On Thu, Jun 13, 2019 at 06:45:02PM +0800, Pingfan Liu wrote:
> Introduce a GUP_LONGTERM_BENCHMARK ioctl to test longterm pin in gup fast
> path.
>
> Signed-off-by: Pingfan Liu <kernelfans@xxxxxxxxx>
> Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx>
> Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> Cc: John Hubbard <jhubbard@xxxxxxxxxx>
> Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx>
> Cc: Keith Busch <keith.busch@xxxxxxxxx>
> Cc: Christoph Hellwig <hch@xxxxxxxxxxxxx>
> Cc: Shuah Khan <shuah@xxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> ---
> mm/gup_benchmark.c | 11 +++++++++--
> tools/testing/selftests/vm/gup_benchmark.c | 10 +++++++---
> 2 files changed, 16 insertions(+), 5 deletions(-)
>
> diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c
> index 7dd602d..83f3378 100644
> --- a/mm/gup_benchmark.c
> +++ b/mm/gup_benchmark.c
> @@ -6,8 +6,9 @@
> #include <linux/debugfs.h>
>
> #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 GUP_FAST_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark)
> +#define GUP_LONGTERM_BENCHMARK _IOWR('g', 3, struct gup_benchmark)
> +#define GUP_BENCHMARK _IOWR('g', 4, struct gup_benchmark)
But I really like this addition! Thanks!
But why not just add GUP_FAST_LONGTERM_BENCHMARK to the end of this list (value
4)? I know the user space test program is probably expected to be lock step
with this code but it seems odd to redefine GUP_LONGTERM_BENCHMARK and
GUP_BENCHMARK with this change.
Ira
>
> struct gup_benchmark {
> __u64 get_delta_usec;
> @@ -53,6 +54,11 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
> nr = get_user_pages_fast(addr, nr, gup->flags & 1,
> pages + i);
> break;
> + case GUP_FAST_LONGTERM_BENCHMARK:
> + nr = get_user_pages_fast(addr, nr,
> + (gup->flags & 1) | FOLL_LONGTERM,
> + pages + i);
> + break;
> case GUP_LONGTERM_BENCHMARK:
> nr = get_user_pages(addr, nr,
> (gup->flags & 1) | FOLL_LONGTERM,
> @@ -96,6 +102,7 @@ static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd,
>
> switch (cmd) {
> case GUP_FAST_BENCHMARK:
> + case GUP_FAST_LONGTERM_BENCHMARK:
> case GUP_LONGTERM_BENCHMARK:
> case GUP_BENCHMARK:
> break;
> diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c
> index c0534e2..ade8acb 100644
> --- a/tools/testing/selftests/vm/gup_benchmark.c
> +++ b/tools/testing/selftests/vm/gup_benchmark.c
> @@ -15,8 +15,9 @@
> #define PAGE_SIZE sysconf(_SC_PAGESIZE)
>
> #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 GUP_FAST_LONGTERM_BENCHMARK _IOWR('g', 2, struct gup_benchmark)
> +#define GUP_LONGTERM_BENCHMARK _IOWR('g', 3, struct gup_benchmark)
> +#define GUP_BENCHMARK _IOWR('g', 4, struct gup_benchmark)
>
> struct gup_benchmark {
> __u64 get_delta_usec;
> @@ -37,7 +38,7 @@ int main(int argc, char **argv)
> char *file = "/dev/zero";
> char *p;
>
> - while ((opt = getopt(argc, argv, "m:r:n:f:tTLUSH")) != -1) {
> + while ((opt = getopt(argc, argv, "m:r:n:f:tTlLUSH")) != -1) {
> switch (opt) {
> case 'm':
> size = atoi(optarg) * MB;
> @@ -54,6 +55,9 @@ int main(int argc, char **argv)
> case 'T':
> thp = 0;
> break;
> + case 'l':
> + cmd = GUP_FAST_LONGTERM_BENCHMARK;
> + break;
> case 'L':
> cmd = GUP_LONGTERM_BENCHMARK;
> break;
> --
> 2.7.5
>
