Revert "iobuf: Get rid of pre allocated iobuf_pool and use per thread mem pool"

This reverts commit b87c397091bac6a4a6dec4e45a7671fad4a11770.

There seems to be some performance regression with the patch and hence recommended to have it reverted.

Updates: #325
Change-Id: Id85d6203173a44fad6cf51d39b3e96f37afcec09

1 files changed, 97 insertions, 14 deletions

diff --git a/libglusterfs/src/glusterfs/iobuf.h b/libglusterfs/src/glusterfs/iobuf.h
index 7516bc8034b..6de0f13ae36 100644
--- a/libglusterfs/src/glusterfs/iobuf.h
+++ b/libglusterfs/src/glusterfs/iobuf.h
@@ -17,38 +17,118 @@
 #include <sys/mman.h>
 #include <sys/uio.h>
 
+#define GF_VARIABLE_IOBUF_COUNT 32
+
+#define GF_RDMA_DEVICE_COUNT 8
+
+/* Lets try to define the new anonymous mapping
+ * flag, in case the system is still using the
+ * now deprecated MAP_ANON flag.
+ *
+ * Also, this should ideally be in a centralized/common
+ * header which can be used by other source files also.
+ */
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
 #define GF_ALIGN_BUF(ptr, bound)                                               \
     ((void *)((unsigned long)(ptr + bound - 1) & (unsigned long)(~(bound - 1))))
 
 #define GF_IOBUF_ALIGN_SIZE 512
 
-#define GF_IOBUF_DEFAULT_PAGE_SIZE (128 * GF_UNIT_KB)
-
 /* one allocatable unit for the consumers of the IOBUF API */
 /* each unit hosts @page_size bytes of memory */
 struct iobuf;
 
+/* one region of memory mapped from the operating system */
+/* each region MMAPs @arena_size bytes of memory */
+/* each arena hosts @arena_size / @page_size IOBUFs */
+struct iobuf_arena;
+
 /* expandable and contractable pool of memory, internally broken into arenas */
 struct iobuf_pool;
 
+struct iobuf_init_config {
+    size_t pagesize;
+    int32_t num_pages;
+};
+
 struct iobuf {
-    gf_boolean_t stdalloc; /* indicates whether iobuf is allocated from
-                              mem pool or standard alloc*/
-    gf_lock_t lock;        /* for ->ptr and ->ref */
-    gf_atomic_t ref;       /* 0 == passive, >0 == active */
+    union {
+        struct list_head list;
+        struct {
+            struct iobuf *next;
+            struct iobuf *prev;
+        };
+    };
+    struct iobuf_arena *iobuf_arena;
+
+    gf_lock_t lock;  /* for ->ptr and ->ref */
+    gf_atomic_t ref; /* 0 == passive, >0 == active */
 
     void *ptr; /* usable memory region by the consumer */
 
-    void *free_ptr;                /* in case of stdalloc, this is the
-                                      one to be freed */
-    size_t page_size;              /* iobuf's page size */
-    struct iobuf_pool *iobuf_pool; /* iobuf_pool iobuf is associated with */
+    void *free_ptr; /* in case of stdalloc, this is the
+                       one to be freed */
+};
+
+struct iobuf_arena {
+    union {
+        struct list_head list;
+        struct {
+            struct iobuf_arena *next;
+            struct iobuf_arena *prev;
+        };
+    };
+
+    struct list_head all_list;
+    size_t page_size; /* size of all iobufs in this arena */
+    size_t arena_size;
+    /* this is equal to rounded_size * num_iobufs.
+       (rounded_size comes with gf_iobuf_get_pagesize().) */
+    size_t page_count;
+
+    struct iobuf_pool *iobuf_pool;
+
+    void *mem_base;
+    struct iobuf *iobufs; /* allocated iobufs list */
+
+    int active_cnt;
+    struct iobuf active; /* head node iobuf
+                            (unused by itself) */
+    int passive_cnt;
+    struct iobuf passive; /* head node iobuf
+                             (unused by itself) */
+    uint64_t alloc_cnt;   /* total allocs in this pool */
+    int max_active;       /* max active buffers at a given time */
 };
 
 struct iobuf_pool {
-    gf_atomic_t mem_pool_hit;
-    gf_atomic_t mem_pool_miss;
-    gf_atomic_t active_cnt;
+    pthread_mutex_t mutex;
+    size_t arena_size;        /* size of memory region in
+                                 arena */
+    size_t default_page_size; /* default size of iobuf */
+
+    int arena_cnt;
+    struct list_head all_arenas;
+    struct list_head arenas[GF_VARIABLE_IOBUF_COUNT];
+    /* array of arenas. Each element of the array is a list of arenas
+       holding iobufs of particular page_size */
+
+    struct list_head filled[GF_VARIABLE_IOBUF_COUNT];
+    /* array of arenas without free iobufs */
+
+    struct list_head purge[GF_VARIABLE_IOBUF_COUNT];
+    /* array of of arenas which can be purged */
+
+    uint64_t request_misses; /* mostly the requests for higher
+                               value of iobufs */
+    int rdma_device_count;
+    struct list_head *mr_list[GF_RDMA_DEVICE_COUNT];
+    void *device[GF_RDMA_DEVICE_COUNT];
+    int (*rdma_registration)(void **, void *);
+    int (*rdma_deregistration)(struct list_head **, struct iobuf_arena *);
 };
 
 struct iobuf_pool *
@@ -62,10 +142,13 @@ iobuf_unref(struct iobuf *iobuf);
 struct iobuf *
 iobuf_ref(struct iobuf *iobuf);
 void
+iobuf_pool_destroy(struct iobuf_pool *iobuf_pool);
+void
 iobuf_to_iovec(struct iobuf *iob, struct iovec *iov);
 
 #define iobuf_ptr(iob) ((iob)->ptr)
-#define iobuf_pagesize(iob) (iob->page_size)
+#define iobpool_default_pagesize(iobpool) ((iobpool)->default_page_size)
+#define iobuf_pagesize(iob) (iob->iobuf_arena->page_size)
 
 struct iobref {
     gf_lock_t lock;