@@ -87,8 +87,7 @@ alloc_nfs_open_dir_context(struct inode *dir)
nfs_set_cache_invalid(dir,
NFS_INO_INVALID_DATA |
NFS_INO_REVAL_FORCED);
- list_add(&ctx->list, &nfsi->open_files);
- clear_bit(NFS_INO_FORCE_READDIR, &nfsi->flags);
+ list_add_tail_rcu(&ctx->list, &nfsi->open_files);
spin_unlock(&dir->i_lock);
return ctx;
}
@@ -98,9 +97,9 @@ alloc_nfs_open_dir_context(struct inode *dir)
static void put_nfs_open_dir_context(struct inode *dir, struct nfs_open_dir_context *ctx)
{
spin_lock(&dir->i_lock);
- list_del(&ctx->list);
+ list_del_rcu(&ctx->list);
spin_unlock(&dir->i_lock);
- kfree(ctx);
+ kfree_rcu(ctx, rcu_head);
}
/*
@@ -567,7 +566,6 @@ static int nfs_readdir_xdr_filler(struct nfs_readdir_descriptor *desc,
/* We requested READDIRPLUS, but the server doesn't grok it */
if (error == -ENOTSUPP && desc->plus) {
NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
- clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
desc->plus = arg.plus = false;
goto again;
}
@@ -617,51 +615,61 @@ int nfs_same_file(struct dentry *dentry, struct nfs_entry *entry)
return 1;
}
-static
-bool nfs_use_readdirplus(struct inode *dir, struct dir_context *ctx)
+#define NFS_READDIR_CACHE_USAGE_THRESHOLD (8UL)
+
+static bool nfs_use_readdirplus(struct inode *dir, struct dir_context *ctx,
+ unsigned int cache_hits,
+ unsigned int cache_misses)
{
if (!nfs_server_capable(dir, NFS_CAP_READDIRPLUS))
return false;
- if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(dir)->flags))
- return true;
- if (ctx->pos == 0)
+ if (ctx->pos == 0 ||
+ cache_hits + cache_misses > NFS_READDIR_CACHE_USAGE_THRESHOLD)
return true;
return false;
}
/*
- * This function is called by the lookup and getattr code to request the
+ * This function is called by the getattr code to request the
* use of readdirplus to accelerate any future lookups in the same
* directory.
*/
-void nfs_advise_use_readdirplus(struct inode *dir)
+void nfs_readdir_record_entry_cache_hit(struct inode *dir)
{
struct nfs_inode *nfsi = NFS_I(dir);
+ struct nfs_open_dir_context *ctx;
- if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS) &&
- !list_empty(&nfsi->open_files))
- set_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
+ if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS)) {
+ rcu_read_lock();
+ list_for_each_entry_rcu (ctx, &nfsi->open_files, list)
+ atomic_inc(&ctx->cache_hits);
+ rcu_read_unlock();
+ }
}
/*
* This function is mainly for use by nfs_getattr().
*
* If this is an 'ls -l', we want to force use of readdirplus.
- * Do this by checking if there is an active file descriptor
- * and calling nfs_advise_use_readdirplus, then forcing a
- * cache flush.
*/
-void nfs_force_use_readdirplus(struct inode *dir)
+void nfs_readdir_record_entry_cache_miss(struct inode *dir)
{
struct nfs_inode *nfsi = NFS_I(dir);
+ struct nfs_open_dir_context *ctx;
- if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS) &&
- !list_empty(&nfsi->open_files)) {
- set_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
- set_bit(NFS_INO_FORCE_READDIR, &nfsi->flags);
+ if (nfs_server_capable(dir, NFS_CAP_READDIRPLUS)) {
+ rcu_read_lock();
+ list_for_each_entry_rcu (ctx, &nfsi->open_files, list)
+ atomic_inc(&ctx->cache_misses);
+ rcu_read_unlock();
}
}
+static void nfs_lookup_advise_force_readdirplus(struct inode *dir)
+{
+ nfs_readdir_record_entry_cache_miss(dir);
+}
+
static
void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry,
unsigned long dir_verifier)
@@ -1101,6 +1109,20 @@ static int uncached_readdir(struct nfs_readdir_descriptor *desc)
return status;
}
+#define NFS_READDIR_CACHE_MISS_THRESHOLD (16UL)
+
+static void nfs_readdir_handle_cache_misses(struct inode *inode,
+ struct nfs_readdir_descriptor *desc,
+ pgoff_t page_index,
+ unsigned int cache_misses)
+{
+ if (desc->ctx->pos == 0 ||
+ cache_misses <= NFS_READDIR_CACHE_MISS_THRESHOLD ||
+ !nfs_readdir_may_fill_pagecache(desc))
+ return;
+ invalidate_mapping_pages(inode->i_mapping, page_index + 1, -1);
+}
+
/* The file offset position represents the dirent entry number. A
last cookie cache takes care of the common case of reading the
whole directory.
@@ -1112,6 +1134,7 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
struct nfs_inode *nfsi = NFS_I(inode);
struct nfs_open_dir_context *dir_ctx = file->private_data;
struct nfs_readdir_descriptor *desc;
+ unsigned int cache_hits, cache_misses;
pgoff_t page_index;
int res;
@@ -1137,7 +1160,6 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
goto out;
desc->file = file;
desc->ctx = ctx;
- desc->plus = nfs_use_readdirplus(inode, ctx);
desc->page_index_max = -1;
spin_lock(&file->f_lock);
@@ -1150,6 +1172,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
desc->page_fill_misses = dir_ctx->page_fill_misses;
nfs_set_dtsize(desc, dir_ctx->dtsize);
memcpy(desc->verf, dir_ctx->verf, sizeof(desc->verf));
+ cache_hits = atomic_xchg(&dir_ctx->cache_hits, 0);
+ cache_misses = atomic_xchg(&dir_ctx->cache_misses, 0);
spin_unlock(&file->f_lock);
if (desc->eof) {
@@ -1157,9 +1181,8 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
goto out_free;
}
- if (test_and_clear_bit(NFS_INO_FORCE_READDIR, &nfsi->flags) &&
- list_is_singular(&nfsi->open_files))
- invalidate_mapping_pages(inode->i_mapping, page_index + 1, -1);
+ desc->plus = nfs_use_readdirplus(inode, ctx, cache_hits, cache_misses);
+ nfs_readdir_handle_cache_misses(inode, desc, page_index, cache_misses);
do {
res = readdir_search_pagecache(desc);
@@ -1178,7 +1201,6 @@ static int nfs_readdir(struct file *file, struct dir_context *ctx)
break;
}
if (res == -ETOOSMALL && desc->plus) {
- clear_bit(NFS_INO_ADVISE_RDPLUS, &nfsi->flags);
nfs_zap_caches(inode);
desc->page_index = 0;
desc->plus = false;
@@ -1597,7 +1619,7 @@ nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry,
nfs_set_verifier(dentry, dir_verifier);
/* set a readdirplus hint that we had a cache miss */
- nfs_force_use_readdirplus(dir);
+ nfs_lookup_advise_force_readdirplus(dir);
ret = 1;
out:
nfs_free_fattr(fattr);
@@ -1654,7 +1676,6 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry,
nfs_mark_dir_for_revalidate(dir);
goto out_bad;
}
- nfs_advise_use_readdirplus(dir);
goto out_valid;
}
@@ -1859,7 +1880,7 @@ struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, unsigned in
goto out;
/* Notify readdir to use READDIRPLUS */
- nfs_force_use_readdirplus(dir);
+ nfs_lookup_advise_force_readdirplus(dir);
no_entry:
res = d_splice_alias(inode, dentry);
@@ -789,7 +789,7 @@ static void nfs_readdirplus_parent_cache_miss(struct dentry *dentry)
if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS))
return;
parent = dget_parent(dentry);
- nfs_force_use_readdirplus(d_inode(parent));
+ nfs_readdir_record_entry_cache_miss(d_inode(parent));
dput(parent);
}
@@ -800,7 +800,7 @@ static void nfs_readdirplus_parent_cache_hit(struct dentry *dentry)
if (!nfs_server_capable(d_inode(dentry), NFS_CAP_READDIRPLUS))
return;
parent = dget_parent(dentry);
- nfs_advise_use_readdirplus(d_inode(parent));
+ nfs_readdir_record_entry_cache_hit(d_inode(parent));
dput(parent);
}
@@ -366,8 +366,8 @@ extern struct nfs_client *nfs_init_client(struct nfs_client *clp,
const struct nfs_client_initdata *);
/* dir.c */
-extern void nfs_advise_use_readdirplus(struct inode *dir);
-extern void nfs_force_use_readdirplus(struct inode *dir);
+extern void nfs_readdir_record_entry_cache_hit(struct inode *dir);
+extern void nfs_readdir_record_entry_cache_miss(struct inode *dir);
extern unsigned long nfs_access_cache_count(struct shrinker *shrink,
struct shrink_control *sc);
extern unsigned long nfs_access_cache_scan(struct shrinker *shrink,
@@ -36,7 +36,6 @@
#define nfs_show_nfsi_flags(v) \
__print_flags(v, "|", \
- { BIT(NFS_INO_ADVISE_RDPLUS), "ADVISE_RDPLUS" }, \
{ BIT(NFS_INO_STALE), "STALE" }, \
{ BIT(NFS_INO_ACL_LRU_SET), "ACL_LRU_SET" }, \
{ BIT(NFS_INO_INVALIDATING), "INVALIDATING" }, \
@@ -101,6 +101,8 @@ struct nfs_open_context {
struct nfs_open_dir_context {
struct list_head list;
+ atomic_t cache_hits;
+ atomic_t cache_misses;
unsigned long attr_gencount;
__be32 verf[NFS_DIR_VERIFIER_SIZE];
__u64 dir_cookie;
@@ -110,6 +112,7 @@ struct nfs_open_dir_context {
unsigned int dtsize;
signed char duped;
bool eof;
+ struct rcu_head rcu_head;
};
/*
@@ -274,13 +277,11 @@ struct nfs4_copy_state {
/*
* Bit offsets in flags field
*/
-#define NFS_INO_ADVISE_RDPLUS (0) /* advise readdirplus */
#define NFS_INO_STALE (1) /* possible stale inode */
#define NFS_INO_ACL_LRU_SET (2) /* Inode is on the LRU list */
#define NFS_INO_INVALIDATING (3) /* inode is being invalidated */
#define NFS_INO_PRESERVE_UNLINKED (4) /* preserve file if removed while open */
#define NFS_INO_FSCACHE (5) /* inode can be cached by FS-Cache */
-#define NFS_INO_FORCE_READDIR (7) /* force readdirplus */
#define NFS_INO_LAYOUTCOMMIT (9) /* layoutcommit required */
#define NFS_INO_LAYOUTCOMMITTING (10) /* layoutcommit inflight */
#define NFS_INO_LAYOUTSTATS (11) /* layoutstats inflight */