Re: [PATCH v5 4/7] remoteproc: core introduce rproc_set_rsc_table_on_start function

[Mathieu Poirier]

On Tue, May 21, 2024 at 10:09:58AM +0200, Arnaud Pouliquen wrote:
> Split rproc_start()to prepare the update of the management of

I don't see any "splitting" for rproc_start() in this patch.  Please consider
rewording or removing.

> the cache table on start, for the support of the firmware loading
> by the TEE interface.
> - create rproc_set_rsc_table_on_start() to address the management of
>   the cache table in a specific function, as done in
>   rproc_reset_rsc_table_on_stop().
> - rename rproc_set_rsc_table in rproc_set_rsc_table_on_attach()
> - move rproc_reset_rsc_table_on_stop() to be close to the
>   rproc_set_rsc_table_on_start() function

This patch is really hard to read due to all 3 operations happening at the same
time.  Please split in 3 smaller patches.

> 
> Suggested-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxxxxxxx>
> ---
>  drivers/remoteproc/remoteproc_core.c | 116 ++++++++++++++-------------
>  1 file changed, 62 insertions(+), 54 deletions(-)
> 
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index f276956f2c5c..42bca01f3bde 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -1264,18 +1264,9 @@ void rproc_resource_cleanup(struct rproc *rproc)
>  }
>  EXPORT_SYMBOL(rproc_resource_cleanup);
>  
> -static int rproc_start(struct rproc *rproc, const struct firmware *fw)
> +static int rproc_set_rsc_table_on_start(struct rproc *rproc, const struct firmware *fw)
>  {
>  	struct resource_table *loaded_table;
> -	struct device *dev = &rproc->dev;
> -	int ret;
> -
> -	/* load the ELF segments to memory */
> -	ret = rproc_load_segments(rproc, fw);
> -	if (ret) {
> -		dev_err(dev, "Failed to load program segments: %d\n", ret);
> -		return ret;
> -	}
>  
>  	/*
>  	 * The starting device has been given the rproc->cached_table as the
> @@ -1291,6 +1282,64 @@ static int rproc_start(struct rproc *rproc, const struct firmware *fw)
>  		rproc->table_ptr = loaded_table;
>  	}
>  
> +	return 0;
> +}
> +
> +static int rproc_reset_rsc_table_on_stop(struct rproc *rproc)
> +{
> +	/* A resource table was never retrieved, nothing to do here */
> +	if (!rproc->table_ptr)
> +		return 0;
> +
> +	/*
> +	 * If a cache table exists the remote processor was started by
> +	 * the remoteproc core.  That cache table should be used for
> +	 * the rest of the shutdown process.
> +	 */
> +	if (rproc->cached_table)
> +		goto out;
> +
> +	/*
> +	 * If we made it here the remote processor was started by another
> +	 * entity and a cache table doesn't exist.  As such make a copy of
> +	 * the resource table currently used by the remote processor and
> +	 * use that for the rest of the shutdown process.  The memory
> +	 * allocated here is free'd in rproc_shutdown().
> +	 */
> +	rproc->cached_table = kmemdup(rproc->table_ptr,
> +				      rproc->table_sz, GFP_KERNEL);
> +	if (!rproc->cached_table)
> +		return -ENOMEM;
> +
> +	/*
> +	 * Since the remote processor is being switched off the clean table
> +	 * won't be needed.  Allocated in rproc_set_rsc_table_on_start().
> +	 */
> +	kfree(rproc->clean_table);
> +
> +out:
> +	/*
> +	 * Use a copy of the resource table for the remainder of the
> +	 * shutdown process.
> +	 */
> +	rproc->table_ptr = rproc->cached_table;
> +	return 0;
> +}
> +
> +static int rproc_start(struct rproc *rproc, const struct firmware *fw)
> +{
> +	struct device *dev = &rproc->dev;
> +	int ret;
> +
> +	/* load the ELF segments to memory */
> +	ret = rproc_load_segments(rproc, fw);
> +	if (ret) {
> +		dev_err(dev, "Failed to load program segments: %d\n", ret);
> +		return ret;
> +	}
> +
> +	rproc_set_rsc_table_on_start(rproc, fw);
> +
>  	ret = rproc_prepare_subdevices(rproc);
>  	if (ret) {
>  		dev_err(dev, "failed to prepare subdevices for %s: %d\n",
> @@ -1450,7 +1499,7 @@ static int rproc_fw_boot(struct rproc *rproc, const struct firmware *fw)
>  	return ret;
>  }
>  
> -static int rproc_set_rsc_table(struct rproc *rproc)
> +static int rproc_set_rsc_table_on_attach(struct rproc *rproc)
>  {
>  	struct resource_table *table_ptr;
>  	struct device *dev = &rproc->dev;
> @@ -1540,54 +1589,13 @@ static int rproc_reset_rsc_table_on_detach(struct rproc *rproc)
>  
>  	/*
>  	 * The clean resource table is no longer needed.  Allocated in
> -	 * rproc_set_rsc_table().
> +	 * rproc_set_rsc_table_on_attach().
>  	 */
>  	kfree(rproc->clean_table);
>  
>  	return 0;
>  }
>  
> -static int rproc_reset_rsc_table_on_stop(struct rproc *rproc)
> -{
> -	/* A resource table was never retrieved, nothing to do here */
> -	if (!rproc->table_ptr)
> -		return 0;
> -
> -	/*
> -	 * If a cache table exists the remote processor was started by
> -	 * the remoteproc core.  That cache table should be used for
> -	 * the rest of the shutdown process.
> -	 */
> -	if (rproc->cached_table)
> -		goto out;
> -
> -	/*
> -	 * If we made it here the remote processor was started by another
> -	 * entity and a cache table doesn't exist.  As such make a copy of
> -	 * the resource table currently used by the remote processor and
> -	 * use that for the rest of the shutdown process.  The memory
> -	 * allocated here is free'd in rproc_shutdown().
> -	 */
> -	rproc->cached_table = kmemdup(rproc->table_ptr,
> -				      rproc->table_sz, GFP_KERNEL);
> -	if (!rproc->cached_table)
> -		return -ENOMEM;
> -
> -	/*
> -	 * Since the remote processor is being switched off the clean table
> -	 * won't be needed.  Allocated in rproc_set_rsc_table().
> -	 */
> -	kfree(rproc->clean_table);
> -
> -out:
> -	/*
> -	 * Use a copy of the resource table for the remainder of the
> -	 * shutdown process.
> -	 */
> -	rproc->table_ptr = rproc->cached_table;
> -	return 0;
> -}
> -
>  /*
>   * Attach to remote processor - similar to rproc_fw_boot() but without
>   * the steps that deal with the firmware image.
> @@ -1614,7 +1622,7 @@ static int rproc_attach(struct rproc *rproc)
>  		goto disable_iommu;
>  	}
>  
> -	ret = rproc_set_rsc_table(rproc);
> +	ret = rproc_set_rsc_table_on_attach(rproc);
>  	if (ret) {
>  		dev_err(dev, "can't load resource table: %d\n", ret);
>  		goto unprepare_device;
> -- 
> 2.25.1
>