diff mbox series

[v3,14/40] cxl/core: Track port depth

Message ID 164298419321.3018233.4469731547378993606.stgit@dwillia2-desk3.amr.corp.intel.com (mailing list archive)
State Not Applicable
Delegated to: Bjorn Helgaas
Headers show
Series CXL.mem Topology Discovery and Hotplug Support | expand

Commit Message

Dan Williams Jan. 24, 2022, 12:29 a.m. UTC 
From: Ben Widawsky <ben.widawsky@intel.com>

In preparation for proving CXL subsystem usage of the device_lock()
order track the depth of ports with the expectation that  shallower port
locks can be held over deeper port locks.

Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
---
 drivers/cxl/core/port.c |    2 ++
 drivers/cxl/cxl.h       |    2 ++
 2 files changed, 4 insertions(+)

Comments

Jonathan Cameron Jan. 31, 2022, 2:57 p.m. UTC | #1 
On Sun, 23 Jan 2022 16:29:53 -0800
Dan Williams <dan.j.williams@intel.com> wrote:

> From: Ben Widawsky <ben.widawsky@intel.com>
> 
> In preparation for proving CXL subsystem usage of the device_lock()
> order track the depth of ports with the expectation that  shallower port

It's nitpick Monday: double space before shallower.

> locks can be held over deeper port locks.
> 
> Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
> Signed-off-by: Dan Williams <dan.j.williams@intel.com>

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

> ---
>  drivers/cxl/core/port.c |    2 ++
>  drivers/cxl/cxl.h       |    2 ++
>  2 files changed, 4 insertions(+)
> 
> diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
> index 826b300ba950..4ec5febf73fb 100644
> --- a/drivers/cxl/core/port.c
> +++ b/drivers/cxl/core/port.c
> @@ -362,6 +362,8 @@ struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
>  	if (IS_ERR(port))
>  		return port;
>  
> +	if (parent_port)
> +		port->depth = parent_port->depth + 1;
>  	dev = &port->dev;
>  	if (parent_port)
>  		rc = dev_set_name(dev, "port%d", port->id);
> diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
> index e60878ab4569..c1dc53492773 100644
> --- a/drivers/cxl/cxl.h
> +++ b/drivers/cxl/cxl.h
> @@ -252,6 +252,7 @@ struct cxl_walk_context {
>   * @dports: cxl_dport instances referenced by decoders
>   * @decoder_ida: allocator for decoder ids
>   * @component_reg_phys: component register capability base address (optional)
> + * @depth: How deep this port is relative to the root. depth 0 is the root.
>   */
>  struct cxl_port {
>  	struct device dev;
> @@ -260,6 +261,7 @@ struct cxl_port {
>  	struct list_head dports;
>  	struct ida decoder_ida;
>  	resource_size_t component_reg_phys;
> +	unsigned int depth;
>  };
>  
>  /**
>
diff mbox series

Patch

diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c
index 826b300ba950..4ec5febf73fb 100644
--- a/drivers/cxl/core/port.c
+++ b/drivers/cxl/core/port.c
@@ -362,6 +362,8 @@  struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
 	if (IS_ERR(port))
 		return port;
 
+	if (parent_port)
+		port->depth = parent_port->depth + 1;
 	dev = &port->dev;
 	if (parent_port)
 		rc = dev_set_name(dev, "port%d", port->id);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index e60878ab4569..c1dc53492773 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -252,6 +252,7 @@  struct cxl_walk_context {
  * @dports: cxl_dport instances referenced by decoders
  * @decoder_ida: allocator for decoder ids
  * @component_reg_phys: component register capability base address (optional)
+ * @depth: How deep this port is relative to the root. depth 0 is the root.
  */
 struct cxl_port {
 	struct device dev;
@@ -260,6 +261,7 @@  struct cxl_port {
 	struct list_head dports;
 	struct ida decoder_ida;
 	resource_size_t component_reg_phys;
+	unsigned int depth;
 };
 
 /**