From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 5E2B56EB72; Mon, 8 Apr 2024 13:53:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712584410; cv=none; b=dKHj8Nm/YiTx1bm7DyF79qrD5/z7mnWs3x5sWtiM0Mn6OLqtRwl8Bh5E76QU7yJuU7PURLKXAp2CTlW+fM0tZ+DhbAtu/FvfYv6pcruS+aX0F0L+HNEks9DFZIYr5dimZieiKevUBAOXw2wefLIbWzERyyUazGe9Y2Ot+aK5yAE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712584410; c=relaxed/simple; bh=taLhaOU4tF+R17HE4kzeYFMLLuRayI7MYwPfS0faN1c=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=A7UM8bYpttkeDOWlpfdkSEWhTXbQxjHmoiDjArspf0Bt1AvsP1tkQYciNM1urskjufc508vTKiM4ASYxCp6W6GppdUrlbJfxtM0J0CjhS45qU4hvMoLpAtIQbCTxvY5GAxjV1G7wkYNMTnjA0N+baHJgdeBj8eqtNB5EcMV879c= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=O/Z/afKl; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="O/Z/afKl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id DAC60C433C7; Mon, 8 Apr 2024 13:53:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712584410; bh=taLhaOU4tF+R17HE4kzeYFMLLuRayI7MYwPfS0faN1c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=O/Z/afKlO4rgoy9Mwv5bUlk0IsMBXbvv3Y6BrkfPomjtHgGoTMnfpKxQiY/CC22rx 8j3RkrhmVSv4Hkyl9QHn3cwsDdvkC9EUuYpcu2rBv3zoscvW7K+caXeQNEY/dZvFcu 8U72rRUy8nM7wcBVryrpqRsdkmbP2Ri5usZoFRCo= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jeff Layton , Chuck Lever Subject: [PATCH 5.15 429/690] NFSD: Add a mechanism to wait for a DELEGRETURN Date: Mon, 8 Apr 2024 14:54:55 +0200 Message-ID: <20240408125415.135625578@linuxfoundation.org> X-Mailer: git-send-email 2.44.0 In-Reply-To: <20240408125359.506372836@linuxfoundation.org> References: <20240408125359.506372836@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chuck Lever [ Upstream commit c035362eb935fe9381d9d1cc453bc2a37460e24c ] Subsequent patches will use this mechanism to wake up an operation that is waiting for a client to return a delegation. The new tracepoint records whether the wait timed out or was properly awoken by the expected DELEGRETURN: nfsd-1155 [002] 83799.493199: nfsd_delegret_wakeup: xid=0x14b7d6ef fh_hash=0xf6826792 (timed out) Suggested-by: Jeff Layton Signed-off-by: Chuck Lever Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever --- fs/nfsd/nfs4state.c | 30 ++++++++++++++++++++++++++++++ fs/nfsd/nfsd.h | 7 +++++++ fs/nfsd/trace.h | 23 +++++++++++++++++++++++ 3 files changed, 60 insertions(+) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index a0c5658599ead..6cb654e308787 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4734,6 +4734,35 @@ nfs4_share_conflict(struct svc_fh *current_fh, unsigned int deny_type) return ret; } +static bool nfsd4_deleg_present(const struct inode *inode) +{ + struct file_lock_context *ctx = smp_load_acquire(&inode->i_flctx); + + return ctx && !list_empty_careful(&ctx->flc_lease); +} + +/** + * nfsd_wait_for_delegreturn - wait for delegations to be returned + * @rqstp: the RPC transaction being executed + * @inode: in-core inode of the file being waited for + * + * The timeout prevents deadlock if all nfsd threads happen to be + * tied up waiting for returning delegations. + * + * Return values: + * %true: delegation was returned + * %false: timed out waiting for delegreturn + */ +bool nfsd_wait_for_delegreturn(struct svc_rqst *rqstp, struct inode *inode) +{ + long __maybe_unused timeo; + + timeo = wait_var_event_timeout(inode, !nfsd4_deleg_present(inode), + NFSD_DELEGRETURN_TIMEOUT); + trace_nfsd_delegret_wakeup(rqstp, inode, timeo); + return timeo > 0; +} + static void nfsd4_cb_recall_prepare(struct nfsd4_callback *cb) { struct nfs4_delegation *dp = cb_to_delegation(cb); @@ -6797,6 +6826,7 @@ nfsd4_delegreturn(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate, if (status) goto put_stateid; + wake_up_var(d_inode(cstate->current_fh.fh_dentry)); destroy_delegation(dp); put_stateid: nfs4_put_stid(&dp->dl_stid); diff --git a/fs/nfsd/nfsd.h b/fs/nfsd/nfsd.h index 57a468ed85c35..6ab4ad41ae84e 100644 --- a/fs/nfsd/nfsd.h +++ b/fs/nfsd/nfsd.h @@ -164,6 +164,7 @@ char * nfs4_recoverydir(void); bool nfsd4_spo_must_allow(struct svc_rqst *rqstp); int nfsd4_create_laundry_wq(void); void nfsd4_destroy_laundry_wq(void); +bool nfsd_wait_for_delegreturn(struct svc_rqst *rqstp, struct inode *inode); #else static inline int nfsd4_init_slabs(void) { return 0; } static inline void nfsd4_free_slabs(void) { } @@ -179,6 +180,11 @@ static inline bool nfsd4_spo_must_allow(struct svc_rqst *rqstp) } static inline int nfsd4_create_laundry_wq(void) { return 0; }; static inline void nfsd4_destroy_laundry_wq(void) {}; +static inline bool nfsd_wait_for_delegreturn(struct svc_rqst *rqstp, + struct inode *inode) +{ + return false; +} #endif /* @@ -343,6 +349,7 @@ void nfsd_lockd_shutdown(void); #define NFSD_COURTESY_CLIENT_TIMEOUT (24 * 60 * 60) /* seconds */ #define NFSD_CLIENT_MAX_TRIM_PER_RUN 128 #define NFS4_CLIENTS_PER_GB 1024 +#define NFSD_DELEGRETURN_TIMEOUT (HZ / 34) /* 30ms */ /* * The following attributes are currently not supported by the NFSv4 server: diff --git a/fs/nfsd/trace.h b/fs/nfsd/trace.h index d832429e575e4..1229502b6e9e0 100644 --- a/fs/nfsd/trace.h +++ b/fs/nfsd/trace.h @@ -538,6 +538,29 @@ DEFINE_NFSD_COPY_ERR_EVENT(clone_file_range_err); #include "filecache.h" #include "vfs.h" +TRACE_EVENT(nfsd_delegret_wakeup, + TP_PROTO( + const struct svc_rqst *rqstp, + const struct inode *inode, + long timeo + ), + TP_ARGS(rqstp, inode, timeo), + TP_STRUCT__entry( + __field(u32, xid) + __field(const void *, inode) + __field(long, timeo) + ), + TP_fast_assign( + __entry->xid = be32_to_cpu(rqstp->rq_xid); + __entry->inode = inode; + __entry->timeo = timeo; + ), + TP_printk("xid=0x%08x inode=%p%s", + __entry->xid, __entry->inode, + __entry->timeo == 0 ? " (timed out)" : "" + ) +); + DECLARE_EVENT_CLASS(nfsd_stateid_class, TP_PROTO(stateid_t *stp), TP_ARGS(stp), -- 2.43.0