From 3f7e14ad93454476bb11b4b8de5b41930d13312e Mon Sep 17 00:00:00 2001 From: Rick Macklem Date: Sat, 22 May 2021 14:51:38 -0700 Subject: [PATCH] nfscl: Add hash lists for the NFSv4 opens A problem was reported via email, where a large (130000+) accumulation of NFSv4 opens on an NFSv4 mount caused significant lock contention on the mutex used to protect the client mount's open/lock state. Although the root cause for the accumulation of opens was not resolved, it is obvious that the NFSv4 client is not designed to handle 100000+ opens efficiently. When searching for an open, usually for a match by file handle, a linear search of all opens is done. This patch adds a table of hash lists for the opens, hashed on file handle. This table will be used by future commits to search for an open based on file handle more efficiently. MFC after: 2 weeks --- sys/fs/nfs/nfsclstate.h | 7 +++++++ sys/fs/nfsclient/nfs_clstate.c | 15 ++++++++++++++- 2 files changed, 21 insertions(+), 1 deletion(-) diff --git a/sys/fs/nfs/nfsclstate.h b/sys/fs/nfs/nfsclstate.h index e17be74c5581..898a7de391dc 100644 --- a/sys/fs/nfs/nfsclstate.h +++ b/sys/fs/nfs/nfsclstate.h @@ -42,6 +42,7 @@ LIST_HEAD(nfsclhead, nfsclclient); LIST_HEAD(nfsclownerhead, nfsclowner); TAILQ_HEAD(nfscldeleghead, nfscldeleg); LIST_HEAD(nfscldeleghash, nfscldeleg); +LIST_HEAD(nfsclopenhash, nfsclopen); TAILQ_HEAD(nfscllayouthead, nfscllayout); LIST_HEAD(nfscllayouthash, nfscllayout); LIST_HEAD(nfsclflayouthead, nfsclflayout); @@ -50,6 +51,10 @@ LIST_HEAD(nfsclrecalllayouthead, nfsclrecalllayout); #define NFSCLDELEGHASHSIZE 256 #define NFSCLDELEGHASH(c, f, l) \ (&((c)->nfsc_deleghash[ncl_hash((f), (l)) % NFSCLDELEGHASHSIZE])) +#define NFSCLOPENHASHSIZE 256 +#define NFSCLOPENHASHFUNC(f, l) (ncl_hash((f), (l)) % NFSCLOPENHASHSIZE) +#define NFSCLOPENHASH(c, f, l) \ + (&((c)->nfsc_openhash[NFSCLOPENHASHFUNC((f), (l))])) #define NFSCLLAYOUTHASHSIZE 256 #define NFSCLLAYOUTHASH(c, f, l) \ (&((c)->nfsc_layouthash[ncl_hash((f), (l)) % NFSCLLAYOUTHASHSIZE])) @@ -104,6 +109,7 @@ struct nfsclclient { struct nfsclownerhead nfsc_owner; struct nfscldeleghead nfsc_deleg; struct nfscldeleghash nfsc_deleghash[NFSCLDELEGHASHSIZE]; + struct nfsclopenhash nfsc_openhash[NFSCLOPENHASHSIZE]; struct nfscllayouthead nfsc_layout; struct nfscllayouthash nfsc_layouthash[NFSCLLAYOUTHASHSIZE]; struct nfscldevinfohead nfsc_devinfo; @@ -183,6 +189,7 @@ struct nfscldeleg { */ struct nfsclopen { LIST_ENTRY(nfsclopen) nfso_list; + LIST_ENTRY(nfsclopen) nfso_hash; struct nfscllockownerhead nfso_lock; nfsv4stateid_t nfso_stateid; struct nfsclowner *nfso_own; diff --git a/sys/fs/nfsclient/nfs_clstate.c b/sys/fs/nfsclient/nfs_clstate.c index 1ed3630ce6e7..a8eace2ffd0b 100644 --- a/sys/fs/nfsclient/nfs_clstate.c +++ b/sys/fs/nfsclient/nfs_clstate.c @@ -240,9 +240,11 @@ nfscl_open(vnode_t vp, u_int8_t *nfhp, int fhlen, u_int32_t amode, int usedeleg, */ nowp = malloc(sizeof (struct nfsclowner), M_NFSCLOWNER, M_WAITOK); - if (nfhp != NULL) + if (nfhp != NULL) { nop = malloc(sizeof (struct nfsclopen) + fhlen - 1, M_NFSCLOPEN, M_WAITOK); + nop->nfso_hash.le_prev = NULL; + } ret = nfscl_getcl(vp->v_mount, cred, p, 1, &clp); if (ret != 0) { free(nowp, M_NFSCLOWNER); @@ -412,6 +414,8 @@ nfscl_newopen(struct nfsclclient *clp, struct nfscldeleg *dp, dp->nfsdl_timestamp = NFSD_MONOSEC + 120; nfsstatsv1.cllocalopens++; } else { + LIST_INSERT_HEAD(NFSCLOPENHASH(clp, fhp, fhlen), + nop, nfso_hash); nfsstatsv1.clopens++; } LIST_INSERT_HEAD(&owp->nfsow_open, nop, nfso_list); @@ -837,6 +841,8 @@ nfscl_getcl(struct mount *mp, struct ucred *cred, NFSPROC_T *p, LIST_INIT(&clp->nfsc_devinfo); for (i = 0; i < NFSCLDELEGHASHSIZE; i++) LIST_INIT(&clp->nfsc_deleghash[i]); + for (i = 0; i < NFSCLOPENHASHSIZE; i++) + LIST_INIT(&clp->nfsc_openhash[i]); for (i = 0; i < NFSCLLAYOUTHASHSIZE; i++) LIST_INIT(&clp->nfsc_layouthash[i]); clp->nfsc_flags = NFSCLFLAGS_INITED; @@ -1475,6 +1481,8 @@ nfscl_freeopen(struct nfsclopen *op, int local) { LIST_REMOVE(op, nfso_list); + if (op->nfso_hash.le_prev != NULL) + LIST_REMOVE(op, nfso_hash); nfscl_freealllocks(&op->nfso_lock, local); free(op, M_NFSCLOPEN); if (local) @@ -1706,6 +1714,8 @@ nfscl_expireclient(struct nfsclclient *clp, struct nfsmount *nmp, LIST_REMOVE(op, nfso_list); op->nfso_own = towp; LIST_INSERT_HEAD(&towp->nfsow_open, op, nfso_list); + LIST_INSERT_HEAD(NFSCLOPENHASH(clp, op->nfso_fh, + op->nfso_fhlen), op, nfso_hash); nfsstatsv1.cllocalopens--; nfsstatsv1.clopens++; } @@ -1714,6 +1724,8 @@ nfscl_expireclient(struct nfsclclient *clp, struct nfsmount *nmp, LIST_REMOVE(owp, nfsow_list); owp->nfsow_clp = clp; LIST_INSERT_HEAD(&clp->nfsc_owner, owp, nfsow_list); + LIST_INSERT_HEAD(NFSCLOPENHASH(clp, op->nfso_fh, + op->nfso_fhlen), op, nfso_hash); nfsstatsv1.cllocalopenowners--; nfsstatsv1.clopenowners++; nfsstatsv1.cllocalopens--; @@ -4198,6 +4210,7 @@ nfscl_moveopen(vnode_t vp, struct nfsclclient *clp, struct nfsmount *nmp, np = VTONFS(vp); nop = malloc(sizeof (struct nfsclopen) + lop->nfso_fhlen - 1, M_NFSCLOPEN, M_WAITOK); + nop->nfso_hash.le_prev = NULL; newone = 0; nfscl_newopen(clp, NULL, &owp, NULL, &op, &nop, owp->nfsow_owner, lop->nfso_fh, lop->nfso_fhlen, cred, &newone);