diff mbox series

[NDCTL] cxl/region: Always use the correct target position

Message ID 20230630151245.1318-1-yangx.jy@fujitsu.com
State New, archived
Headers show
Series [NDCTL] cxl/region: Always use the correct target position | expand

Commit Message

Xiao Yang June 30, 2023, 3:12 p.m. UTC
create_region() uses the wrong target position in some cases.
For example, cxl create-region command fails to create a new
region in 2 way interleave set when mem0 connects target1(position:1)
and mem1 connects target0(position:0):

$ cxl list -M -P -D -T -u
[
  {
    "ports":[
      {
        "port":"port1",
        "host":"pci0000:16",
        "depth":1,
        "nr_dports":1,
        "dports":[
          {
            "dport":"0000:16:00.0",
            "id":"0"
          }
        ],
        "memdevs:port1":[
          {
            "memdev":"mem0",
            "ram_size":"512.00 MiB (536.87 MB)",
            "serial":"0",
            "host":"0000:17:00.0"
          }
        ]
      },
      {
        "port":"port2",
        "host":"pci0000:0c",
        "depth":1,
        "nr_dports":1,
        "dports":[
          {
            "dport":"0000:0c:00.0",
            "id":"0"
          }
        ],
        "memdevs:port2":[
          {
            "memdev":"mem1",
            "ram_size":"512.00 MiB (536.87 MB)",
            "serial":"0",
            "host":"0000:0d:00.0"
          }
        ]
      }
    ]
  },
  {
    "root decoders":[
      {
        "decoder":"decoder0.0",
        "resource":"0x750000000",
        "size":"4.00 GiB (4.29 GB)",
        "interleave_ways":2,
        "interleave_granularity":8192,
        "max_available_extent":"4.00 GiB (4.29 GB)",
        "pmem_capable":true,
        "volatile_capable":true,
        "accelmem_capable":true,
        "nr_targets":2,
        "targets":[
          {
            "target":"pci0000:16",
            "alias":"ACPI0016:00",
            "position":1,
            "id":"0x16"
          },
          {
            "target":"pci0000:0c",
            "alias":"ACPI0016:01",
            "position":0,
            "id":"0xc"
          }
        ]
      }
    ]
  }
]

$ cxl create-region -t ram -d decoder0.0 -m mem0 mem1
cxl region: create_region: region0: failed to set target0 to mem0
cxl region: cmd_create_region: created 0 regions

Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
---
 cxl/region.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

Comments

Xiao Yang July 9, 2023, 11:50 a.m. UTC | #1
Hi all,

Kindly ping.

This patch can only fixes the case that 2 way interleave is enabled 
across 2 CXL host bridges and each host bridge has 1 CXL Root Port.
PS: In other word, this patch is wrong when 2 way interleave is enabled 
across 2 CXL host bridges and each host bridge has 2 CXL Root Ports.

I am trying to find a better solution. If you have any suggestion, 
please let me know.

Best Regards,
Xiao Yang

On 2023/6/30 23:12, Xiao Yang wrote:
> create_region() uses the wrong target position in some cases.
> For example, cxl create-region command fails to create a new
> region in 2 way interleave set when mem0 connects target1(position:1)
> and mem1 connects target0(position:0):
> 
> $ cxl list -M -P -D -T -u
> [
>    {
>      "ports":[
>        {
>          "port":"port1",
>          "host":"pci0000:16",
>          "depth":1,
>          "nr_dports":1,
>          "dports":[
>            {
>              "dport":"0000:16:00.0",
>              "id":"0"
>            }
>          ],
>          "memdevs:port1":[
>            {
>              "memdev":"mem0",
>              "ram_size":"512.00 MiB (536.87 MB)",
>              "serial":"0",
>              "host":"0000:17:00.0"
>            }
>          ]
>        },
>        {
>          "port":"port2",
>          "host":"pci0000:0c",
>          "depth":1,
>          "nr_dports":1,
>          "dports":[
>            {
>              "dport":"0000:0c:00.0",
>              "id":"0"
>            }
>          ],
>          "memdevs:port2":[
>            {
>              "memdev":"mem1",
>              "ram_size":"512.00 MiB (536.87 MB)",
>              "serial":"0",
>              "host":"0000:0d:00.0"
>            }
>          ]
>        }
>      ]
>    },
>    {
>      "root decoders":[
>        {
>          "decoder":"decoder0.0",
>          "resource":"0x750000000",
>          "size":"4.00 GiB (4.29 GB)",
>          "interleave_ways":2,
>          "interleave_granularity":8192,
>          "max_available_extent":"4.00 GiB (4.29 GB)",
>          "pmem_capable":true,
>          "volatile_capable":true,
>          "accelmem_capable":true,
>          "nr_targets":2,
>          "targets":[
>            {
>              "target":"pci0000:16",
>              "alias":"ACPI0016:00",
>              "position":1,
>              "id":"0x16"
>            },
>            {
>              "target":"pci0000:0c",
>              "alias":"ACPI0016:01",
>              "position":0,
>              "id":"0xc"
>            }
>          ]
>        }
>      ]
>    }
> ]
> 
> $ cxl create-region -t ram -d decoder0.0 -m mem0 mem1
> cxl region: create_region: region0: failed to set target0 to mem0
> cxl region: cmd_create_region: created 0 regions
> 
> Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
> ---
>   cxl/region.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/cxl/region.c b/cxl/region.c
> index 07ce4a3..946b5ff 100644
> --- a/cxl/region.c
> +++ b/cxl/region.c
> @@ -667,6 +667,8 @@ static int create_region(struct cxl_ctx *ctx, int *count,
>   		struct json_object *jobj =
>   			json_object_array_get_idx(p->memdevs, i);
>   		struct cxl_memdev *memdev = json_object_get_userdata(jobj);
> +		struct cxl_target *target = cxl_decoder_get_target_by_memdev(p->root_decoder,
> +										memdev);
>   
>   		ep_decoder = cxl_memdev_find_decoder(memdev);
>   		if (!ep_decoder) {
> @@ -683,7 +685,7 @@ static int create_region(struct cxl_ctx *ctx, int *count,
>   			try(cxl_decoder, set_mode, ep_decoder, p->mode);
>   		}
>   		try(cxl_decoder, set_dpa_size, ep_decoder, size/p->ways);
> -		rc = cxl_region_set_target(region, i, ep_decoder);
> +		rc = cxl_region_set_target(region, cxl_target_get_position(target), ep_decoder);
>   		if (rc) {
>   			log_err(&rl, "%s: failed to set target%d to %s\n",
>   				devname, i, cxl_memdev_get_devname(memdev));
Verma, Vishal L July 24, 2023, 9:16 p.m. UTC | #2
On Sun, 2023-07-09 at 19:50 +0800, Xiao Yang wrote:
> Hi all,
> 
> Kindly ping.
> 
> This patch can only fixes the case that 2 way interleave is enabled 
> across 2 CXL host bridges and each host bridge has 1 CXL Root Port.
> PS: In other word, this patch is wrong when 2 way interleave is enabled 
> across 2 CXL host bridges and each host bridge has 2 CXL Root Ports.
> 
> I am trying to find a better solution. If you have any suggestion, 
> please let me know.

Hi Xiao,

The current behavior is that if a list of memdevs is supplied on the
command line, then that ordering is how the targets are assigned. The
plan is to eventually add a mode where cxl-create-region is allowed to
reorder the memdevs to fit the target rules. This should fix the issue
you are hitting, but that's a bigger piece of work. For now the
workaround is that if the automatic ordering fails (and it isn't
guaranteed to work), figure out the right ordering externally (using
cxl-list) and feed the correct order to cxl-create-region.

> 
> Best Regards,
> Xiao Yang
> 
> On 2023/6/30 23:12, Xiao Yang wrote:
> > create_region() uses the wrong target position in some cases.
> > For example, cxl create-region command fails to create a new
> > region in 2 way interleave set when mem0 connects target1(position:1)
> > and mem1 connects target0(position:0):
> > 
> > $ cxl list -M -P -D -T -u
> > [
> >    {
> >      "ports":[
> >        {
> >          "port":"port1",
> >          "host":"pci0000:16",
> >          "depth":1,
> >          "nr_dports":1,
> >          "dports":[
> >            {
> >              "dport":"0000:16:00.0",
> >              "id":"0"
> >            }
> >          ],
> >          "memdevs:port1":[
> >            {
> >              "memdev":"mem0",
> >              "ram_size":"512.00 MiB (536.87 MB)",
> >              "serial":"0",
> >              "host":"0000:17:00.0"
> >            }
> >          ]
> >        },
> >        {
> >          "port":"port2",
> >          "host":"pci0000:0c",
> >          "depth":1,
> >          "nr_dports":1,
> >          "dports":[
> >            {
> >              "dport":"0000:0c:00.0",
> >              "id":"0"
> >            }
> >          ],
> >          "memdevs:port2":[
> >            {
> >              "memdev":"mem1",
> >              "ram_size":"512.00 MiB (536.87 MB)",
> >              "serial":"0",
> >              "host":"0000:0d:00.0"
> >            }
> >          ]
> >        }
> >      ]
> >    },
> >    {
> >      "root decoders":[
> >        {
> >          "decoder":"decoder0.0",
> >          "resource":"0x750000000",
> >          "size":"4.00 GiB (4.29 GB)",
> >          "interleave_ways":2,
> >          "interleave_granularity":8192,
> >          "max_available_extent":"4.00 GiB (4.29 GB)",
> >          "pmem_capable":true,
> >          "volatile_capable":true,
> >          "accelmem_capable":true,
> >          "nr_targets":2,
> >          "targets":[
> >            {
> >              "target":"pci0000:16",
> >              "alias":"ACPI0016:00",
> >              "position":1,
> >              "id":"0x16"
> >            },
> >            {
> >              "target":"pci0000:0c",
> >              "alias":"ACPI0016:01",
> >              "position":0,
> >              "id":"0xc"
> >            }
> >          ]
> >        }
> >      ]
> >    }
> > ]
> > 
> > $ cxl create-region -t ram -d decoder0.0 -m mem0 mem1
> > cxl region: create_region: region0: failed to set target0 to mem0
> > cxl region: cmd_create_region: created 0 regions
> > 
> > Signed-off-by: Xiao Yang <yangx.jy@fujitsu.com>
> > ---
> >   cxl/region.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/cxl/region.c b/cxl/region.c
> > index 07ce4a3..946b5ff 100644
> > --- a/cxl/region.c
> > +++ b/cxl/region.c
> > @@ -667,6 +667,8 @@ static int create_region(struct cxl_ctx *ctx, int *count,
> >                 struct json_object *jobj =
> >                         json_object_array_get_idx(p->memdevs, i);
> >                 struct cxl_memdev *memdev = json_object_get_userdata(jobj);
> > +               struct cxl_target *target = cxl_decoder_get_target_by_memdev(p->root_decoder,
> > +                                                                               memdev);
> >   
> >                 ep_decoder = cxl_memdev_find_decoder(memdev);
> >                 if (!ep_decoder) {
> > @@ -683,7 +685,7 @@ static int create_region(struct cxl_ctx *ctx, int *count,
> >                         try(cxl_decoder, set_mode, ep_decoder, p->mode);
> >                 }
> >                 try(cxl_decoder, set_dpa_size, ep_decoder, size/p->ways);
> > -               rc = cxl_region_set_target(region, i, ep_decoder);
> > +               rc = cxl_region_set_target(region, cxl_target_get_position(target), ep_decoder);
> >                 if (rc) {
> >                         log_err(&rl, "%s: failed to set target%d to %s\n",
> >                                 devname, i, cxl_memdev_get_devname(memdev));
diff mbox series

Patch

diff --git a/cxl/region.c b/cxl/region.c
index 07ce4a3..946b5ff 100644
--- a/cxl/region.c
+++ b/cxl/region.c
@@ -667,6 +667,8 @@  static int create_region(struct cxl_ctx *ctx, int *count,
 		struct json_object *jobj =
 			json_object_array_get_idx(p->memdevs, i);
 		struct cxl_memdev *memdev = json_object_get_userdata(jobj);
+		struct cxl_target *target = cxl_decoder_get_target_by_memdev(p->root_decoder,
+										memdev);
 
 		ep_decoder = cxl_memdev_find_decoder(memdev);
 		if (!ep_decoder) {
@@ -683,7 +685,7 @@  static int create_region(struct cxl_ctx *ctx, int *count,
 			try(cxl_decoder, set_mode, ep_decoder, p->mode);
 		}
 		try(cxl_decoder, set_dpa_size, ep_decoder, size/p->ways);
-		rc = cxl_region_set_target(region, i, ep_decoder);
+		rc = cxl_region_set_target(region, cxl_target_get_position(target), ep_decoder);
 		if (rc) {
 			log_err(&rl, "%s: failed to set target%d to %s\n",
 				devname, i, cxl_memdev_get_devname(memdev));