From c23fbb6bcb3eb9cdf39a103edadf57bde8ce309c Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 8 May 2007 00:26:18 -0700 Subject: VFS: delay the dentry name generation on sockets and pipes 1) Introduces a new method in 'struct dentry_operations'. This method called d_dname() might be called from d_path() to build a pathname for special filesystems. It is called without locks. Future patches (if we succeed in having one common dentry for all pipes/sockets) may need to change prototype of this method, but we now use : char *d_dname(struct dentry *dentry, char *buffer, int buflen); 2) Adds a dynamic_dname() helper function that eases d_dname() implementations 3) Defines d_dname method for sockets : No more sprintf() at socket creation. This is delayed up to the moment someone does an access to /proc/pid/fd/... 4) Defines d_dname method for pipes : No more sprintf() at pipe creation. This is delayed up to the moment someone does an access to /proc/pid/fd/... A benchmark consisting of 1.000.000 calls to pipe()/close()/close() gives a *nice* speedup on my Pentium(M) 1.6 Ghz : 3.090 s instead of 3.450 s Signed-off-by: Eric Dumazet Acked-by: Christoph Hellwig Acked-by: Linus Torvalds Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/dcache.h | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'include/linux') diff --git a/include/linux/dcache.h b/include/linux/dcache.h index 63f64a9a5bf7..aab53df4fafa 100644 --- a/include/linux/dcache.h +++ b/include/linux/dcache.h @@ -133,6 +133,7 @@ struct dentry_operations { int (*d_delete)(struct dentry *); void (*d_release)(struct dentry *); void (*d_iput)(struct dentry *, struct inode *); + char *(*d_dname)(struct dentry *, char *, int); }; /* the dentry parameter passed to d_hash and d_compare is the parent @@ -293,6 +294,11 @@ extern struct dentry * d_hash_and_lookup(struct dentry *, struct qstr *); /* validate "insecure" dentry pointer */ extern int d_validate(struct dentry *, struct dentry *); +/* + * helper function for dentry_operations.d_dname() members + */ +extern char *dynamic_dname(struct dentry *, char *, int, const char *, ...); + extern char * d_path(struct dentry *, struct vfsmount *, char *, int); /* Allocation counts.. */ -- cgit v1.2.2