freebsd-skq/sys/nfs/nfs_fha.h
ken 1ab8c6ab7f Move the NFS FHA (File Handle Affinity) code from sys/nfsserver to
sys/nfs, since it is now shared by the two NFS servers.

Suggested by:	rmacklem
Sponsored by:	Spectra Logic
MFC after:	2 weeks
2013-04-17 22:42:43 +00:00

113 lines
3.9 KiB
C

/*-
* Copyright (c) 2008 Isilon Inc http://www.isilon.com/
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/* $FreeBSD$ */
#ifndef _NFS_FHA_H
#define _NFS_FHA_H 1
#ifdef _KERNEL
/* Sysctl defaults. */
#define FHA_DEF_ENABLE 1
#define FHA_DEF_BIN_SHIFT 22 /* 4MB */
#define FHA_DEF_MAX_NFSDS_PER_FH 8
#define FHA_DEF_MAX_REQS_PER_NFSD 0 /* Unlimited */
/* This is the global structure that represents the state of the fha system. */
struct fha_global {
struct fha_hash_entry_list *hashtable;
u_long hashmask;
};
struct fha_ctls {
int enable;
uint32_t bin_shift;
uint32_t max_nfsds_per_fh;
uint32_t max_reqs_per_nfsd;
};
/*
* These are the entries in the filehandle hash. They talk about a specific
* file, requests against which are being handled by one or more nfsds. We
* keep a chain of nfsds against the file. We only have more than one if reads
* are ongoing, and then only if the reads affect disparate regions of the
* file.
*
* In general, we want to assign a new request to an existing nfsd if it is
* going to contend with work happening already on that nfsd, or if the
* operation is a read and the nfsd is already handling a proximate read. We
* do this to avoid jumping around in the read stream unnecessarily, and to
* avoid contention between threads over single files.
*/
struct fha_hash_entry {
LIST_ENTRY(fha_hash_entry) link;
u_int64_t fh;
u_int32_t num_rw;
u_int32_t num_exclusive;
u_int8_t num_threads;
struct svcthread_list threads;
};
LIST_HEAD(fha_hash_entry_list, fha_hash_entry);
/* A structure used for passing around data internally. */
struct fha_info {
u_int64_t fh;
off_t offset;
int locktype;
};
struct fha_callbacks {
rpcproc_t (*get_procnum)(rpcproc_t procnum);
int (*realign)(struct mbuf **mb, int malloc_flags);
int (*get_fh)(fhandle_t *fh, int v3, struct mbuf **md, caddr_t *dpos);
int (*is_read)(rpcproc_t procnum);
int (*is_write)(rpcproc_t procnum);
int (*get_offset)(struct mbuf **md, caddr_t *dpos, int v3, struct
fha_info *info);
int (*no_offset)(rpcproc_t procnum);
void (*set_locktype)(rpcproc_t procnum, struct fha_info *info);
int (*fhe_stats_sysctl)(SYSCTL_HANDLER_ARGS);
};
struct fha_params {
struct fha_global g_fha;
struct sysctl_ctx_list sysctl_ctx;
struct sysctl_oid *sysctl_tree;
struct fha_ctls ctls;
struct fha_callbacks callbacks;
char server_name[32];
SVCPOOL **pool;
};
void fha_nd_complete(SVCTHREAD *, struct svc_req *);
SVCTHREAD *fha_assign(SVCTHREAD *, struct svc_req *, struct fha_params *);
void fha_init(struct fha_params *softc);
void fha_uninit(struct fha_params *softc);
int fhe_stats_sysctl(SYSCTL_HANDLER_ARGS, struct fha_params *softc);
#endif /* _KERNEL */
#endif /* _NFS_FHA_H_ */