From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-177.mta0.migadu.com (out-177.mta0.migadu.com [91.218.175.177]) (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 D1DAB3D544 for ; Sun, 8 Jun 2025 11:23:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.177 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749381810; cv=none; b=N5HKgBE0N04KG8rP0SCbNYYuiMHvSWo/GFWoyQzMF5Px5ktYbDsmPERKlNBA0jDDnCFCcuBEbIgM286tKM8Evi4Zvb3CnxCGtAah67W0o26gUD6k1+w4zzFnPT/m3mueSUih7mi3os+9qR10WPDJmTrlLY1Osq6kXV1R7Mj0bvg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749381810; c=relaxed/simple; bh=vBmVa7+HT3ViIIYGboa8Z7ZUcGoENSu0gRQmBGL1pBU=; h=Message-ID:Date:MIME-Version:Subject:To:References:From: In-Reply-To:Content-Type; b=Rk2JHmIDpc9EVSeHdr2p1P5bngl1WFJdtOZmY6TU1ubR/eTpWmrw/KcGWfbsV51TpAMaiXvkKAMUNKXwlDNi12mA0sC3ObpA6U/F0Ijlv2vJpzIOJl3fK1TYsSdE8XCkBvaGXF76IFNNCIwiH2PSrdGl2te00dHeFTc5HA2HZpY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=e2mA5F9H; arc=none smtp.client-ip=91.218.175.177 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="e2mA5F9H" Message-ID: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1749381805; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=oV/g9IcWkYk25U7TyFCt/av8AbniaH2IFDp1/9aw+TQ=; b=e2mA5F9HSorfB/NsPDyc/ilcbaVo0SUniYatRyTNlS2nSvgGIgiqg9U9BRHSkjACrnXxSY waQiCR8FiFytxDrAob8ggh4MbtZvScsF9GT9WUJ7wBi4b8hQgZX8+q6LEyYsjhoLm+kGlj cY4WN4pITv2DOiS1hl/8d1wTx3KPlI8= Date: Sun, 8 Jun 2025 13:23:19 +0200 Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH for-next v2] RDMA/rxe: Remove redundant page presence check To: Daisuke Matsuda , linux-rdma@vger.kernel.org, leon@kernel.org, jgg@ziepe.ca, zyjzyj2000@gmail.com References: <20250608095916.6313-1-dskmtsd@gmail.com> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Zhu Yanjun In-Reply-To: <20250608095916.6313-1-dskmtsd@gmail.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT 在 2025/6/8 11:59, Daisuke Matsuda 写道: > hmm_pfn_to_page() does not return NULL. ib_umem_odp_map_dma_and_lock() > should return an error in case the target pages cannot be mapped until > timeout, so these checks can safely be removed. > > Signed-off-by: Daisuke Matsuda > --- > drivers/infiniband/sw/rxe/rxe_odp.c | 13 +------------ > 1 file changed, 1 insertion(+), 12 deletions(-) > > diff --git a/drivers/infiniband/sw/rxe/rxe_odp.c b/drivers/infiniband/sw/rxe/rxe_odp.c > index dbc5a5600eb7..02841346e30c 100644 > --- a/drivers/infiniband/sw/rxe/rxe_odp.c > +++ b/drivers/infiniband/sw/rxe/rxe_odp.c > @@ -203,8 +203,6 @@ static int __rxe_odp_mr_copy(struct rxe_mr *mr, u64 iova, void *addr, > > page = hmm_pfn_to_page(umem_odp->map.pfn_list[idx]); > user_va = kmap_local_page(page); > - if (!user_va) > - return -EFAULT; > > src = (dir == RXE_TO_MR_OBJ) ? addr : user_va; > dest = (dir == RXE_TO_MR_OBJ) ? user_va : addr; > @@ -286,8 +284,6 @@ static enum resp_states rxe_odp_do_atomic_op(struct rxe_mr *mr, u64 iova, > idx = rxe_odp_iova_to_index(umem_odp, iova); > page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova); > page = hmm_pfn_to_page(umem_odp->map.pfn_list[idx]); The function hmm_pfn_to_page will finally be "(mem_map + ((pfn) - ARCH_PFN_OFFSET))" The procedure is as below: hmm_pfn_to_page -- > pfn_to_page -- > __pfn_to_page -- > (mem_map + ((pfn) - ARCH_PFN_OFFSET)) Thus, I am fine with it. > - if (!page) > - return RESPST_ERR_RKEY_VIOLATION; > > if (unlikely(page_offset & 0x7)) { Normally page_offset error handler should be after this line "page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova);" Why is this error handler after hmm_pfn_to_page? > rxe_dbg_mr(mr, "iova not aligned\n"); > @@ -352,10 +348,6 @@ int rxe_odp_flush_pmem_iova(struct rxe_mr *mr, u64 iova, > page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova); > > page = hmm_pfn_to_page(umem_odp->map.pfn_list[index]); > - if (!page) { > - mutex_unlock(&umem_odp->umem_mutex); > - return -EFAULT; > - } > > bytes = min_t(unsigned int, length, > mr_page_size(mr) - page_offset); > @@ -398,10 +390,7 @@ enum resp_states rxe_odp_do_atomic_write(struct rxe_mr *mr, u64 iova, u64 value) > page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova); > index = rxe_odp_iova_to_index(umem_odp, iova); > page = hmm_pfn_to_page(umem_odp->map.pfn_list[index]); > - if (!page) { > - mutex_unlock(&umem_odp->umem_mutex); > - return RESPST_ERR_RKEY_VIOLATION; > - } > + > /* See IBA A19.4.2 */ > if (unlikely(page_offset & 0x7)) { Ditto, page_offset error handler is not after the line "page_offset = rxe_odp_iova_to_page_offset(umem_odp, iova);" ? Thanks Yanjun.Zhu > mutex_unlock(&umem_odp->umem_mutex);