Re: [PATCH v3 13/13] coresight: Fix CTI module refcount leak by making it a helper device
From: James Clark
Date: Tue Apr 04 2023 - 09:04:51 EST
On 04/04/2023 13:55, James Clark wrote:
>
>
> On 04/04/2023 10:21, Suzuki K Poulose wrote:
>> On 29/03/2023 12:53, James Clark wrote:
>>> The CTI module has some hard coded refcounting code that has a leak.
>>> For example running perf and then trying to unload it fails:
>>>
>>> perf record -e cs_etm// -a -- ls
>>> rmmod coresight_cti
>>>
>>> rmmod: ERROR: Module coresight_cti is in use
>>>
>>> The coresight core already handles references of devices in use, so by
>>> making CTI a normal helper device, we get working refcounting for free.
>>>
>>> Signed-off-by: James Clark <james.clark@xxxxxxx>
>>> ---
>>> drivers/hwtracing/coresight/coresight-core.c | 99 ++++++-------------
>>> .../hwtracing/coresight/coresight-cti-core.c | 52 +++++-----
>>> .../hwtracing/coresight/coresight-cti-sysfs.c | 4 +-
>>> drivers/hwtracing/coresight/coresight-cti.h | 4 +-
>>> drivers/hwtracing/coresight/coresight-priv.h | 4 +-
>>> drivers/hwtracing/coresight/coresight-sysfs.c | 4 +
>>> include/linux/coresight.h | 30 +-----
>>> 7 files changed, 70 insertions(+), 127 deletions(-)
>>>
>>> diff --git a/drivers/hwtracing/coresight/coresight-core.c
>>> b/drivers/hwtracing/coresight/coresight-core.c
>>> index 65f5bd8516d8..458d91b4e23f 100644
>>> --- a/drivers/hwtracing/coresight/coresight-core.c
>>> +++ b/drivers/hwtracing/coresight/coresight-core.c
>>> @@ -254,60 +254,39 @@ void coresight_disclaim_device(struct
>>> coresight_device *csdev)
>>> }
>>> EXPORT_SYMBOL_GPL(coresight_disclaim_device);
>>> -/* enable or disable an associated CTI device of the supplied CS
>>> device */
>>> -static int
>>> -coresight_control_assoc_ectdev(struct coresight_device *csdev, bool
>>> enable)
>>> -{
>>> - int ect_ret = 0;
>>> - struct coresight_device *ect_csdev = csdev->ect_dev;
>>> - struct module *mod;
>>> -
>>> - if (!ect_csdev)
>>> - return 0;
>>> - if ((!ect_ops(ect_csdev)->enable) || (!ect_ops(ect_csdev)->disable))
>>> - return 0;
>>> -
>>> - mod = ect_csdev->dev.parent->driver->owner;
>>> - if (enable) {
>>> - if (try_module_get(mod)) {
>>> - ect_ret = ect_ops(ect_csdev)->enable(ect_csdev);
>>> - if (ect_ret) {
>>> - module_put(mod);
>>> - } else {
>>> - get_device(ect_csdev->dev.parent);
>>> - csdev->ect_enabled = true;
>>> - }
>>> - } else
>>> - ect_ret = -ENODEV;
>>> - } else {
>>> - if (csdev->ect_enabled) {
>>> - ect_ret = ect_ops(ect_csdev)->disable(ect_csdev);
>>> - put_device(ect_csdev->dev.parent);
>>> - module_put(mod);
>>> - csdev->ect_enabled = false;
>>> - }
>>> - }
>>> -
>>> - /* output warning if ECT enable is preventing trace operation */
>>> - if (ect_ret)
>>> - dev_info(&csdev->dev, "Associated ECT device (%s) %s failed\n",
>>> - dev_name(&ect_csdev->dev),
>>> - enable ? "enable" : "disable");
>>> - return ect_ret;
>>> -}
>>> -
>>> /*
>>> - * Set the associated ect / cti device while holding the coresight_mutex
>>> + * Add a helper as an output device while holding the coresight_mutex
>>> * to avoid a race with coresight_enable that may try to use this
>>> value.
>>> */
>>> -void coresight_set_assoc_ectdev_mutex(struct coresight_device *csdev,
>>> - struct coresight_device *ect_csdev)
>>> +void coresight_add_helper_mutex(struct coresight_device *csdev,
>>> + struct coresight_device *helper)
>>
>> minor nit: It may be a good idea to rename this, in line with the
>> kernel naming convention :
>>
>> coresight_add_helper_unlocked()
>>
>> Or if this is the only variant, it is OK to leave it as :
>> coresight_add_helper()
>> with a big fat comment in the function description to indicate
>> that it takes the mutex and may be even add a :
>>
> There is already a bit of a comment in the description but I can expand
> on it more.
>
>> might_sleep() and lockdep_assert_not_held(&coresight_mutex);
>>
>> in the function.
>>
>
> I'm not sure if lockdep_assert_not_held() would be right because
> sometimes it could be held if another device is being created at the
> same time? Or something like a session is started at the same time a CTI
> device is added.
>
Oh I see it's not for any task, it's just for the current one. That
makes sense then I can add it.
Although it looks like it only warns when lockdep is enabled, but don't
you get a warning anyway if you try to take the lock twice with lockdep
enabled? So I'm not sure why we would add lockdep_assert_not_held() here
and not on all the mutex_lock() calls?
>>> {
>>> + int i;
>>> + struct coresight_connection conn = {};
>>> +
>>> mutex_lock(&coresight_mutex);
>>> - csdev->ect_dev = ect_csdev;
>>> + conn.dest_fwnode = fwnode_handle_get(dev_fwnode(&helper->dev));
>>> + conn.dest_dev = helper;
>>> + conn.dest_port = conn.src_port = -1;
>>> + conn.src_dev = csdev;
>>> +
>>> + /*
>>> + * Check for duplicates because this is called every time a helper
>>> + * device is re-loaded. Existing connections will get re-linked
>>> + * automatically.
>>> + */
>>
>> Thanks for adding this comment here. It does look like the already added
>> output connection to the "origin" device would automatically resolve the
>> connection and add in the "in-connection" to the CTI device.
>>
>>> + for (i = 0; i < csdev->pdata->nr_outconns; ++i)
>>> + if (csdev->pdata->out_conns[i]->dest_fwnode == conn.dest_fwnode)
>>> + goto unlock;
>>> +
>>> + coresight_add_out_conn(csdev->dev.parent, csdev->pdata, &conn);
>>
>> This makes me wonder if we should return the new connection in
>> coresight_add_out_conn() in case of success, rather than assuming the
>> last one (which is always the case though.).
>>
>> i.e.,
>> new_conn = coresight_add_out_conn(...)
>> if (new_conn)
>> coresight_add_in_conn(new_conn);
>>
>
> Yeah I thought about doing that too, will change it.
>
>>> + coresight_add_in_conn(
>>> + csdev->pdata->out_conns[csdev->pdata->nr_outconns - 1]);
>>> +
>>> +unlock:
>>> mutex_unlock(&coresight_mutex);
>>> }
>>> -EXPORT_SYMBOL_GPL(coresight_set_assoc_ectdev_mutex);
>>> +EXPORT_SYMBOL_GPL(coresight_add_helper_mutex);
>>> static int coresight_enable_sink(struct coresight_device *csdev,
>>> enum cs_mode mode, void *data)
>>> @@ -321,12 +300,8 @@ static int coresight_enable_sink(struct
>>> coresight_device *csdev,
>>> if (!sink_ops(csdev)->enable)
>>> return -EINVAL;
>>> - ret = coresight_control_assoc_ectdev(csdev, true);
>>> - if (ret)
>>> - return ret;
>>> ret = sink_ops(csdev)->enable(csdev, mode, data);
>>> if (ret) {
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> return ret;
>>> }
>>> csdev->enable = true;
>>> @@ -344,7 +319,6 @@ static void coresight_disable_sink(struct
>>> coresight_device *csdev)
>>> ret = sink_ops(csdev)->disable(csdev);
>>> if (ret)
>>> return;
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> csdev->enable = false;
>>> }
>>> @@ -369,17 +343,11 @@ static int coresight_enable_link(struct
>>> coresight_device *csdev,
>>> return PTR_ERR(outconn);
>>> if (link_ops(csdev)->enable) {
>>> - ret = coresight_control_assoc_ectdev(csdev, true);
>>> - if (!ret) {
>>> - ret = link_ops(csdev)->enable(csdev, inconn, outconn);
>>> - if (ret)
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> - }
>>> + ret = link_ops(csdev)->enable(csdev, inconn, outconn);
>>> + if (!ret)
>>> + csdev->enable = true;
>>> }
>>> - if (!ret)
>>> - csdev->enable = true;
>>> -
>>> return ret;
>>> }
>>> @@ -400,7 +368,6 @@ static void coresight_disable_link(struct
>>> coresight_device *csdev,
>>> if (link_ops(csdev)->disable) {
>>> link_ops(csdev)->disable(csdev, inconn, outconn);
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> }
>>> if (link_subtype == CORESIGHT_DEV_SUBTYPE_LINK_MERG) {
>>> @@ -428,14 +395,9 @@ int coresight_enable_source(struct
>>> coresight_device *csdev, void *data,
>>> if (!csdev->enable) {
>>> if (source_ops(csdev)->enable) {
>>> - ret = coresight_control_assoc_ectdev(csdev, true);
>>> - if (ret)
>>> - return ret;
>>> ret = source_ops(csdev)->enable(csdev, data, mode);
>>> - if (ret) {
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> + if (ret)
>>> return ret;
>>> - }
>>> }
>>> csdev->enable = true;
>>> }
>>> @@ -499,7 +461,6 @@ bool coresight_disable_source(struct
>>> coresight_device *csdev, void *data)
>>> if (atomic_dec_return(&csdev->refcnt) == 0) {
>>> if (source_ops(csdev)->disable)
>>> source_ops(csdev)->disable(csdev, data);
>>> - coresight_control_assoc_ectdev(csdev, false);
>>> coresight_disable_helpers(csdev);
>>> csdev->enable = false;
>>> }
>>> diff --git a/drivers/hwtracing/coresight/coresight-cti-core.c
>>> b/drivers/hwtracing/coresight/coresight-cti-core.c
>>> index 277c890a1f1f..db7a2212ec18 100644
>>> --- a/drivers/hwtracing/coresight/coresight-cti-core.c
>>> +++ b/drivers/hwtracing/coresight/coresight-cti-core.c
>>> @@ -555,7 +555,10 @@ static void cti_add_assoc_to_csdev(struct
>>> coresight_device *csdev)
>>> mutex_lock(&ect_mutex);
>>> /* exit if current is an ECT device.*/
>>> - if ((csdev->type == CORESIGHT_DEV_TYPE_ECT) || list_empty(&ect_net))
>>> + if ((csdev->type == CORESIGHT_DEV_TYPE_HELPER &&
>>> + csdev->subtype.helper_subtype ==
>>> + CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI) ||
>>> + list_empty(&ect_net))
>>> goto cti_add_done;
>>> /* if we didn't find the csdev previously we used the fwnode
>>> name */
>>> @@ -571,8 +574,7 @@ static void cti_add_assoc_to_csdev(struct
>>> coresight_device *csdev)
>>> * if we found a matching csdev then update the ECT
>>> * association pointer for the device with this CTI.
>>> */
>>> - coresight_set_assoc_ectdev_mutex(csdev,
>>> - ect_item->csdev);
>>> + coresight_add_helper_mutex(csdev, ect_item->csdev);
>>> break;
>>> }
>>> }
>>> @@ -582,26 +584,30 @@ static void cti_add_assoc_to_csdev(struct
>>> coresight_device *csdev)
>>> /*
>>> * Removing the associated devices is easier.
>>> - * A CTI will not have a value for csdev->ect_dev.
>>> */
>>> static void cti_remove_assoc_from_csdev(struct coresight_device *csdev)
>>> {
>>> struct cti_drvdata *ctidrv;
>>> struct cti_trig_con *tc;
>>> + union coresight_dev_subtype cti_subtype = {
>>> + .helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI
>>> + };
>>> + struct coresight_device *cti_csdev = coresight_find_output_type(
>>> + csdev->pdata, CORESIGHT_DEV_TYPE_HELPER, cti_subtype);
>>
>> minor nit: Please could we split the initialisation ? Or at least move
>> this after the next variable declaration below ?
>>
>>
>> Rest looks fine to me.
>>
>> Suzuki
>>
>>> struct cti_device *ctidev;
>>> + if (!cti_csdev)
>>> + return;
>>> +
>>> mutex_lock(&ect_mutex);
>>> - if (csdev->ect_dev) {
>>> - ctidrv = csdev_to_cti_drvdata(csdev->ect_dev);
>>> - ctidev = &ctidrv->ctidev;
>>> - list_for_each_entry(tc, &ctidev->trig_cons, node) {
>>> - if (tc->con_dev == csdev) {
>>> - cti_remove_sysfs_link(ctidrv, tc);
>>> - tc->con_dev = NULL;
>>> - break;
>>> - }
>>> + ctidrv = csdev_to_cti_drvdata(cti_csdev);
>>> + ctidev = &ctidrv->ctidev;
>>> + list_for_each_entry(tc, &ctidev->trig_cons, node) {
>>> + if (tc->con_dev == csdev) {
>>> + cti_remove_sysfs_link(ctidrv, tc);
>>> + tc->con_dev = NULL;
>>> + break;
>>> }
>>> - csdev->ect_dev = NULL;
>>> }
>>> mutex_unlock(&ect_mutex);
>>> }
>>> @@ -630,8 +636,8 @@ static void cti_update_conn_xrefs(struct
>>> cti_drvdata *drvdata)
>>> /* if we can set the sysfs link */
>>> if (cti_add_sysfs_link(drvdata, tc))
>>> /* set the CTI/csdev association */
>>> - coresight_set_assoc_ectdev_mutex(tc->con_dev,
>>> - drvdata->csdev);
>>> + coresight_add_helper_mutex(tc->con_dev,
>>> + drvdata->csdev);
>>> else
>>> /* otherwise remove reference from CTI */
>>> tc->con_dev = NULL;
>>> @@ -646,8 +652,6 @@ static void cti_remove_conn_xrefs(struct
>>> cti_drvdata *drvdata)
>>> list_for_each_entry(tc, &ctidev->trig_cons, node) {
>>> if (tc->con_dev) {
>>> - coresight_set_assoc_ectdev_mutex(tc->con_dev,
>>> - NULL);
>>> cti_remove_sysfs_link(drvdata, tc);
>>> tc->con_dev = NULL;
>>> }
>>> @@ -795,27 +799,27 @@ static void cti_pm_release(struct cti_drvdata
>>> *drvdata)
>>> }
>>> /** cti ect operations **/
>>> -int cti_enable(struct coresight_device *csdev)
>>> +int cti_enable(struct coresight_device *csdev, enum cs_mode mode,
>>> void *data)
>>> {
>>> struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
>>> return cti_enable_hw(drvdata);
>>> }
>>> -int cti_disable(struct coresight_device *csdev)
>>> +int cti_disable(struct coresight_device *csdev, void *data)
>>> {
>>> struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev);
>>> return cti_disable_hw(drvdata);
>>> }
>>> -static const struct coresight_ops_ect cti_ops_ect = {
>>> +static const struct coresight_ops_helper cti_ops_ect = {
>>> .enable = cti_enable,
>>> .disable = cti_disable,
>>> };
>>> static const struct coresight_ops cti_ops = {
>>> - .ect_ops = &cti_ops_ect,
>>> + .helper_ops = &cti_ops_ect,
>>> };
>>> /*
>>> @@ -922,8 +926,8 @@ static int cti_probe(struct amba_device *adev,
>>> const struct amba_id *id)
>>> /* set up coresight component description */
>>> cti_desc.pdata = pdata;
>>> - cti_desc.type = CORESIGHT_DEV_TYPE_ECT;
>>> - cti_desc.subtype.ect_subtype = CORESIGHT_DEV_SUBTYPE_ECT_CTI;
>>> + cti_desc.type = CORESIGHT_DEV_TYPE_HELPER;
>>> + cti_desc.subtype.helper_subtype =
>>> CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI;
>>> cti_desc.ops = &cti_ops;
>>> cti_desc.groups = drvdata->ctidev.con_groups;
>>> cti_desc.dev = dev;
>>> diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> index e528cff9d4e2..d25dd2737b49 100644
>>> --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c
>>> @@ -112,11 +112,11 @@ static ssize_t enable_store(struct device *dev,
>>> ret = pm_runtime_resume_and_get(dev->parent);
>>> if (ret)
>>> return ret;
>>> - ret = cti_enable(drvdata->csdev);
>>> + ret = cti_enable(drvdata->csdev, CS_MODE_SYSFS, NULL);
>>> if (ret)
>>> pm_runtime_put(dev->parent);
>>> } else {
>>> - ret = cti_disable(drvdata->csdev);
>>> + ret = cti_disable(drvdata->csdev, NULL);
>>> if (!ret)
>>> pm_runtime_put(dev->parent);
>>> }
>>> diff --git a/drivers/hwtracing/coresight/coresight-cti.h
>>> b/drivers/hwtracing/coresight/coresight-cti.h
>>> index 8b106b13a244..cb9ee616d01f 100644
>>> --- a/drivers/hwtracing/coresight/coresight-cti.h
>>> +++ b/drivers/hwtracing/coresight/coresight-cti.h
>>> @@ -215,8 +215,8 @@ int cti_add_connection_entry(struct device *dev,
>>> struct cti_drvdata *drvdata,
>>> const char *assoc_dev_name);
>>> struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int
>>> in_sigs,
>>> int out_sigs);
>>> -int cti_enable(struct coresight_device *csdev);
>>> -int cti_disable(struct coresight_device *csdev);
>>> +int cti_enable(struct coresight_device *csdev, enum cs_mode mode,
>>> void *data);
>>> +int cti_disable(struct coresight_device *csdev, void *data);
>>> void cti_write_all_hw_regs(struct cti_drvdata *drvdata);
>>> void cti_write_intack(struct device *dev, u32 ackval);
>>> void cti_write_single_reg(struct cti_drvdata *drvdata, int offset,
>>> u32 value);
>>> diff --git a/drivers/hwtracing/coresight/coresight-priv.h
>>> b/drivers/hwtracing/coresight/coresight-priv.h
>>> index a843f9d5c737..fff565d1cb42 100644
>>> --- a/drivers/hwtracing/coresight/coresight-priv.h
>>> +++ b/drivers/hwtracing/coresight/coresight-priv.h
>>> @@ -211,8 +211,8 @@ void coresight_release_platform_data(struct
>>> coresight_device *csdev,
>>> struct coresight_platform_data *pdata);
>>> struct coresight_device *
>>> coresight_find_csdev_by_fwnode(struct fwnode_handle *r_fwnode);
>>> -void coresight_set_assoc_ectdev_mutex(struct coresight_device *csdev,
>>> - struct coresight_device *ect_csdev);
>>> +void coresight_add_helper_mutex(struct coresight_device *csdev,
>>> + struct coresight_device *helper);
>>> void coresight_set_percpu_sink(int cpu, struct coresight_device
>>> *csdev);
>>> struct coresight_device *coresight_get_percpu_sink(int cpu);
>>> diff --git a/drivers/hwtracing/coresight/coresight-sysfs.c
>>> b/drivers/hwtracing/coresight/coresight-sysfs.c
>>> index 464ba5e1343b..dd78e9fcfc4d 100644
>>> --- a/drivers/hwtracing/coresight/coresight-sysfs.c
>>> +++ b/drivers/hwtracing/coresight/coresight-sysfs.c
>>> @@ -148,6 +148,10 @@ int coresight_make_links(struct coresight_device
>>> *orig,
>>> char *outs = NULL, *ins = NULL;
>>> struct coresight_sysfs_link *link = NULL;
>>> + /* Helper devices aren't shown in sysfs */
>>> + if (conn->dest_port == -1 && conn->src_port == -1)
>>> + return 0;
>>> +
>>> do {
>>> outs = devm_kasprintf(&orig->dev, GFP_KERNEL,
>>> "out:%d", conn->src_port);
>>> diff --git a/include/linux/coresight.h b/include/linux/coresight.h
>>> index d2739a0286f1..ed37552761e4 100644
>>> --- a/include/linux/coresight.h
>>> +++ b/include/linux/coresight.h
>>> @@ -40,8 +40,7 @@ enum coresight_dev_type {
>>> CORESIGHT_DEV_TYPE_LINK,
>>> CORESIGHT_DEV_TYPE_LINKSINK,
>>> CORESIGHT_DEV_TYPE_SOURCE,
>>> - CORESIGHT_DEV_TYPE_HELPER,
>>> - CORESIGHT_DEV_TYPE_ECT,
>>> + CORESIGHT_DEV_TYPE_HELPER
>>> };
>>> enum coresight_dev_subtype_sink {
>>> @@ -66,12 +65,7 @@ enum coresight_dev_subtype_source {
>>> enum coresight_dev_subtype_helper {
>>> CORESIGHT_DEV_SUBTYPE_HELPER_CATU,
>>> -};
>>> -
>>> -/* Embedded Cross Trigger (ECT) sub-types */
>>> -enum coresight_dev_subtype_ect {
>>> - CORESIGHT_DEV_SUBTYPE_ECT_NONE,
>>> - CORESIGHT_DEV_SUBTYPE_ECT_CTI,
>>> + CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI
>>> };
>>> /**
>>> @@ -84,8 +78,6 @@ enum coresight_dev_subtype_ect {
>>> * by @coresight_dev_subtype_source.
>>> * @helper_subtype: type of helper this component is, as defined
>>> * by @coresight_dev_subtype_helper.
>>> - * @ect_subtype: type of cross trigger this component is, as
>>> - * defined by @coresight_dev_subtype_ect
>>> */
>>> union coresight_dev_subtype {
>>> /* We have some devices which acts as LINK and SINK */
>>> @@ -95,7 +87,6 @@ union coresight_dev_subtype {
>>> };
>>> enum coresight_dev_subtype_source source_subtype;
>>> enum coresight_dev_subtype_helper helper_subtype;
>>> - enum coresight_dev_subtype_ect ect_subtype;
>>> };
>>> /**
>>> @@ -237,8 +228,6 @@ struct coresight_sysfs_link {
>>> * from source to that sink.
>>> * @ea: Device attribute for sink representation under PMU
>>> directory.
>>> * @def_sink: cached reference to default sink found for this
>>> device.
>>> - * @ect_dev: Associated cross trigger device. Not part of the
>>> trace data
>>> - * path or connections.
>>> * @nr_links: number of sysfs links created to other components
>>> from this
>>> * device. These will appear in the "connections" group.
>>> * @has_conns_grp: Have added a "connections" group for sysfs links.
>>> @@ -261,12 +250,9 @@ struct coresight_device {
>>> bool activated; /* true only if a sink is part of a path */
>>> struct dev_ext_attribute *ea;
>>> struct coresight_device *def_sink;
>>> - /* cross trigger handling */
>>> - struct coresight_device *ect_dev;
>>> /* sysfs links between components */
>>> int nr_links;
>>> bool has_conns_grp;
>>> - bool ect_enabled; /* true only if associated ect device is
>>> enabled */
>>> /* system configuration and feature lists */
>>> struct list_head feature_csdev_list;
>>> struct list_head config_csdev_list;
>>> @@ -378,23 +364,11 @@ struct coresight_ops_helper {
>>> int (*disable)(struct coresight_device *csdev, void *data);
>>> };
>>> -/**
>>> - * struct coresight_ops_ect - Ops for an embedded cross trigger device
>>> - *
>>> - * @enable : Enable the device
>>> - * @disable : Disable the device
>>> - */
>>> -struct coresight_ops_ect {
>>> - int (*enable)(struct coresight_device *csdev);
>>> - int (*disable)(struct coresight_device *csdev);
>>> -};
>>> -
>>> struct coresight_ops {
>>> const struct coresight_ops_sink *sink_ops;
>>> const struct coresight_ops_link *link_ops;
>>> const struct coresight_ops_source *source_ops;
>>> const struct coresight_ops_helper *helper_ops;
>>> - const struct coresight_ops_ect *ect_ops;
>>> };
>>> #if IS_ENABLED(CONFIG_CORESIGHT)
>>