From d2269ea14ebd2a73f291d6b3a7a7d320ec00270c Mon Sep 17 00:00:00 2001 From: Trond Myklebust Date: Mon, 27 Jan 2020 09:58:18 -0500 Subject: [PATCH] NFSv4: Add accounting for the number of active delegations held In order to better manage our delegation caching, add a counter to track the number of active delegations. Signed-off-by: Trond Myklebust Signed-off-by: Anna Schumaker --- fs/nfs/delegation.c | 36 ++++++++++++++++++++++++------------ 1 file changed, 24 insertions(+), 12 deletions(-) diff --git a/fs/nfs/delegation.c b/fs/nfs/delegation.c index 90e50f3..a777b3d 100644 --- a/fs/nfs/delegation.c +++ b/fs/nfs/delegation.c @@ -25,13 +25,29 @@ #include "internal.h" #include "nfs4trace.h" -static void nfs_free_delegation(struct nfs_delegation *delegation) +static atomic_long_t nfs_active_delegations; + +static void __nfs_free_delegation(struct nfs_delegation *delegation) { put_cred(delegation->cred); delegation->cred = NULL; kfree_rcu(delegation, rcu); } +static void nfs_mark_delegation_revoked(struct nfs_delegation *delegation) +{ + if (!test_and_set_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) { + delegation->stateid.type = NFS4_INVALID_STATEID_TYPE; + atomic_long_dec(&nfs_active_delegations); + } +} + +static void nfs_free_delegation(struct nfs_delegation *delegation) +{ + nfs_mark_delegation_revoked(delegation); + __nfs_free_delegation(delegation); +} + /** * nfs_mark_delegation_referenced - set delegation's REFERENCED flag * @delegation: delegation to process @@ -343,7 +359,8 @@ nfs_update_inplace_delegation(struct nfs_delegation *delegation, delegation->stateid.seqid = update->stateid.seqid; smp_wmb(); delegation->type = update->type; - clear_bit(NFS_DELEGATION_REVOKED, &delegation->flags); + if (test_and_clear_bit(NFS_DELEGATION_REVOKED, &delegation->flags)) + atomic_long_inc(&nfs_active_delegations); } } @@ -423,6 +440,8 @@ add_new: rcu_assign_pointer(nfsi->delegation, delegation); delegation = NULL; + atomic_long_inc(&nfs_active_delegations); + trace_nfs4_set_delegation(inode, type); spin_lock(&inode->i_lock); @@ -432,7 +451,7 @@ add_new: out: spin_unlock(&clp->cl_lock); if (delegation != NULL) - nfs_free_delegation(delegation); + __nfs_free_delegation(delegation); if (freeme != NULL) { nfs_do_return_delegation(inode, freeme, 0); nfs_free_delegation(freeme); @@ -796,13 +815,6 @@ static void nfs_client_mark_return_unused_delegation_types(struct nfs_client *cl rcu_read_unlock(); } -static void nfs_mark_delegation_revoked(struct nfs_server *server, - struct nfs_delegation *delegation) -{ - set_bit(NFS_DELEGATION_REVOKED, &delegation->flags); - delegation->stateid.type = NFS4_INVALID_STATEID_TYPE; -} - static void nfs_revoke_delegation(struct inode *inode, const nfs4_stateid *stateid) { @@ -830,7 +842,7 @@ static void nfs_revoke_delegation(struct inode *inode, } spin_unlock(&delegation->lock); } - nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation); + nfs_mark_delegation_revoked(delegation); ret = true; out: rcu_read_unlock(); @@ -869,7 +881,7 @@ void nfs_delegation_mark_returned(struct inode *inode, delegation->stateid.seqid = stateid->seqid; } - nfs_mark_delegation_revoked(NFS_SERVER(inode), delegation); + nfs_mark_delegation_revoked(delegation); out_clear_returning: clear_bit(NFS_DELEGATION_RETURNING, &delegation->flags); -- 2.7.4