From: Nathan Chancellor <natechancellor@gmail.com>
To: John Hubbard <jhubbard@nvidia.com>
Cc: "Andrew Morton" <akpm@linux-foundation.org>,
"Al Viro" <viro@zeniv.linux.org.uk>,
"Christoph Hellwig" <hch@infradead.org>,
"Dan Williams" <dan.j.williams@intel.com>,
"Dave Chinner" <david@fromorbit.com>,
"Ira Weiny" <ira.weiny@intel.com>, "Jan Kara" <jack@suse.cz>,
"Jason Gunthorpe" <jgg@ziepe.ca>,
"Jonathan Corbet" <corbet@lwn.net>,
"Jérôme Glisse" <jglisse@redhat.com>,
"Kirill A . Shutemov" <kirill@shutemov.name>,
"Michal Hocko" <mhocko@suse.com>,
"Mike Kravetz" <mike.kravetz@oracle.com>,
"Shuah Khan" <shuah@kernel.org>,
"Vlastimil Babka" <vbabka@suse.cz>,
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 <linux-kernel@vger.kernel.org>,
clang-built-linux@googlegroups.com
Subject: Re: [PATCH 2/3] mm/gup_benchmark: support pin_user_pages() and related calls
Date: Mon, 27 Jan 2020 13:52:47 -0700 [thread overview]
Message-ID: <20200127205247.GA578@Ryzen-7-3700X.localdomain> (raw)
In-Reply-To: <20200125021115.731629-3-jhubbard@nvidia.com>
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 <ira.weiny@intel.com>
> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
> ---
> 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
>
next prev parent reply other threads:[~2020-01-27 20:52 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-25 2:11 [PATCH 0/3] mm/gup: track FOLL_PIN pages (follow on from v12) John Hubbard
2020-01-25 2:11 ` [PATCH 1/3] mm/gup: track FOLL_PIN pages John Hubbard
2020-01-27 11:06 ` Jan Kara
2020-01-27 18:17 ` John Hubbard
2020-01-27 13:00 ` Kirill A. Shutemov
2020-01-27 18:18 ` John Hubbard
2020-01-25 2:11 ` [PATCH 2/3] mm/gup_benchmark: support pin_user_pages() and related calls John Hubbard
2020-01-27 20:52 ` Nathan Chancellor [this message]
2020-01-27 21:32 ` John Hubbard
2020-01-25 2:11 ` [PATCH 3/3] selftests/vm: run_vmtests: invoke gup_benchmark with basic FOLL_PIN coverage John Hubbard
2020-01-25 16:23 ` [PATCH 0/3] mm/gup: track FOLL_PIN pages (follow on from v12) Leon Romanovsky
2020-01-29 5:47 ` Leon Romanovsky
2020-01-29 20:01 ` John Hubbard
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200127205247.GA578@Ryzen-7-3700X.localdomain \
--to=natechancellor@gmail.com \
--cc=akpm@linux-foundation.org \
--cc=clang-built-linux@googlegroups.com \
--cc=corbet@lwn.net \
--cc=dan.j.williams@intel.com \
--cc=david@fromorbit.com \
--cc=hch@infradead.org \
--cc=ira.weiny@intel.com \
--cc=jack@suse.cz \
--cc=jgg@ziepe.ca \
--cc=jglisse@redhat.com \
--cc=jhubbard@nvidia.com \
--cc=kirill@shutemov.name \
--cc=linux-doc@vger.kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-kselftest@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=linux-rdma@vger.kernel.org \
--cc=mhocko@suse.com \
--cc=mike.kravetz@oracle.com \
--cc=shuah@kernel.org \
--cc=vbabka@suse.cz \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).