Fold in some stuff to allow for matching of workers

to their actual scoreboard slots, independent of slot
ID.


git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@984188 13f79535-47bb-0310-9956-ffa450edef68

include/ap_mmn.h

@@ -241,6 +241,8 @@
  * 20100719.0 (2.3.7-dev)  Add symbol name parameter to ap_add_module and
  *                         ap_add_loaded_module. Add ap_find_module_short_name
  * 20100723.0 (2.3.7-dev)  Remove ct_output_filters from core rec
+ * 20100723.1 (2.3.7-dev)  Added ap_proxy_hashfunc() and hash elements to
+ *                         proxy worker structs
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503234UL /* "AP24" */

modules/proxy/mod_proxy.h

@@ -251,11 +251,13 @@ struct proxy_conn_pool {
 /* worker status flags */
 #define PROXY_WORKER_INITIALIZED    0x0001
 #define PROXY_WORKER_IGNORE_ERRORS  0x0002
+#define PROXY_WORKER_DRAIN          0x0004
 #define PROXY_WORKER_IN_SHUTDOWN    0x0010
 #define PROXY_WORKER_DISABLED       0x0020
 #define PROXY_WORKER_STOPPED        0x0040
 #define PROXY_WORKER_IN_ERROR       0x0080
 #define PROXY_WORKER_HOT_STANDBY    0x0100
+#define PROXY_WORKER_FREE           0x0200
 
 #define PROXY_WORKER_NOT_USABLE_BITMAP ( PROXY_WORKER_IN_SHUTDOWN | \
 PROXY_WORKER_DISABLED | PROXY_WORKER_STOPPED | PROXY_WORKER_IN_ERROR )
@@ -290,6 +292,8 @@ typedef struct {
     void            *context;   /* general purpose storage */
     apr_size_t      busy;       /* busyness factor */
     int             lbset;      /* load balancer cluster set */
+    unsigned int    apr_hash;      /* hash #0 of worker name */
+    unsigned int    our_hash;      /* hash #1 of worker name. Why 2? hash collisions. */
 } proxy_worker_stat;
 
 /* Worker configuration */
@@ -343,6 +347,8 @@ struct proxy_worker {
     char            io_buffer_size_set;
     char            keepalive_set;
     char            disablereuse_set;
+    unsigned int    apr_hash;      /* hash #0 of worker name */
+    unsigned int    our_hash;      /* hash #1 of worker name. Why 2? hash collisions. */
 };
 
 /*
@@ -375,6 +381,7 @@ struct proxy_balancer {
     apr_thread_mutex_t  *mutex;  /* Thread lock for updating lb params */
 #endif
     void            *context;         /* general purpose storage */
+    apr_time_t      updated;   /* timestamp of last update */
 };
 
 struct proxy_balancer_method {
@@ -796,6 +803,17 @@ PROXY_DECLARE(void) ap_proxy_backend_broke(request_rec *r,
 PROXY_DECLARE(apr_status_t)
 ap_proxy_buckets_lifetime_transform(request_rec *r, apr_bucket_brigade *from,
                                         apr_bucket_brigade *to);
+/**
+ * Return a hash based on the passed string
+ * @param str     string to produce hash from
+ * @param method  hashing method to use
+ * @return        hash as unsigned int
+ */
+
+typedef enum { PROXY_HASHFUNC_PROXY, PROXY_HASHFUNC_APR } proxy_hash_t;
+
+PROXY_DECLARE(unsigned int)
+ap_proxy_hashfunc(const char *str, proxy_hash_t method);
 
 #define PROXY_LBMETHOD "proxylbmethod"
 

modules/proxy/mod_proxy_balancer.c

@@ -22,11 +22,17 @@
 #include "apr_version.h"
 #include "apr_hooks.h"
 #include "apr_uuid.h"
+#include "apr_date.h"
 
 module AP_MODULE_DECLARE_DATA proxy_balancer_module;
 
 static char balancer_nonce[APR_UUID_FORMATTED_LENGTH + 1];
 
+#if 0
+extern void proxy_update_members(proxy_balancer **balancer, request_rec *r,
+                                  proxy_server_conf *conf);
+#endif
+
 static int proxy_balancer_canon(request_rec *r, char *url)
 {
     char *host, *path;
@@ -468,6 +474,10 @@ static int proxy_balancer_pre_request(proxy_worker **worker,
     /* Step 3: force recovery */
     force_recovery(*balancer, r->server);
     
+    /* Step 3.5: Update member list for the balancer */
+    /* TODO: Implement as provider! */
+    /* proxy_update_members(balancer, r, conf); */
+
     /* Step 4: find the session route */
     runtime = find_session_route(*balancer, r, &route, &sticky, url);
     if (runtime) {

modules/proxy/proxy_util.c

@@ -19,6 +19,7 @@
 #include "ap_mpm.h"
 #include "scoreboard.h"
 #include "apr_version.h"
+#include "apr_hash.h"
 
 #if APR_HAVE_UNISTD_H
 #include <unistd.h>         /* for getpid() */
@@ -1335,6 +1336,7 @@ PROXY_DECLARE(const char *) ap_proxy_add_balancer(proxy_balancer **balancer,
     (*balancer)->name = uri;
     (*balancer)->lbmethod = lbmethod;
     (*balancer)->workers = apr_array_make(p, 5, sizeof(proxy_worker *));
+    (*balancer)->updated = apr_time_now();
     /* XXX Is this a right place to create mutex */
 #if APR_HAS_THREADS
     if (apr_thread_mutex_create(&((*balancer)->mutex),
@@ -1471,6 +1473,7 @@ PROXY_DECLARE(const char *) ap_proxy_add_worker_wid(proxy_worker **worker,
     (*worker)->port = uri.port;
     if (id < 0) {
         (*worker)->id   = proxy_lb_workers;
+        /* Increase the total worker count */
         proxy_lb_workers++;
     } else {
         (*worker)->id   = id;
@@ -1478,13 +1481,22 @@ PROXY_DECLARE(const char *) ap_proxy_add_worker_wid(proxy_worker **worker,
     (*worker)->flush_packets = flush_off;
     (*worker)->flush_wait = PROXY_FLUSH_WAIT;
     (*worker)->smax = -1;
-    /* Increase the total worker count */
+    (*worker)->our_hash = ap_proxy_hashfunc((*worker)->name, PROXY_HASHFUNC_PROXY);
+    (*worker)->apr_hash = ap_proxy_hashfunc((*worker)->name, PROXY_HASHFUNC_APR);
     (*worker)->cp = NULL;
     (*worker)->mutex = NULL;
 
     return NULL;
 }
 
+PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker,
+                                                apr_pool_t *p,
+                                                proxy_server_conf *conf,
+                                                const char *url)
+{
+    return ap_proxy_add_worker_wid(worker, p, conf, url, -1);
+}
+
 PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker_wid(apr_pool_t *p, int id)
 {
 
@@ -1504,6 +1516,11 @@ PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker_wid(apr_pool_t *p, int id)
     return worker;
 }
 
+PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker(apr_pool_t *p)
+{
+    return ap_proxy_create_worker_wid(p, -1);
+}
+
 PROXY_DECLARE(void)
 ap_proxy_add_worker_to_balancer_wid(apr_pool_t *pool, proxy_balancer *balancer,
                                 proxy_worker *worker, int id)
@@ -1519,22 +1536,10 @@ ap_proxy_add_worker_to_balancer_wid(apr_pool_t *pool, proxy_balancer *balancer,
     } else {
         (*runtime)->id = id;
     }
+    balancer->updated = apr_time_now();
 
 }
 
-PROXY_DECLARE(const char *) ap_proxy_add_worker(proxy_worker **worker,
-                                                apr_pool_t *p,
-                                                proxy_server_conf *conf,
-                                                const char *url)
-{
-    return ap_proxy_add_worker_wid(worker, p, conf, url, -1);
-}
-
-PROXY_DECLARE(proxy_worker *) ap_proxy_create_worker(apr_pool_t *p)
-{
-    return ap_proxy_create_worker_wid(p, -1);
-}
-
 PROXY_DECLARE(void)
 ap_proxy_add_worker_to_balancer(apr_pool_t *pool, proxy_balancer *balancer,
                                 proxy_worker *worker)
@@ -1896,6 +1901,8 @@ PROXY_DECLARE(void) ap_proxy_initialize_worker_share(proxy_server_conf *conf,
     }
 
     worker->s->status |= (worker->status | PROXY_WORKER_INITIALIZED);
+    worker->s->apr_hash = worker->apr_hash;
+    worker->s->our_hash = worker->our_hash;
 
 }
 
@@ -2744,3 +2751,27 @@ ap_proxy_buckets_lifetime_transform(request_rec *r, apr_bucket_brigade *from,
     }
     return rv;
 }
+
+/*
+ * Provide a string hashing function for the proxy.
+ * We offer 2 method: one is the APR model but we
+ * also provide our own, based on SDBM. The reason
+ * is in case we want to use both to ensure no
+ * collisions
+ */
+PROXY_DECLARE(unsigned int)
+ap_proxy_hashfunc(const char *str, proxy_hash_t method)
+{
+    if (method == PROXY_HASHFUNC_APR) {
+        apr_ssize_t slen = strlen(str);
+        return apr_hashfunc_default(str, &slen);
+    } else {
+        /* SDBM model */
+        unsigned int hash;
+        for(hash = 0; *str; str++) {
+            hash = (*str) + (hash << 6) + (hash << 16) - hash;
+        }
+        return hash;
+    }
+    
+}