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* [PATCH 0/2] FlexFiles: too many bytes w/ direct+aio retried read
@ 2016-04-01 14:29 Weston Andros Adamson
  2016-04-01 14:29 ` [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs Weston Andros Adamson
  2016-04-01 14:29 ` [PATCH 2/2] nfs: add debug to directio "good_bytes" counting Weston Andros Adamson
  0 siblings, 2 replies; 5+ messages in thread
From: Weston Andros Adamson @ 2016-04-01 14:29 UTC (permalink / raw)
  To: trond.myklebust; +Cc: linux-nfs, Weston Andros Adamson

Patch 1 fixes an issue seen when using libaio with directio where if a read
is retried (ie due to recalled layout) we return too many bytes.
Specifically, we returned a multiple of the read size.

To reproduce, run fio with ioengine=libaio and direct=1, then revoke the
active layout. This should hit pretty easily.

Patch 2 should help notice similar issues elsewhere.

Weston Andros Adamson (2):
  pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs
  nfs: add debug to directio "good_bytes" counting

 fs/nfs/direct.c |  7 +++++--
 fs/nfs/pnfs.c   | 13 ++++++++-----
 fs/nfs/pnfs.h   |  2 +-
 3 files changed, 14 insertions(+), 8 deletions(-)

-- 
2.6.4 (Apple Git-63)


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs
  2016-04-01 14:29 [PATCH 0/2] FlexFiles: too many bytes w/ direct+aio retried read Weston Andros Adamson
@ 2016-04-01 14:29 ` Weston Andros Adamson
  2016-04-01 15:28   ` kbuild test robot
  2016-04-01 14:29 ` [PATCH 2/2] nfs: add debug to directio "good_bytes" counting Weston Andros Adamson
  1 sibling, 1 reply; 5+ messages in thread
From: Weston Andros Adamson @ 2016-04-01 14:29 UTC (permalink / raw)
  To: trond.myklebust; +Cc: linux-nfs, Weston Andros Adamson

Like other resend paths, mark the (old) hdr as NFS_IOHDR_REDO. This
ensures the hdr completion function will not count the (old) hdr
as good bytes.

Also, vector the error back through the hdr->task.tk_status like other
retry calls.

This fixes a bug with the FlexFiles layout where libaio was reporting more
bytes read than requested.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
---
 fs/nfs/pnfs.c | 13 ++++++++-----
 fs/nfs/pnfs.h |  2 +-
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index 2fa483e6dbe2..da90d665b01f 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -2143,12 +2143,15 @@ pnfs_try_to_read_data(struct nfs_pgio_header *hdr,
 }
 
 /* Resend all requests through pnfs. */
-int pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
+void pnfs_read_resend_pnfs(struct nfs_pgio_header *hdr)
 {
 	struct nfs_pageio_descriptor pgio;
 
-	nfs_pageio_init_read(&pgio, hdr->inode, false, hdr->completion_ops);
-	return nfs_pageio_resend(&pgio, hdr);
+	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
+		nfs_pageio_init_read(&pgio, hdr->inode, false,
+					hdr->completion_ops);
+		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
+	}
 }
 EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
 
@@ -2162,8 +2165,8 @@ pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
 
 	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
 	if (trypnfs == PNFS_TRY_AGAIN)
-		err = pnfs_read_resend_pnfs(hdr);
-	if (trypnfs == PNFS_NOT_ATTEMPTED || err)
+		pnfs_read_resend_pnfs(hdr);
+	if (trypnfs == PNFS_NOT_ATTEMPTED || hdr->task.tk_status)
 		pnfs_read_through_mds(desc, hdr);
 }
 
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 1ac1db5f6dad..7222d3a35439 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -282,7 +282,7 @@ int _pnfs_return_layout(struct inode *);
 int pnfs_commit_and_return_layout(struct inode *);
 void pnfs_ld_write_done(struct nfs_pgio_header *);
 void pnfs_ld_read_done(struct nfs_pgio_header *);
-int pnfs_read_resend_pnfs(struct nfs_pgio_header *);
+void pnfs_read_resend_pnfs(struct nfs_pgio_header *);
 struct pnfs_layout_segment *pnfs_update_layout(struct inode *ino,
 					       struct nfs_open_context *ctx,
 					       loff_t pos,
-- 
2.6.4 (Apple Git-63)


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 2/2] nfs: add debug to directio "good_bytes" counting
  2016-04-01 14:29 [PATCH 0/2] FlexFiles: too many bytes w/ direct+aio retried read Weston Andros Adamson
  2016-04-01 14:29 ` [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs Weston Andros Adamson
@ 2016-04-01 14:29 ` Weston Andros Adamson
  1 sibling, 0 replies; 5+ messages in thread
From: Weston Andros Adamson @ 2016-04-01 14:29 UTC (permalink / raw)
  To: trond.myklebust; +Cc: linux-nfs, Weston Andros Adamson

This will pop a warning if we count too many good bytes.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
---
 fs/nfs/direct.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 7a0cfd3266e5..5a31f2928530 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -87,6 +87,7 @@ struct nfs_direct_req {
 	int			mirror_count;
 
 	ssize_t			count,		/* bytes actually processed */
+				max_count,	/* max expected count */
 				bytes_left,	/* bytes left to be sent */
 				io_start,	/* start of IO */
 				error;		/* any reported error */
@@ -123,6 +124,8 @@ nfs_direct_good_bytes(struct nfs_direct_req *dreq, struct nfs_pgio_header *hdr)
 	int i;
 	ssize_t count;
 
+	WARN_ON_ONCE(dreq->count >= dreq->max_count);
+
 	if (dreq->mirror_count == 1) {
 		dreq->mirrors[hdr->pgio_mirror_idx].count += hdr->good_bytes;
 		dreq->count += hdr->good_bytes;
@@ -593,7 +596,7 @@ ssize_t nfs_file_direct_read(struct kiocb *iocb, struct iov_iter *iter,
 		goto out_unlock;
 
 	dreq->inode = inode;
-	dreq->bytes_left = count;
+	dreq->bytes_left = dreq->max_count = count;
 	dreq->io_start = pos;
 	dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp));
 	l_ctx = nfs_get_lock_context(dreq->ctx);
@@ -1026,7 +1029,7 @@ ssize_t nfs_file_direct_write(struct kiocb *iocb, struct iov_iter *iter)
 		goto out_unlock;
 
 	dreq->inode = inode;
-	dreq->bytes_left = iov_iter_count(iter);
+	dreq->bytes_left = dreq->max_count = iov_iter_count(iter);
 	dreq->io_start = pos;
 	dreq->ctx = get_nfs_open_context(nfs_file_open_context(iocb->ki_filp));
 	l_ctx = nfs_get_lock_context(dreq->ctx);
-- 
2.6.4 (Apple Git-63)


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs
  2016-04-01 14:29 ` [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs Weston Andros Adamson
@ 2016-04-01 15:28   ` kbuild test robot
  2016-04-01 15:43     ` Weston Andros Adamson
  0 siblings, 1 reply; 5+ messages in thread
From: kbuild test robot @ 2016-04-01 15:28 UTC (permalink / raw)
  To: Weston Andros Adamson
  Cc: kbuild-all, trond.myklebust, linux-nfs, Weston Andros Adamson

[-- Attachment #1: Type: text/plain, Size: 3071 bytes --]

Hi Weston,

[auto build test WARNING on v4.6-rc1]
[also build test WARNING on next-20160401]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url:    https://github.com/0day-ci/linux/commits/Weston-Andros-Adamson/pnfs-set-NFS_IOHDR_REDO-in-pnfs_read_resend_pnfs/20160401-223208
config: i386-allmodconfig (attached as .config)
reproduce:
        # save the attached .config to linux build tree
        make ARCH=i386 

All warnings (new ones prefixed by >>):

   fs/nfs/pnfs.c: In function 'pnfs_do_read':
>> fs/nfs/pnfs.c:2164:6: warning: unused variable 'err' [-Wunused-variable]
     int err = 0;
         ^

vim +/err +2164 fs/nfs/pnfs.c

ceb11e13 Peng Tao              2014-11-10  2148  	struct nfs_pageio_descriptor pgio;
ceb11e13 Peng Tao              2014-11-10  2149  
a5073dc2 Weston Andros Adamson 2016-04-01  2150  	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
a5073dc2 Weston Andros Adamson 2016-04-01  2151  		nfs_pageio_init_read(&pgio, hdr->inode, false,
a5073dc2 Weston Andros Adamson 2016-04-01  2152  					hdr->completion_ops);
a5073dc2 Weston Andros Adamson 2016-04-01  2153  		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
a5073dc2 Weston Andros Adamson 2016-04-01  2154  	}
ceb11e13 Peng Tao              2014-11-10  2155  }
ceb11e13 Peng Tao              2014-11-10  2156  EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
ceb11e13 Peng Tao              2014-11-10  2157  
493292dd Trond Myklebust       2011-07-13  2158  static void
7f714720 Weston Andros Adamson 2014-05-15  2159  pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
493292dd Trond Myklebust       2011-07-13  2160  {
493292dd Trond Myklebust       2011-07-13  2161  	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
493292dd Trond Myklebust       2011-07-13  2162  	struct pnfs_layout_segment *lseg = desc->pg_lseg;
493292dd Trond Myklebust       2011-07-13  2163  	enum pnfs_try_status trypnfs;
ceb11e13 Peng Tao              2014-11-10 @2164  	int err = 0;
493292dd Trond Myklebust       2011-07-13  2165  
d45f60c6 Weston Andros Adamson 2014-06-09  2166  	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
ceb11e13 Peng Tao              2014-11-10  2167  	if (trypnfs == PNFS_TRY_AGAIN)
a5073dc2 Weston Andros Adamson 2016-04-01  2168  		pnfs_read_resend_pnfs(hdr);
a5073dc2 Weston Andros Adamson 2016-04-01  2169  	if (trypnfs == PNFS_NOT_ATTEMPTED || hdr->task.tk_status)
d45f60c6 Weston Andros Adamson 2014-06-09  2170  		pnfs_read_through_mds(desc, hdr);
493292dd Trond Myklebust       2011-07-13  2171  }
493292dd Trond Myklebust       2011-07-13  2172  

:::::: The code at line 2164 was first introduced by commit
:::::: ceb11e13df3e78b450730c615037133c57b90c3b pnfs: allow LD to ask to resend read through pnfs

:::::: TO: Peng Tao <tao.peng@primarydata.com>
:::::: CC: Tom Haynes <loghyr@primarydata.com>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[-- Attachment #2: .config.gz --]
[-- Type: application/octet-stream, Size: 54415 bytes --]

^ permalink raw reply	[flat|nested] 5+ messages in thread

* Re: [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs
  2016-04-01 15:28   ` kbuild test robot
@ 2016-04-01 15:43     ` Weston Andros Adamson
  0 siblings, 0 replies; 5+ messages in thread
From: Weston Andros Adamson @ 2016-04-01 15:43 UTC (permalink / raw)
  To: kbuild test robot; +Cc: kbuild-all, Trond Myklebust, linux-nfs list


> On Apr 1, 2016, at 11:28 AM, kbuild test robot <lkp@intel.com> wrote:
> 
> Hi Weston,
> 
> [auto build test WARNING on v4.6-rc1]
> [also build test WARNING on next-20160401]
> [if your patch is applied to the wrong git tree, please drop us a note to help improving the system]
> 
> url:    https://github.com/0day-ci/linux/commits/Weston-Andros-Adamson/pnfs-set-NFS_IOHDR_REDO-in-pnfs_read_resend_pnfs/20160401-223208
> config: i386-allmodconfig (attached as .config)
> reproduce:
>        # save the attached .config to linux build tree
>        make ARCH=i386 
> 
> All warnings (new ones prefixed by >>):
> 
>   fs/nfs/pnfs.c: In function 'pnfs_do_read':
>>> fs/nfs/pnfs.c:2164:6: warning: unused variable 'err' [-Wunused-variable]
>     int err = 0;
>         ^

Thanks bot! Fixed and reposted.

-dros

> 
> vim +/err +2164 fs/nfs/pnfs.c
> 
> ceb11e13 Peng Tao              2014-11-10  2148  	struct nfs_pageio_descriptor pgio;
> ceb11e13 Peng Tao              2014-11-10  2149  
> a5073dc2 Weston Andros Adamson 2016-04-01  2150  	if (!test_and_set_bit(NFS_IOHDR_REDO, &hdr->flags)) {
> a5073dc2 Weston Andros Adamson 2016-04-01  2151  		nfs_pageio_init_read(&pgio, hdr->inode, false,
> a5073dc2 Weston Andros Adamson 2016-04-01  2152  					hdr->completion_ops);
> a5073dc2 Weston Andros Adamson 2016-04-01  2153  		hdr->task.tk_status = nfs_pageio_resend(&pgio, hdr);
> a5073dc2 Weston Andros Adamson 2016-04-01  2154  	}
> ceb11e13 Peng Tao              2014-11-10  2155  }
> ceb11e13 Peng Tao              2014-11-10  2156  EXPORT_SYMBOL_GPL(pnfs_read_resend_pnfs);
> ceb11e13 Peng Tao              2014-11-10  2157  
> 493292dd Trond Myklebust       2011-07-13  2158  static void
> 7f714720 Weston Andros Adamson 2014-05-15  2159  pnfs_do_read(struct nfs_pageio_descriptor *desc, struct nfs_pgio_header *hdr)
> 493292dd Trond Myklebust       2011-07-13  2160  {
> 493292dd Trond Myklebust       2011-07-13  2161  	const struct rpc_call_ops *call_ops = desc->pg_rpc_callops;
> 493292dd Trond Myklebust       2011-07-13  2162  	struct pnfs_layout_segment *lseg = desc->pg_lseg;
> 493292dd Trond Myklebust       2011-07-13  2163  	enum pnfs_try_status trypnfs;
> ceb11e13 Peng Tao              2014-11-10 @2164  	int err = 0;
> 493292dd Trond Myklebust       2011-07-13  2165  
> d45f60c6 Weston Andros Adamson 2014-06-09  2166  	trypnfs = pnfs_try_to_read_data(hdr, call_ops, lseg);
> ceb11e13 Peng Tao              2014-11-10  2167  	if (trypnfs == PNFS_TRY_AGAIN)
> a5073dc2 Weston Andros Adamson 2016-04-01  2168  		pnfs_read_resend_pnfs(hdr);
> a5073dc2 Weston Andros Adamson 2016-04-01  2169  	if (trypnfs == PNFS_NOT_ATTEMPTED || hdr->task.tk_status)
> d45f60c6 Weston Andros Adamson 2014-06-09  2170  		pnfs_read_through_mds(desc, hdr);
> 493292dd Trond Myklebust       2011-07-13  2171  }
> 493292dd Trond Myklebust       2011-07-13  2172  
> 
> :::::: The code at line 2164 was first introduced by commit
> :::::: ceb11e13df3e78b450730c615037133c57b90c3b pnfs: allow LD to ask to resend read through pnfs
> 
> :::::: TO: Peng Tao <tao.peng@primarydata.com>
> :::::: CC: Tom Haynes <loghyr@primarydata.com>
> 
> ---
> 0-DAY kernel test infrastructure                Open Source Technology Center
> https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
> <.config.gz>


^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2016-04-01 15:43 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-04-01 14:29 [PATCH 0/2] FlexFiles: too many bytes w/ direct+aio retried read Weston Andros Adamson
2016-04-01 14:29 ` [PATCH 1/2] pnfs: set NFS_IOHDR_REDO in pnfs_read_resend_pnfs Weston Andros Adamson
2016-04-01 15:28   ` kbuild test robot
2016-04-01 15:43     ` Weston Andros Adamson
2016-04-01 14:29 ` [PATCH 2/2] nfs: add debug to directio "good_bytes" counting Weston Andros Adamson

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