Am 2022-02-01 um 02:05 schrieb Alistair Popple:
> From: Alex Sierra <[email protected]>
>
> The intention is to test device coherent type pages that have been
> called through get user pages with PIN_LONGTERM flag set. These pages
> should get migrated back to normal system memory.
>
> Signed-off-by: Alex Sierra <[email protected]>
> Signed-off-by: Alistair Popple <[email protected]>
This patch is
Reviewed-by: Felix Kuehling <[email protected]>
> ---
> tools/testing/selftests/vm/Makefile | 2 +-
> tools/testing/selftests/vm/hmm-tests.c | 81 +++++++++++++++++++++++++++-
> 2 files changed, 82 insertions(+), 1 deletion(-)
>
> diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile
> index 1607322..58c8427 100644
> --- a/tools/testing/selftests/vm/Makefile
> +++ b/tools/testing/selftests/vm/Makefile
> @@ -142,7 +142,7 @@ $(OUTPUT)/mlock-random-test $(OUTPUT)/memfd_secret: LDLIBS += -lcap
>
> $(OUTPUT)/gup_test: ../../../../mm/gup_test.h
>
> -$(OUTPUT)/hmm-tests: local_config.h
> +$(OUTPUT)/hmm-tests: local_config.h ../../../../mm/gup_test.h
>
> # HMM_EXTRA_LIBS may get set in local_config.mk, or it may be left empty.
> $(OUTPUT)/hmm-tests: LDLIBS += $(HMM_EXTRA_LIBS)
> diff --git a/tools/testing/selftests/vm/hmm-tests.c b/tools/testing/selftests/vm/hmm-tests.c
> index 84ec8c4..11b83a8 100644
> --- a/tools/testing/selftests/vm/hmm-tests.c
> +++ b/tools/testing/selftests/vm/hmm-tests.c
> @@ -36,6 +36,7 @@
> * in the usual include/uapi/... directory.
> */
> #include "../../../../lib/test_hmm_uapi.h"
> +#include "../../../../mm/gup_test.h"
>
> struct hmm_buffer {
> void *ptr;
> @@ -60,6 +61,8 @@ enum {
> #define NTIMES 10
>
> #define ALIGN(x, a) (((x) + (a - 1)) & (~((a) - 1)))
> +/* Just the flags we need, copied from mm.h: */
> +#define FOLL_WRITE 0x01 /* check pte is writable */
>
> FIXTURE(hmm)
> {
> @@ -1766,4 +1769,82 @@ TEST_F(hmm, exclusive_cow)
> hmm_buffer_free(buffer);
> }
>
> +/*
> + * Test get user device pages through gup_test. Setting PIN_LONGTERM flag.
> + * This should trigger a migration back to system memory for both, private
> + * and coherent type pages.
> + * This test makes use of gup_test module. Make sure GUP_TEST_CONFIG is added
> + * to your configuration before you run it.
> + */
> +TEST_F(hmm, hmm_gup_test)
> +{
> + struct hmm_buffer *buffer;
> + struct gup_test gup;
> + int gup_fd;
> + unsigned long npages;
> + unsigned long size;
> + unsigned long i;
> + int *ptr;
> + int ret;
> + unsigned char *m;
> +
> + gup_fd = open("/sys/kernel/debug/gup_test", O_RDWR);
> + if (gup_fd == -1)
> + SKIP(return, "Skipping test, could not find gup_test driver");
> +
> + npages = 4;
> + ASSERT_NE(npages, 0);
> + size = npages << self->page_shift;
> +
> + buffer = malloc(sizeof(*buffer));
> + ASSERT_NE(buffer, NULL);
> +
> + buffer->fd = -1;
> + buffer->size = size;
> + buffer->mirror = malloc(size);
> + ASSERT_NE(buffer->mirror, NULL);
> +
> + buffer->ptr = mmap(NULL, size,
> + PROT_READ | PROT_WRITE,
> + MAP_PRIVATE | MAP_ANONYMOUS,
> + buffer->fd, 0);
> + ASSERT_NE(buffer->ptr, MAP_FAILED);
> +
> + /* Initialize buffer in system memory. */
> + for (i = 0, ptr = buffer->ptr; i < size / sizeof(*ptr); ++i)
> + ptr[i] = i;
> +
> + /* Migrate memory to device. */
> + ret = hmm_migrate_sys_to_dev(self->fd, buffer, npages);
> + ASSERT_EQ(ret, 0);
> + ASSERT_EQ(buffer->cpages, npages);
> + /* Check what the device read. */
> + for (i = 0, ptr = buffer->mirror; i < size / sizeof(*ptr); ++i)
> + ASSERT_EQ(ptr[i], i);
> +
> + gup.nr_pages_per_call = npages;
> + gup.addr = (unsigned long)buffer->ptr;
> + gup.gup_flags = FOLL_WRITE;
> + gup.size = size;
> + /*
> + * Calling gup_test ioctl. It will try to PIN_LONGTERM these device pages
> + * causing a migration back to system memory for both, private and coherent
> + * type pages.
> + */
> + if (ioctl(gup_fd, PIN_LONGTERM_BENCHMARK, &gup)) {
> + perror("ioctl on PIN_LONGTERM_BENCHMARK\n");
> + goto out_test;
> + }
> +
> + /* Take snapshot to make sure pages have been migrated to sys memory */
> + ret = hmm_dmirror_cmd(self->fd, HMM_DMIRROR_SNAPSHOT, buffer, npages);
> + ASSERT_EQ(ret, 0);
> + ASSERT_EQ(buffer->cpages, npages);
> + m = buffer->mirror;
> + for (i = 0; i < npages; i++)
> + ASSERT_EQ(m[i], HMM_DMIRROR_PROT_WRITE);
> +out_test:
> + close(gup_fd);
> + hmm_buffer_free(buffer);
> +}
> TEST_HARNESS_MAIN