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Diffstat (limited to 'fs/nfs/write.c')
-rw-r--r--fs/nfs/write.c116
1 files changed, 74 insertions, 42 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c
index febdade9167..2867e6b7096 100644
--- a/fs/nfs/write.c
+++ b/fs/nfs/write.c
@@ -12,6 +12,7 @@
#include <linux/pagemap.h>
#include <linux/file.h>
#include <linux/writeback.h>
+#include <linux/swap.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs_fs.h>
@@ -38,7 +39,6 @@ static struct nfs_page * nfs_update_request(struct nfs_open_context*,
struct page *,
unsigned int, unsigned int);
static void nfs_mark_request_dirty(struct nfs_page *req);
-static int nfs_wait_on_write_congestion(struct address_space *, int);
static long nfs_flush_mapping(struct address_space *mapping, struct writeback_control *wbc, int how);
static const struct rpc_call_ops nfs_write_partial_ops;
static const struct rpc_call_ops nfs_write_full_ops;
@@ -48,8 +48,6 @@ static struct kmem_cache *nfs_wdata_cachep;
static mempool_t *nfs_wdata_mempool;
static mempool_t *nfs_commit_mempool;
-static DECLARE_WAIT_QUEUE_HEAD(nfs_write_congestion);
-
struct nfs_write_data *nfs_commit_alloc(void)
{
struct nfs_write_data *p = mempool_alloc(nfs_commit_mempool, GFP_NOFS);
@@ -211,6 +209,40 @@ static int wb_priority(struct writeback_control *wbc)
}
/*
+ * NFS congestion control
+ */
+
+int nfs_congestion_kb;
+
+#define NFS_CONGESTION_ON_THRESH (nfs_congestion_kb >> (PAGE_SHIFT-10))
+#define NFS_CONGESTION_OFF_THRESH \
+ (NFS_CONGESTION_ON_THRESH - (NFS_CONGESTION_ON_THRESH >> 2))
+
+static void nfs_set_page_writeback(struct page *page)
+{
+ if (!test_set_page_writeback(page)) {
+ struct inode *inode = page->mapping->host;
+ struct nfs_server *nfss = NFS_SERVER(inode);
+
+ if (atomic_inc_return(&nfss->writeback) >
+ NFS_CONGESTION_ON_THRESH)
+ set_bdi_congested(&nfss->backing_dev_info, WRITE);
+ }
+}
+
+static void nfs_end_page_writeback(struct page *page)
+{
+ struct inode *inode = page->mapping->host;
+ struct nfs_server *nfss = NFS_SERVER(inode);
+
+ end_page_writeback(page);
+ if (atomic_dec_return(&nfss->writeback) < NFS_CONGESTION_OFF_THRESH) {
+ clear_bdi_congested(&nfss->backing_dev_info, WRITE);
+ congestion_end(WRITE);
+ }
+}
+
+/*
* Find an associated nfs write request, and prepare to flush it out
* Returns 1 if there was no write request, or if the request was
* already tagged by nfs_set_page_dirty.Returns 0 if the request
@@ -247,7 +279,7 @@ static int nfs_page_mark_flush(struct page *page)
spin_unlock(req_lock);
if (test_and_set_bit(PG_FLUSHING, &req->wb_flags) == 0) {
nfs_mark_request_dirty(req);
- set_page_writeback(page);
+ nfs_set_page_writeback(page);
}
ret = test_bit(PG_NEED_FLUSH, &req->wb_flags);
nfs_unlock_request(req);
@@ -302,13 +334,8 @@ int nfs_writepage(struct page *page, struct writeback_control *wbc)
return err;
}
-/*
- * Note: causes nfs_update_request() to block on the assumption
- * that the writeback is generated due to memory pressure.
- */
int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
{
- struct backing_dev_info *bdi = mapping->backing_dev_info;
struct inode *inode = mapping->host;
int err;
@@ -317,20 +344,12 @@ int nfs_writepages(struct address_space *mapping, struct writeback_control *wbc)
err = generic_writepages(mapping, wbc);
if (err)
return err;
- while (test_and_set_bit(BDI_write_congested, &bdi->state) != 0) {
- if (wbc->nonblocking)
- return 0;
- nfs_wait_on_write_congestion(mapping, 0);
- }
err = nfs_flush_mapping(mapping, wbc, wb_priority(wbc));
if (err < 0)
goto out;
nfs_add_stats(inode, NFSIOS_WRITEPAGES, err);
err = 0;
out:
- clear_bit(BDI_write_congested, &bdi->state);
- wake_up_all(&nfs_write_congestion);
- congestion_end(WRITE);
return err;
}
@@ -360,7 +379,7 @@ static int nfs_inode_add_request(struct inode *inode, struct nfs_page *req)
}
/*
- * Insert a write request into an inode
+ * Remove a write request from an inode
*/
static void nfs_inode_remove_request(struct nfs_page *req)
{
@@ -531,10 +550,10 @@ static inline int nfs_scan_commit(struct inode *inode, struct list_head *dst, un
}
#endif
-static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
+static int nfs_wait_on_write_congestion(struct address_space *mapping)
{
+ struct inode *inode = mapping->host;
struct backing_dev_info *bdi = mapping->backing_dev_info;
- DEFINE_WAIT(wait);
int ret = 0;
might_sleep();
@@ -542,31 +561,23 @@ static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
if (!bdi_write_congested(bdi))
return 0;
- nfs_inc_stats(mapping->host, NFSIOS_CONGESTIONWAIT);
+ nfs_inc_stats(inode, NFSIOS_CONGESTIONWAIT);
- if (intr) {
- struct rpc_clnt *clnt = NFS_CLIENT(mapping->host);
+ do {
+ struct rpc_clnt *clnt = NFS_CLIENT(inode);
sigset_t oldset;
rpc_clnt_sigmask(clnt, &oldset);
- prepare_to_wait(&nfs_write_congestion, &wait, TASK_INTERRUPTIBLE);
- if (bdi_write_congested(bdi)) {
- if (signalled())
- ret = -ERESTARTSYS;
- else
- schedule();
- }
+ ret = congestion_wait_interruptible(WRITE, HZ/10);
rpc_clnt_sigunmask(clnt, &oldset);
- } else {
- prepare_to_wait(&nfs_write_congestion, &wait, TASK_UNINTERRUPTIBLE);
- if (bdi_write_congested(bdi))
- schedule();
- }
- finish_wait(&nfs_write_congestion, &wait);
+ if (ret == -ERESTARTSYS)
+ break;
+ ret = 0;
+ } while (bdi_write_congested(bdi));
+
return ret;
}
-
/*
* Try to update any existing write request, or create one if there is none.
* In order to match, the request's credentials must match those of
@@ -577,14 +588,15 @@ static int nfs_wait_on_write_congestion(struct address_space *mapping, int intr)
static struct nfs_page * nfs_update_request(struct nfs_open_context* ctx,
struct page *page, unsigned int offset, unsigned int bytes)
{
- struct inode *inode = page->mapping->host;
+ struct address_space *mapping = page->mapping;
+ struct inode *inode = mapping->host;
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_page *req, *new = NULL;
unsigned long rqend, end;
end = offset + bytes;
- if (nfs_wait_on_write_congestion(page->mapping, NFS_SERVER(inode)->flags & NFS_MOUNT_INTR))
+ if (nfs_wait_on_write_congestion(mapping))
return ERR_PTR(-ERESTARTSYS);
for (;;) {
/* Loop over all inode entries and see if we find
@@ -727,7 +739,7 @@ int nfs_updatepage(struct file *file, struct page *page,
static void nfs_writepage_release(struct nfs_page *req)
{
- end_page_writeback(req->wb_page);
+ nfs_end_page_writeback(req->wb_page);
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
if (!PageError(req->wb_page)) {
@@ -1042,12 +1054,12 @@ static void nfs_writeback_done_full(struct rpc_task *task, void *calldata)
if (task->tk_status < 0) {
nfs_set_pageerror(page);
req->wb_context->error = task->tk_status;
- end_page_writeback(page);
+ nfs_end_page_writeback(page);
nfs_inode_remove_request(req);
dprintk(", error = %d\n", task->tk_status);
goto next;
}
- end_page_writeback(page);
+ nfs_end_page_writeback(page);
#if defined(CONFIG_NFS_V3) || defined(CONFIG_NFS_V4)
if (data->args.stable != NFS_UNSTABLE || data->verf.committed == NFS_FILE_SYNC) {
@@ -1514,6 +1526,26 @@ int __init nfs_init_writepagecache(void)
if (nfs_commit_mempool == NULL)
return -ENOMEM;
+ /*
+ * NFS congestion size, scale with available memory.
+ *
+ * 64MB: 8192k
+ * 128MB: 11585k
+ * 256MB: 16384k
+ * 512MB: 23170k
+ * 1GB: 32768k
+ * 2GB: 46340k
+ * 4GB: 65536k
+ * 8GB: 92681k
+ * 16GB: 131072k
+ *
+ * This allows larger machines to have larger/more transfers.
+ * Limit the default to 256M
+ */
+ nfs_congestion_kb = (16*int_sqrt(totalram_pages)) << (PAGE_SHIFT-10);
+ if (nfs_congestion_kb > 256*1024)
+ nfs_congestion_kb = 256*1024;
+
return 0;
}