on, call_frame_t *frame,
+ xlator_t *this, char *dom, inode_t *inode,
+ off_t off, size_t size)
+{
+ struct gf_flock flock = {0, };
+ int i = 0;
+ int num_success = 0;
+ loc_t loc = {0};
+ unsigned char *output = NULL;
+
+ flock.l_type = F_WRLCK;
+ flock.l_start = off;
+ flock.l_len = size;
+
+ output = alloca(numsubvols);
+ loc.inode = inode_ref (inode);
+ gf_uuid_copy (loc.gfid, inode->gfid);
+ FOP_ONLIST (subvols, on, numsubvols, replies, locked_on, frame,
+ inodelk, dom, &loc, F_SETLK, &flock, NULL);
+
+ for (i = 0; i < numsubvols; i++) {
+ if (replies[i].valid && replies[i].op_ret == 0) {
+ num_success++;
+ continue;
+ }
+ if (replies[i].op_ret == -1 && replies[i].op_errno == EAGAIN) {
+ cluster_fop_success_fill (replies, numsubvols,
+ locked_on);
+ cluster_uninodelk (subvols, locked_on, numsubvols,
+ replies, output, frame, this, dom,
+ inode, off, size);
+
+ if (num_success) {
+ FOP_SEQ (subvols, on, numsubvols, replies,
+ locked_on, frame, inodelk, dom, &loc,
+ F_SETLKW, &flock, NULL);
+ } else {
+ memset (locked_on, 0, numsubvols);
+ }
+ break;
+ }
+ }
+
+ loc_wipe (&loc);
+ return cluster_fop_success_fill (replies, numsubvols, locked_on);
+}
+
+int
+cluster_tiebreaker_entrylk (xlator_t **subvols, unsigned char *on,
+ int numsubvols, default_args_cbk_t *replies,
+ unsigned char *locked_on, call_frame_t *frame,
+ xlator_t *this, char *dom, inode_t *inode,
+ const char *name)
+{
+ int i = 0;
+ loc_t loc = {0};
+ unsigned char *output = NULL;
+ int num_success = 0;
+
+ output = alloca(numsubvols);
+ loc.inode = inode_ref (inode);
+ gf_uuid_copy (loc.gfid, inode->gfid);
+ FOP_ONLIST (subvols, on, numsubvols, replies, locked_on, frame,
+ entrylk, dom, &loc, name, ENTRYLK_LOCK_NB, ENTRYLK_WRLCK,
+ NULL);
+
+ for (i = 0; i < numsubvols; i++) {
+ if (replies[i].valid && replies[i].op_ret == 0) {
+ num_success++;
+ continue;
+ }
+ if (replies[i].op_ret == -1 && replies[i].op_errno == EAGAIN) {
+ cluster_fop_success_fill (replies, numsubvols,
+ locked_on);
+ cluster_unentrylk (subvols, locked_on, numsubvols,
+ replies, output, frame, this, dom,
+ inode, name);
+ if (num_success) {
+ FOP_SEQ (subvols, on, numsubvols, replies,
+ locked_on, frame, entrylk, dom, &loc,
+ name, ENTRYLK_LOCK, ENTRYLK_WRLCK,
+ NULL);
+ } else {
+ memset (locked_on, 0, numsubvols);
+ }
+ break;
+ }
+ }
+
+ loc_wipe (&loc);
+ return cluster_fop_success_fill (replies, numsubvols, locked_on);
+}
diff --git a/libglusterfs/src/cluster-syncop.h b/libglusterfs/src/cluster-syncop.h
index ff9387a..b91a09e 100644
--- a/libglusterfs/src/cluster-syncop.h
+++ b/libglusterfs/src/cluster-syncop.h
@@ -209,4 +209,11 @@ int32_t
cluster_xattrop_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
int32_t op_ret, int32_t op_errno, dict_t *dict,
dict_t *xdata);
+
+int
+cluster_tiebreaker_inodelk (xlator_t **subvols, unsigned char *on,
+ int numsubvols, default_args_cbk_t *replies,
+ unsigned char *locked_on, call_frame_t *frame,
+ xlator_t *this, char *dom, inode_t *inode,
+ off_t off, size_t size);
#endif /* !_CLUSTER_SYNCOP_H */
--
1.8.3.1