core/memacct: save allocs in mem_acct_rec list

With configure --enable-debug, add all object allocations
to a list in the corresponding mem_acct_rec. This
allows us to see all objects of a particular type
and allows for additional debugging in case of memory
leaks.

This is not compiled in by default and must be explicitly
enabled. It is intended to be used by developers.

> Change-Id: I7cf2dbeadecf994423d7e7591e85f18d2575cce8
> BUG: 1522662
> Signed-off-by: N Balachandran <nbalacha@redhat.com>

(cherry picked from commit 47d01546a1826dc14a8331ea8700015f1cfdc4db)
Change-Id: I7cf2dbeadecf994423d7e7591e85f18d2575cce8
BUG: 1523455
Signed-off-by: N Balachandran <nbalacha@redhat.com>

1 files changed, 33 insertions, 1 deletions

diff --git a/libglusterfs/src/mem-pool.c b/libglusterfs/src/mem-pool.c
index ba29137b176..c8c4aa9af6d 100644
--- a/libglusterfs/src/mem-pool.c
+++ b/libglusterfs/src/mem-pool.c
@@ -88,8 +88,16 @@ gf_mem_set_acct_info (xlator_t *xl, char **alloc_ptr, size_t size,
         header->mem_acct = xl->mem_acct;
         header->magic = GF_MEM_HEADER_MAGIC;
 
+#ifdef DEBUG
+        INIT_LIST_HEAD(&header->acct_list);
+        LOCK(&xl->mem_acct->rec[type].lock);
+        {
+                list_add (&header->acct_list,
+                          &(xl->mem_acct->rec[type].obj_list));
+        }
+        UNLOCK(&xl->mem_acct->rec[type].lock);
+#endif
         ptr += sizeof (struct mem_header);
-
         /* data follows in this gap of 'size' bytes */
         *(uint32_t *) (ptr + size) = GF_MEM_TRAILER_MAGIC;
 
@@ -167,6 +175,27 @@ __gf_realloc (void *ptr, size_t size)
         GF_ASSERT (old_header->magic == GF_MEM_HEADER_MAGIC);
         tmp_header = *old_header;
 
+#ifdef DEBUG
+        int type = 0;
+        size_t copy_size = 0;
+
+        /* Making these changes for realloc is not straightforward. So
+         * I am simulating realloc using calloc and free
+         */
+
+        type = tmp_header.type;
+        new_ptr = __gf_calloc (1, size, type,
+                               tmp_header.mem_acct->rec[type].typestr);
+        if (new_ptr) {
+                copy_size = (size > tmp_header.size) ? tmp_header.size : size;
+                memcpy (new_ptr, ptr, copy_size);
+                __gf_free (ptr);
+        }
+
+        /* This is not quite what the man page says should happen */
+        return new_ptr;
+#endif
+
         tot_size = size + GF_MEM_HEADER_SIZE + GF_MEM_TRAILER_SIZE;
         new_ptr = realloc (old_header, tot_size);
         if (!new_ptr) {
@@ -323,6 +352,9 @@ __gf_free (void *free_ptr)
                  * to NULL */
                 if (!mem_acct->rec[header->type].num_allocs)
                         mem_acct->rec[header->type].typestr = NULL;
+#ifdef DEBUG
+                list_del (&header->acct_list);
+#endif
         }
         UNLOCK (&mem_acct->rec[header->type].lock);