[igt-dev] [PATCH 2/2] i915/perf: Add tests for mapped OA buffer
Umesh Nerlige Ramappa
umesh.nerlige.ramappa at intel.com
Thu Sep 24 16:26:09 UTC 2020
Following up, any reviewers?
Thanks,
Umesh
On Tue, Aug 18, 2020 at 01:35:47PM -0700, Umesh Nerlige Ramappa wrote:
>For applications that need a faster way to access reports in the OA
>buffer, i915 now provides a way to map the OA buffer to privileged user
>space. Validate the mapped OA buffer.
>
>v2: Fail on forked-privileged access to mapped oa buffer (Chris)
>
>Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa at intel.com>
>---
> include/drm-uapi/i915_drm.h | 18 +++
> tests/i915/perf.c | 295 ++++++++++++++++++++++++++++++++++++
> 2 files changed, 313 insertions(+)
>
>diff --git a/include/drm-uapi/i915_drm.h b/include/drm-uapi/i915_drm.h
>index ef696d1a..26c41c74 100644
>--- a/include/drm-uapi/i915_drm.h
>+++ b/include/drm-uapi/i915_drm.h
>@@ -2101,6 +2101,24 @@ struct drm_i915_perf_open_param {
> */
> #define I915_PERF_IOCTL_CONFIG _IO('i', 0x2)
>
>+/**
>+ * Returns OA buffer properties to be used with mmap.
>+ *
>+ * This ioctl is available in perf revision 8.
>+ */
>+#define I915_PERF_IOCTL_GET_OA_BUFFER_INFO _IOWR('i', 0x3, struct drm_i915_perf_oa_buffer_info)
>+
>+/**
>+ * OA buffer size and offset.
>+ */
>+struct drm_i915_perf_oa_buffer_info {
>+ __u32 type; /* in */
>+ __u32 flags; /* in */
>+ __u64 size; /* out */
>+ __u64 offset; /* out */
>+ __u64 rsvd; /* mbz */
>+};
>+
> /**
> * Common to all i915 perf records
> */
>diff --git a/tests/i915/perf.c b/tests/i915/perf.c
>index b030cfad..6af80484 100644
>--- a/tests/i915/perf.c
>+++ b/tests/i915/perf.c
>@@ -5172,6 +5172,271 @@ static void test_oa_regs_whitelist(int paranoid)
> intel_register_access_fini(&mmio_data);
> }
>
>+#define OA_BUFFER_DATA(tail, head, oa_buffer_size) \
>+ (((tail) - (head)) & ((oa_buffer_size) - 1))
>+
>+#ifndef MAP_FAILED
>+#define MAP_FAILED ((void *)-1)
>+#endif
>+
>+static uint32_t oa_status_reg(void)
>+{
>+ uint32_t status;
>+
>+ intel_register_access_init(&mmio_data, intel_get_pci_device(),
>+ 0, drm_fd);
>+ if (IS_HASWELL(devid))
>+ status = intel_register_read(&mmio_data, 0x2346) & 0x7;
>+ else if (IS_GEN12(devid))
>+ status = intel_register_read(&mmio_data, 0xdafc) & 0x7;
>+ else
>+ status = intel_register_read(&mmio_data, 0x2b08) & 0xf;
>+
>+ intel_register_access_fini(&mmio_data);
>+
>+ return status;
>+}
>+
>+static jmp_buf jmp;
>+static void __attribute__((noreturn)) sigtrap(int sig)
>+{
>+ siglongjmp(jmp, sig);
>+}
>+
>+static void try_invalid_access(void *vaddr)
>+{
>+ sighandler_t old_sigsegv;
>+ uint32_t dummy;
>+
>+ old_sigsegv = signal(SIGSEGV, sigtrap);
>+ switch (sigsetjmp(jmp, SIGSEGV)) {
>+ case SIGSEGV:
>+ break;
>+ case 0:
>+ dummy = READ_ONCE(*((uint32_t *)vaddr + 1));
>+ (void) dummy;
>+ default:
>+ igt_assert(!"reached");
>+ break;
>+ }
>+ signal(SIGSEGV, old_sigsegv);
>+}
>+
>+static void invalid_param_map_oa_buffer(void)
>+{
>+ struct drm_i915_perf_oa_buffer_info oa_buffer = { 0 };
>+ void *oa_vaddr = NULL;
>+
>+ do_ioctl(stream_fd, I915_PERF_IOCTL_GET_OA_BUFFER_INFO, &oa_buffer);
>+
>+ igt_debug("size = %llu\n", oa_buffer.size);
>+ igt_debug("offset = %llx\n", oa_buffer.offset);
>+
>+ igt_assert_eq(oa_buffer.size & (oa_buffer.size - 1), 0);
>+
>+ /* try a couple invalid mmaps */
>+ /* bad prots */
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_WRITE, MAP_PRIVATE, stream_fd, oa_buffer.offset);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_EXEC, MAP_PRIVATE, stream_fd, oa_buffer.offset);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ /* bad MAPs */
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_SHARED, stream_fd, oa_buffer.offset);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ /* bad offsets */
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_PRIVATE, stream_fd, 0);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_PRIVATE, stream_fd, 8192);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_PRIVATE, stream_fd, 11);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ /* bad size */
>+ oa_vaddr = mmap(0, oa_buffer.size + 1, PROT_READ, MAP_PRIVATE, stream_fd, oa_buffer.offset);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+
>+ /* do the right thing */
>+ oa_vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_PRIVATE, stream_fd, oa_buffer.offset);
>+ igt_assert(oa_vaddr != MAP_FAILED && oa_vaddr != NULL);
>+
>+ munmap(oa_vaddr, oa_buffer.size);
>+}
>+
>+static void *map_oa_buffer(uint32_t *size)
>+{
>+ struct drm_i915_perf_oa_buffer_info oa_buffer = { 0 };
>+ void *vaddr;
>+
>+ do_ioctl(stream_fd, I915_PERF_IOCTL_GET_OA_BUFFER_INFO, &oa_buffer);
>+
>+ igt_debug("size = %llu\n", oa_buffer.size);
>+ igt_debug("offset = %llx\n", oa_buffer.offset);
>+
>+ igt_assert_eq(oa_buffer.size & (oa_buffer.size - 1), 0);
>+ igt_assert_eq(oa_status_reg(), 0);
>+
>+ vaddr = mmap(0, oa_buffer.size, PROT_READ, MAP_PRIVATE, stream_fd, oa_buffer.offset);
>+ igt_assert(vaddr != NULL);
>+
>+ *size = oa_buffer.size;
>+
>+ return vaddr;
>+}
>+
>+static void unmap_oa_buffer(void *addr, uint32_t size)
>+{
>+ munmap(addr, size);
>+}
>+
>+static void check_reports(void *oa_vaddr, uint32_t oa_size)
>+{
>+ struct oa_format format = get_oa_format(test_set->perf_oa_format);
>+ size_t report_words = format.size >> 2;
>+ uint32_t *reports;
>+ uint32_t timer_reports = 0;
>+
>+ for (reports = (uint32_t *)oa_vaddr;
>+ timer_reports < 20 && reports[0] && reports[1];
>+ reports += report_words) {
>+ if (!oa_report_is_periodic(oa_exp_1_millisec, reports))
>+ continue;
>+
>+ timer_reports++;
>+ if (timer_reports >= 3)
>+ sanity_check_reports(reports - 2 * report_words,
>+ reports - report_words,
>+ test_set->perf_oa_format);
>+ }
>+
>+ igt_assert(timer_reports >= 3);
>+}
>+
>+static void check_reports_from_mapped_buffer(void)
>+{
>+ void *vaddr;
>+ uint32_t size;
>+ uint32_t period_us = oa_exponent_to_ns(oa_exp_1_millisec) / 1000;
>+
>+ vaddr = map_oa_buffer(&size);
>+
>+ /* wait for approx 100 reports */
>+ usleep(100 * period_us);
>+ check_reports(vaddr, size);
>+
>+ unmap_oa_buffer(vaddr, size);
>+}
>+
>+static void unprivileged_try_to_map_oa_buffer(void)
>+{
>+ struct drm_i915_perf_oa_buffer_info oa_buffer = { 0 };
>+ void *oa_vaddr;
>+
>+ do_ioctl_err(stream_fd, I915_PERF_IOCTL_GET_OA_BUFFER_INFO,
>+ &oa_buffer, EACCES);
>+
>+ oa_vaddr = mmap(0, 4096, PROT_READ, MAP_PRIVATE, stream_fd, 4096);
>+ igt_assert(oa_vaddr == MAP_FAILED);
>+ igt_assert_eq(errno, EACCES);
>+}
>+
>+static void unprivileged_map_oa_buffer(void)
>+{
>+ igt_fork(child, 1) {
>+ igt_drop_root();
>+ unprivileged_try_to_map_oa_buffer();
>+ }
>+ igt_waitchildren();
>+}
>+
>+static void map_oa_buffer_unprivilege_access(void)
>+{
>+ void *vaddr;
>+ uint32_t size;
>+
>+ vaddr = map_oa_buffer(&size);
>+
>+ igt_fork(child, 1) {
>+ igt_drop_root();
>+ try_invalid_access(vaddr);
>+ }
>+ igt_waitchildren();
>+
>+ unmap_oa_buffer(vaddr, size);
>+}
>+
>+static void map_oa_buffer_forked_access(void)
>+{
>+ void *vaddr;
>+ uint32_t size;
>+
>+ vaddr = map_oa_buffer(&size);
>+
>+ igt_fork(child, 1) {
>+ try_invalid_access(vaddr);
>+ }
>+ igt_waitchildren();
>+
>+ unmap_oa_buffer(vaddr, size);
>+}
>+
>+static void test_mapped_oa_buffer(void (*test_with_fd_open)(void))
>+{
>+ uint64_t properties[] = {
>+ DRM_I915_PERF_PROP_SAMPLE_OA, true,
>+ DRM_I915_PERF_PROP_OA_METRICS_SET, test_set->perf_oa_metrics_set,
>+ DRM_I915_PERF_PROP_OA_FORMAT, test_set->perf_oa_format,
>+ DRM_I915_PERF_PROP_OA_EXPONENT, oa_exp_1_millisec,
>+
>+ };
>+ struct drm_i915_perf_open_param param = {
>+ .flags = I915_PERF_FLAG_FD_CLOEXEC,
>+ .num_properties = sizeof(properties) / 16,
>+ .properties_ptr = to_user_pointer(properties),
>+ };
>+
>+ stream_fd = __perf_open(drm_fd, ¶m, false);
>+
>+ igt_assert(test_with_fd_open);
>+ test_with_fd_open();
>+
>+ __perf_close(stream_fd);
>+}
>+
>+static void closed_fd_and_unmapped_access(void)
>+{
>+ uint64_t properties[] = {
>+ DRM_I915_PERF_PROP_SAMPLE_OA, true,
>+ DRM_I915_PERF_PROP_OA_METRICS_SET, test_set->perf_oa_metrics_set,
>+ DRM_I915_PERF_PROP_OA_FORMAT, test_set->perf_oa_format,
>+ DRM_I915_PERF_PROP_OA_EXPONENT, oa_exp_1_millisec,
>+
>+ };
>+ struct drm_i915_perf_open_param param = {
>+ .flags = I915_PERF_FLAG_FD_CLOEXEC,
>+ .num_properties = sizeof(properties) / 16,
>+ .properties_ptr = to_user_pointer(properties),
>+ };
>+ void *vaddr;
>+ uint32_t size;
>+ uint32_t period_us = oa_exponent_to_ns(oa_exp_1_millisec) / 1000;
>+
>+ stream_fd = __perf_open(drm_fd, ¶m, false);
>+ vaddr = map_oa_buffer(&size);
>+
>+ usleep(100 * period_us);
>+ check_reports(vaddr, size);
>+
>+ unmap_oa_buffer(vaddr, size);
>+ __perf_close(stream_fd);
>+
>+ try_invalid_access(vaddr);
>+}
>+
> static unsigned
> read_i915_module_ref(void)
> {
>@@ -5507,6 +5772,36 @@ igt_main
> test_triggered_oa_reports(1);
> }
>
>+ igt_subtest_group {
>+ igt_fixture {
>+ igt_require(i915_perf_revision(drm_fd) >= 8);
>+ }
>+
>+ igt_describe("Verify mapping of oa buffer");
>+ igt_subtest("map-oa-buffer")
>+ test_mapped_oa_buffer(check_reports_from_mapped_buffer);
>+
>+ igt_describe("Verify invalid mappings of oa buffer");
>+ igt_subtest("invalid-map-oa-buffer")
>+ test_mapped_oa_buffer(invalid_param_map_oa_buffer);
>+
>+ igt_describe("Verify if non-privileged user can map oa buffer");
>+ igt_subtest("non-privileged-map-oa-buffer")
>+ test_mapped_oa_buffer(unprivileged_map_oa_buffer);
>+
>+ igt_describe("Verify if non-privileged user can map oa buffer");
>+ igt_subtest("non-privileged-access-vaddr")
>+ test_mapped_oa_buffer(map_oa_buffer_unprivilege_access);
>+
>+ igt_describe("Verify that forked access to mapped buffer fails");
>+ igt_subtest("privileged-forked-access-vaddr")
>+ test_mapped_oa_buffer(map_oa_buffer_forked_access);
>+
>+ igt_describe("Unmap buffer, close fd and try to access");
>+ igt_subtest("closed-fd-and-unmapped-access")
>+ closed_fd_and_unmapped_access();
>+ }
>+
> igt_fixture {
> /* leave sysctl options in their default state... */
> write_u64_file("/proc/sys/dev/i915/oa_max_sample_rate", 100000);
>--
>2.20.1
>
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