[igt-dev] [PATCH i-g-t] tests/i915/perf_pmu: PCI unbind test

[Chris Wilson]

Quoting Tvrtko Ursulin (2020-10-20 17:14:01)
> From: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> 
> Test driver unbind from device with active PMU client.
> 
> Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>  tests/i915/perf_pmu.c | 108 ++++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 108 insertions(+)
> 
> diff --git a/tests/i915/perf_pmu.c b/tests/i915/perf_pmu.c
> index cb7273142b8f..b2402955092e 100644
> --- a/tests/i915/perf_pmu.c
> +++ b/tests/i915/perf_pmu.c
> @@ -43,6 +43,7 @@
>  #include "igt.h"
>  #include "igt_core.h"
>  #include "igt_device.h"
> +#include "igt_device_scan.h"
>  #include "igt_kmod.h"
>  #include "igt_perf.h"
>  #include "igt_sysfs.h"
> @@ -2011,6 +2012,75 @@ static void test_unload(unsigned int num_engines)
>         igt_assert_eq(unload_i915(), 0);
>  }
>  
> +static void set_filter_from_device(int fd)
> +{
> +       const char *filter_type = "sys:";
> +       char filter[strlen(filter_type) + PATH_MAX + 1];
> +       char *dst = stpcpy(filter, filter_type);
> +       char path[PATH_MAX + 1];
> +
> +       igt_assert(igt_sysfs_path(fd, path, PATH_MAX));
> +       igt_ignore_warn(strncat(path, "/device", PATH_MAX - strlen(path)));
> +       igt_assert(realpath(path, dst));
> +
> +       igt_device_filter_free_all();
> +       igt_assert_eq(igt_device_filter_add(filter), 1);
> +}
> +
> +struct rebind_data
> +{
> +       int sysfs;
> +       uint64_t perf_type;
> +       char *bus_addr;
> +};
> +
> +static void test_rebind(struct rebind_data *data)
> +{
> +       struct igt_helper_process pmu_client = { };
> +       const unsigned int timeout = 5;
> +       int pmu;
> +
> +       /* Start rapid PMU traffic from a background process. */
> +       igt_fork_helper(&pmu_client) {
> +               pmu = igt_perf_open(data->perf_type, I915_PMU_INTERRUPTS);
> +               igt_assert(pmu >= 0);
> +
> +               for (;;) {
> +                       pmu_read_single(pmu);
> +                       usleep(500);
> +               }
> +       }
> +
> +       /* Let the child run for a bit. */
> +       usleep(1e6);
> +
> +       /* Unbind the device. */
> +       igt_set_timeout(timeout, "Driver unbind timeout!");
> +       igt_assert_f(igt_sysfs_set(data->sysfs, "unbind", data->bus_addr),
> +                    "Driver unbind failure!\n");
> +       igt_reset_timeout();
> +
> +       /* Check new PMUs cannot be opened. */
> +       pmu = igt_perf_open(data->perf_type, I915_PMU_INTERRUPTS);
> +       igt_assert(pmu < 0);
> +       usleep(1e6);
> +       pmu = igt_perf_open(data->perf_type, I915_PMU_INTERRUPTS);
> +       igt_assert(pmu < 0);
> +
> +       /* Stop background PMU traffic. */
> +       usleep(1e6);
> +       igt_stop_helper(&pmu_client);
> +
> +       /* Bind the device back. */
> +       igt_set_timeout(timeout, "Driver bind timeout!");
> +       igt_assert_f(igt_sysfs_set(data->sysfs, "bind", data->bus_addr),
> +                    "Driver bind failure\n!");
> +       igt_reset_timeout();
> +
> +       igt_fail_on_f(faccessat(data->sysfs, data->bus_addr, F_OK, 0),
> +                     "Device not present!\n");

Then check we can now igt_perf_open(data->perf_type, I915_PMU_INTERRUPTS);
again?
-Chris