Revert "NFS: add nfs_sb_deactive_async to avoid deadlock"

This reverts commit 324d003b0c.

The deadlock turned out to be caused by a workqueue limitation that has
now been worked around in the RPC code (see comment in rpc_free_task).

Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This commit is contained in:
Trond Myklebust 2013-01-11 16:39:51 -05:00
parent 77102893ae
commit 322b2b9032
5 changed files with 3 additions and 56 deletions

View File

@ -694,10 +694,7 @@ static void __put_nfs_open_context(struct nfs_open_context *ctx, int is_sync)
if (ctx->cred != NULL)
put_rpccred(ctx->cred);
dput(ctx->dentry);
if (is_sync)
nfs_sb_deactive(sb);
else
nfs_sb_deactive_async(sb);
nfs_sb_deactive(sb);
kfree(ctx->mdsthreshold);
kfree(ctx);
}

View File

@ -329,7 +329,6 @@ extern int __init register_nfs_fs(void);
extern void __exit unregister_nfs_fs(void);
extern void nfs_sb_active(struct super_block *sb);
extern void nfs_sb_deactive(struct super_block *sb);
extern void nfs_sb_deactive_async(struct super_block *sb);
/* namespace.c */
#define NFS_PATH_CANONICAL 1

View File

@ -2088,7 +2088,7 @@ static void nfs4_free_closedata(void *data)
nfs4_put_open_state(calldata->state);
nfs_free_seqid(calldata->arg.seqid);
nfs4_put_state_owner(sp);
nfs_sb_deactive_async(sb);
nfs_sb_deactive(sb);
kfree(calldata);
}

View File

@ -54,7 +54,6 @@
#include <linux/parser.h>
#include <linux/nsproxy.h>
#include <linux/rcupdate.h>
#include <linux/kthread.h>
#include <asm/uaccess.h>
@ -418,54 +417,6 @@ void nfs_sb_deactive(struct super_block *sb)
}
EXPORT_SYMBOL_GPL(nfs_sb_deactive);
static int nfs_deactivate_super_async_work(void *ptr)
{
struct super_block *sb = ptr;
deactivate_super(sb);
module_put_and_exit(0);
return 0;
}
/*
* same effect as deactivate_super, but will do final unmount in kthread
* context
*/
static void nfs_deactivate_super_async(struct super_block *sb)
{
struct task_struct *task;
char buf[INET6_ADDRSTRLEN + 1];
struct nfs_server *server = NFS_SB(sb);
struct nfs_client *clp = server->nfs_client;
if (!atomic_add_unless(&sb->s_active, -1, 1)) {
rcu_read_lock();
snprintf(buf, sizeof(buf),
rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_ADDR));
rcu_read_unlock();
__module_get(THIS_MODULE);
task = kthread_run(nfs_deactivate_super_async_work, sb,
"%s-deactivate-super", buf);
if (IS_ERR(task)) {
pr_err("%s: kthread_run: %ld\n",
__func__, PTR_ERR(task));
/* make synchronous call and hope for the best */
deactivate_super(sb);
module_put(THIS_MODULE);
}
}
}
void nfs_sb_deactive_async(struct super_block *sb)
{
struct nfs_server *server = NFS_SB(sb);
if (atomic_dec_and_test(&server->active))
nfs_deactivate_super_async(sb);
}
EXPORT_SYMBOL_GPL(nfs_sb_deactive_async);
/*
* Deliver file system statistics to userspace
*/

View File

@ -95,7 +95,7 @@ static void nfs_async_unlink_release(void *calldata)
nfs_dec_sillycount(data->dir);
nfs_free_unlinkdata(data);
nfs_sb_deactive_async(sb);
nfs_sb_deactive(sb);
}
static void nfs_unlink_prepare(struct rpc_task *task, void *calldata)