mem-pool: add tracking of mem_pool that requested the allocation

This renames the current 'struct mem_pool' to 'struct mem_pool_shared'.
The mem_pool_shared is globally allocated and not specific for
particular objects.

A new 'struct mem_pool' gets allocated when mem_pool_new() is called. It
points to the mem_pool_shared that handles the actual allocation
requests. The 'struct mem_pool' is only used for accounting of the
objects that the caller requested and free'd.

All of these changes will be used to collect all the memory pools a
glusterfs_ctx_t is consuming, so that statedumps can be collected per
context.

Updates: #307
Change-Id: I6355d3f0251c928e0bbfc71be3431307c6f3a3da
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Reviewed-on: https://review.gluster.org/18073
Smoke: Gluster Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Amar Tumballi <amarts@redhat.com>
Reviewed-by: Jeff Darcy <jeff@pl.atyp.us>

3 files changed, 49 insertions, 33 deletions

diff --git a/libglusterfs/src/mem-pool.c b/libglusterfs/src/mem-pool.c
index ba29137b176..8bd9779ce81 100644
--- a/libglusterfs/src/mem-pool.c
+++ b/libglusterfs/src/mem-pool.c
@@ -14,16 +14,6 @@
 #include <stdlib.h>
 #include <stdarg.h>
 
-#define GF_MEM_POOL_LIST_BOUNDARY        (sizeof(struct list_head))
-#define GF_MEM_POOL_PTR                  (sizeof(struct mem_pool*))
-#define GF_MEM_POOL_PAD_BOUNDARY         (GF_MEM_POOL_LIST_BOUNDARY  + GF_MEM_POOL_PTR + sizeof(int))
-#define mem_pool_chunkhead2ptr(head)     ((head) + GF_MEM_POOL_PAD_BOUNDARY)
-#define mem_pool_ptr2chunkhead(ptr)      ((ptr) - GF_MEM_POOL_PAD_BOUNDARY)
-#define is_mem_chunk_in_use(ptr)         (*ptr == 1)
-#define mem_pool_from_ptr(ptr)           ((ptr) + GF_MEM_POOL_LIST_BOUNDARY)
-
-#define GLUSTERFS_ENV_MEM_ACCT_STR  "GLUSTERFS_DISABLE_MEM_ACCT"
-
 #include "unittest/unittest.h"
 #include "libglusterfs-messages.h"
 
@@ -380,7 +370,7 @@ static pthread_mutex_t          pool_lock       = PTHREAD_MUTEX_INITIALIZER;
 static struct list_head         pool_threads;
 static pthread_mutex_t          pool_free_lock  = PTHREAD_MUTEX_INITIALIZER;
 static struct list_head         pool_free_threads;
-static struct mem_pool          pools[NPOOLS];
+static struct mem_pool_shared   pools[NPOOLS];
 static size_t                   pool_list_size;
 
 #if !defined(GF_DISABLE_MEMPOOL)
@@ -677,6 +667,8 @@ mem_pool_new_fn (unsigned long sizeof_type,
                  unsigned long count, char *name)
 {
         unsigned int            i;
+        struct mem_pool         *new = NULL;
+        struct mem_pool_shared  *pool = NULL;
 
         if (!sizeof_type) {
                 gf_msg_callingfn ("mem-pool", GF_LOG_ERROR, EINVAL,
@@ -686,13 +678,27 @@ mem_pool_new_fn (unsigned long sizeof_type,
 
         for (i = 0; i < NPOOLS; ++i) {
                 if (sizeof_type <= AVAILABLE_SIZE(pools[i].power_of_two)) {
-                        return &pools[i];
+                        pool = &pools[i];
+                        break;
                 }
         }
 
-        gf_msg_callingfn ("mem-pool", GF_LOG_ERROR, EINVAL,
-                          LG_MSG_INVALID_ARG, "invalid argument");
-        return NULL;
+        if (!pool) {
+                gf_msg_callingfn ("mem-pool", GF_LOG_ERROR, EINVAL,
+                                  LG_MSG_INVALID_ARG, "invalid argument");
+                return NULL;
+        }
+
+        new = GF_CALLOC (sizeof (struct mem_pool), 1, gf_common_mt_mem_pool);
+        if (!new)
+                return NULL;
+
+        new->sizeof_type = sizeof_type;
+        new->count = count;
+        new->name = name;
+        new->pool = pool;
+
+        return new;
 }
 
 void*
@@ -709,7 +715,7 @@ mem_get0 (struct mem_pool *mem_pool)
         ptr = mem_get(mem_pool);
 
         if (ptr) {
-                memset (ptr, 0, AVAILABLE_SIZE(mem_pool->power_of_two));
+                memset (ptr, 0, AVAILABLE_SIZE(mem_pool->pool->power_of_two));
         }
 
         return ptr;
@@ -788,7 +794,7 @@ void *
 mem_get (struct mem_pool *mem_pool)
 {
 #if defined(GF_DISABLE_MEMPOOL)
-        return GF_CALLOC (1, AVAILABLE_SIZE (mem_pool->power_of_two),
+        return GF_CALLOC (1, AVAILABLE_SIZE (mem_pool->pool->power_of_two),
                           gf_common_mt_mem_pool);
 #else
         per_thread_pool_list_t  *pool_list;
@@ -807,7 +813,7 @@ mem_get (struct mem_pool *mem_pool)
         }
 
         (void) pthread_spin_lock (&pool_list->lock);
-        pt_pool = &pool_list->pools[mem_pool->power_of_two-POOL_SMALLEST];
+        pt_pool = &pool_list->pools[mem_pool->pool->power_of_two-POOL_SMALLEST];
         retval = mem_get_from_pool (pt_pool);
         (void) pthread_spin_unlock (&pool_list->lock);
 
@@ -816,9 +822,9 @@ mem_get (struct mem_pool *mem_pool)
         }
 
         retval->magic = GF_MEM_HEADER_MAGIC;
-        retval->next = NULL;
-        retval->pool_list = pool_list;;
-        retval->power_of_two = mem_pool->power_of_two;
+        retval->pool = mem_pool;
+        retval->pool_list = pool_list;
+        retval->power_of_two = mem_pool->pool->power_of_two;
 
         return retval + 1;
 #endif /* GF_DISABLE_MEMPOOL */
@@ -861,14 +867,12 @@ mem_put (void *ptr)
 void
 mem_pool_destroy (struct mem_pool *pool)
 {
-        if (!pool)
-                return;
+        GF_FREE (pool);
 
         /*
-         * Pools are now permanent, so this does nothing.  Yes, this means we
-         * can keep allocating from a pool after calling mem_destroy on it, but
-         * that's kind of OK.  All of the objects *in* the pool will eventually
-         * be freed via the pool-sweeper thread, and this way we don't have to
-         * add a lot of reference-counting complexity.
+         * Pools are now permanent, so the mem_pool->pool is kept around. All
+         * of the objects *in* the pool will eventually be freed via the
+         * pool-sweeper thread, and this way we don't have to add a lot of
+         * reference-counting complexity.
          */
 }
diff --git a/libglusterfs/src/mem-pool.h b/libglusterfs/src/mem-pool.h
index 1272ad4d5fc..cc7df0b77c8 100644
--- a/libglusterfs/src/mem-pool.h
+++ b/libglusterfs/src/mem-pool.h
@@ -203,18 +203,31 @@ out:
         return dup_mem;
 }
 
+/* kind of 'header' for the actual mem_pool_shared structure, this might make
+ * it possible to dump some more details in a statedump */
+struct mem_pool {
+        unsigned long           sizeof_type;
+        unsigned long           count;
+        char                    *name;
+
+        struct mem_pool_shared  *pool;
+};
+
 typedef struct pooled_obj_hdr {
         unsigned long                   magic;
         struct pooled_obj_hdr           *next;
         struct per_thread_pool_list     *pool_list;
         unsigned int                    power_of_two;
+
+        /* track the pool that was used to request this object */
+        struct mem_pool                 *pool;
 } pooled_obj_hdr_t;
 
 #define AVAILABLE_SIZE(p2)      ((1 << (p2)) - sizeof(pooled_obj_hdr_t))
 
 typedef struct per_thread_pool {
-        /* This never changes, so doesn't need a lock. */
-        struct mem_pool         *parent;
+        /* the pool that was used to request this allocation */
+        struct mem_pool_shared  *parent;
         /* Everything else is protected by our own lock. */
         pooled_obj_hdr_t        *hot_list;
         pooled_obj_hdr_t        *cold_list;
@@ -242,7 +255,8 @@ typedef struct per_thread_pool_list {
         per_thread_pool_t       pools[1];
 } per_thread_pool_list_t;
 
-struct mem_pool {
+/* actual pool structure, shared between different mem_pools */
+struct mem_pool_shared {
         unsigned int            power_of_two;
         /*
          * Updates to these are *not* protected by a global lock, so races
diff --git a/libglusterfs/src/mem-types.h b/libglusterfs/src/mem-types.h
index d244fb528e3..c2ac088f639 100644
--- a/libglusterfs/src/mem-types.h
+++ b/libglusterfs/src/mem-types.h
@@ -61,9 +61,7 @@ enum gf_common_mem_types_ {
         gf_common_mt_char,
         gf_common_mt_rbthash_table_t,
         gf_common_mt_rbthash_bucket,
-#if defined(GF_DISABLE_MEMPOOL)
         gf_common_mt_mem_pool,
-#endif
         gf_common_mt_long,
         gf_common_mt_rpcsvc_auth_list,
         gf_common_mt_rpcsvc_t,