From: trondmy@kernel.org
To: linux-nfs@vger.kernel.org
Subject: [PATCH v10 06/26] NFS: Calculate page offsets algorithmically
Date: Sun, 13 Mar 2022 13:05:37 -0400 [thread overview]
Message-ID: <20220313170557.5940-7-trondmy@kernel.org> (raw)
In-Reply-To: <20220313170557.5940-6-trondmy@kernel.org>
From: Trond Myklebust <trond.myklebust@hammerspace.com>
Instead of relying on counting the page offsets as we walk through the
page cache, switch to calculating them algorithmically.
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
---
fs/nfs/dir.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c
index 379f88b158fb..6f0a38db6c37 100644
--- a/fs/nfs/dir.c
+++ b/fs/nfs/dir.c
@@ -249,17 +249,20 @@ static const char *nfs_readdir_copy_name(const char *name, unsigned int len)
return ret;
}
+static size_t nfs_readdir_array_maxentries(void)
+{
+ return (PAGE_SIZE - sizeof(struct nfs_cache_array)) /
+ sizeof(struct nfs_cache_array_entry);
+}
+
/*
* Check that the next array entry lies entirely within the page bounds
*/
static int nfs_readdir_array_can_expand(struct nfs_cache_array *array)
{
- struct nfs_cache_array_entry *cache_entry;
-
if (array->page_full)
return -ENOSPC;
- cache_entry = &array->array[array->size + 1];
- if ((char *)cache_entry - (char *)array > PAGE_SIZE) {
+ if (array->size == nfs_readdir_array_maxentries()) {
array->page_full = 1;
return -ENOSPC;
}
@@ -318,6 +321,11 @@ static struct page *nfs_readdir_page_get_locked(struct address_space *mapping,
return page;
}
+static loff_t nfs_readdir_page_offset(struct page *page)
+{
+ return (loff_t)page->index * (loff_t)nfs_readdir_array_maxentries();
+}
+
static u64 nfs_readdir_page_last_cookie(struct page *page)
{
struct nfs_cache_array *array;
@@ -448,7 +456,7 @@ static int nfs_readdir_search_for_cookie(struct nfs_cache_array *array,
if (array->array[i].cookie == desc->dir_cookie) {
struct nfs_inode *nfsi = NFS_I(file_inode(desc->file));
- new_pos = desc->current_index + i;
+ new_pos = nfs_readdir_page_offset(desc->page) + i;
if (desc->attr_gencount != nfsi->attr_gencount ||
!nfs_readdir_inode_mapping_valid(nfsi)) {
desc->duped = 0;
--
2.35.1
next prev parent reply other threads:[~2022-03-13 17:12 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-03-13 17:05 [PATCH v10 00/26] Readdir improvements trondmy
2022-03-13 17:05 ` [PATCH v10 01/26] NFS: Return valid errors from nfs2/3_decode_dirent() trondmy
2022-03-13 17:05 ` [PATCH v10 02/26] NFS: constify nfs_server_capable() and nfs_have_writebacks() trondmy
2022-03-13 17:05 ` [PATCH v10 03/26] NFS: Trace lookup revalidation failure trondmy
2022-03-13 17:05 ` [PATCH v10 04/26] NFS: Initialise the readdir verifier as best we can in nfs_opendir() trondmy
2022-03-13 17:05 ` [PATCH v10 05/26] NFS: Use kzalloc() to avoid initialising the nfs_open_dir_context trondmy
2022-03-13 17:05 ` trondmy [this message]
2022-03-13 17:05 ` [PATCH v10 07/26] NFS: Store the change attribute in the directory page cache trondmy
2022-03-13 17:05 ` [PATCH v10 08/26] NFS: Don't re-read the entire page cache to find the next cookie trondmy
2022-03-13 17:05 ` [PATCH v10 09/26] NFS: Don't advance the page pointer unless the page is full trondmy
2022-03-13 17:05 ` [PATCH v10 10/26] NFS: Adjust the amount of readahead performed by NFS readdir trondmy
2022-03-13 17:05 ` [PATCH v10 11/26] NFS: If the cookie verifier changes, we must invalidate the page cache trondmy
2022-03-13 17:05 ` [PATCH v10 12/26] NFS: Simplify nfs_readdir_xdr_to_array() trondmy
2022-03-13 17:05 ` [PATCH v10 13/26] NFS: Reduce use of uncached readdir trondmy
2022-03-13 17:05 ` [PATCH v10 14/26] NFS: Improve heuristic for readdirplus trondmy
2022-03-13 17:05 ` [PATCH v10 15/26] NFS: Don't ask for readdirplus unless it can help nfs_getattr() trondmy
2022-03-13 17:05 ` [PATCH v10 16/26] NFSv4: Ask for a full XDR buffer of readdir goodness trondmy
2022-03-13 17:05 ` [PATCH v10 17/26] NFS: Readdirplus can't help lookup for case insensitive filesystems trondmy
2022-03-13 17:05 ` [PATCH v10 18/26] NFS: Don't request readdirplus when revalidation was forced trondmy
2022-03-13 17:05 ` [PATCH v10 19/26] NFS: Add basic readdir tracing trondmy
2022-03-13 17:05 ` [PATCH v10 20/26] NFS: Trace effects of readdirplus on the dcache trondmy
2022-03-13 17:05 ` [PATCH v10 21/26] NFS: Trace effects of the readdirplus heuristic trondmy
2022-03-13 17:05 ` [PATCH v10 22/26] NFS: Clean up page array initialisation/free trondmy
2022-03-13 17:05 ` [PATCH v10 23/26] NFS: Convert readdir page cache to use a cookie based index trondmy
2022-03-13 17:05 ` [PATCH v10 24/26] NFS: Fix up forced readdirplus trondmy
2022-03-13 17:05 ` [PATCH v10 25/26] NFS: Optimise away the previous cookie field trondmy
2022-03-13 17:05 ` [PATCH v10 26/26] NFS: Cache all entries in the readdirplus reply trondmy
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