/*
 * Copyright © 2014 Intel Corporation
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice (including the next
 * paragraph) shall be included in all copies or substantial portions of the
 * Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 *
 */

#include "igt.h"
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <pthread.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/resource.h>

IGT_TEST_DESCRIPTION("Fill the Gobal GTT with context objects and VMs\n");

#define NUM_THREADS sysconf(_SC_NPROCESSORS_ONLN)

static void xchg_int(void *array, unsigned i, unsigned j)
{
	int *A = array;
	igt_swap(A[i], A[j]);
}

static unsigned get_num_contexts(int fd)
{
	uint64_t ggtt_size;
	unsigned size;
	unsigned count;

	/* Compute the number of contexts we can allocate to fill the GGTT */
	if (intel_gen(intel_get_drm_devid(fd)) >= 8)
		ggtt_size = 1ull << 32;
	else
		ggtt_size = 1ull << 31;

	size = 64 << 10; /* Most gen require at least 64k for ctx */

	count = 3 * (ggtt_size / size) / 2;
	igt_info("Creating %lld contexts (assuming of size %lld)\n",
		 (long long)count, (long long)size);

	intel_require_memory(count, size, CHECK_RAM | CHECK_SWAP);
	return count;
}

static int has_engine(int fd, const struct intel_execution_engine *e)
{
	uint32_t bbe = MI_BATCH_BUFFER_END;
	struct drm_i915_gem_execbuffer2 execbuf;
	struct drm_i915_gem_exec_object2 exec;
	int ret;

	memset(&exec, 0, sizeof(exec));
	exec.handle = gem_create(fd, 4096);
	gem_write(fd, exec.handle, 0, &bbe, sizeof(bbe));

	memset(&execbuf, 0, sizeof(execbuf));
	execbuf.buffers_ptr = (uintptr_t)&exec;
	execbuf.buffer_count = 1;
	execbuf.flags = e->exec_id | e->flags;
	ret = __gem_execbuf(fd, &execbuf);
	gem_close(fd, exec.handle);

	return ret == 0;
}

static void processes(void)
{
	const struct intel_execution_engine *e;
	unsigned engines[16];
	int num_engines;
	struct rlimit rlim;
	unsigned num_ctx;
	uint32_t name;
	int fd, *fds;

	fd = drm_open_driver(DRIVER_INTEL);
	num_ctx = get_num_contexts(fd);

	num_engines = 0;
	for (e = intel_execution_engines; e->name; e++) {
		if (e->exec_id == 0)
			continue;

		if (!has_engine(fd, e))
			continue;

		if (e->exec_id == I915_EXEC_BSD) {
			int is_bsd2 = e->flags != 0;
			if (gem_has_bsd2(fd) != is_bsd2)
				continue;
		}

		engines[num_engines++] = e->exec_id | e->flags;
		if (num_engines == ARRAY_SIZE(engines))
			break;
	}

	/* tweak rlimits to allow us to create this many files */
	igt_assert(getrlimit(RLIMIT_NOFILE, &rlim) == 0);
	if (rlim.rlim_cur < ALIGN(num_ctx + 1024, 1024)) {
		rlim.rlim_cur = ALIGN(num_ctx + 1024, 1024);
		if (rlim.rlim_cur > rlim.rlim_max)
			rlim.rlim_max = rlim.rlim_cur;
		igt_assert(setrlimit(RLIMIT_NOFILE, &rlim) == 0);
	}

	fds = malloc(num_ctx * sizeof(int));
	igt_assert(fds);
	for (unsigned n = 0; n < num_ctx; n++) {
		fds[n] = drm_open_driver(DRIVER_INTEL);
		if (fds[n] == -1) {
			int err = errno;
			for (unsigned i = n; i--; )
				close(fds[i]);
			free(fds);
			errno = err;
			igt_assert_f(0, "failed to create context %lld/%lld\n", (long long)n, (long long)num_ctx);
		}
	}

	if (1) {
		uint32_t bbe = MI_BATCH_BUFFER_END;
		name = gem_create(fd, 4096);
		gem_write(fd, name, 0, &bbe, sizeof(bbe));
		name = gem_flink(fd, name);
	}

	igt_fork(child, NUM_THREADS) {
		struct drm_i915_gem_execbuffer2 execbuf;
		struct drm_i915_gem_exec_object2 obj;

		memset(&obj, 0, sizeof(obj));
		memset(&execbuf, 0, sizeof(execbuf));
		execbuf.buffers_ptr = (uintptr_t)&obj;
		execbuf.buffer_count = 1;

		igt_permute_array(fds, num_ctx, xchg_int);
		for (unsigned n = 0; n < num_ctx; n++) {
			obj.handle = gem_open(fds[n], name);
			execbuf.flags = engines[n % num_engines];
			gem_execbuf(fds[n], &execbuf);
			gem_close(fds[n], obj.handle);
		}
	}
	igt_waitchildren();

	for (unsigned n = 0; n < num_ctx; n++)
		close(fds[n]);
	free(fds);
	close(fd);
}

struct thread {
	int fd;
	uint32_t *all_ctx;
	unsigned num_ctx;
};

static void *thread(void *data)
{
	struct thread *t = data;
	uint32_t bbe = MI_BATCH_BUFFER_END;
	struct drm_i915_gem_execbuffer2 execbuf;
	struct drm_i915_gem_exec_object2 obj;
	uint32_t *ctx;

	memset(&obj, 0, sizeof(obj));
	obj.handle = gem_create(t->fd, 4096);
	gem_write(t->fd, obj.handle, 0, &bbe, sizeof(bbe));

	memset(&execbuf, 0, sizeof(execbuf));
	execbuf.buffers_ptr = (uintptr_t)&obj;
	execbuf.buffer_count = 1;

	ctx = malloc(t->num_ctx * sizeof(uint32_t));
	igt_assert(ctx);
	memcpy(ctx, t->all_ctx, t->num_ctx * sizeof(uint32_t));
	igt_permute_array(ctx, t->num_ctx, xchg_int);

	for (unsigned n = 0; n < t->num_ctx; n++) {
		execbuf.rsvd1 = ctx[n];
		gem_execbuf(t->fd, &execbuf);
	}

	free(ctx);
	gem_close(t->fd, obj.handle);

	return NULL;
}

static void threads(void)
{
	pthread_t threads[NUM_THREADS];
	struct thread data;

	data.fd = drm_open_driver_render(DRIVER_INTEL);
	data.num_ctx = get_num_contexts(data.fd);
	data.all_ctx = malloc(data.num_ctx * sizeof(uint32_t));
	igt_assert(data.all_ctx);
	for (unsigned n = 0; n < data.num_ctx; n++)
		data.all_ctx[n] = gem_context_create(data.fd);

	for (int n = 0; n < NUM_THREADS; n++)
		pthread_create(&threads[n], NULL, thread, &data);

	for (int n = 0; n < NUM_THREADS; n++)
		pthread_join(threads[n], NULL);

	close(data.fd);
}

igt_main
{
	igt_skip_on_simulation();

	igt_subtest("processes")
		processes();

	igt_subtest("threads")
		threads();
}