Re: [PATCH v5 2/2] coresight: core: Disable helpers for devices that fail to enable

[Leo Yan <leo.yan@arm.com>]

On Tue, Apr 29, 2025 at 04:13:00PM -0700, Yabin Cui wrote:
> When enabling a SINK or LINK type coresight device fails, the
> associated helpers should be disabled.
> 
> Signed-off-by: Yabin Cui <yabinc@google.com>
> Suggested-by: Suzuki K Poulose <suzuki.poulose@arm.com>
> Reviewed-by: James Clark <james.clark@linaro.org>
> Reviewed-by: Mike Leach <mike.leach@linaro.org>

Reviewed-by: Leo Yan <leo.yan@arm.com>

> ---
>  drivers/hwtracing/coresight/coresight-core.c | 15 ++++++++++-----
>  1 file changed, 10 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
> index dabec7073aed..d3523f0262af 100644
> --- a/drivers/hwtracing/coresight/coresight-core.c
> +++ b/drivers/hwtracing/coresight/coresight-core.c
> @@ -465,7 +465,7 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode,
>  		/* Enable all helpers adjacent to the path first */
>  		ret = coresight_enable_helpers(csdev, mode, path);
>  		if (ret)
> -			goto err;
> +			goto err_disable_path;
>  		/*
>  		 * ETF devices are tricky... They can be a link or a sink,
>  		 * depending on how they are configured.  If an ETF has been
> @@ -486,8 +486,10 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode,
>  			 * that need disabling. Disabling the path here
>  			 * would mean we could disrupt an existing session.
>  			 */
> -			if (ret)
> +			if (ret) {
> +				coresight_disable_helpers(csdev, path);
>  				goto out;
> +			}
>  			break;
>  		case CORESIGHT_DEV_TYPE_SOURCE:
>  			/* sources are enabled from either sysFS or Perf */
> @@ -497,16 +499,19 @@ int coresight_enable_path(struct coresight_path *path, enum cs_mode mode,
>  			child = list_next_entry(nd, link)->csdev;
>  			ret = coresight_enable_link(csdev, parent, child, source);
>  			if (ret)
> -				goto err;
> +				goto err_disable_helpers;
>  			break;
>  		default:
> -			goto err;
> +			ret = -EINVAL;
> +			goto err_disable_helpers;
>  		}
>  	}
>  
>  out:
>  	return ret;
> -err:
> +err_disable_helpers:
> +	coresight_disable_helpers(csdev, path);
> +err_disable_path:
>  	coresight_disable_path_from(path, nd);
>  	goto out;
>  }
> -- 
> 2.49.0.967.g6a0df3ecc3-goog
>