Re: [PATCH i-g-t 10/16] i915/gem_exec_whisper: Fork all-engine tests one-per-engine

Tvrtko Ursulin
2019-05-14T12:57:26Z

On 08/05/2019 11:09, Chris Wilson wrote:
> Add a new mode for some more stress, submit the all-engines tests
> simultaneously, a stream per engine.
>
> Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
> ---
> tests/i915/gem_exec_whisper.c | 27 ++++++++++++++++++++++-----
> 1 file changed, 22 insertions(+), 5 deletions(-)
>
> diff --git a/tests/i915/gem_exec_whisper.c b/tests/i915/gem_exec_whisper.c
> index d3e0b0ba2..d5afc8119 100644
> --- a/tests/i915/gem_exec_whisper.c
> +++ b/tests/i915/gem_exec_whisper.c
> @@ -88,6 +88,7 @@ static void verify_reloc(int fd, uint32_t handle,
> #define SYNC 0x40
> #define PRIORITY 0x80
> #define QUEUES 0x100
> +#define ALL 0x200
>
> struct hang {
> struct drm_i915_gem_exec_object2 obj;
> @@ -199,6 +200,7 @@ static void whisper(int fd, unsigned engine, unsigned flags)
> uint64_t old_offset;
> int i, n, loc;
> int debugfs;
> + int nchild;
>
> if (flags & PRIORITY) {
> igt_require(gem_scheduler_enabled(fd));
> @@ -215,6 +217,7 @@ static void whisper(int fd, unsigned engine, unsigned flags)
> engines[nengine++] = engine;
> }
> } else {
> + igt_assert(!(flags & ALL));
> igt_require(gem_has_ring(fd, engine));
> igt_require(gem_can_store_dword(fd, engine));
> engines[nengine++] = engine;
> @@ -233,11 +236,22 @@ static void whisper(int fd, unsigned engine, unsigned flags)
> if (flags & HANG)
> init_hang(&hang);
>
> + nchild = 1;
> + if (flags & FORKED)
> + nchild *= sysconf(_SC_NPROCESSORS_ONLN);
> + if (flags & ALL)
> + nchild *= nengine;
> +
> intel_detect_and_clear_missed_interrupts(fd);
> gpu_power_read(&power, &sample[0]);
> - igt_fork(child, flags & FORKED ? sysconf(_SC_NPROCESSORS_ONLN) : 1) {
> + igt_fork(child, nchild) {
> unsigned int pass;
>
> + if (flags & ALL) {
> + engines[0] = engines[child % nengine];

Relying on PIDs being sequential feels fragile but suggesting pipes or
shared memory would be overkill. How about another loop:

if (flags & ALL) {
for (i = 0; i < nchild; i++) {
engines_copy = engines;
nengines_copy = nengine;
negines_child = 1;
engines[0] = engines[i];
igt_fork(child, 1) {
...
}

if (in_parent) {
engines = engines_copy;
nengine = nengines_copy;
} else {
break;
}
}
}

?

Regards,

Tvrtko

> + nengine = 1;
> + }
> +
> memset(&scratch, 0, sizeof(scratch));
> scratch.handle = gem_create(fd, 4096);
> scratch.flags = EXEC_OBJECT_WRITE;
> @@ -341,7 +355,7 @@ static void whisper(int fd, unsigned engine, unsigned flags)
> igt_until_timeout(150) {
> uint64_t offset;
>
> - if (!(flags & FORKED))
> + if (nchild == 1)
> write_seqno(debugfs, pass);
>
> if (flags & HANG)
> @@ -382,8 +396,8 @@ static void whisper(int fd, unsigned engine, unsigned flags)
>
> gem_write(fd, batches[1023].handle, loc, &pass, sizeof(pass));
> for (n = 1024; --n >= 1; ) {
> + uint32_t handle[2] = {};
> int this_fd = fd;
> - uint32_t handle[2];
>
> execbuf.buffers_ptr = to_user_pointer(&batches[n-1]);
> reloc_migrations += batches[n-1].offset != inter[n].presumed_offset;
> @@ -550,7 +564,7 @@ igt_main
> { "queues-sync", QUEUES | SYNC },
> { NULL }
> };
> - int fd;
> + int fd = -1;
>
> igt_fixture {
> fd = drm_open_driver_master(DRIVER_INTEL);
> @@ -561,9 +575,12 @@ igt_main
> igt_fork_hang_detector(fd);
> }
>
> - for (const struct mode *m = modes; m->name; m++)
> + for (const struct mode *m = modes; m->name; m++) {
> igt_subtest_f("%s", m->name)
> whisper(fd, ALL_ENGINES, m->flags);
> + igt_subtest_f("%s-all", m->name)
> + whisper(fd, ALL_ENGINES, m->flags | ALL);
> + }
>
> for (const struct intel_execution_engine *e = intel_execution_engines;
> e->name; e++) {