OS-11 rcapd behaves poorly when under extreme load
OS-399 zone phys. mem. cap should be a rctl and have associated kstat

@@ -19,81 +19,138 @@
  * CDDL HEADER END
  */
 /*
  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
  * Use is subject to license terms.
+ * Copyright 2011 Joyent, Inc.  All rights reserved.
  */
 
-#pragma ident   "%Z%%M% %I%     %E% SMI"
-
 #include <procfs.h>
 #include <project.h>
 #include <stdlib.h>
 #include <strings.h>
 #include <zone.h>
 #include <libzonecfg.h>
+#include <dirent.h>
+#include <libproc.h>
 #include "rcapd.h"
 #include "utils.h"
 
 extern boolean_t gz_capped;
 
                                 /* round up to next y = 2^n */
 #define ROUNDUP(x, y)           (((x) + ((y) - 1)) & ~((y) - 1))
 
-static void
-update_zone(zone_entry_t *zent, void *walk_data)
+static struct ps_prochandle *
+grab_zone_proc(zoneid_t zid)
 {
-        void(*update_notification_cb)(char *, char *, int, uint64_t, int) =
-            (void(*)(char *, char *, int, uint64_t, int))walk_data;
-        int changes;
-        int64_t max_rss;
+        DIR *dirp;
+        struct dirent *dentp;
+        int pid, pid_self, tmp;
+        psinfo_t psinfo;
+        struct ps_prochandle *pr = NULL;
+
+        pid_self = getpid();
+
+        if ((dirp = opendir("/proc")) == NULL)
+                return (NULL);
+
+        while (dentp = readdir(dirp)) {
+                pid = atoi(dentp->d_name);
+
+                /* Skip self */
+                if (pid == pid_self)
+                        continue;
+
+                if (proc_get_psinfo(pid, &psinfo) != 0)
+                        continue;
+
+                if (psinfo.pr_zoneid != zid)
+                        continue;
+
+                /* attempt to grab process */
+                if ((pr = Pgrab(pid, 0, &tmp)) != NULL) {
+                        if (Psetflags(pr, PR_RLC) != 0) {
+                                Prelease(pr, 0);
+                        }
+                        if (Pcreate_agent(pr) == 0) {
+                                if (pr_getzoneid(pr) != zid) {
+                                        Prelease(pr, 0);
+                                        continue;
+                                }
+
+                                (void) closedir(dirp);
+                                return (pr);
+                        } else {
+                                Prelease(pr, 0);
+                        }
+                }
+        }
+
+        (void) closedir(dirp);
+        return (NULL);
+}
+
+static uint64_t
+get_zone_cap(zoneid_t zid)
+{
+        rctlblk_t *rblk;
         uint64_t mcap;
-        lcollection_t *lcol;
-        rcid_t colid;
+        struct ps_prochandle *pr;
 
-        if (zone_getattr(zent->zid, ZONE_ATTR_PHYS_MCAP, &mcap,
-            sizeof (mcap)) != -1 && mcap != 0)
-                max_rss = ROUNDUP(mcap, 1024) / 1024;
-        else
-                max_rss = 0;
+        if ((rblk = (rctlblk_t *)malloc(rctlblk_size())) == NULL)
+                return (UINT64_MAX);
 
-        if (zent->zid == GLOBAL_ZONEID) {
-                if (max_rss > 0)
-                        gz_capped = B_TRUE;
-                else
-                        gz_capped = B_FALSE;
+        if ((pr = grab_zone_proc(zid)) == NULL) {
+                free(rblk);
+                return (UINT64_MAX);
         }
 
+        if (pr_getrctl(pr, "zone.max-physical-memory", NULL, rblk,
+            RCTL_FIRST)) {
+                Pdestroy_agent(pr);
+                Prelease(pr, 0);
+                free(rblk);
+                return (UINT64_MAX);
+        }
 
-        colid.rcid_type = RCIDT_ZONE;
-        colid.rcid_val = zent->zid;
+        Pdestroy_agent(pr);
+        Prelease(pr, 0);
 
-        lcol = lcollection_insert_update(&colid, max_rss, zent->zname,
-            &changes);
-        if (update_notification_cb != NULL)
-                update_notification_cb("zone", zent->zname, changes, max_rss,
-                    (lcol != NULL) ? lcol->lcol_mark : 0);
+        mcap = rctlblk_get_value(rblk);
+        free(rblk);
+        return (mcap);
 }
 
-
+/*
+ * For zones, rcapd only caps the global zone, since each non-global zone
+ * caps itself.
+ */
 /* ARGSUSED */
 void
 lcollection_update_zone(lcollection_update_type_t ut,
     void(*update_notification_cb)(char *, char *, int, uint64_t, int))
 {
-        int i;
-        uint_t nzents;
-        zone_entry_t *zents;
+        int changes;
+        int64_t max_rss;
+        uint64_t mcap;
+        lcollection_t *lcol;
+        rcid_t colid;
 
-        /*
-         * Enumerate running zones.
-         */
-        if (get_running_zones(&nzents, &zents) != 0)
-                return;
-
-        for (i = 0; i < nzents; i++) {
-                update_zone(&zents[i], (void *)update_notification_cb);
-
+        mcap = get_zone_cap(GLOBAL_ZONEID);
+        if (mcap != 0 && mcap != UINT64_MAX) {
+                max_rss = ROUNDUP(mcap, 1024) / 1024;
+                gz_capped = B_TRUE;
+        } else {
+                max_rss = UINT64_MAX / 1024;
+                gz_capped = B_FALSE;
         }
 
-        free(zents);
+        colid.rcid_type = RCIDT_ZONE;
+        colid.rcid_val = GLOBAL_ZONEID;
+
+        lcol = lcollection_insert_update(&colid, max_rss, GLOBAL_ZONENAME,
+            &changes);
+        if (update_notification_cb != NULL)
+                update_notification_cb("zone", GLOBAL_ZONENAME, changes,
+                    max_rss, (lcol != NULL) ? lcol->lcol_mark : 0);
 }