From cc6e431b13f8c2b852e8a9184c0da339f7461fe9 Mon Sep 17 00:00:00 2001
From: Con Kolivas <kernel@kolivas.org>
Date: Fri, 23 Sep 2016 13:04:19 +1000
Subject: [PATCH] Properly handle userproxy priorities

---
 src/stratifier.c | 55 +++++++++++++++++++++++++++++-------------------
 1 file changed, 33 insertions(+), 22 deletions(-)

diff --git a/src/stratifier.c b/src/stratifier.c
index 304a5928..1d8592fe 100644
--- a/src/stratifier.c
+++ b/src/stratifier.c
@@ -2081,19 +2081,25 @@ static int64_t prio_sort(proxy_t *a, proxy_t *b)
 	return (a->priority - b->priority);
 }
 
+/* Masked increment */
+static int64_t masked_inc(int64_t value, int64_t mask)
+{
+	value &= ~mask;
+	value++;
+	value |= mask;
+	return value;
+}
+
 /* Priority values can be sparse, they do not need to be sequential */
 static void __set_proxy_prio(sdata_t *sdata, proxy_t *proxy, int64_t priority)
 {
 	proxy_t *tmpa, *tmpb, *exists = NULL;
-	int64_t next_prio = 0;
+	int64_t mask, next_prio = 0;
 
 	/* Encode the userid as the high bits in priority */
-	if (!proxy->global) {
-		int64_t high_bits = proxy->userid;
-
-		high_bits <<= 32;
-		priority |= high_bits;
-	}
+	mask = proxy->userid;
+	mask <<= 32;
+	priority |= mask;
 
 	/* See if the priority is already in use */
 	HASH_ITER(hh, sdata->proxies, tmpa, tmpb) {
@@ -2101,7 +2107,7 @@ static void __set_proxy_prio(sdata_t *sdata, proxy_t *proxy, int64_t priority)
 			break;
 		if (tmpa->priority == priority) {
 			exists = tmpa;
-			next_prio = exists->priority + 1;
+			next_prio = masked_inc(priority, mask);
 			break;
 		}
 	}
@@ -2109,7 +2115,7 @@ static void __set_proxy_prio(sdata_t *sdata, proxy_t *proxy, int64_t priority)
 	HASH_ITER(hh, exists, tmpa, tmpb) {
 		if (tmpa->priority > next_prio)
 			break;
-		tmpa->priority++;
+		tmpa->priority = masked_inc(tmpa->priority, mask);
 		next_prio++;
 	}
 	proxy->priority = priority;
@@ -2225,11 +2231,15 @@ static proxy_t *existing_subproxy(sdata_t *sdata, const int id, const int subid)
 	return subproxy;
 }
 
+static void check_userproxies(sdata_t *sdata, proxy_t *proxy, const int userid);
+
 static void set_proxy_prio(sdata_t *sdata, proxy_t *proxy, const int priority)
 {
 	mutex_lock(&sdata->proxy_lock);
 	__set_proxy_prio(sdata, proxy, priority);
 	mutex_unlock(&sdata->proxy_lock);
+
+	check_userproxies(sdata, proxy, proxy->userid);
 }
 
 /* Set proxy to the current proxy and calculate how much headroom it has */
@@ -2544,7 +2554,7 @@ static void recruit_best_userproxy(sdata_t *sdata, const int userid, const int r
 
 /* Check how much headroom the userid proxies have and reconnect any clients
  * that are not bound to it that should be */
-static void check_userproxies(sdata_t *sdata, const int userid)
+static void check_userproxies(sdata_t *sdata, proxy_t *proxy, const int userid)
 {
 	int64_t headroom = proxy_headroom(sdata, userid);
 	stratum_instance_t *client, *tmpclient;
@@ -2558,8 +2568,10 @@ static void check_userproxies(sdata_t *sdata, const int userid)
 			continue;
 		if (client->user_id != userid)
 			continue;
-		/* Is this client bound to a dead proxy? */
-		if (!client->reconnect && client->proxy->userid == userid)
+		/* Is the client already bound to a proxy of its own userid of
+		 * a higher priority than this one. */
+		if (client->proxy->userid == userid &&
+		    client->proxy->parent->priority <= proxy->parent->priority)
 			continue;
 		if (headroom-- < 1)
 			continue;
@@ -2681,7 +2693,7 @@ static void update_notify(ckpool_t *ckp, const char *cmd)
 		if (proxy->parent != best_proxy(sdata)->parent)
 			reconnect_clients(sdata);
 	} else
-		check_userproxies(sdata, proxy->userid);
+		check_userproxies(sdata, proxy, proxy->userid);
 	clean |= new_block;
 	LOGINFO("Proxy %d:%d broadcast updated stratum notify with%s clean", id,
 		subid, clean ? "" : "out");
@@ -4355,19 +4367,16 @@ static proxy_t *__best_subproxy(proxy_t *proxy)
  * running out of room. */
 static sdata_t *select_sdata(const ckpool_t *ckp, sdata_t *ckp_sdata, const int userid)
 {
-	proxy_t *current, *proxy, *tmp, *best = NULL;
+	proxy_t *global, *proxy, *tmp, *best = NULL;
 
 	if (!ckp->proxy || ckp->passthrough)
 		return ckp_sdata;
-	current = ckp_sdata->proxy;
-	if (!current) {
-		LOGWARNING("No proxy available yet to generate subscribes");
-		return NULL;
-	}
 
 	/* Proxies are ordered by priority so first available will be the best
 	 * priority */
 	mutex_lock(&ckp_sdata->proxy_lock);
+	best = global = ckp_sdata->proxy;
+
 	HASH_ITER(hh, ckp_sdata->proxies, proxy, tmp) {
 		if (proxy->userid < userid)
 			continue;
@@ -4381,12 +4390,14 @@ static sdata_t *select_sdata(const ckpool_t *ckp, sdata_t *ckp_sdata, const int
 
 	if (!best) {
 		if (!userid)
-			LOGWARNING("Temporarily insufficient subproxies to accept more clients");
+			LOGWARNING("Temporarily insufficient proxies to accept more clients");
+		else
+			LOGNOTICE("Temporarily insufficient proxies for userid %d to accept more clients", userid);
 		return NULL;
 	}
 	if (!userid) {
-		if (best->id != current->id || current_headroom(ckp_sdata, &proxy) < 2)
-			generator_recruit(ckp, current->id, 1);
+		if (best->id != global->id || current_headroom(ckp_sdata, &proxy) < 2)
+			generator_recruit(ckp, global->id, 1);
 	} else {
 		if (proxy_headroom(ckp_sdata, userid) < 2)
 			generator_recruit(ckp, best->id, 1);