[PATCH 4/7] drm/i915: Track all user contexts per client

[Tvrtko Ursulin]

From: Tvrtko Ursulin <tvrtko.ursu...@intel.com>

We soon want to start answering questions like how much GPU time is the
context belonging to a client which exited still using.

To enable this we start tracking all context belonging to a client on a
separate list.

Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@intel.com>
Reviewed-by: Aravind Iddamsetty <aravind.iddamse...@intel.com>
Reviewed-by: Chris Wilson <ch...@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <ch...@chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/gem/i915_gem_context.c       | 12 ++++++++++++
 drivers/gpu/drm/i915/gem/i915_gem_context_types.h |  3 +++
 drivers/gpu/drm/i915/i915_drm_client.c            |  2 ++
 drivers/gpu/drm/i915/i915_drm_client.h            |  5 +++++
 4 files changed, 22 insertions(+)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c 
b/drivers/gpu/drm/i915/gem/i915_gem_context.c
index 9b37723b70a9..a1ef6be28899 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c
@@ -1190,6 +1190,7 @@ static void set_closed_name(struct i915_gem_context *ctx)
 
 static void context_close(struct i915_gem_context *ctx)
 {
+       struct i915_drm_client *client;
        struct i915_address_space *vm;
 
        /* Flush any concurrent set_engines() */
@@ -1226,6 +1227,13 @@ static void context_close(struct i915_gem_context *ctx)
        list_del(&ctx->link);
        spin_unlock(&ctx->i915->gem.contexts.lock);
 
+       client = ctx->client;
+       if (client) {
+               spin_lock(&client->ctx_lock);
+               list_del_rcu(&ctx->client_link);
+               spin_unlock(&client->ctx_lock);
+       }
+
        mutex_unlock(&ctx->mutex);
 
        /*
@@ -1406,6 +1414,10 @@ static void gem_context_register(struct i915_gem_context 
*ctx,
        old = xa_store(&fpriv->context_xa, id, ctx, GFP_KERNEL);
        WARN_ON(old);
 
+       spin_lock(&ctx->client->ctx_lock);
+       list_add_tail_rcu(&ctx->client_link, &ctx->client->ctx_list);
+       spin_unlock(&ctx->client->ctx_lock);
+
        spin_lock(&i915->gem.contexts.lock);
        list_add_tail(&ctx->link, &i915->gem.contexts.list);
        spin_unlock(&i915->gem.contexts.lock);
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h 
b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
index 598c57ac5cdf..b878e1b13b38 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
+++ b/drivers/gpu/drm/i915/gem/i915_gem_context_types.h
@@ -280,6 +280,9 @@ struct i915_gem_context {
        /** @client: struct i915_drm_client */
        struct i915_drm_client *client;
 
+       /** link: &drm_client.context_list */
+       struct list_head client_link;
+
        /**
         * @ref: reference count
         *
diff --git a/drivers/gpu/drm/i915/i915_drm_client.c 
b/drivers/gpu/drm/i915/i915_drm_client.c
index e61e9ba15256..91a8559bebf7 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.c
+++ b/drivers/gpu/drm/i915/i915_drm_client.c
@@ -38,6 +38,8 @@ struct i915_drm_client *i915_drm_client_add(struct 
i915_drm_clients *clients)
                goto err;
 
        kref_init(&client->kref);
+       spin_lock_init(&client->ctx_lock);
+       INIT_LIST_HEAD(&client->ctx_list);
        client->clients = clients;
 
        return client;
diff --git a/drivers/gpu/drm/i915/i915_drm_client.h 
b/drivers/gpu/drm/i915/i915_drm_client.h
index 9d80d9f715ee..7416e18aa33c 100644
--- a/drivers/gpu/drm/i915/i915_drm_client.h
+++ b/drivers/gpu/drm/i915/i915_drm_client.h
@@ -7,6 +7,8 @@
 #define __I915_DRM_CLIENT_H__
 
 #include <linux/kref.h>
+#include <linux/list.h>
+#include <linux/spinlock.h>
 #include <linux/xarray.h>
 
 #include "gt/intel_engine_types.h"
@@ -25,6 +27,9 @@ struct i915_drm_client {
 
        unsigned int id;
 
+       spinlock_t ctx_lock; /* For add/remove from ctx_list. */
+       struct list_head ctx_list; /* List of contexts belonging to client. */
+
        struct i915_drm_clients *clients;
 
        /**
-- 
2.30.2