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-rw-r--r--sys/nfsserver/nfs_fha.c597
1 files changed, 597 insertions, 0 deletions
diff --git a/sys/nfsserver/nfs_fha.c b/sys/nfsserver/nfs_fha.c
new file mode 100644
index 0000000..a2e4ca3
--- /dev/null
+++ b/sys/nfsserver/nfs_fha.c
@@ -0,0 +1,597 @@
+/*-
+ * 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.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <sys/param.h>
+#include <sys/systm.h>
+#include <sys/sysproto.h>
+#include <sys/kernel.h>
+#include <sys/sysctl.h>
+#include <sys/vnode.h>
+#include <sys/malloc.h>
+#include <sys/mount.h>
+#include <sys/mbuf.h>
+#include <sys/sbuf.h>
+
+#include <rpc/rpc.h>
+#include <nfs/xdr_subs.h>
+#include <nfs/rpcv2.h>
+#include <nfs/nfsproto.h>
+#include <nfsserver/nfs.h>
+#include <nfsserver/nfsm_subs.h>
+#include <nfsserver/nfs_fha.h>
+
+#ifndef NFS_LEGACYRPC
+
+static MALLOC_DEFINE(M_NFS_FHA, "NFS FHA", "NFS FHA");
+
+/* Sysctl defaults. */
+#define DEF_BIN_SHIFT 18 /* 256k */
+#define DEF_MAX_NFSDS_PER_FH 8
+#define DEF_MAX_REQS_PER_NFSD 4
+
+struct fha_ctls {
+ u_int32_t bin_shift;
+ u_int32_t max_nfsds_per_fh;
+ u_int32_t max_reqs_per_nfsd;
+} fha_ctls;
+
+struct sysctl_ctx_list fha_clist;
+
+SYSCTL_DECL(_vfs_nfsrv);
+SYSCTL_DECL(_vfs_nfsrv_fha);
+
+/* Static sysctl node for the fha from the top-level vfs_nfsrv node. */
+SYSCTL_NODE(_vfs_nfsrv, OID_AUTO, fha, CTLFLAG_RD, 0, "fha node");
+
+/* This is the global structure that represents the state of the fha system. */
+static struct fha_global {
+ struct fha_hash_entry_list *hashtable;
+ u_long hashmask;
+} g_fha;
+
+/*
+ * 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_int16_t num_reads;
+ u_int16_t num_writes;
+ 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;
+};
+
+static int fhe_stats_sysctl(SYSCTL_HANDLER_ARGS);
+
+static void
+nfs_fha_init(void *foo)
+{
+
+ /*
+ * A small hash table to map filehandles to fha_hash_entry
+ * structures.
+ */
+ g_fha.hashtable = hashinit(256, M_NFS_FHA, &g_fha.hashmask);
+
+ /*
+ * Initialize the sysctl context list for the fha module.
+ */
+ sysctl_ctx_init(&fha_clist);
+
+ fha_ctls.bin_shift = DEF_BIN_SHIFT;
+ fha_ctls.max_nfsds_per_fh = DEF_MAX_NFSDS_PER_FH;
+ fha_ctls.max_reqs_per_nfsd = DEF_MAX_REQS_PER_NFSD;
+
+ SYSCTL_ADD_UINT(&fha_clist, SYSCTL_STATIC_CHILDREN(_vfs_nfsrv_fha),
+ OID_AUTO, "bin_shift", CTLFLAG_RW,
+ &fha_ctls.bin_shift, 0, "For FHA reads, no two requests will "
+ "contend if they're 2^(bin_shift) bytes apart");
+
+ SYSCTL_ADD_UINT(&fha_clist, SYSCTL_STATIC_CHILDREN(_vfs_nfsrv_fha),
+ OID_AUTO, "max_nfsds_per_fh", CTLFLAG_RW,
+ &fha_ctls.max_nfsds_per_fh, 0, "Maximum nfsd threads that "
+ "should be working on requests for the same file handle");
+
+ SYSCTL_ADD_UINT(&fha_clist, SYSCTL_STATIC_CHILDREN(_vfs_nfsrv_fha),
+ OID_AUTO, "max_reqs_per_nfsd", CTLFLAG_RW,
+ &fha_ctls.max_reqs_per_nfsd, 0, "Maximum requests that "
+ "single nfsd thread should be working on at any time");
+
+ SYSCTL_ADD_OID(&fha_clist, SYSCTL_STATIC_CHILDREN(_vfs_nfsrv_fha),
+ OID_AUTO, "fhe_stats", CTLTYPE_STRING | CTLFLAG_RD, 0, 0,
+ fhe_stats_sysctl, "A", "");
+}
+
+static void
+nfs_fha_uninit(void *foo)
+{
+
+ hashdestroy(g_fha.hashtable, M_NFS_FHA, g_fha.hashmask);
+}
+
+SYSINIT(nfs_fha, SI_SUB_ROOT_CONF, SI_ORDER_ANY, nfs_fha_init, NULL);
+SYSUNINIT(nfs_fha, SI_SUB_ROOT_CONF, SI_ORDER_ANY, nfs_fha_uninit, NULL);
+
+/*
+ * This just specifies that offsets should obey affinity when within
+ * the same 1Mbyte (1<<20) chunk for the file (reads only for now).
+ */
+static void
+fha_extract_info(struct svc_req *req, struct fha_info *i)
+{
+ struct mbuf *md = req->rq_args;
+ fhandle_t fh;
+ caddr_t dpos = mtod(md, caddr_t);
+ static u_int64_t random_fh = 0;
+ int error;
+ int v3 = (req->rq_vers == 3);
+ u_int32_t *tl;
+ rpcproc_t procnum;
+
+ /*
+ * We start off with a random fh. If we get a reasonable
+ * procnum, we set the fh. If there's a concept of offset
+ * that we're interested in, we set that.
+ */
+ i->fh = ++random_fh;
+ i->offset = 0;
+ i->locktype = LK_EXCLUSIVE;
+
+ /*
+ * Extract the procnum and convert to v3 form if necessary.
+ */
+ procnum = req->rq_proc;
+ if (!v3)
+ procnum = nfsrv_nfsv3_procid[procnum];
+
+ /*
+ * We do affinity for most. However, we divide a realm of affinity
+ * by file offset so as to allow for concurrent random access. We
+ * only do this for reads today, but this may change when IFS supports
+ * efficient concurrent writes.
+ */
+ if (procnum == NFSPROC_FSSTAT ||
+ procnum == NFSPROC_FSINFO ||
+ procnum == NFSPROC_PATHCONF ||
+ procnum == NFSPROC_NOOP ||
+ procnum == NFSPROC_NULL)
+ goto out;
+
+ /* Grab the filehandle. */
+ error = nfsm_srvmtofh_xx(&fh, v3, &md, &dpos);
+ if (error)
+ goto out;
+
+ i->fh = *(const u_int64_t *)(fh.fh_fid.fid_data);
+
+ /* Content ourselves with zero offset for all but reads. */
+ if (procnum != NFSPROC_READ)
+ goto out;
+
+ if (v3) {
+ tl = nfsm_dissect_xx_nonblock(2 * NFSX_UNSIGNED, &md, &dpos);
+ if (tl == NULL)
+ goto out;
+ i->offset = fxdr_hyper(tl);
+ } else {
+ tl = nfsm_dissect_xx_nonblock(NFSX_UNSIGNED, &md, &dpos);
+ if (tl == NULL)
+ goto out;
+ i->offset = fxdr_unsigned(u_int32_t, *tl);
+ }
+ out:
+ switch (procnum) {
+ case NFSPROC_NULL:
+ case NFSPROC_GETATTR:
+ case NFSPROC_LOOKUP:
+ case NFSPROC_ACCESS:
+ case NFSPROC_READLINK:
+ case NFSPROC_READ:
+ case NFSPROC_READDIR:
+ case NFSPROC_READDIRPLUS:
+ i->locktype = LK_SHARED;
+ break;
+ case NFSPROC_SETATTR:
+ case NFSPROC_WRITE:
+ case NFSPROC_CREATE:
+ case NFSPROC_MKDIR:
+ case NFSPROC_SYMLINK:
+ case NFSPROC_MKNOD:
+ case NFSPROC_REMOVE:
+ case NFSPROC_RMDIR:
+ case NFSPROC_RENAME:
+ case NFSPROC_LINK:
+ case NFSPROC_FSSTAT:
+ case NFSPROC_FSINFO:
+ case NFSPROC_PATHCONF:
+ case NFSPROC_COMMIT:
+ case NFSPROC_NOOP:
+ i->locktype = LK_EXCLUSIVE;
+ break;
+ }
+}
+
+static struct fha_hash_entry *
+fha_hash_entry_new(u_int64_t fh)
+{
+ struct fha_hash_entry *e;
+
+ e = malloc(sizeof(*e), M_NFS_FHA, M_WAITOK);
+ e->fh = fh;
+ e->num_reads = 0;
+ e->num_writes = 0;
+ e->num_threads = 0;
+ LIST_INIT(&e->threads);
+
+ return e;
+}
+
+static void
+fha_hash_entry_destroy(struct fha_hash_entry *e)
+{
+
+ if (e->num_reads + e->num_writes)
+ panic("nonempty fhe");
+ free(e, M_NFS_FHA);
+}
+
+static void
+fha_hash_entry_remove(struct fha_hash_entry *e)
+{
+
+ LIST_REMOVE(e, link);
+ fha_hash_entry_destroy(e);
+}
+
+static struct fha_hash_entry *
+fha_hash_entry_lookup(SVCPOOL *pool, u_int64_t fh)
+{
+ struct fha_hash_entry *fhe, *new_fhe;
+
+ LIST_FOREACH(fhe, &g_fha.hashtable[fh % g_fha.hashmask], link) {
+ if (fhe->fh == fh)
+ break;
+ }
+
+ if (!fhe) {
+ /* Allocate a new entry. */
+ mtx_unlock(&pool->sp_lock);
+ new_fhe = fha_hash_entry_new(fh);
+ mtx_lock(&pool->sp_lock);
+
+ /* Double-check to make sure we still need the new entry. */
+ LIST_FOREACH(fhe, &g_fha.hashtable[fh % g_fha.hashmask], link) {
+ if (fhe->fh == fh)
+ break;
+ }
+ if (!fhe) {
+ fhe = new_fhe;
+ LIST_INSERT_HEAD(&g_fha.hashtable[fh % g_fha.hashmask],
+ fhe, link);
+ } else {
+ fha_hash_entry_destroy(new_fhe);
+ }
+ }
+
+ return fhe;
+}
+
+static void
+fha_hash_entry_add_thread(struct fha_hash_entry *fhe, SVCTHREAD *thread)
+{
+ LIST_INSERT_HEAD(&fhe->threads, thread, st_alink);
+ fhe->num_threads++;
+}
+
+static void
+fha_hash_entry_remove_thread(struct fha_hash_entry *fhe, SVCTHREAD *thread)
+{
+
+ LIST_REMOVE(thread, st_alink);
+ fhe->num_threads--;
+}
+
+/*
+ * Account for an ongoing operation associated with this file.
+ */
+static void
+fha_hash_entry_add_op(struct fha_hash_entry *fhe, int locktype, int count)
+{
+
+ if (LK_EXCLUSIVE == locktype)
+ fhe->num_writes += count;
+ else
+ fhe->num_reads += count;
+}
+
+static SVCTHREAD *
+get_idle_thread(SVCPOOL *pool)
+{
+ SVCTHREAD *st;
+
+ LIST_FOREACH(st, &pool->sp_idlethreads, st_ilink) {
+ if (st->st_xprt == NULL && STAILQ_EMPTY(&st->st_reqs))
+ return (st);
+ }
+ return (NULL);
+}
+
+
+/*
+ * Get the service thread currently associated with the fhe that is
+ * appropriate to handle this operation.
+ */
+SVCTHREAD *
+fha_hash_entry_choose_thread(SVCPOOL *pool, struct fha_hash_entry *fhe,
+ struct fha_info *i, SVCTHREAD *this_thread);
+
+SVCTHREAD *
+fha_hash_entry_choose_thread(SVCPOOL *pool, struct fha_hash_entry *fhe,
+ struct fha_info *i, SVCTHREAD *this_thread)
+{
+ SVCTHREAD *thread, *min_thread = NULL;
+ int req_count, min_count = 0;
+ off_t offset1, offset2;
+
+ LIST_FOREACH(thread, &fhe->threads, st_alink) {
+ req_count = thread->st_reqcount;
+
+ /* If there are any writes in progress, use the first thread. */
+ if (fhe->num_writes) {
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)w", thread, req_count);
+#endif
+ return (thread);
+ }
+
+ /*
+ * Check for read locality, making sure that we won't
+ * exceed our per-thread load limit in the process.
+ */
+ offset1 = i->offset >> fha_ctls.bin_shift;
+ offset2 = STAILQ_FIRST(&thread->st_reqs)->rq_p3
+ >> fha_ctls.bin_shift;
+ if (offset1 == offset2) {
+ if ((fha_ctls.max_reqs_per_nfsd == 0) ||
+ (req_count < fha_ctls.max_reqs_per_nfsd)) {
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)r", thread, req_count);
+#endif
+ return (thread);
+ }
+ }
+
+ /*
+ * We don't have a locality match, so skip this thread,
+ * but keep track of the most attractive thread in case
+ * we need to come back to it later.
+ */
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)s off1 %llu off2 %llu", thread,
+ req_count, offset1, offset2);
+#endif
+ if ((min_thread == NULL) || (req_count < min_count)) {
+ min_count = req_count;
+ min_thread = thread;
+ }
+ }
+
+ /*
+ * We didn't find a good match yet. See if we can add
+ * a new thread to this file handle entry's thread list.
+ */
+ if ((fha_ctls.max_nfsds_per_fh == 0) ||
+ (fhe->num_threads < fha_ctls.max_nfsds_per_fh)) {
+ /*
+ * We can add a new thread, so try for an idle thread
+ * first, and fall back to this_thread if none are idle.
+ */
+ if (STAILQ_EMPTY(&this_thread->st_reqs)) {
+ thread = this_thread;
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)t", thread, thread->st_reqcount);
+#endif
+ } else if ((thread = get_idle_thread(pool))) {
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)i", thread, thread->st_reqcount);
+#endif
+ } else {
+ thread = this_thread;
+#if 0
+ ITRACE_CURPROC(ITRACE_NFS, ITRACE_INFO,
+ "fha: %p(%d)b", thread, thread->st_reqcount);
+#endif
+ }
+ fha_hash_entry_add_thread(fhe, thread);
+ } else {
+ /*
+ * We don't want to use any more threads for this file, so
+ * go back to the most attractive nfsd we're already using.
+ */
+ thread = min_thread;
+ }
+
+ return (thread);
+}
+
+/*
+ * After getting a request, try to assign it to some thread. Usually we
+ * handle it ourselves.
+ */
+SVCTHREAD *
+fha_assign(SVCTHREAD *this_thread, struct svc_req *req)
+{
+ SVCPOOL *pool;
+ SVCTHREAD *thread;
+ struct fha_info i;
+ struct fha_hash_entry *fhe;
+
+ /*
+ * Only do placement if this is an NFS request.
+ */
+ if (req->rq_prog != NFS_PROG)
+ return (this_thread);
+
+ if (req->rq_vers != 2 && req->rq_vers != 3)
+ return (this_thread);
+
+ pool = req->rq_xprt->xp_pool;
+ fha_extract_info(req, &i);
+
+ /*
+ * We save the offset associated with this request for later
+ * nfsd matching.
+ */
+ fhe = fha_hash_entry_lookup(pool, i.fh);
+ req->rq_p1 = fhe;
+ req->rq_p2 = i.locktype;
+ req->rq_p3 = i.offset;
+
+ /*
+ * Choose a thread, taking into consideration locality, thread load,
+ * and the number of threads already working on this file.
+ */
+ thread = fha_hash_entry_choose_thread(pool, fhe, &i, this_thread);
+ KASSERT(thread, ("fha_assign: NULL thread!"));
+ fha_hash_entry_add_op(fhe, i.locktype, 1);
+
+ return (thread);
+}
+
+/*
+ * Called when we're done with an operation. The request has already
+ * been de-queued.
+ */
+void
+fha_nd_complete(SVCTHREAD *thread, struct svc_req *req)
+{
+ struct fha_hash_entry *fhe = req->rq_p1;
+
+ /*
+ * This may be called for reqs that didn't go through
+ * fha_assign (e.g. extra NULL ops used for RPCSEC_GSS.
+ */
+ if (!fhe)
+ return;
+
+ fha_hash_entry_add_op(fhe, req->rq_p2, -1);
+
+ if (thread->st_reqcount == 0) {
+ fha_hash_entry_remove_thread(fhe, thread);
+ if (0 == fhe->num_reads + fhe->num_writes)
+ fha_hash_entry_remove(fhe);
+ }
+}
+
+extern SVCPOOL *nfsrv_pool;
+
+static int
+fhe_stats_sysctl(SYSCTL_HANDLER_ARGS)
+{
+ int error, count, i;
+ struct sbuf sb;
+ struct fha_hash_entry *fhe;
+ bool_t first = TRUE;
+ SVCTHREAD *thread;
+
+ sbuf_new(&sb, NULL, 4096, SBUF_FIXEDLEN);
+
+ if (!nfsrv_pool) {
+ sbuf_printf(&sb, "NFSD not running\n");
+ goto out;
+ }
+
+ mtx_lock(&nfsrv_pool->sp_lock);
+ count = 0;
+ for (i = 0; i <= g_fha.hashmask; i++)
+ if (!LIST_EMPTY(&g_fha.hashtable[i]))
+ count++;
+
+ if (count == 0) {
+ sbuf_printf(&sb, "No file handle entries.\n");
+ goto out;
+ }
+
+ for (i = 0; i <= g_fha.hashmask; i++) {
+ LIST_FOREACH(fhe, &g_fha.hashtable[i], link) {
+ sbuf_printf(&sb, "%sfhe %p: {\n", first ? "" : ", ", fhe);
+
+ sbuf_printf(&sb, " fh: %ju\n", (uintmax_t) fhe->fh);
+ sbuf_printf(&sb, " num_reads: %d\n", fhe->num_reads);
+ sbuf_printf(&sb, " num_writes: %d\n", fhe->num_writes);
+ sbuf_printf(&sb, " num_threads: %d\n", fhe->num_threads);
+
+ LIST_FOREACH(thread, &fhe->threads, st_alink) {
+ sbuf_printf(&sb, " thread %p (count %d)\n",
+ thread, thread->st_reqcount);
+ }
+
+ sbuf_printf(&sb, "}");
+ first = FALSE;
+
+ /* Limit the output. */
+ if (++count > 128) {
+ sbuf_printf(&sb, "...");
+ break;
+ }
+ }
+ }
+
+ out:
+ if (nfsrv_pool)
+ mtx_unlock(&nfsrv_pool->sp_lock);
+ sbuf_trim(&sb);
+ sbuf_finish(&sb);
+ error = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
+ sbuf_delete(&sb);
+ return (error);
+}
+
+#endif /* !NFS_LEGACYRPC */
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