diff mbox

drm/atomic: Allow for holes in connector state.

Message ID 1455542221-4848-1-git-send-email-maarten.lankhorst@linux.intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Maarten Lankhorst Feb. 15, 2016, 1:17 p.m. UTC
Because we record connector_mask using 1 << drm_connector_index now
the connector_mask should stay the same even when other connectors
are removed. This was not the case with MST, in that case when removing
a connector all other connectors may change their index.

This is fixed by waiting until the first get_connector_state to allocate
connector_state, and force reallocation when state is too small.

As a side effect connector arrays no longer have to be preallocated,
and can be allocated on first use which means a less allocations in
the page flip only path.

Fixes: 14de6c44d149 ("drm/atomic: Remove drm_atomic_connectors_for_crtc.")
Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
---
 drivers/gpu/drm/drm_atomic.c        | 45 +++++++++++++++++--------------------
 drivers/gpu/drm/drm_atomic_helper.c |  2 +-
 drivers/gpu/drm/drm_crtc.c          | 45 +++++++++++++------------------------
 include/drm/drm_crtc.h              |  8 ++++++-
 4 files changed, 45 insertions(+), 55 deletions(-)

Comments

kernel test robot Feb. 15, 2016, 2:30 p.m. UTC | #1
Hi Maarten,

[auto build test WARNING on drm/drm-next]
[also build test WARNING on v4.5-rc4 next-20160215]
[if your patch is applied to the wrong git tree, please drop us a note to help improving the system]

url:    https://github.com/0day-ci/linux/commits/Maarten-Lankhorst/drm-atomic-Allow-for-holes-in-connector-state/20160215-212056
base:   git://people.freedesktop.org/~airlied/linux.git drm-next
reproduce: make htmldocs

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'wedged'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'fmt'
   include/drm/drm_crtc.h:359: warning: No description found for parameter 'mode_blob'
   include/drm/drm_crtc.h:774: warning: No description found for parameter 'name'
>> include/drm/drm_crtc.h:1233: warning: No description found for parameter 'connector_id'
   include/drm/drm_crtc.h:1233: warning: No description found for parameter 'tile_blob_ptr'
   include/drm/drm_crtc.h:1272: warning: No description found for parameter 'rotation'
   include/drm/drm_crtc.h:1534: warning: No description found for parameter 'name'
   include/drm/drm_crtc.h:1534: warning: No description found for parameter 'mutex'
   include/drm/drm_crtc.h:1534: warning: No description found for parameter 'helper_private'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tile_idr'
>> include/drm/drm_crtc.h:2144: warning: No description found for parameter 'connector_ida'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'delayed_event'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'edid_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'dpms_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'path_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tile_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'plane_type_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'rotation_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_src_x'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_src_y'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_src_w'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_src_h'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_crtc_x'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_crtc_y'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_crtc_w'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_crtc_h'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_fb_id'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_crtc_id'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_active'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'prop_mode_id'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'dvi_i_subconnector_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'dvi_i_select_subconnector_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_subconnector_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_select_subconnector_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_mode_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_left_margin_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_right_margin_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_top_margin_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_bottom_margin_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_brightness_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_contrast_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_flicker_reduction_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_overscan_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_saturation_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'tv_hue_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'scaling_mode_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'aspect_ratio_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'dirty_info_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'suggested_x_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'suggested_y_property'
   include/drm/drm_crtc.h:2144: warning: No description found for parameter 'allow_fb_modifiers'
   include/drm/drm_dp_helper.h:749: warning: No description found for parameter 'i2c_nack_count'
   include/drm/drm_dp_helper.h:749: warning: No description found for parameter 'i2c_defer_count'
   drivers/gpu/drm/drm_dp_mst_topology.c:2364: warning: No description found for parameter 'connector'
   include/drm/drm_dp_mst_helper.h:92: warning: No description found for parameter 'cached_edid'
   include/drm/drm_dp_mst_helper.h:92: warning: No description found for parameter 'has_audio'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'max_dpcd_transaction_bytes'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'sink_count'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'total_slots'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'avail_slots'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'total_pbn'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'qlock'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'tx_msg_downq'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'tx_down_in_progress'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'payload_lock'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'proposed_vcpis'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'payloads'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'payload_mask'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'vcpi_mask'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'tx_waitq'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'work'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'tx_work'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'destroy_connector_list'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'destroy_connector_lock'
   include/drm/drm_dp_mst_helper.h:466: warning: No description found for parameter 'destroy_connector_work'
   drivers/gpu/drm/drm_dp_mst_topology.c:2364: warning: No description found for parameter 'connector'
   drivers/gpu/drm/drm_irq.c:176: warning: No description found for parameter 'flags'
   include/drm/drmP.h:168: warning: No description found for parameter 'fmt'
   include/drm/drmP.h:184: warning: No description found for parameter 'fmt'
   include/drm/drmP.h:202: warning: No description found for parameter 'fmt'
   include/drm/drmP.h:247: warning: No description found for parameter 'dev'
   include/drm/drmP.h:247: warning: No description found for parameter 'data'
   include/drm/drmP.h:247: warning: No description found for parameter 'file_priv'
   include/drm/drmP.h:280: warning: No description found for parameter 'ioctl'
   include/drm/drmP.h:280: warning: No description found for parameter '_func'
   include/drm/drmP.h:280: warning: No description found for parameter '_flags'
   include/drm/drmP.h:362: warning: cannot understand function prototype: 'struct drm_lock_data '
   include/drm/drmP.h:415: warning: cannot understand function prototype: 'struct drm_driver '
   include/drm/drmP.h:672: warning: cannot understand function prototype: 'struct drm_info_list '
   include/drm/drmP.h:682: warning: cannot understand function prototype: 'struct drm_info_node '
   include/drm/drmP.h:692: warning: cannot understand function prototype: 'struct drm_minor '
   include/drm/drmP.h:740: warning: cannot understand function prototype: 'struct drm_device '
   drivers/gpu/drm/i915/intel_runtime_pm.c:2173: warning: No description found for parameter 'resume'
   drivers/gpu/drm/i915/intel_runtime_pm.c:2173: warning: No description found for parameter 'resume'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'wedged'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'fmt'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'wedged'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'fmt'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'wedged'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'fmt'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'wedged'
   drivers/gpu/drm/i915/i915_irq.c:2659: warning: No description found for parameter 'fmt'
   drivers/gpu/drm/i915/i915_gem.c:421: warning: No description found for parameter 'dev'
   drivers/gpu/drm/i915/i915_gem.c:421: warning: No description found for parameter 'data'
   drivers/gpu/drm/i915/i915_gem.c:421: warning: No description found for parameter 'file'
   drivers/gpu/drm/i915/i915_gem.c:686: warning: No description found for parameter 'dev'
   drivers/gpu/drm/i915/i915_gem.c:686: warning: No description found for parameter 'data'
   drivers/gpu/drm/i915/i915_gem.c:686: warning: No description found for parameter 'file'
   drivers/gpu/drm/i915/i915_gem.c:767: warning: No description found for parameter 'dev'
   drivers/gpu/drm/i915/i915_gem.c:767: warning: No description found for parameter 'obj'
   drivers/gpu/drm/i915/i915_gem.c:767: warning: No description found for parameter 'args'

vim +/connector_id +1233 include/drm/drm_crtc.h

6ba2bd3d Todd Previte  2015-04-21  1217  	 * compliance testing - * Displayport Link CTS Core 1.2 rev1.1 4.2.2.6
6ba2bd3d Todd Previte  2015-04-21  1218  	 */
6ba2bd3d Todd Previte  2015-04-21  1219  	bool edid_corrupt;
6ba2bd3d Todd Previte  2015-04-21  1220  
30f65707 Thomas Wood   2014-06-18  1221  	struct dentry *debugfs_entry;
144ecb97 Daniel Vetter 2014-10-27  1222  
144ecb97 Daniel Vetter 2014-10-27  1223  	struct drm_connector_state *state;
40d9b043 Dave Airlie   2014-10-20  1224  
40d9b043 Dave Airlie   2014-10-20  1225  	/* DisplayID bits */
40d9b043 Dave Airlie   2014-10-20  1226  	bool has_tile;
40d9b043 Dave Airlie   2014-10-20  1227  	struct drm_tile_group *tile_group;
40d9b043 Dave Airlie   2014-10-20  1228  	bool tile_is_single_monitor;
40d9b043 Dave Airlie   2014-10-20  1229  
40d9b043 Dave Airlie   2014-10-20  1230  	uint8_t num_h_tile, num_v_tile;
40d9b043 Dave Airlie   2014-10-20  1231  	uint8_t tile_h_loc, tile_v_loc;
40d9b043 Dave Airlie   2014-10-20  1232  	uint16_t tile_h_size, tile_v_size;
f453ba04 Dave Airlie   2008-11-07 @1233  };
f453ba04 Dave Airlie   2008-11-07  1234  
f453ba04 Dave Airlie   2008-11-07  1235  /**
144ecb97 Daniel Vetter 2014-10-27  1236   * struct drm_plane_state - mutable plane state
07cc0ef6 Daniel Vetter 2014-11-27  1237   * @plane: backpointer to the plane
144ecb97 Daniel Vetter 2014-10-27  1238   * @crtc: currently bound CRTC, NULL if disabled
cc4ceb48 Daniel Vetter 2014-07-25  1239   * @fb: currently bound framebuffer
e2330f07 Daniel Vetter 2014-10-29  1240   * @fence: optional fence to wait for before scanning out @fb
144ecb97 Daniel Vetter 2014-10-27  1241   * @crtc_x: left position of visible portion of plane on crtc

:::::: The code at line 1233 was first introduced by commit
:::::: f453ba0460742ad027ae0c4c7d61e62817b3e7ef DRM: add mode setting support

:::::: TO: Dave Airlie <airlied@redhat.com>
:::::: CC: Dave Airlie <airlied@linux.ie>

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
Ville Syrjälä Feb. 16, 2016, 11:37 a.m. UTC | #2
On Mon, Feb 15, 2016 at 02:17:01PM +0100, Maarten Lankhorst wrote:
> Because we record connector_mask using 1 << drm_connector_index now
> the connector_mask should stay the same even when other connectors
> are removed. This was not the case with MST, in that case when removing
> a connector all other connectors may change their index.
> 
> This is fixed by waiting until the first get_connector_state to allocate
> connector_state, and force reallocation when state is too small.
> 
> As a side effect connector arrays no longer have to be preallocated,
> and can be allocated on first use which means a less allocations in
> the page flip only path.
> 
> Fixes: 14de6c44d149 ("drm/atomic: Remove drm_atomic_connectors_for_crtc.")
> Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
> ---
>  drivers/gpu/drm/drm_atomic.c        | 45 +++++++++++++++++--------------------
>  drivers/gpu/drm/drm_atomic_helper.c |  2 +-
>  drivers/gpu/drm/drm_crtc.c          | 45 +++++++++++++------------------------
>  include/drm/drm_crtc.h              |  8 ++++++-
>  4 files changed, 45 insertions(+), 55 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
> index 8fb469c4e4b8..5d4774450540 100644
> --- a/drivers/gpu/drm/drm_atomic.c
> +++ b/drivers/gpu/drm/drm_atomic.c
> @@ -65,8 +65,6 @@ drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
>  	 */
>  	state->allow_modeset = true;
>  
> -	state->num_connector = ACCESS_ONCE(dev->mode_config.num_connector);
> -
>  	state->crtcs = kcalloc(dev->mode_config.num_crtc,
>  			       sizeof(*state->crtcs), GFP_KERNEL);
>  	if (!state->crtcs)
> @@ -83,16 +81,6 @@ drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
>  				      sizeof(*state->plane_states), GFP_KERNEL);
>  	if (!state->plane_states)
>  		goto fail;
> -	state->connectors = kcalloc(state->num_connector,
> -				    sizeof(*state->connectors),
> -				    GFP_KERNEL);
> -	if (!state->connectors)
> -		goto fail;
> -	state->connector_states = kcalloc(state->num_connector,
> -					  sizeof(*state->connector_states),
> -					  GFP_KERNEL);
> -	if (!state->connector_states)
> -		goto fail;
>  
>  	state->dev = dev;
>  
> @@ -823,19 +811,28 @@ drm_atomic_get_connector_state(struct drm_atomic_state *state,
>  
>  	index = drm_connector_index(connector);
>  
> -	/*
> -	 * Construction of atomic state updates can race with a connector
> -	 * hot-add which might overflow. In this case flip the table and just
> -	 * restart the entire ioctl - no one is fast enough to livelock a cpu
> -	 * with physical hotplug events anyway.
> -	 *
> -	 * Note that we only grab the indexes once we have the right lock to
> -	 * prevent hotplug/unplugging of connectors. So removal is no problem,
> -	 * at most the array is a bit too large.
> -	 */
>  	if (index >= state->num_connector) {
> -		DRM_DEBUG_ATOMIC("Hot-added connector would overflow state array, restarting\n");
> -		return ERR_PTR(-EAGAIN);
> +		struct drm_connector **c;
> +		struct drm_connector_state **cs;
> +
> +		u32 alloc = max(index + 1, config->num_connector);

Why u32?

> +
> +		c = krealloc(state->connectors, alloc * sizeof(*state->connectors), GFP_KERNEL);
> +		if (!c)
> +			return ERR_PTR(-ENOMEM);
> +
> +		state->connectors = c;
> +		memset(&state->connectors[state->num_connector], 0,
> +		       sizeof(*state->connectors) * (alloc - state->num_connector));
> +
> +		cs = krealloc(state->connector_states, alloc * sizeof(*state->connector_states), GFP_KERNEL);
> +		if (!cs)
> +			return ERR_PTR(-ENOMEM);
> +
> +		state->connector_states = cs;
> +		memset(&state->connector_states[state->num_connector], 0,
> +		       sizeof(*state->connector_states) * (alloc - state->num_connector));
> +		state->num_connector = alloc;
>  	}
>  
>  	if (state->connector_states[index])
> diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
> index 2b430b05f35d..4da4f2a49078 100644
> --- a/drivers/gpu/drm/drm_atomic_helper.c
> +++ b/drivers/gpu/drm/drm_atomic_helper.c
> @@ -1535,7 +1535,7 @@ void drm_atomic_helper_swap_state(struct drm_device *dev,
>  {
>  	int i;
>  
> -	for (i = 0; i < dev->mode_config.num_connector; i++) {
> +	for (i = 0; i < state->num_connector; i++) {
>  		struct drm_connector *connector = state->connectors[i];
>  
>  		if (!connector)
> diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
> index 65258acddb90..ea00aea88de7 100644
> --- a/drivers/gpu/drm/drm_crtc.c
> +++ b/drivers/gpu/drm/drm_crtc.c
> @@ -918,12 +918,18 @@ int drm_connector_init(struct drm_device *dev,
>  	connector->base.properties = &connector->properties;
>  	connector->dev = dev;
>  	connector->funcs = funcs;

Could use an empty line here.

> +	connector->connector_id = ida_simple_get(&config->connector_ida, 0, 0, GFP_KERNEL);
> +	if (connector->connector_id < 0) {
> +		ret = connector->connector_id;
> +		goto out_put;
> +	}
> +
>  	connector->connector_type = connector_type;
>  	connector->connector_type_id =
>  		ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
>  	if (connector->connector_type_id < 0) {
>  		ret = connector->connector_type_id;
> -		goto out_put;
> +		goto out_put_id;
>  	}
>  	connector->name =
>  		kasprintf(GFP_KERNEL, "%s-%d",
> @@ -931,7 +937,7 @@ int drm_connector_init(struct drm_device *dev,
>  			  connector->connector_type_id);
>  	if (!connector->name) {
>  		ret = -ENOMEM;
> -		goto out_put;
> +		goto out_put_type_id;
>  	}
>  
>  	INIT_LIST_HEAD(&connector->probed_modes);
> @@ -959,7 +965,12 @@ int drm_connector_init(struct drm_device *dev,
>  	}
>  
>  	connector->debugfs_entry = NULL;
> -
> +out_put_type_id:
> +	if (ret)
> +		ida_remove(connector_ida, connector->connector_type_id);
> +out_put_id:
> +	if (ret)
> +		ida_remove(&config->connector_ida, connector->connector_id);


Should there be an ida_remove() call somewhere when
unregistering or destroying the connector?

BTW looking at intel_dp_destroy_mst_connector(), shouldn't we
unregister/do something before we do the modeset? What's there to
prevent userspac/someone from racing with this and re-enabling the
connector before we unregister it? Or maybe the connector is already
defunct by this time and something else will prevent any modeset
using the connector from succeeding?

>  out_put:
>  	if (ret)
>  		drm_mode_object_put(dev, &connector->base);
> @@ -1013,32 +1024,6 @@ void drm_connector_cleanup(struct drm_connector *connector)
>  EXPORT_SYMBOL(drm_connector_cleanup);
>  
>  /**
> - * drm_connector_index - find the index of a registered connector
> - * @connector: connector to find index for
> - *
> - * Given a registered connector, return the index of that connector within a DRM
> - * device's list of connectors.
> - */
> -unsigned int drm_connector_index(struct drm_connector *connector)
> -{
> -	unsigned int index = 0;
> -	struct drm_connector *tmp;
> -	struct drm_mode_config *config = &connector->dev->mode_config;
> -
> -	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
> -
> -	drm_for_each_connector(tmp, connector->dev) {
> -		if (tmp == connector)
> -			return index;
> -
> -		index++;
> -	}
> -
> -	BUG();
> -}
> -EXPORT_SYMBOL(drm_connector_index);
> -
> -/**
>   * drm_connector_register - register a connector
>   * @connector: the connector to register
>   *
> @@ -5838,6 +5823,7 @@ void drm_mode_config_init(struct drm_device *dev)
>  	INIT_LIST_HEAD(&dev->mode_config.plane_list);
>  	idr_init(&dev->mode_config.crtc_idr);
>  	idr_init(&dev->mode_config.tile_idr);
> +	ida_init(&dev->mode_config.connector_ida);
>  
>  	drm_modeset_lock_all(dev);
>  	drm_mode_create_standard_properties(dev);
> @@ -5918,6 +5904,7 @@ void drm_mode_config_cleanup(struct drm_device *dev)
>  		crtc->funcs->destroy(crtc);
>  	}
>  
> +	ida_destroy(&dev->mode_config.connector_ida);
>  	idr_destroy(&dev->mode_config.tile_idr);
>  	idr_destroy(&dev->mode_config.crtc_idr);
>  	drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
> diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
> index 8c7fb3d0f9d0..7fad193dc645 100644
> --- a/include/drm/drm_crtc.h
> +++ b/include/drm/drm_crtc.h
> @@ -1168,6 +1168,7 @@ struct drm_connector {
>  	struct drm_mode_object base;
>  
>  	char *name;
> +	int connector_id;
>  	int connector_type;
>  	int connector_type_id;
>  	bool interlace_allowed;
> @@ -2049,6 +2050,7 @@ struct drm_mode_config {
>  	struct list_head fb_list;
>  
>  	int num_connector;
> +	struct ida connector_ida;
>  	struct list_head connector_list;
>  	int num_encoder;
>  	struct list_head encoder_list;
> @@ -2213,7 +2215,11 @@ int drm_connector_register(struct drm_connector *connector);
>  void drm_connector_unregister(struct drm_connector *connector);
>  
>  extern void drm_connector_cleanup(struct drm_connector *connector);
> -extern unsigned int drm_connector_index(struct drm_connector *connector);
> +static inline unsigned drm_connector_index(struct drm_connector *connector)
> +{
> +	return connector->connector_id;
> +}
> +
>  /* helper to unplug all connectors from sysfs for device */
>  extern void drm_connector_unplug_all(struct drm_device *dev);
>  
> -- 
> 2.1.0
> 
> _______________________________________________
> dri-devel mailing list
> dri-devel@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/dri-devel
Dave Airlie Feb. 19, 2016, 3:21 a.m. UTC | #3
On 16 February 2016 at 21:37, Ville Syrjälä
<ville.syrjala@linux.intel.com> wrote:
> On Mon, Feb 15, 2016 at 02:17:01PM +0100, Maarten Lankhorst wrote:
>> Because we record connector_mask using 1 << drm_connector_index now
>> the connector_mask should stay the same even when other connectors
>> are removed. This was not the case with MST, in that case when removing
>> a connector all other connectors may change their index.
>>
>> This is fixed by waiting until the first get_connector_state to allocate
>> connector_state, and force reallocation when state is too small.
>>
>> As a side effect connector arrays no longer have to be preallocated,
>> and can be allocated on first use which means a less allocations in
>> the page flip only path.

Daniel you said something on irc about v2 of this for -fixes? Did I miss v2?

Dave.
Maarten Lankhorst Feb. 22, 2016, 9:34 a.m. UTC | #4
Op 19-02-16 om 04:21 schreef Dave Airlie:
> On 16 February 2016 at 21:37, Ville Syrjälä
> <ville.syrjala@linux.intel.com> wrote:
>> On Mon, Feb 15, 2016 at 02:17:01PM +0100, Maarten Lankhorst wrote:
>>> Because we record connector_mask using 1 << drm_connector_index now
>>> the connector_mask should stay the same even when other connectors
>>> are removed. This was not the case with MST, in that case when removing
>>> a connector all other connectors may change their index.
>>>
>>> This is fixed by waiting until the first get_connector_state to allocate
>>> connector_state, and force reallocation when state is too small.
>>>
>>> As a side effect connector arrays no longer have to be preallocated,
>>> and can be allocated on first use which means a less allocations in
>>> the page flip only path.
> Daniel you said something on irc about v2 of this for -fixes? Did I miss v2?
>
> Dave.
"[PATCH v2] drm/atomic: Allow for holes in connector state, v2."

It wasn't sent in this thread to give CI a chance to run.
diff mbox

Patch

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 8fb469c4e4b8..5d4774450540 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -65,8 +65,6 @@  drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
 	 */
 	state->allow_modeset = true;
 
-	state->num_connector = ACCESS_ONCE(dev->mode_config.num_connector);
-
 	state->crtcs = kcalloc(dev->mode_config.num_crtc,
 			       sizeof(*state->crtcs), GFP_KERNEL);
 	if (!state->crtcs)
@@ -83,16 +81,6 @@  drm_atomic_state_init(struct drm_device *dev, struct drm_atomic_state *state)
 				      sizeof(*state->plane_states), GFP_KERNEL);
 	if (!state->plane_states)
 		goto fail;
-	state->connectors = kcalloc(state->num_connector,
-				    sizeof(*state->connectors),
-				    GFP_KERNEL);
-	if (!state->connectors)
-		goto fail;
-	state->connector_states = kcalloc(state->num_connector,
-					  sizeof(*state->connector_states),
-					  GFP_KERNEL);
-	if (!state->connector_states)
-		goto fail;
 
 	state->dev = dev;
 
@@ -823,19 +811,28 @@  drm_atomic_get_connector_state(struct drm_atomic_state *state,
 
 	index = drm_connector_index(connector);
 
-	/*
-	 * Construction of atomic state updates can race with a connector
-	 * hot-add which might overflow. In this case flip the table and just
-	 * restart the entire ioctl - no one is fast enough to livelock a cpu
-	 * with physical hotplug events anyway.
-	 *
-	 * Note that we only grab the indexes once we have the right lock to
-	 * prevent hotplug/unplugging of connectors. So removal is no problem,
-	 * at most the array is a bit too large.
-	 */
 	if (index >= state->num_connector) {
-		DRM_DEBUG_ATOMIC("Hot-added connector would overflow state array, restarting\n");
-		return ERR_PTR(-EAGAIN);
+		struct drm_connector **c;
+		struct drm_connector_state **cs;
+
+		u32 alloc = max(index + 1, config->num_connector);
+
+		c = krealloc(state->connectors, alloc * sizeof(*state->connectors), GFP_KERNEL);
+		if (!c)
+			return ERR_PTR(-ENOMEM);
+
+		state->connectors = c;
+		memset(&state->connectors[state->num_connector], 0,
+		       sizeof(*state->connectors) * (alloc - state->num_connector));
+
+		cs = krealloc(state->connector_states, alloc * sizeof(*state->connector_states), GFP_KERNEL);
+		if (!cs)
+			return ERR_PTR(-ENOMEM);
+
+		state->connector_states = cs;
+		memset(&state->connector_states[state->num_connector], 0,
+		       sizeof(*state->connector_states) * (alloc - state->num_connector));
+		state->num_connector = alloc;
 	}
 
 	if (state->connector_states[index])
diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 2b430b05f35d..4da4f2a49078 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -1535,7 +1535,7 @@  void drm_atomic_helper_swap_state(struct drm_device *dev,
 {
 	int i;
 
-	for (i = 0; i < dev->mode_config.num_connector; i++) {
+	for (i = 0; i < state->num_connector; i++) {
 		struct drm_connector *connector = state->connectors[i];
 
 		if (!connector)
diff --git a/drivers/gpu/drm/drm_crtc.c b/drivers/gpu/drm/drm_crtc.c
index 65258acddb90..ea00aea88de7 100644
--- a/drivers/gpu/drm/drm_crtc.c
+++ b/drivers/gpu/drm/drm_crtc.c
@@ -918,12 +918,18 @@  int drm_connector_init(struct drm_device *dev,
 	connector->base.properties = &connector->properties;
 	connector->dev = dev;
 	connector->funcs = funcs;
+	connector->connector_id = ida_simple_get(&config->connector_ida, 0, 0, GFP_KERNEL);
+	if (connector->connector_id < 0) {
+		ret = connector->connector_id;
+		goto out_put;
+	}
+
 	connector->connector_type = connector_type;
 	connector->connector_type_id =
 		ida_simple_get(connector_ida, 1, 0, GFP_KERNEL);
 	if (connector->connector_type_id < 0) {
 		ret = connector->connector_type_id;
-		goto out_put;
+		goto out_put_id;
 	}
 	connector->name =
 		kasprintf(GFP_KERNEL, "%s-%d",
@@ -931,7 +937,7 @@  int drm_connector_init(struct drm_device *dev,
 			  connector->connector_type_id);
 	if (!connector->name) {
 		ret = -ENOMEM;
-		goto out_put;
+		goto out_put_type_id;
 	}
 
 	INIT_LIST_HEAD(&connector->probed_modes);
@@ -959,7 +965,12 @@  int drm_connector_init(struct drm_device *dev,
 	}
 
 	connector->debugfs_entry = NULL;
-
+out_put_type_id:
+	if (ret)
+		ida_remove(connector_ida, connector->connector_type_id);
+out_put_id:
+	if (ret)
+		ida_remove(&config->connector_ida, connector->connector_id);
 out_put:
 	if (ret)
 		drm_mode_object_put(dev, &connector->base);
@@ -1013,32 +1024,6 @@  void drm_connector_cleanup(struct drm_connector *connector)
 EXPORT_SYMBOL(drm_connector_cleanup);
 
 /**
- * drm_connector_index - find the index of a registered connector
- * @connector: connector to find index for
- *
- * Given a registered connector, return the index of that connector within a DRM
- * device's list of connectors.
- */
-unsigned int drm_connector_index(struct drm_connector *connector)
-{
-	unsigned int index = 0;
-	struct drm_connector *tmp;
-	struct drm_mode_config *config = &connector->dev->mode_config;
-
-	WARN_ON(!drm_modeset_is_locked(&config->connection_mutex));
-
-	drm_for_each_connector(tmp, connector->dev) {
-		if (tmp == connector)
-			return index;
-
-		index++;
-	}
-
-	BUG();
-}
-EXPORT_SYMBOL(drm_connector_index);
-
-/**
  * drm_connector_register - register a connector
  * @connector: the connector to register
  *
@@ -5838,6 +5823,7 @@  void drm_mode_config_init(struct drm_device *dev)
 	INIT_LIST_HEAD(&dev->mode_config.plane_list);
 	idr_init(&dev->mode_config.crtc_idr);
 	idr_init(&dev->mode_config.tile_idr);
+	ida_init(&dev->mode_config.connector_ida);
 
 	drm_modeset_lock_all(dev);
 	drm_mode_create_standard_properties(dev);
@@ -5918,6 +5904,7 @@  void drm_mode_config_cleanup(struct drm_device *dev)
 		crtc->funcs->destroy(crtc);
 	}
 
+	ida_destroy(&dev->mode_config.connector_ida);
 	idr_destroy(&dev->mode_config.tile_idr);
 	idr_destroy(&dev->mode_config.crtc_idr);
 	drm_modeset_lock_fini(&dev->mode_config.connection_mutex);
diff --git a/include/drm/drm_crtc.h b/include/drm/drm_crtc.h
index 8c7fb3d0f9d0..7fad193dc645 100644
--- a/include/drm/drm_crtc.h
+++ b/include/drm/drm_crtc.h
@@ -1168,6 +1168,7 @@  struct drm_connector {
 	struct drm_mode_object base;
 
 	char *name;
+	int connector_id;
 	int connector_type;
 	int connector_type_id;
 	bool interlace_allowed;
@@ -2049,6 +2050,7 @@  struct drm_mode_config {
 	struct list_head fb_list;
 
 	int num_connector;
+	struct ida connector_ida;
 	struct list_head connector_list;
 	int num_encoder;
 	struct list_head encoder_list;
@@ -2213,7 +2215,11 @@  int drm_connector_register(struct drm_connector *connector);
 void drm_connector_unregister(struct drm_connector *connector);
 
 extern void drm_connector_cleanup(struct drm_connector *connector);
-extern unsigned int drm_connector_index(struct drm_connector *connector);
+static inline unsigned drm_connector_index(struct drm_connector *connector)
+{
+	return connector->connector_id;
+}
+
 /* helper to unplug all connectors from sysfs for device */
 extern void drm_connector_unplug_all(struct drm_device *dev);