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 <[email protected]>
> Cc: Ira Weiny <[email protected]>
> Cc: Andrew Morton <[email protected]>
> Cc: Mike Rapoport <[email protected]>
> Cc: Dan Williams <[email protected]>
> Cc: Matthew Wilcox <[email protected]>
> Cc: John Hubbard <[email protected]>
> Cc: "Aneesh Kumar K.V" <[email protected]>
> Cc: Keith Busch <[email protected]>
> Cc: Christoph Hellwig <[email protected]>
> Cc: Shuah Khan <[email protected]>
> Cc: [email protected]
> ---
>  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
> 

Reply via email to