On Wed, May 19, 2021 at 1:03 PM Axel Rasmussen <axelrasmussen@xxxxxxxxxx> wrote:
>
> A small cleanup. Our caller writes:
>
> r = setup_demand_paging(...);
> if (r < 0) exit(-r);
>
> Since we're just going to exit anyway, instead of returning an error we
> can just re-use TEST_ASSERT. This makes the caller simpler, as well as
> the function itself - no need to write our branches, etc.
>
> Signed-off-by: Axel Rasmussen <axelrasmussen@xxxxxxxxxx>
> ---
> .../selftests/kvm/demand_paging_test.c | 51 +++++++------------
> 1 file changed, 19 insertions(+), 32 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/demand_paging_test.c b/tools/testing/selftests/kvm/demand_paging_test.c
> index 9398ba6ef023..601a1df24dd2 100644
> --- a/tools/testing/selftests/kvm/demand_paging_test.c
> +++ b/tools/testing/selftests/kvm/demand_paging_test.c
> @@ -9,6 +9,8 @@
>
> #define _GNU_SOURCE /* for pipe2 */
>
> +#include <inttypes.h>
> +#include <stdint.h>
Why do the includes need to change in this commit? Is it for the PRIu64 below?
> #include <stdio.h>
> #include <stdlib.h>
> #include <time.h>
> @@ -198,42 +200,32 @@ static void *uffd_handler_thread_fn(void *arg)
> return NULL;
> }
>
> -static int setup_demand_paging(struct kvm_vm *vm,
> - pthread_t *uffd_handler_thread, int pipefd,
> - useconds_t uffd_delay,
> - struct uffd_handler_args *uffd_args,
> - void *hva, uint64_t len)
> +static void setup_demand_paging(struct kvm_vm *vm,
> + pthread_t *uffd_handler_thread, int pipefd,
> + useconds_t uffd_delay,
> + struct uffd_handler_args *uffd_args,
> + void *hva, uint64_t len)
> {
> int uffd;
> struct uffdio_api uffdio_api;
> struct uffdio_register uffdio_register;
>
> uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK);
> - if (uffd == -1) {
> - pr_info("uffd creation failed\n");
> - return -1;
> - }
> + TEST_ASSERT(uffd >= 0, "uffd creation failed, errno: %d", errno);
>
> uffdio_api.api = UFFD_API;
> uffdio_api.features = 0;
> - if (ioctl(uffd, UFFDIO_API, &uffdio_api) == -1) {
> - pr_info("ioctl uffdio_api failed\n");
> - return -1;
> - }
> + TEST_ASSERT(ioctl(uffd, UFFDIO_API, &uffdio_api) != -1,
> + "ioctl UFFDIO_API failed: %" PRIu64,
> + (uint64_t)uffdio_api.api);
>
> uffdio_register.range.start = (uint64_t)hva;
> uffdio_register.range.len = len;
> uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING;
> - if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) == -1) {
> - pr_info("ioctl uffdio_register failed\n");
> - return -1;
> - }
> -
> - if ((uffdio_register.ioctls & UFFD_API_RANGE_IOCTLS) !=
> - UFFD_API_RANGE_IOCTLS) {
> - pr_info("unexpected userfaultfd ioctl set\n");
> - return -1;
> - }
> + TEST_ASSERT(ioctl(uffd, UFFDIO_REGISTER, &uffdio_register) != -1,
> + "ioctl UFFDIO_REGISTER failed");
> + TEST_ASSERT((uffdio_register.ioctls & UFFD_API_RANGE_IOCTLS) ==
> + UFFD_API_RANGE_IOCTLS, "unexpected userfaultfd ioctl set");
>
> uffd_args->uffd = uffd;
> uffd_args->pipefd = pipefd;
> @@ -243,8 +235,6 @@ static int setup_demand_paging(struct kvm_vm *vm,
>
> PER_VCPU_DEBUG("Created uffd thread for HVA range [%p, %p)\n",
> hva, hva + len);
> -
> - return 0;
> }
>
> struct test_params {
> @@ -321,13 +311,10 @@ static void run_test(enum vm_guest_mode mode, void *arg)
> O_CLOEXEC | O_NONBLOCK);
> TEST_ASSERT(!r, "Failed to set up pipefd");
>
> - r = setup_demand_paging(vm,
> - &uffd_handler_threads[vcpu_id],
> - pipefds[vcpu_id * 2],
> - p->uffd_delay, &uffd_args[vcpu_id],
> - vcpu_hva, vcpu_mem_size);
> - if (r < 0)
> - exit(-r);
> + setup_demand_paging(vm, &uffd_handler_threads[vcpu_id],
> + pipefds[vcpu_id * 2], p->uffd_delay,
> + &uffd_args[vcpu_id], vcpu_hva,
> + vcpu_mem_size);
> }
> }
>
> --
> 2.31.1.751.gd2f1c929bd-goog
>
