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 C50067E58C; Mon, 8 Apr 2024 13:57:50 +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=1712584670; cv=none; b=VRtCp1MYebbtBW3eLF1FLDI1HrlMZGxOXlimcuMRhZW57IA0PqW4na+bQqXaxj5xwd89IMT2gAJXuh6skd28t24IfxXZPJIpDo/SiBy+9L0U/Oh1x0w3Xxf/n2sgdJPPihloGdLrAKqHVlDk2SZHuIeojSGWRFqlCQBdJlMf2Eg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1712584670; c=relaxed/simple; bh=Kfos+pI/Ix/J+pClD9gVm/bNXxdW837qb9N7xi6iwdc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WxwXGLn/0+EGKohBc/6ucNf8RjRlETIm7B5HA6GyYoD1ScS6Ks1gREekX/1ZDfNdaa6dUeu0q/Kd+FYpmybvJGdXJHYrTPJ6YgQELo9UC/W9T5lVjSO2/Yw4V1ADmnk/O4F2a25cTGJJBTehBFu9fFNhYQF4DmnzjBmKNLXzqTM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=u5f+lEyc; 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="u5f+lEyc" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5029CC433F1; Mon, 8 Apr 2024 13:57:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1712584670; bh=Kfos+pI/Ix/J+pClD9gVm/bNXxdW837qb9N7xi6iwdc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=u5f+lEycn9Sz+KygCYZB3qSB84rbTot66iK1Z824m+1V7W2kjuPXPcuyT/fjrxB6f Npr/SPjlOPg2dlFo5u5N+OE2S2JJitUnhsv7X0VepSalXFn0tmDiuMDPVcXxoCjuM0 zUnClCBo8T8lEpGVbgYzK0tIahNTXXln6k6ta2fk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Chuck Lever , NeilBrown Subject: [PATCH 5.15 488/690] NFSD: Clean up find_or_add_file() Date: Mon, 8 Apr 2024 14:55:54 +0200 Message-ID: <20240408125417.324307489@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 9270fc514ba7d415636b23bcb937573a1ce54f6a ] Remove the call to find_file_locked() in insert_nfs4_file(). Tracing shows that over 99% of these calls return NULL. Thus it is not worth the expense of the extra bucket list traversal. insert_file() already deals correctly with the case where the item is already in the hash bucket. Since nfsd4_file_hash_insert() is now just a wrapper around insert_file(), move the meat of insert_file() into nfsd4_file_hash_insert() and get rid of it. Signed-off-by: Chuck Lever Reviewed-by: NeilBrown Signed-off-by: Chuck Lever --- fs/nfsd/nfs4state.c | 64 ++++++++++++++++++++------------------------- 1 file changed, 28 insertions(+), 36 deletions(-) diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c index f723d7d5e1557..192e721525665 100644 --- a/fs/nfsd/nfs4state.c +++ b/fs/nfsd/nfs4state.c @@ -4698,24 +4698,42 @@ find_file_locked(const struct svc_fh *fh, unsigned int hashval) return NULL; } -static struct nfs4_file *insert_file(struct nfs4_file *new, struct svc_fh *fh, - unsigned int hashval) +static struct nfs4_file * find_file(struct svc_fh *fh) { struct nfs4_file *fp; + unsigned int hashval = file_hashval(fh); + + rcu_read_lock(); + fp = find_file_locked(fh, hashval); + rcu_read_unlock(); + return fp; +} + +/* + * On hash insertion, identify entries with the same inode but + * distinct filehandles. They will all be in the same hash bucket + * because nfs4_file's are hashed by the address in the fi_inode + * field. + */ +static noinline_for_stack struct nfs4_file * +nfsd4_file_hash_insert(struct nfs4_file *new, const struct svc_fh *fhp) +{ + unsigned int hashval = file_hashval(fhp); struct nfs4_file *ret = NULL; bool alias_found = false; + struct nfs4_file *fi; spin_lock(&state_lock); - hlist_for_each_entry_rcu(fp, &file_hashtbl[hashval], fi_hash, + hlist_for_each_entry_rcu(fi, &file_hashtbl[hashval], fi_hash, lockdep_is_held(&state_lock)) { - if (fh_match(&fp->fi_fhandle, &fh->fh_handle)) { - if (refcount_inc_not_zero(&fp->fi_ref)) - ret = fp; - } else if (d_inode(fh->fh_dentry) == fp->fi_inode) - fp->fi_aliased = alias_found = true; + if (fh_match(&fi->fi_fhandle, &fhp->fh_handle)) { + if (refcount_inc_not_zero(&fi->fi_ref)) + ret = fi; + } else if (d_inode(fhp->fh_dentry) == fi->fi_inode) + fi->fi_aliased = alias_found = true; } if (likely(ret == NULL)) { - nfsd4_file_init(fh, new); + nfsd4_file_init(fhp, new); hlist_add_head_rcu(&new->fi_hash, &file_hashtbl[hashval]); new->fi_aliased = alias_found; ret = new; @@ -4724,32 +4742,6 @@ static struct nfs4_file *insert_file(struct nfs4_file *new, struct svc_fh *fh, return ret; } -static struct nfs4_file * find_file(struct svc_fh *fh) -{ - struct nfs4_file *fp; - unsigned int hashval = file_hashval(fh); - - rcu_read_lock(); - fp = find_file_locked(fh, hashval); - rcu_read_unlock(); - return fp; -} - -static struct nfs4_file * -find_or_add_file(struct nfs4_file *new, struct svc_fh *fh) -{ - struct nfs4_file *fp; - unsigned int hashval = file_hashval(fh); - - rcu_read_lock(); - fp = find_file_locked(fh, hashval); - rcu_read_unlock(); - if (fp) - return fp; - - return insert_file(new, fh, hashval); -} - static noinline_for_stack void nfsd4_file_hash_remove(struct nfs4_file *fi) { hlist_del_rcu(&fi->fi_hash); @@ -5641,7 +5633,7 @@ nfsd4_process_open2(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nf * and check for delegations in the process of being recalled. * If not found, create the nfs4_file struct */ - fp = find_or_add_file(open->op_file, current_fh); + fp = nfsd4_file_hash_insert(open->op_file, current_fh); if (fp != open->op_file) { status = nfs4_check_deleg(cl, open, &dp); if (status) -- 2.43.0