MINOR: backend: replace the lbprm lock with an rwlock
It was previously a spinlock, and it happens that a number of LB algos
only lock it for lookups, without performing any modification. Let's
first turn it to an rwlock and w-lock it everywhere. This is strictly
identical.
It was carefully checked that every HA_SPIN_LOCK() was turned to
HA_RWLOCK_WRLOCK() and that HA_SPIN_UNLOCK() was turned to
HA_RWLOCK_WRUNLOCK() on this lock. _INIT and _DESTROY were updated too.
diff --git a/include/haproxy/backend-t.h b/include/haproxy/backend-t.h
index daaf386..bb8ec6f 100644
--- a/include/haproxy/backend-t.h
+++ b/include/haproxy/backend-t.h
@@ -157,7 +157,7 @@
int arg_opt2; /* extra option 2 for the LB algo (algo-specific) */
int arg_opt3; /* extra option 3 for the LB algo (algo-specific) */
struct server *fbck; /* first backup server when !PR_O_USE_ALL_BK, or NULL */
- __decl_thread(HA_SPINLOCK_T lock);
+ __decl_thread(HA_RWLOCK_T lock);
/* Call backs for some actions. Any of them may be NULL (thus should be ignored). */
void (*update_server_eweight)(struct server *); /* to be called after eweight change */
diff --git a/src/cfgparse.c b/src/cfgparse.c
index cda2590..4d3c8ad 100644
--- a/src/cfgparse.c
+++ b/src/cfgparse.c
@@ -3270,7 +3270,7 @@
}
break;
}
- HA_SPIN_INIT(&curproxy->lbprm.lock);
+ HA_RWLOCK_INIT(&curproxy->lbprm.lock);
if (curproxy->options & PR_O_LOGASAP)
curproxy->to_log &= ~LW_BYTES;
diff --git a/src/haproxy.c b/src/haproxy.c
index 83e57ce..389abb8 100644
--- a/src/haproxy.c
+++ b/src/haproxy.c
@@ -2685,7 +2685,7 @@
p0 = p;
p = p->next;
- HA_SPIN_DESTROY(&p0->lbprm.lock);
+ HA_RWLOCK_DESTROY(&p0->lbprm.lock);
HA_SPIN_DESTROY(&p0->lock);
free(p0);
}/* end while(p) */
diff --git a/src/lb_chash.c b/src/lb_chash.c
index 55417b5..a37a40f 100644
--- a/src/lb_chash.c
+++ b/src/lb_chash.c
@@ -124,7 +124,7 @@
if (!srv_lb_status_changed(srv))
return;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv_willbe_usable(srv))
goto out_update_state;
@@ -162,7 +162,7 @@
out_update_state:
srv_lb_commit_status(srv);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
}
/* This function updates the server trees according to server <srv>'s new
@@ -181,7 +181,7 @@
if (!srv_lb_status_changed(srv))
return;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (!srv_willbe_usable(srv))
goto out_update_state;
@@ -224,7 +224,7 @@
out_update_state:
srv_lb_commit_status(srv);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
}
/* This function must be called after an update to server <srv>'s effective
@@ -264,7 +264,7 @@
return;
}
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
/* only adjust the server's presence in the tree */
chash_queue_dequeue_srv(srv);
@@ -277,7 +277,7 @@
update_backend_weight(p);
srv_lb_commit_status(srv);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
}
/*
@@ -324,7 +324,7 @@
unsigned int dn, dp;
int loop;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (p->srv_act)
root = &p->lbprm.chash.act;
@@ -379,7 +379,7 @@
}
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
return nsrv;
}
@@ -395,7 +395,7 @@
srv = avoided = NULL;
avoided_node = NULL;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (p->srv_act)
root = &p->lbprm.chash.act;
else if (p->lbprm.fbck) {
@@ -454,7 +454,7 @@
}
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
return srv;
}
diff --git a/src/lb_fas.c b/src/lb_fas.c
index 0fcd5e3..43ff6a5 100644
--- a/src/lb_fas.c
+++ b/src/lb_fas.c
@@ -65,12 +65,12 @@
*/
static void fas_srv_reposition(struct server *s)
{
- HA_SPIN_LOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
if (s->lb_tree) {
fas_dequeue_srv(s);
fas_queue_srv(s);
}
- HA_SPIN_UNLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
}
/* This function updates the server trees according to server <srv>'s new
@@ -91,7 +91,7 @@
if (srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (!srv_currently_usable(srv))
/* server was already down */
@@ -124,7 +124,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -149,7 +149,7 @@
if (!srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv_currently_usable(srv))
/* server was already up */
@@ -188,7 +188,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -231,7 +231,7 @@
return;
}
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv->lb_tree)
fas_dequeue_srv(srv);
@@ -247,7 +247,7 @@
fas_queue_srv(srv);
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
srv_lb_commit_status(srv);
}
@@ -300,7 +300,7 @@
srv = avoided = NULL;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (p->srv_act)
node = eb32_first(&p->lbprm.fas.act);
else if (p->lbprm.fbck) {
@@ -336,7 +336,7 @@
if (!srv)
srv = avoided;
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
return srv;
}
diff --git a/src/lb_fwlc.c b/src/lb_fwlc.c
index 8eac2c9..882dd7d 100644
--- a/src/lb_fwlc.c
+++ b/src/lb_fwlc.c
@@ -63,12 +63,12 @@
*/
static void fwlc_srv_reposition(struct server *s)
{
- HA_SPIN_LOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
if (s->lb_tree) {
fwlc_dequeue_srv(s);
fwlc_queue_srv(s);
}
- HA_SPIN_UNLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &s->proxy->lbprm.lock);
}
/* This function updates the server trees according to server <srv>'s new
@@ -88,7 +88,7 @@
if (srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (!srv_currently_usable(srv))
@@ -122,7 +122,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -147,7 +147,7 @@
if (!srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv_currently_usable(srv))
/* server was already up */
@@ -186,7 +186,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -229,7 +229,7 @@
return;
}
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv->lb_tree)
fwlc_dequeue_srv(srv);
@@ -245,7 +245,7 @@
fwlc_queue_srv(srv);
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
srv_lb_commit_status(srv);
}
@@ -298,7 +298,7 @@
srv = avoided = NULL;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (p->srv_act)
node = eb32_first(&p->lbprm.fwlc.act);
else if (p->lbprm.fbck) {
@@ -334,7 +334,7 @@
if (!srv)
srv = avoided;
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
return srv;
}
diff --git a/src/lb_fwrr.c b/src/lb_fwrr.c
index 05ae5f6..e2cdd9f 100644
--- a/src/lb_fwrr.c
+++ b/src/lb_fwrr.c
@@ -43,7 +43,7 @@
if (srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (!srv_currently_usable(srv))
/* server was already down */
@@ -79,7 +79,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -105,7 +105,7 @@
if (!srv_willbe_usable(srv))
goto out_update_state;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (srv_currently_usable(srv))
/* server was already up */
@@ -147,7 +147,7 @@
out_update_backend:
/* check/update tot_used, tot_weight */
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
@@ -191,7 +191,7 @@
return;
}
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
grp = (srv->flags & SRV_F_BACKUP) ? &p->lbprm.fwrr.bck : &p->lbprm.fwrr.act;
grp->next_weight = grp->next_weight - srv->cur_eweight + srv->next_eweight;
@@ -239,7 +239,7 @@
}
update_backend_weight(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
srv_lb_commit_status(srv);
}
@@ -514,7 +514,7 @@
struct fwrr_group *grp;
int switched;
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
if (p->srv_act)
grp = &p->lbprm.fwrr.act;
else if (p->lbprm.fbck) {
@@ -611,7 +611,7 @@
}
}
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
return srv;
}
diff --git a/src/lb_map.c b/src/lb_map.c
index ef32deb..1432913 100644
--- a/src/lb_map.c
+++ b/src/lb_map.c
@@ -32,11 +32,11 @@
goto out_update_state;
/* FIXME: could be optimized since we know what changed */
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
recount_servers(p);
update_backend_weight(p);
recalc_server_map(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
}
@@ -56,11 +56,11 @@
goto out_update_state;
/* FIXME: could be optimized since we know what changed */
- HA_SPIN_LOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &p->lbprm.lock);
recount_servers(p);
update_backend_weight(p);
recalc_server_map(p);
- HA_SPIN_UNLOCK(LBPRM_LOCK, &p->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &p->lbprm.lock);
out_update_state:
srv_lb_commit_status(srv);
}
@@ -216,7 +216,7 @@
int newidx, avoididx;
struct server *srv, *avoided;
- HA_SPIN_LOCK(LBPRM_LOCK, &px->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &px->lbprm.lock);
if (px->lbprm.tot_weight == 0) {
avoided = NULL;
goto out;
@@ -248,7 +248,7 @@
px->lbprm.map.rr_idx = avoididx;
out:
- HA_SPIN_UNLOCK(LBPRM_LOCK, &px->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &px->lbprm.lock);
/* return NULL or srvtoavoid if found */
return avoided;
}
@@ -265,10 +265,10 @@
{
struct server *srv = NULL;
- HA_SPIN_LOCK(LBPRM_LOCK, &px->lbprm.lock);
+ HA_RWLOCK_WRLOCK(LBPRM_LOCK, &px->lbprm.lock);
if (px->lbprm.tot_weight)
srv = px->lbprm.map.srv[hash % px->lbprm.tot_weight];
- HA_SPIN_UNLOCK(LBPRM_LOCK, &px->lbprm.lock);
+ HA_RWLOCK_WRUNLOCK(LBPRM_LOCK, &px->lbprm.lock);
return srv;
}