From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D2B34CDB474 for ; Mon, 23 Oct 2023 05:52:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229556AbjJWFwg (ORCPT ); Mon, 23 Oct 2023 01:52:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42944 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229450AbjJWFwf (ORCPT ); Mon, 23 Oct 2023 01:52:35 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 135FEFC for ; Sun, 22 Oct 2023 22:52:34 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33717C433C8; Mon, 23 Oct 2023 05:52:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1698040353; bh=c5e/xj++UlvFH63sLD+CL1Bh5xshEaNjBymMUOkp9mM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=f2DoiuLwo7NGf5IeCzrDxOeExaNpR8NbjkpJs4rf2zwN67g2Q+/R9tMOlJw+MxPS+ ibZ4toyXnVSlp5tq4jrjMTXlFYUbc4NSHEXjX3QeNxn/ZWf4pXeLkJaeIX/HenAVZO hUg9UUVHpRJ/kA0U+a6uZzhC2KuMCXySx6+vNOg0a+PYyO8+AW35yiZOmlr+J5YARO PAvorqVe/KsYTgSjr38U9zAjjy208bJ4eWbDYbPjkVNzY9kPHapQQ9E1CHSwSnJ6fi 5jryWh4KX9jztveEIH3LmQIVR8BB1DRojFLc5Go5CWUgCLfsCoVQ67oz2lG2dfZr0o 0O90RWnH0xDyg== Date: Mon, 23 Oct 2023 08:52:29 +0300 From: Leon Romanovsky To: Guoqing Jiang Cc: Maxim Samoylov , Bernard Metzler , linux-rdma@vger.kernel.org, Jason Gunthorpe , Dennis Dalessandro , Christian Benvenuti , Vadim Fedorenko Subject: Re: [PATCH v2] IB: rework memlock limit handling code Message-ID: <20231023055229.GB10551@unreal> References: <20231012082921.546114-1-max7255@meta.com> <20231015091959.GC25776@unreal> <5fcf502d-71fb-123d-f6ff-f3ffb7c3ba1a@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <5fcf502d-71fb-123d-f6ff-f3ffb7c3ba1a@linux.dev> Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org On Mon, Oct 23, 2023 at 09:40:16AM +0800, Guoqing Jiang wrote: > > > On 10/15/23 17:19, Leon Romanovsky wrote: > > On Thu, Oct 12, 2023 at 01:29:21AM -0700, Maxim Samoylov wrote: > > > This patch provides the uniform handling for RLIM_INFINITY value > > > across the infiniband/rdma subsystem. > > > > > > Currently in some cases the infinity constant is treated > > > as an actual limit value, which could be misleading. > > > > > > Let's also provide the single helper to check against process > > > MEMLOCK limit while registering user memory region mappings. > > > > > > Signed-off-by: Maxim Samoylov > > > --- > > > > > > v1 -> v2: rewritten commit message, rebased on recent upstream > > > > > > drivers/infiniband/core/umem.c | 7 ++----- > > > drivers/infiniband/hw/qib/qib_user_pages.c | 7 +++---- > > > drivers/infiniband/hw/usnic/usnic_uiom.c | 6 ++---- > > > drivers/infiniband/sw/siw/siw_mem.c | 6 +++--- > > > drivers/infiniband/sw/siw/siw_verbs.c | 23 ++++++++++------------ > > > include/rdma/ib_umem.h | 11 +++++++++++ > > > 6 files changed, 31 insertions(+), 29 deletions(-) > > <...> > > > > > @@ -1321,8 +1322,8 @@ struct ib_mr *siw_reg_user_mr(struct ib_pd *pd, u64 start, u64 len, > > > struct siw_umem *umem = NULL; > > > struct siw_ureq_reg_mr ureq; > > > struct siw_device *sdev = to_siw_dev(pd->device); > > > - > > > - unsigned long mem_limit = rlimit(RLIMIT_MEMLOCK); > > > + unsigned long num_pages = > > > + (PAGE_ALIGN(len + (start & ~PAGE_MASK))) >> PAGE_SHIFT; > > > int rv; > > > siw_dbg_pd(pd, "start: 0x%pK, va: 0x%pK, len: %llu\n", > > > @@ -1338,19 +1339,15 @@ struct ib_mr *siw_reg_user_mr(struct ib_pd *pd, u64 start, u64 len, > > > rv = -EINVAL; > > > goto err_out; > > > } > > > - if (mem_limit != RLIM_INFINITY) { > > > - unsigned long num_pages = > > > - (PAGE_ALIGN(len + (start & ~PAGE_MASK))) >> PAGE_SHIFT; > > > - mem_limit >>= PAGE_SHIFT; > > > - if (num_pages > mem_limit - current->mm->locked_vm) { > > > - siw_dbg_pd(pd, "pages req %lu, max %lu, lock %lu\n", > > > - num_pages, mem_limit, > > > - current->mm->locked_vm); > > > - rv = -ENOMEM; > > > - goto err_out; > > > - } > > > + if (!ib_umem_check_rlimit_memlock(num_pages + current->mm->locked_vm)) { > > > + siw_dbg_pd(pd, "pages req %lu, max %lu, lock %lu\n", > > > + num_pages, rlimit(RLIMIT_MEMLOCK), > > > + current->mm->locked_vm); > > > + rv = -ENOMEM; > > > + goto err_out; > > > } > > Sorry for late response, but why does this hunk exist in first place? > > > > > + > > > umem = siw_umem_get(start, len, ib_access_writable(rights)); > > This should be ib_umem_get(). > > IMO, it deserves a separate patch, and replace siw_umem_get with ib_umem_get > is not straightforward given siw_mem has two types of memory (pbl and umem). The thing is that once you convince yourself that SIW should use ib_umem_get(), the same question will arise for other parts of this patch where ib_umem_check_rlimit_memlock() is used. And if we eliminate them all, there won't be a need for this new API call at all. Thanks > > Thanks, > Guoqing