[PATCHv6 3/3] mm/gup_benchemark: add LONGTERM_BENCHMARK test in gup fast path

From: Pingfan Liu
Date: Mon Mar 16 2020 - 00:37:22 EST


Introduce a PIN_FAST_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: Christoph Hellwig <hch@xxxxxxxxxxxxx>
Cc: Shuah Khan <shuah@xxxxxxxxxx>
Cc: Alexander Duyck <alexander.duyck@xxxxxxxxx>
To: linux-mm@xxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
mm/gup_benchmark.c | 7 +++++++
tools/testing/selftests/vm/gup_benchmark.c | 6 +++++-
2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/mm/gup_benchmark.c b/mm/gup_benchmark.c
index be690fa..09fba20 100644
--- a/mm/gup_benchmark.c
+++ b/mm/gup_benchmark.c
@@ -10,6 +10,7 @@
#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)
+#define PIN_FAST_LONGTERM_BENCHMARK _IOWR('g', 6, struct gup_benchmark)

struct gup_benchmark {
__u64 get_delta_usec;
@@ -101,6 +102,11 @@ static int __gup_benchmark_ioctl(unsigned int cmd,
nr = get_user_pages_fast(addr, nr, gup->flags,
pages + i);
break;
+ case PIN_FAST_LONGTERM_BENCHMARK:
+ nr = get_user_pages_fast(addr, nr,
+ gup->flags | FOLL_LONGTERM,
+ pages + i);
+ break;
case GUP_LONGTERM_BENCHMARK:
nr = get_user_pages(addr, nr,
gup->flags | FOLL_LONGTERM,
@@ -166,6 +172,7 @@ static long gup_benchmark_ioctl(struct file *filep, unsigned int cmd,
case GUP_BENCHMARK:
case PIN_FAST_BENCHMARK:
case PIN_BENCHMARK:
+ case PIN_FAST_LONGTERM_BENCHMARK:
break;
default:
return -EINVAL;
diff --git a/tools/testing/selftests/vm/gup_benchmark.c b/tools/testing/selftests/vm/gup_benchmark.c
index 43b4dfe..f024ff3 100644
--- a/tools/testing/selftests/vm/gup_benchmark.c
+++ b/tools/testing/selftests/vm/gup_benchmark.c
@@ -21,6 +21,7 @@
/* 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)
+#define PIN_FAST_LONGTERM_BENCHMARK _IOWR('g', 6, struct gup_benchmark)

/* Just the flags we need, copied from mm.h: */
#define FOLL_WRITE 0x01 /* check pte is writable */
@@ -44,7 +45,7 @@ int main(int argc, char **argv)
char *file = "/dev/zero";
char *p;

- while ((opt = getopt(argc, argv, "m:r:n:f:abtTLUuwSH")) != -1) {
+ while ((opt = getopt(argc, argv, "m:r:n:f:abtTlLUuwSH")) != -1) {
switch (opt) {
case 'a':
cmd = PIN_FAST_BENCHMARK;
@@ -67,6 +68,9 @@ int main(int argc, char **argv)
case 'T':
thp = 0;
break;
+ case 'l':
+ cmd = PIN_FAST_LONGTERM_BENCHMARK;
+ break;
case 'L':
cmd = GUP_LONGTERM_BENCHMARK;
break;
--
2.7.5