b=20978 Fix llog_process_lock scalability issues.

i=andrew.perepechko
i=rahul.deshmukh

fix llog_process_lock scalability issues during normal start up due to
slow stale export processing.

diff --git a/libcfs/include/libcfs/libcfs_private.h b/libcfs/include/libcfs/libcfs_private.h
index b1dad03..02cd0f8 100644 (file)
--- a/libcfs/include/libcfs/libcfs_private.h
+++ b/libcfs/include/libcfs/libcfs_private.h
@@ -158,7 +158,7 @@ do {                                            \
 # define libcfs_kmem_dec(ptr, size) do {} while (0)
 #endif /* LIBCFS_DEBUG */
 
-#define LIBCFS_VMALLOC_SIZE        16384
+#define LIBCFS_VMALLOC_SIZE        (2 << CFS_PAGE_SHIFT) /* 2 pages */
 
 #define LIBCFS_ALLOC_GFP(ptr, size, mask)                                 \
 do {                                                                      \
@@ -176,8 +176,7 @@ do {                                                                      \
                 break;                                                    \
         }                                                                 \
         libcfs_kmem_inc((ptr), (size));                                   \
-        if (!((mask) & CFS_ALLOC_ZERO))                                   \
-                memset((ptr), 0, (size));                                 \
+        memset((ptr), 0, (size));                                         \
         CDEBUG(D_MALLOC, "kmalloced '" #ptr "': %d at %p (tot %d).\n",    \
                (int)(size), (ptr), cfs_atomic_read (&libcfs_kmemory));    \
 } while (0)

diff --git a/lustre/include/obd_class.h b/lustre/include/obd_class.h
index 611c6e4..dbf25cc 100644 (file)
--- a/lustre/include/obd_class.h
+++ b/lustre/include/obd_class.h
@@ -156,6 +156,7 @@ struct config_llog_data {
         cfs_atomic_t                cld_refcount;
         struct config_llog_data    *cld_sptlrpc;/* depended sptlrpc log */
         struct obd_export          *cld_mgcexp;
+        cfs_mutex_t                 cld_lock;
         unsigned int                cld_stopping:1, /* we were told to stop
                                                      * watching */
                                     cld_lostlock:1, /* lock not requeued */

diff --git a/lustre/mgc/mgc_request.c b/lustre/mgc/mgc_request.c
index df6122c..47eb2bf 100644 (file)
--- a/lustre/mgc/mgc_request.c
+++ b/lustre/mgc/mgc_request.c
@@ -221,6 +221,7 @@ struct config_llog_data *do_config_log_add(struct obd_device *obd,
         strcpy(cld->cld_logname, logname);
         if (cfg)
                 cld->cld_cfg = *cfg;
+        cfs_mutex_init(&cld->cld_lock);
         cld->cld_cfg.cfg_last_idx = 0;
         cld->cld_cfg.cfg_flags = 0;
         cld->cld_cfg.cfg_sb = sb;
@@ -325,7 +326,7 @@ static int config_log_end(char *logname, struct config_llog_instance *cfg)
         if (IS_ERR(cld))
                 RETURN(PTR_ERR(cld));
 
-        cfs_down(&llog_process_lock);
+        cfs_mutex_lock(&cld->cld_lock);
         /*
          * if cld_stopping is set, it means we didn't start the log thus
          * not owning the start ref. this can happen after previous umount:
@@ -334,14 +335,14 @@ static int config_log_end(char *logname, struct config_llog_instance *cfg)
          * calling start_log.
          */
         if (unlikely(cld->cld_stopping)) {
-                cfs_up(&llog_process_lock);
+                cfs_mutex_unlock(&cld->cld_lock);
                 /* drop the ref from the find */
                 config_log_put(cld);
                 RETURN(rc);
         }
 
         cld->cld_stopping = 1;
-        cfs_up(&llog_process_lock);
+        cfs_mutex_unlock(&cld->cld_lock);
 
         cfs_spin_lock(&config_list_lock);
         cld_sptlrpc = cld->cld_sptlrpc;
@@ -1264,10 +1265,10 @@ int mgc_process_log(struct obd_device *mgc,
            sounds like badness.  It actually might be fine, as long as
            we're not trying to update from the same log
            simultaneously (in which case we should use a per-log sem.) */
-        cfs_down(&llog_process_lock);
+        cfs_mutex_lock(&cld->cld_lock);
 
         if (cld->cld_stopping) {
-                cfs_up(&llog_process_lock);
+                cfs_mutex_unlock(&cld->cld_lock);
                 RETURN(0);
         }
 
@@ -1282,7 +1283,7 @@ int mgc_process_log(struct obd_device *mgc,
         ctxt = llog_get_context(mgc, LLOG_CONFIG_REPL_CTXT);
         if (!ctxt) {
                 CERROR("missing llog context\n");
-                cfs_up(&llog_process_lock);
+                cfs_mutex_unlock(&cld->cld_lock);
                 RETURN(-EINVAL);
         }
 
@@ -1369,7 +1370,7 @@ out_pop:
         CDEBUG(D_MGC, "%s: configuration from log '%s' %sed (%d).\n",
                mgc->obd_name, cld->cld_logname, rc ? "fail" : "succeed", rc);
 
-        cfs_up(&llog_process_lock);
+        cfs_mutex_unlock(&cld->cld_lock);
 
         RETURN(rc);
 }