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 97C36297A42; Mon, 28 Apr 2025 19:37:11 +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=1745869031; cv=none; b=edZht4LnKQdVqKT/cYJkrQ+bWP7620ReJXV61GJBmlqnXmHuCkg5U1UkXScN8uYoCf+EhTlskNTbLpHhSNVa9sZvaVpZ/nVVQc824zylYmThqltcfA4cfWOpZD5yW3fyDKxsFmCnFKpuuv0JGHCFtZeXOJZBAaD13HMGQJGt35E= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745869031; c=relaxed/simple; bh=0OKJoGCLQKnLhkdbONx7kkzAFfQ2qG1W1EiktOh8+es=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=H74JoK/2AakEtDLScKKNlpPBAjTP3IBYFQ+S5pfE0RG5pZPaOJfC1nov8vRjUIfjRmvwB69nS24t8VfLlvTuS8sFeu3ir0XWyxaLMz5BhUp67Jo4BmjxjdoCBW+M2YYjeS6pMQhvgLzoKjeSB0l2TMkx9occRFeNyYblNqI/nkY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=T+Vp23it; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="T+Vp23it" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 43EABC4CEE4; Mon, 28 Apr 2025 19:37:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1745869031; bh=0OKJoGCLQKnLhkdbONx7kkzAFfQ2qG1W1EiktOh8+es=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=T+Vp23itjVzsuc+GUkjs+o8B9t4MEdLrOtNP4WEXt3KV6XMTd+2/Nf1Rsf/63SpBk 4S56eWF8VP+gO3+bwRyGJJ4K5Ea6PJ1sDvYfbJzJ9M7EvF7B5srkW1Ney3qt4dUIsh z8/3NDIRnP74oN/fq/sxfRcSCW9zjUMGExMcSEqaLjgNKDjHWIGwLOY6QsM2hnDKCf qbOjOB4Ajnwz04Wb2BuWnKDCqyBE83IvI3u8cGwJHzAeF6qVrnNy91A0dcbO+mlmvW Mz/JGpYtdzXFSzu1OSE78PUrjQbE1aTYunb8ljU2+E/c8AHlVGj73v3TjvOT7/atLU gSTzgwSFdvIww== From: cel@kernel.org To: NeilBrown , Jeff Layton , Olga Kornievskaia , Dai Ngo , Tom Talpey , Anna Schumaker Cc: , , Chuck Lever Subject: [PATCH v4 05/14] sunrpc: Replace the rq_vec array with dynamically-allocated memory Date: Mon, 28 Apr 2025 15:36:53 -0400 Message-ID: <20250428193702.5186-6-cel@kernel.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250428193702.5186-1-cel@kernel.org> References: <20250428193702.5186-1-cel@kernel.org> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Chuck Lever As a step towards making NFSD's maximum rsize and wsize variable at run-time, replace the fixed-size rq_vec[] array in struct svc_rqst with a chunk of dynamically-allocated memory. The rq_vec array is sized assuming request processing will need at most one kvec per page in a maximum-sized RPC message. On a system with 8-byte pointers and 4KB pages, pahole reports that the rq_vec[] array is 4144 bytes. This patch replaces that array with a single 8-byte pointer field. Reviewed-by: Jeff Layton Signed-off-by: Chuck Lever --- fs/nfsd/vfs.c | 2 +- include/linux/sunrpc/svc.h | 2 +- net/sunrpc/svc.c | 8 +++++++- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 9abdc4b75813..4eaac3aa7e15 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -1094,7 +1094,7 @@ __be32 nfsd_iter_read(struct svc_rqst *rqstp, struct svc_fh *fhp, ++v; base = 0; } - WARN_ON_ONCE(v > ARRAY_SIZE(rqstp->rq_vec)); + WARN_ON_ONCE(v > rqstp->rq_maxpages); trace_nfsd_read_vector(rqstp, fhp, offset, *count); iov_iter_kvec(&iter, ITER_DEST, rqstp->rq_vec, v, *count); diff --git a/include/linux/sunrpc/svc.h b/include/linux/sunrpc/svc.h index ea3a33eec29b..f663d58abd7a 100644 --- a/include/linux/sunrpc/svc.h +++ b/include/linux/sunrpc/svc.h @@ -212,7 +212,7 @@ struct svc_rqst { struct page * *rq_page_end; /* one past the last page */ struct folio_batch rq_fbatch; - struct kvec rq_vec[RPCSVC_MAXPAGES]; /* generally useful.. */ + struct kvec *rq_vec; struct bio_vec rq_bvec[RPCSVC_MAXPAGES]; __be32 rq_xid; /* transmission id */ diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c index 682e11c9be36..5808d4b97547 100644 --- a/net/sunrpc/svc.c +++ b/net/sunrpc/svc.c @@ -675,6 +675,7 @@ static void svc_rqst_free(struct svc_rqst *rqstp) { folio_batch_release(&rqstp->rq_fbatch); + kfree(rqstp->rq_vec); svc_release_buffer(rqstp); if (rqstp->rq_scratch_page) put_page(rqstp->rq_scratch_page); @@ -713,6 +714,11 @@ svc_prepare_thread(struct svc_serv *serv, struct svc_pool *pool, int node) if (!svc_init_buffer(rqstp, serv, node)) goto out_enomem; + rqstp->rq_vec = kcalloc_node(rqstp->rq_maxpages, sizeof(struct kvec), + GFP_KERNEL, node); + if (!rqstp->rq_vec) + goto out_enomem; + rqstp->rq_err = -EAGAIN; /* No error yet */ serv->sv_nrthreads += 1; @@ -1750,7 +1756,7 @@ unsigned int svc_fill_write_vector(struct svc_rqst *rqstp, ++pages; } - WARN_ON_ONCE(i > ARRAY_SIZE(rqstp->rq_vec)); + WARN_ON_ONCE(i > rqstp->rq_maxpages); return i; } EXPORT_SYMBOL_GPL(svc_fill_write_vector); -- 2.49.0