aio: remove request submission batching

This should be useless now that we have on-stack plugging. So lets just
kill it.

Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

diff --git a/fs/aio.c b/fs/aio.c
index 1476bed1c5fbd0325bd6b18a989e4b5b67439387..020de5cb4a67f931c63efaba4960585b15f912e4 100644 (file)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -34,8 +34,6 @@
 #include <linux/security.h>
 #include <linux/eventfd.h>
 #include <linux/blkdev.h>
-#include <linux/mempool.h>
-#include <linux/hash.h>
 #include <linux/compat.h>
 
 #include <asm/kmap_types.h>
@@ -65,14 +63,6 @@ static DECLARE_WORK(fput_work, aio_fput_routine);
 static DEFINE_SPINLOCK(fput_lock);
 static LIST_HEAD(fput_head);
 
-#define AIO_BATCH_HASH_BITS    3 /* allocated on-stack, so don't go crazy */
-#define AIO_BATCH_HASH_SIZE    (1 << AIO_BATCH_HASH_BITS)
-struct aio_batch_entry {
-       struct hlist_node list;
-       struct address_space *mapping;
-};
-mempool_t *abe_pool;
-
 static void aio_kick_handler(struct work_struct *);
 static void aio_queue_work(struct kioctx *);
 
@@ -86,8 +76,7 @@ static int __init aio_setup(void)
        kioctx_cachep = KMEM_CACHE(kioctx,SLAB_HWCACHE_ALIGN|SLAB_PANIC);
 
        aio_wq = create_workqueue("aio");
-       abe_pool = mempool_create_kmalloc_pool(1, sizeof(struct aio_batch_entry));
-       BUG_ON(!aio_wq || !abe_pool);
+       BUG_ON(!aio_wq);
 
        pr_debug("aio_setup: sizeof(struct page) = %d\n", (int)sizeof(struct page));
 
@@ -1512,59 +1501,8 @@ static ssize_t aio_setup_iocb(struct kiocb *kiocb, bool compat)
        return 0;
 }
 
-static void aio_batch_add(struct address_space *mapping,
-                         struct hlist_head *batch_hash)
-{
-       struct aio_batch_entry *abe;
-       struct hlist_node *pos;
-       unsigned bucket;
-
-       bucket = hash_ptr(mapping, AIO_BATCH_HASH_BITS);
-       hlist_for_each_entry(abe, pos, &batch_hash[bucket], list) {
-               if (abe->mapping == mapping)
-                       return;
-       }
-
-       abe = mempool_alloc(abe_pool, GFP_KERNEL);
-
-       /*
-        * we should be using igrab here, but
-        * we don't want to hammer on the global
-        * inode spinlock just to take an extra
-        * reference on a file that we must already
-        * have a reference to.
-        *
-        * When we're called, we always have a reference
-        * on the file, so we must always have a reference
-        * on the inode, so ihold() is safe here.
-        */
-       ihold(mapping->host);
-       abe->mapping = mapping;
-       hlist_add_head(&abe->list, &batch_hash[bucket]);
-       return;
-}
-
-static void aio_batch_free(struct hlist_head *batch_hash)
-{
-       struct aio_batch_entry *abe;
-       struct hlist_node *pos, *n;
-       int i;
-
-       /*
-        * TODO: kill this
-        */
-       for (i = 0; i < AIO_BATCH_HASH_SIZE; i++) {
-               hlist_for_each_entry_safe(abe, pos, n, &batch_hash[i], list) {
-                       iput(abe->mapping->host);
-                       hlist_del(&abe->list);
-                       mempool_free(abe, abe_pool);
-               }
-       }
-}
-
 static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
-                        struct iocb *iocb, struct hlist_head *batch_hash,
-                        bool compat)
+                        struct iocb *iocb, bool compat)
 {
        struct kiocb *req;
        struct file *file;
@@ -1638,11 +1576,6 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
                        ;
        }
        spin_unlock_irq(&ctx->ctx_lock);
-       if (req->ki_opcode == IOCB_CMD_PREAD ||
-           req->ki_opcode == IOCB_CMD_PREADV ||
-           req->ki_opcode == IOCB_CMD_PWRITE ||
-           req->ki_opcode == IOCB_CMD_PWRITEV)
-               aio_batch_add(file->f_mapping, batch_hash);
 
        aio_put_req(req);       /* drop extra ref to req */
        return 0;
@@ -1659,7 +1592,6 @@ long do_io_submit(aio_context_t ctx_id, long nr,
        struct kioctx *ctx;
        long ret = 0;
        int i;
-       struct hlist_head batch_hash[AIO_BATCH_HASH_SIZE] = { { 0, }, };
        struct blk_plug plug;
 
        if (unlikely(nr < 0))
@@ -1697,12 +1629,11 @@ long do_io_submit(aio_context_t ctx_id, long nr,
                        break;
                }
 
-               ret = io_submit_one(ctx, user_iocb, &tmp, batch_hash, compat);
+               ret = io_submit_one(ctx, user_iocb, &tmp, compat);
                if (ret)
                        break;
        }
        blk_finish_plug(&plug);
-       aio_batch_free(batch_hash);
 
        put_ioctx(ctx);
        return i ? i : ret;