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 X-Spam-Level: X-Spam-Status: No, score=-6.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 782FAC2D0DB for ; Mon, 27 Jan 2020 20:52:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 425B124681 for ; Mon, 27 Jan 2020 20:52:58 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="Xrxs/PB3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726296AbgA0Uwy (ORCPT ); Mon, 27 Jan 2020 15:52:54 -0500 Received: from mail-pj1-f65.google.com ([209.85.216.65]:55146 "EHLO mail-pj1-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725955AbgA0Uwy (ORCPT ); Mon, 27 Jan 2020 15:52:54 -0500 Received: by mail-pj1-f65.google.com with SMTP id dw13so6146pjb.4; Mon, 27 Jan 2020 12:52:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=FAvjESqfHP0fRix1omPJhQlHaWmPxKT1qAt5Io3Ecl0=; b=Xrxs/PB39/S+H1IW0+72Sfz/DhvnxYqqn2qJ9YlbcVC9r1TiItpscPOkGQebWqPqNb qN29FKoS9z+zGCshkF3ZhfH1C7sukU5sq/SY3iRNNBnifo84tvPcHJF+PrxosvEW6f7e 0gKup7VweMRIX2jAaOy75EgPOiejG83Mp8X3k2L7FN5CGZssT+Qm/yO++Lb+XBk//8nm Li66s5WTX54iZ2aOJDbzkymJGtVmtJIsjb1G4ciPJWAG0X/g7RtQUWNBCMYTNL+PVLO8 TpSlpocHuuDdA8OK/AHwfRWOv2yUVeTg/gmUv5d0ZbKBgFY4hdjpx4ksZ6FV42vqXMbM tP3g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=FAvjESqfHP0fRix1omPJhQlHaWmPxKT1qAt5Io3Ecl0=; b=lX8z+8g5nL4NrWTfTptCH5HTsgtUYpBjwuqNPlHzEy5rlrLZ4PGkxA9eMY+UNCV/Pc KA5XsR5quwWlOSFFCvqPAJJNWXgzlDCK2KMTjH7VVDykqrKoNb9AU2VmerD41CDNJ8t8 WV43qd25+PT6Oa7CVbvKu2DfbVPWi//vgakUCU8h+s7mZY8/qxH4MDzOHQLSMpGFrGb3 MvMWWTmh4ZTTOJ3st/xDMnh8dogdXy4fElrh/H22Cv3+l4/v+nvoKlwt+avUJTOLj2vu zq9oPjLdnAdmPU2hcE8EylRMjSJhBcuf+hiRZfD4T2t8fDRiCLjomepjqv5+pmk88imk Q/Dg== X-Gm-Message-State: APjAAAWsgeJh29qpfiO2kri4BmJVv84z+rIalsTR5nIs/LeVjQKmYWPi N/xgnJk0ntkGjSa5qF5GXvY= X-Google-Smtp-Source: APXvYqziiwBxEqM+qUPCXXYIJEjli9/gHs667J01IfZYGmcZtgdT4LyE0M0MXDptNU+hyPY434XtzA== X-Received: by 2002:a17:90a:17c2:: with SMTP id q60mr534633pja.111.1580158372874; Mon, 27 Jan 2020 12:52:52 -0800 (PST) Received: from Ryzen-7-3700X.localdomain ([192.200.24.85]) by smtp.gmail.com with ESMTPSA id y197sm17641232pfc.79.2020.01.27.12.52.50 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 27 Jan 2020 12:52:52 -0800 (PST) Date: Mon, 27 Jan 2020 13:52:47 -0700 From: Nathan Chancellor To: John Hubbard Cc: Andrew Morton , Al Viro , Christoph Hellwig , Dan Williams , Dave Chinner , Ira Weiny , Jan Kara , Jason Gunthorpe , Jonathan Corbet , =?iso-8859-1?B?Suly9G1l?= Glisse , "Kirill A . Shutemov" , Michal Hocko , Mike Kravetz , Shuah Khan , Vlastimil Babka , linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-rdma@vger.kernel.org, linux-mm@kvack.org, LKML , clang-built-linux@googlegroups.com Subject: Re: [PATCH 2/3] mm/gup_benchmark: support pin_user_pages() and related calls Message-ID: <20200127205247.GA578@Ryzen-7-3700X.localdomain> References: <20200125021115.731629-1-jhubbard@nvidia.com> <20200125021115.731629-3-jhubbard@nvidia.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200125021115.731629-3-jhubbard@nvidia.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Hi John, On Fri, Jan 24, 2020 at 06:11:14PM -0800, John Hubbard wrote: > Up until now, gup_benchmark supported testing of the > following kernel functions: > > * get_user_pages(): via the '-U' command line option > * get_user_pages_longterm(): via the '-L' command line option > * get_user_pages_fast(): as the default (no options required) > > Add test coverage for the new corresponding pin_*() functions: > > * pin_user_pages_fast(): via the '-a' command line option > * pin_user_pages(): via the '-b' command line option > > Also, add an option for clarity: '-u' for what is now (still) the > default choice: get_user_pages_fast(). > > Also, for the commands that set FOLL_PIN, verify that the pages > really are dma-pinned, via the new is_dma_pinned() routine. > Those commands are: > > PIN_FAST_BENCHMARK : calls pin_user_pages_fast() > PIN_BENCHMARK : calls pin_user_pages() > > In between the calls to pin_*() and unpin_user_pages(), > check each page: if page_dma_pinned() returns false, then > WARN and return. > > Do this outside of the benchmark timestamps, so that it doesn't > affect reported times. > > Reviewed-by: Ira Weiny > Signed-off-by: John Hubbard > --- > mm/gup_benchmark.c | 70 ++++++++++++++++++++-- > tools/testing/selftests/vm/gup_benchmark.c | 15 ++++- > 2 files changed, 79 insertions(+), 6 deletions(-) > > diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c > index 8dba38e79a9f..3d5fb765e4e6 100644 > --- a/mm/gup_benchmark.c > +++ b/mm/gup_benchmark.c > @@ -8,6 +8,8 @@ > #define GUP_FAST_BENCHMARK _IOWR('g', 1, struct gup_benchmark) > #define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) > #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) > +#define PIN_FAST_BENCHMARK _IOWR('g', 4, struct gup_benchmark) > +#define PIN_BENCHMARK _IOWR('g', 5, struct gup_benchmark) > > struct gup_benchmark { > __u64 get_delta_usec; > @@ -19,6 +21,47 @@ struct gup_benchmark { > __u64 expansion[10]; /* For future use */ > }; > > +static void put_back_pages(int cmd, struct page **pages, unsigned long nr_pages) We received a Clang build report on this patch because the use of PIN_FAST_BENCHMARK and PIN_BENCHMARK in the switch statement below will overflow int; this should be unsigned int to match the cmd parameter in the ioctls. The report can be read here if you care for it: https://groups.google.com/d/msg/clang-built-linux/gyGayC_dnis/D1celSStEgAJ Cheers, Nathan > +{ > + int i; > + > + switch (cmd) { > + case GUP_FAST_BENCHMARK: > + case GUP_LONGTERM_BENCHMARK: > + case GUP_BENCHMARK: > + for (i = 0; i < nr_pages; i++) > + put_page(pages[i]); > + break; > + > + case PIN_FAST_BENCHMARK: > + case PIN_BENCHMARK: > + unpin_user_pages(pages, nr_pages); > + break; > + } > +} > + > +static void verify_dma_pinned(int cmd, struct page **pages, > + unsigned long nr_pages) > +{ > + int i; > + struct page *page; > + > + switch (cmd) { > + case PIN_FAST_BENCHMARK: > + case PIN_BENCHMARK: > + for (i = 0; i < nr_pages; i++) { > + page = pages[i]; > + if (WARN(!page_dma_pinned(page), > + "pages[%d] is NOT dma-pinned\n", i)) { > + > + dump_page(page, "gup_benchmark failure"); > + break; > + } > + } > + break; > + } > +} > + > static int __gup_benchmark_ioctl(unsigned int cmd, > struct gup_benchmark *gup) > { > @@ -66,6 +109,14 @@ static int __gup_benchmark_ioctl(unsigned int cmd, > nr = get_user_pages(addr, nr, gup->flags, pages + i, > NULL); > break; > + case PIN_FAST_BENCHMARK: > + nr = pin_user_pages_fast(addr, nr, gup->flags, > + pages + i); > + break; > + case PIN_BENCHMARK: > + nr = pin_user_pages(addr, nr, gup->flags, pages + i, > + NULL); > + break; > default: > kvfree(pages); > ret = -EINVAL; > @@ -78,15 +129,22 @@ static int __gup_benchmark_ioctl(unsigned int cmd, > } > end_time = ktime_get(); > > + /* Shifting the meaning of nr_pages: now it is actual number pinned: */ > + nr_pages = i; > + > gup->get_delta_usec = ktime_us_delta(end_time, start_time); > gup->size = addr - gup->addr; > > + /* > + * Take an un-benchmark-timed moment to verify DMA pinned > + * state: print a warning if any non-dma-pinned pages are found: > + */ > + verify_dma_pinned(cmd, pages, nr_pages); > + > start_time = ktime_get(); > - for (i = 0; i < nr_pages; i++) { > - if (!pages[i]) > - break; > - put_page(pages[i]); > - } > + > + put_back_pages(cmd, pages, nr_pages); > + > end_time = ktime_get(); > gup->put_delta_usec = ktime_us_delta(end_time, start_time); > > @@ -105,6 +163,8 @@ static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd, > case GUP_FAST_BENCHMARK: > case GUP_LONGTERM_BENCHMARK: > case GUP_BENCHMARK: > + case PIN_FAST_BENCHMARK: > + case PIN_BENCHMARK: > break; > default: > return -EINVAL; > diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c > index 389327e9b30a..43b4dfe161a2 100644 > --- a/tools/testing/selftests/vm/gup_benchmark.c > +++ b/tools/testing/selftests/vm/gup_benchmark.c > @@ -18,6 +18,10 @@ > #define GUP_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark) > #define GUP_BENCHMARK _IOWR('g', 3, struct gup_benchmark) > > +/* Similar to above, but use FOLL_PIN instead of FOLL_GET. */ > +#define PIN_FAST_BENCHMARK _IOWR('g', 4, struct gup_benchmark) > +#define PIN_BENCHMARK _IOWR('g', 5, struct gup_benchmark) > + > /* Just the flags we need, copied from mm.h: */ > #define FOLL_WRITE 0x01 /* check pte is writable */ > > @@ -40,8 +44,14 @@ int main(int argc, char **argv) > char *file = "/dev/zero"; > char *p; > > - while ((opt = getopt(argc, argv, "m:r:n:f:tTLUwSH")) != -1) { > + while ((opt = getopt(argc, argv, "m:r:n:f:abtTLUuwSH")) != -1) { > switch (opt) { > + case 'a': > + cmd = PIN_FAST_BENCHMARK; > + break; > + case 'b': > + cmd = PIN_BENCHMARK; > + break; > case 'm': > size = atoi(optarg) * MB; > break; > @@ -63,6 +73,9 @@ int main(int argc, char **argv) > case 'U': > cmd = GUP_BENCHMARK; > break; > + case 'u': > + cmd = GUP_FAST_BENCHMARK; > + break; > case 'w': > write = 1; > break; > -- > 2.25.0 >