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Message-ID: <61bb4e6d-5451-2f01-19b2-76c396854c23@arm.com>
Date:   Tue, 4 Apr 2023 13:55:22 +0100
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Subject: Re: [PATCH v3 13/13] coresight: Fix CTI module refcount leak by
 making it a helper device
Content-Language: en-US
To:     Suzuki K Poulose <suzuki.poulose@arm.com>,
        coresight@lists.linaro.org, quic_jinlmao@quicinc.com,
        mike.leach@linaro.org
Cc:     Mathieu Poirier <mathieu.poirier@linaro.org>,
        Leo Yan <leo.yan@linaro.org>,
        Alexander Shishkin <alexander.shishkin@linux.intel.com>,
        Maxime Coquelin <mcoquelin.stm32@gmail.com>,
        Alexandre Torgue <alexandre.torgue@foss.st.com>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        linux-stm32@st-md-mailman.stormreply.com
References: <20230329115329.2747724-1-james.clark@arm.com>
 <20230329115329.2747724-14-james.clark@arm.com>
 <77d890a9-9927-da8e-1460-54513784683d@arm.com>
From:   James Clark <james.clark@arm.com>
In-Reply-To: <77d890a9-9927-da8e-1460-54513784683d@arm.com>
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Precedence: bulk


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@arm.com>
>> ---
>>   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.

>>   {
>> +    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)
>