From: Fred Isaman <iisaman@xxxxxxxxxx>
Add a pg_test layout driver hook which is used to avoid coelescing I/O across
layout stripes.
Signed-off-by: Andy Adamon <andros@xxxxxxxxxx>
Signed-off-by: Andy Adamon <andros@xxxxxxxxxxxxxx>
Signed-off-by: Dean Hildebrand <dhildeb@xxxxxxxxxx>
Signed-off-by: Fred Isaman <iisaman@xxxxxxxxxxxxxx>
Signed-off-by: Fred Isaman <iisaman@xxxxxxxxxx>
Signed-off-by: Benny Halevy <bhalevy@xxxxxxxxxxx>
Signed-off-by: Boaz Harrosh <bharrosh@xxxxxxxxxxx>
Signed-off-by: Oleg Drokin <green@xxxxxxxxxxxxxx>
Signed-off-by: Tao Guo <guotao@xxxxxxxxxxxx>
---
fs/nfs/nfs4filelayout.c | 26 ++++++++++++++++++++++++++
fs/nfs/pagelist.c | 18 +++++++++++++-----
fs/nfs/pnfs.c | 19 +++++++++++++++++++
fs/nfs/pnfs.h | 12 ++++++++++++
fs/nfs/read.c | 1 +
fs/nfs/write.c | 3 +++
include/linux/nfs_page.h | 1 +
7 files changed, 75 insertions(+), 5 deletions(-)
diff --git a/fs/nfs/nfs4filelayout.c b/fs/nfs/nfs4filelayout.c
index 23f930c..98e26e0 100644
--- a/fs/nfs/nfs4filelayout.c
+++ b/fs/nfs/nfs4filelayout.c
@@ -252,6 +252,31 @@ filelayout_free_lseg(struct pnfs_layout_segment *lseg)
_filelayout_free_lseg(fl);
}
+/*
+ * filelayout_pg_test(). Called by nfs_can_coalesce_requests()
+ *
+ * return 1 : coalesce page
+ * return 0 : don't coalesce page
+ */
+int
+filelayout_pg_test(struct nfs_pageio_descriptor *pgio, struct nfs_page *prev,
+ struct nfs_page *req)
+{
+ u64 p_stripe, r_stripe;
+ u32 stripe_unit;
+
+ if (!pgio->pg_lseg)
+ return 1;
+ p_stripe = (u64)prev->wb_index << PAGE_CACHE_SHIFT;
+ r_stripe = (u64)req->wb_index << PAGE_CACHE_SHIFT;
+ stripe_unit = FILELAYOUT_LSEG(pgio->pg_lseg)->stripe_unit;
+
+ do_div(p_stripe, stripe_unit);
+ do_div(r_stripe, stripe_unit);
+
+ return (p_stripe == r_stripe);
+}
+
static struct pnfs_layoutdriver_type filelayout_type = {
.id = LAYOUT_NFSV4_1_FILES,
.name = "LAYOUT_NFSV4_1_FILES",
@@ -260,6 +285,7 @@ static struct pnfs_layoutdriver_type filelayout_type = {
.clear_layoutdriver = filelayout_clear_layoutdriver,
.alloc_lseg = filelayout_alloc_lseg,
.free_lseg = filelayout_free_lseg,
+ .pg_test = filelayout_pg_test,
};
static int __init nfs4filelayout_init(void)
diff --git a/fs/nfs/pagelist.c b/fs/nfs/pagelist.c
index e0a0cb4..2c793a7 100644
--- a/fs/nfs/pagelist.c
+++ b/fs/nfs/pagelist.c
@@ -242,7 +242,8 @@ void nfs_pageio_init(struct nfs_pageio_descriptor *desc,
* Return 'true' if this is the case, else return 'false'.
*/
static int nfs_can_coalesce_requests(struct nfs_page *prev,
- struct nfs_page *req)
+ struct nfs_page *req,
+ struct nfs_pageio_descriptor *pgio)
{
if (req->wb_context->cred != prev->wb_context->cred)
return 0;
@@ -256,6 +257,12 @@ static int nfs_can_coalesce_requests(struct nfs_page *prev,
return 0;
if (prev->wb_pgbase + prev->wb_bytes != PAGE_CACHE_SIZE)
return 0;
+ /*
+ * Non-whole file layouts need to check that req is inside of
+ * pgio->pg_lseg.
+ */
+ if (pgio->pg_test && !pgio->pg_test(pgio, prev, req))
+ return 0;
return 1;
}
@@ -288,14 +295,15 @@ static int nfs_pageio_do_add_request(struct nfs_pageio_descriptor *desc,
if (newlen > desc->pg_bsize)
return 0;
prev = nfs_list_entry(desc->pg_list.prev);
- if (!nfs_can_coalesce_requests(prev, req))
+ if (!nfs_can_coalesce_requests(prev, req, desc))
return 0;
} else {
put_lseg(desc->pg_lseg);
desc->pg_base = req->wb_pgbase;
- desc->pg_lseg = pnfs_update_layout(desc->pg_inode,
- req->wb_context,
- IOMODE_READ);
+ if (desc->pg_test)
+ desc->pg_lseg = pnfs_update_layout(desc->pg_inode,
+ req->wb_context,
+ IOMODE_READ);
}
nfs_list_remove_request(req);
nfs_list_add_request(req, &desc->pg_list);
diff --git a/fs/nfs/pnfs.c b/fs/nfs/pnfs.c
index dcd4356..f200e34 100644
--- a/fs/nfs/pnfs.c
+++ b/fs/nfs/pnfs.c
@@ -871,6 +871,25 @@ out_forget_reply:
goto out;
}
+static void
+pnfs_set_pg_test(struct inode *inode, struct nfs_pageio_descriptor *pgio)
+{
+ struct pnfs_layoutdriver_type *ld;
+
+ ld = NFS_SERVER(inode)->pnfs_curr_ld;
+ pgio->pg_test = (ld ? ld->pg_test : NULL);
+}
+
+/*
+ * rsize is already set by caller to MDS rsize.
+ */
+void
+pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio,
+ struct inode *inode)
+{
+ pnfs_set_pg_test(inode, pgio);
+}
+
/*
* Device ID cache. Currently supports one layout type per struct nfs_client.
* Add layout type to the lookup key to expand to support multiple types.
diff --git a/fs/nfs/pnfs.h b/fs/nfs/pnfs.h
index 121d6a3..5107d14 100644
--- a/fs/nfs/pnfs.h
+++ b/fs/nfs/pnfs.h
@@ -30,6 +30,8 @@
#ifndef FS_NFS_PNFS_H
#define FS_NFS_PNFS_H
+#include <linux/nfs_page.h>
+
enum {
NFS_LSEG_VALID = 0, /* cleared when lseg is recalled/returned */
NFS_LSEG_ROC, /* roc bit received from server */
@@ -65,6 +67,9 @@ struct pnfs_layoutdriver_type {
int (*clear_layoutdriver) (struct nfs_server *);
struct pnfs_layout_segment * (*alloc_lseg) (struct pnfs_layout_hdr *layoutid, struct nfs4_layoutget_res *lgr);
void (*free_lseg) (struct pnfs_layout_segment *lseg);
+
+ /* test for nfs page cache coalescing */
+ int (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
};
struct pnfs_layout_hdr {
@@ -152,6 +157,7 @@ pnfs_update_layout(struct inode *ino, struct nfs_open_context *ctx,
enum pnfs_iomode access_type);
void set_pnfs_layoutdriver(struct nfs_server *, u32 id);
void unset_pnfs_layoutdriver(struct nfs_server *);
+void pnfs_pageio_init_read(struct nfs_pageio_descriptor *, struct inode *);
int pnfs_layout_process(struct nfs4_layoutget *lgp);
void pnfs_free_lseg_list(struct list_head *tmp_list);
void pnfs_destroy_layout(struct nfs_inode *);
@@ -251,6 +257,12 @@ static inline void unset_pnfs_layoutdriver(struct nfs_server *s)
{
}
+static inline void
+pnfs_pageio_init_read(struct nfs_pageio_descriptor *pgio, struct inode *ino)
+{
+ pgio->pg_test = NULL;
+}
+
#endif /* CONFIG_NFS_V4_1 */
#endif /* FS_NFS_PNFS_H */
diff --git a/fs/nfs/read.c b/fs/nfs/read.c
index c453164..20cc936 100644
--- a/fs/nfs/read.c
+++ b/fs/nfs/read.c
@@ -630,6 +630,7 @@ int nfs_readpages(struct file *filp, struct address_space *mapping,
if (ret == 0)
goto read_complete; /* all pages were read */
+ pnfs_pageio_init_read(&pgio, inode);
if (rsize < PAGE_CACHE_SIZE)
nfs_pageio_init(&pgio, inode, nfs_pagein_multi, rsize, 0);
else
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index 004c28b..aca0268 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -28,6 +28,7 @@
#include "iostat.h"
#include "nfs4_fs.h"
#include "fscache.h"
+#include "pnfs.h"
#define NFSDBG_FACILITY NFSDBG_PAGECACHE
@@ -982,6 +983,8 @@ static void nfs_pageio_init_write(struct nfs_pageio_descriptor *pgio,
{
size_t wsize = NFS_SERVER(inode)->wsize;
+ pgio->pg_test = NULL;
+
if (wsize < PAGE_CACHE_SIZE)
nfs_pageio_init(pgio, inode, nfs_flush_multi, wsize, ioflags);
else
diff --git a/include/linux/nfs_page.h b/include/linux/nfs_page.h
index 2db0372..ba88ff4 100644
--- a/include/linux/nfs_page.h
+++ b/include/linux/nfs_page.h
@@ -63,6 +63,7 @@ struct nfs_pageio_descriptor {
int pg_ioflags;
int pg_error;
struct pnfs_layout_segment *pg_lseg;
+ int (*pg_test)(struct nfs_pageio_descriptor *, struct nfs_page *, struct nfs_page *);
};
#define NFS_WBACK_BUSY(req) (test_bit(PG_BUSY,&(req)->wb_flags))
--
1.7.2.3
--
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