Crude stat segment lock recovery

Make sure that vpp_get_stats main heap does not address-collide with
the stats segment, which lands "somewhere" in the vpp address space.

Add mising MAP_ANONYMOUS flag in clib_mem_vm_map

Change-Id: I8a671d174eefd8dd24771ad2ed9f1250e2c7a9f8
Signed-off-by: Dave Barach <dave@barachs.net>
Signed-off-by: Ole Troan <ot@cisco.com>

4 files changed, 31 insertions, 17 deletions

diff --git a/src/vpp/app/vpp_get_stats.c b/src/vpp/app/vpp_get_stats.c
index 86e511e56f2..c1f43a747ed 100644
--- a/src/vpp/app/vpp_get_stats.c
+++ b/src/vpp/app/vpp_get_stats.c
@@ -108,8 +108,10 @@ main (int argc, char **argv)
   u8 *stat_segment_name, *pattern = 0, **patterns = 0;
   int rv;
   enum stat_client_cmd_e cmd = STAT_CLIENT_CMD_UNKNOWN;
+  void *heap_base;
 
-  clib_mem_init (0, 128 << 20);
+  heap_base = clib_mem_vm_map ((void *) 0x10000000ULL, 128 << 20);
+  clib_mem_init (heap_base, 128 << 20);
 
   unformat_init_command_line (a, argv);
 
diff --git a/src/vpp/app/vpp_prometheus_export.c b/src/vpp/app/vpp_prometheus_export.c
index 57c65178c73..cc85b817063 100644
--- a/src/vpp/app/vpp_prometheus_export.c
+++ b/src/vpp/app/vpp_prometheus_export.c
@@ -223,8 +223,10 @@ main (int argc, char **argv)
   unformat_input_t _argv, *a = &_argv;
   u8 *stat_segment_name, *pattern = 0, **patterns = 0;
   int rv;
+  void *heap_base;
 
-  clib_mem_init (0, 128 << 20);
+  heap_base = clib_mem_vm_map ((void *) 0x10000000ULL, 128 << 20);
+  clib_mem_init (heap_base, 128 << 20);
 
   unformat_init_command_line (a, argv);
 
diff --git a/src/vpp/stats/stat_segment.c b/src/vpp/stats/stat_segment.c
index 8459138be34..dcaeb5078b3 100644
--- a/src/vpp/stats/stat_segment.c
+++ b/src/vpp/stats/stat_segment.c
@@ -18,7 +18,20 @@ void
 vlib_stat_segment_lock (void)
 {
   stats_main_t *sm = &stats_main;
-  clib_spinlock_lock (sm->stat_segment_lockp);
+  vlib_main_t *vm = vlib_get_main ();
+  f64 deadman;
+
+  /* 3ms is WAY long enough to be reasonably sure something is wrong */
+  deadman = vlib_time_now (vm) + 3e-3;
+
+  while (__sync_lock_test_and_set (&((*sm->stat_segment_lockp)->lock), 1))
+    {
+      if (vlib_time_now (vm) >= deadman)
+	{
+	  clib_warning ("BUG: stat segment lock held too long...");
+	  break;
+	}
+    }
 }
 
 void
@@ -66,7 +79,7 @@ vlib_stats_pop_heap (void *cm_arg, void *oldheap, stat_directory_type_t type)
       stat_segment_name = cm->stat_segment_name ?
 	cm->stat_segment_name : cm->name;
 
-      clib_spinlock_lock (sm->stat_segment_lockp);
+      vlib_stat_segment_lock ();
 
       /* Update hash table. The name must be copied into the segment */
       hp = hash_get_pair (sm->counter_vector_by_name, stat_segment_name);
@@ -91,7 +104,7 @@ vlib_stats_pop_heap (void *cm_arg, void *oldheap, stat_directory_type_t type)
       /* Warn clients to refresh any pointers they might be holding */
       shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] = (void *)
 	((u64) shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] + 1);
-      clib_spinlock_unlock (sm->stat_segment_lockp);
+      vlib_stat_segment_unlock ();
     }
   ssvm_pop_heap (oldheap);
 }
@@ -111,8 +124,7 @@ vlib_stats_register_error_index (u8 * name, u64 index)
 
   shared_header = ssvmp->sh;
 
-  clib_spinlock_lock (sm->stat_segment_lockp);
-
+  vlib_stat_segment_lock ();
   /* Update hash table. The name must be copied into the segment */
   hp = hash_get_pair (sm->counter_vector_by_name, name);
   if (hp)
@@ -136,7 +148,7 @@ vlib_stats_register_error_index (u8 * name, u64 index)
   /* Warn clients to refresh any pointers they might be holding */
   shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] = (void *)
     ((u64) shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] + 1);
-  clib_spinlock_unlock (sm->stat_segment_lockp);
+  vlib_stat_segment_unlock ();
 }
 
 void
@@ -155,8 +167,7 @@ vlib_stats_pop_heap2 (u64 * counter_vector, u32 thread_index, void *oldheap)
 
   shared_header = ssvmp->sh;
 
-  clib_spinlock_lock (sm->stat_segment_lockp);
-
+  vlib_stat_segment_lock ();
   error_vector_name = format (0, "/err/%d/counter_vector%c", thread_index, 0);
 
   /* Update hash table. The name must be copied into the segment */
@@ -182,7 +193,7 @@ vlib_stats_pop_heap2 (u64 * counter_vector, u32 thread_index, void *oldheap)
   /* Warn clients to refresh any pointers they might be holding */
   shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] = (void *)
     ((u64) shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] + 1);
-  clib_spinlock_unlock (sm->stat_segment_lockp);
+  vlib_stat_segment_unlock ();
   ssvm_pop_heap (oldheap);
 }
 
@@ -359,7 +370,7 @@ show_stat_segment_command_fn (vlib_main_t * vm,
   if (unformat (input, "verbose"))
     verbose = 1;
 
-  clib_spinlock_lock (sm->stat_segment_lockp);
+  vlib_stat_segment_lock ();
 
   /* *INDENT-OFF* */
   hash_foreach_pair (p, sm->counter_vector_by_name,
@@ -371,7 +382,7 @@ show_stat_segment_command_fn (vlib_main_t * vm,
   }));
   /* *INDENT-ON* */
 
-  clib_spinlock_unlock (sm->stat_segment_lockp);
+  vlib_stat_segment_unlock ();
 
   vec_sort_with_function (show_data, name_sort_cmp);
 
@@ -427,8 +438,7 @@ update_serialized_nodes (stats_main_t * sm)
 
   oldheap = ssvm_push_heap (shared_header);
 
-  clib_spinlock_lock (sm->stat_segment_lockp);
-
+  vlib_stat_segment_lock ();
   vlib_node_get_nodes (0 /* vm, for barrier sync */ ,
 		       (u32) ~ 0 /* all threads */ ,
 		       1 /* include stats */ ,
@@ -471,7 +481,7 @@ update_serialized_nodes (stats_main_t * sm)
 	((u64) shared_header->opaque[STAT_SEGMENT_OPAQUE_EPOCH] + 1);
     }
 
-  clib_spinlock_unlock (sm->stat_segment_lockp);
+  vlib_stat_segment_unlock ();
   ssvm_pop_heap (oldheap);
 }
 
diff --git a/src/vppinfra/mem.h b/src/vppinfra/mem.h
index 1646072e72f..0702aabb90a 100644
--- a/src/vppinfra/mem.h
+++ b/src/vppinfra/mem.h
@@ -348,7 +348,7 @@ always_inline void *
 clib_mem_vm_map (void *addr, uword size)
 {
   void *mmap_addr;
-  uword flags = MAP_PRIVATE | MAP_FIXED;
+  uword flags = MAP_PRIVATE | MAP_FIXED | MAP_ANONYMOUS;
 
   mmap_addr = mmap (addr, size, (PROT_READ | PROT_WRITE), flags, -1, 0);
   if (mmap_addr == (void *) -1)