Stability hack. Under Solaris when KM_SLEEP is set kmem_cache_alloc()

may not fail.  To get this behavior I'd added a retry to the shim layer
even though it is abusive to the VM, at least it should prevent the crash.
Additionally I added a proc counter so I can easily check how often this
is happening.  It should be fairly rare, but likely will get worse and
worse the longer the machine has been up.


git-svn-id: https://outreach.scidac.gov/svn/spl/trunk@104 7e1ea52c-4ff2-0310-8f11-9dd32ca42a1c

modules/spl/spl-proc.c

@@ -60,6 +60,7 @@ enum {
         CTL_KMEM_KMEMMAX,         /* Max alloc'd by kmem bytes */
         CTL_KMEM_VMEMUSED,        /* Currently alloc'd vmem bytes */
         CTL_KMEM_VMEMMAX,         /* Max alloc'd by vmem bytes */
+	CTL_KMEM_ALLOC_FAILED,    /* Cache allocation failed */
 #endif
 
 	CTL_MUTEX_STATS,          /* Global mutex statistics */
@@ -660,6 +661,14 @@ static struct ctl_table spl_kmem_table[] = {
                 .mode     = 0444,
                 .proc_handler = &proc_doulongvec_minmax,
         },
+        {
+                .ctl_name = CTL_KMEM_ALLOC_FAILED,
+                .procname = "kmem_alloc_failed",
+                .data     = &kmem_cache_alloc_failed,
+                .maxlen   = sizeof(atomic64_t),
+                .mode     = 0444,
+                .proc_handler = &proc_doatomic64,
+        },
 	{0},
 };
 #endif /* DEBUG_KMEM */