// SPDX-License-Identifier: MIT
/*
 * Copyright © 2020 Intel Corporation
 */

#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/types.h>

#include <uapi/drm/i915_drm.h>

#include <drm/drm_print.h>

#include "gem/i915_gem_context.h"
#include "i915_drm_client.h"
#include "i915_file_private.h"
#include "i915_gem.h"
#include "i915_utils.h"

struct i915_drm_client *i915_drm_client_alloc(void)
{
        struct i915_drm_client *client;

        client = kzalloc(sizeof(*client), GFP_KERNEL);
        if (!client)
                return NULL;

        kref_init(&client->kref);
        mtx_init(&client->ctx_lock, IPL_NONE);
        INIT_LIST_HEAD(&client->ctx_list);
#ifdef CONFIG_PROC_FS
        spin_lock_init(&client->objects_lock);
        INIT_LIST_HEAD(&client->objects_list);
#endif

        return client;
}

void __i915_drm_client_free(struct kref *kref)
{
        struct i915_drm_client *client =
                container_of(kref, typeof(*client), kref);

        kfree(client);
}

#ifdef CONFIG_PROC_FS
static void
obj_meminfo(struct drm_i915_gem_object *obj,
            struct drm_memory_stats stats[INTEL_REGION_UNKNOWN])
{
        const enum intel_region_id id = obj->mm.region ?
                                        obj->mm.region->id : INTEL_REGION_SMEM;
        const u64 sz = obj->base.size;

        if (drm_gem_object_is_shared_for_memory_stats(&obj->base))
                stats[id].shared += sz;
        else
                stats[id].private += sz;

        if (i915_gem_object_has_pages(obj)) {
                stats[id].resident += sz;

                if (!dma_resv_test_signaled(obj->base.resv,
                                            DMA_RESV_USAGE_BOOKKEEP))
                        stats[id].active += sz;
                else if (i915_gem_object_is_shrinkable(obj) &&
                         obj->mm.madv == I915_MADV_DONTNEED)
                        stats[id].purgeable += sz;
        }
}

static void show_meminfo(struct drm_printer *p, struct drm_file *file)
{
        struct drm_memory_stats stats[INTEL_REGION_UNKNOWN] = {};
        struct drm_i915_file_private *fpriv = file->driver_priv;
        struct i915_drm_client *client = fpriv->client;
        struct drm_i915_private *i915 = fpriv->i915;
        struct drm_i915_gem_object *obj;
        struct intel_memory_region *mr;
        struct list_head __rcu *pos;
        unsigned int id;

        /* Public objects. */
        spin_lock(&file->table_lock);
        idr_for_each_entry(&file->object_idr, obj, id)
                obj_meminfo(obj, stats);
        spin_unlock(&file->table_lock);

        /* Internal objects. */
        rcu_read_lock();
        list_for_each_rcu(pos, &client->objects_list) {
                obj = i915_gem_object_get_rcu(list_entry(pos, typeof(*obj),
                                                         client_link));
                if (!obj)
                        continue;
                obj_meminfo(obj, stats);
                i915_gem_object_put(obj);
        }
        rcu_read_unlock();

        for_each_memory_region(mr, i915, id)
                drm_print_memory_stats(p,
                                       &stats[id],
                                       DRM_GEM_OBJECT_ACTIVE |
                                       DRM_GEM_OBJECT_RESIDENT |
                                       DRM_GEM_OBJECT_PURGEABLE,
                                       mr->uabi_name);
}

static const char * const uabi_class_names[] = {
        [I915_ENGINE_CLASS_RENDER] = "render",
        [I915_ENGINE_CLASS_COPY] = "copy",
        [I915_ENGINE_CLASS_VIDEO] = "video",
        [I915_ENGINE_CLASS_VIDEO_ENHANCE] = "video-enhance",
        [I915_ENGINE_CLASS_COMPUTE] = "compute",
};

static u64 busy_add(struct i915_gem_context *ctx, unsigned int class)
{
        struct i915_gem_engines_iter it;
        struct intel_context *ce;
        u64 total = 0;

        for_each_gem_engine(ce, rcu_dereference(ctx->engines), it) {
                if (ce->engine->uabi_class != class)
                        continue;

                total += intel_context_get_total_runtime_ns(ce);
        }

        return total;
}

static void
show_client_class(struct drm_printer *p,
                  struct drm_i915_private *i915,
                  struct i915_drm_client *client,
                  unsigned int class)
{
        const unsigned int capacity = i915->engine_uabi_class_count[class];
        u64 total = atomic64_read(&client->past_runtime[class]);
        struct i915_gem_context *ctx;

        rcu_read_lock();
        list_for_each_entry_rcu(ctx, &client->ctx_list, client_link)
                total += busy_add(ctx, class);
        rcu_read_unlock();

        if (capacity)
                drm_printf(p, "drm-engine-%s:\t%llu ns\n",
                           uabi_class_names[class], total);

        if (capacity > 1)
                drm_printf(p, "drm-engine-capacity-%s:\t%u\n",
                           uabi_class_names[class],
                           capacity);
}

void i915_drm_client_fdinfo(struct drm_printer *p, struct drm_file *file)
{
        struct drm_i915_file_private *file_priv = file->driver_priv;
        struct drm_i915_private *i915 = file_priv->i915;
        unsigned int i;

        /*
         * ******************************************************************
         * For text output format description please see drm-usage-stats.rst!
         * ******************************************************************
         */

        show_meminfo(p, file);

        if (GRAPHICS_VER(i915) < 8)
                return;

        for (i = 0; i < ARRAY_SIZE(uabi_class_names); i++)
                show_client_class(p, i915, file_priv->client, i);
}

void i915_drm_client_add_object(struct i915_drm_client *client,
                                struct drm_i915_gem_object *obj)
{
        unsigned long flags;

        GEM_WARN_ON(obj->client);
        GEM_WARN_ON(!list_empty(&obj->client_link));

        spin_lock_irqsave(&client->objects_lock, flags);
        obj->client = i915_drm_client_get(client);
        list_add_tail_rcu(&obj->client_link, &client->objects_list);
        spin_unlock_irqrestore(&client->objects_lock, flags);
}

void i915_drm_client_remove_object(struct drm_i915_gem_object *obj)
{
        struct i915_drm_client *client = fetch_and_zero(&obj->client);
        unsigned long flags;

        /* Object may not be associated with a client. */
        if (!client)
                return;

        spin_lock_irqsave(&client->objects_lock, flags);
        list_del_rcu(&obj->client_link);
        spin_unlock_irqrestore(&client->objects_lock, flags);

        i915_drm_client_put(client);
}

void i915_drm_client_add_context_objects(struct i915_drm_client *client,
                                         struct intel_context *ce)
{
        if (ce->state)
                i915_drm_client_add_object(client, ce->state->obj);

        if (ce->ring != ce->engine->legacy.ring && ce->ring->vma)
                i915_drm_client_add_object(client, ce->ring->vma->obj);
}
#endif