Documentation, dt, numa: Add note to empty NUMA node
PATCH v4 1/1 Documentation, dt, numa: Add note to empty NUMA node
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)
Documentation/devicetree/bindings/numa.txt +4 -0
@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards. + memory@c00000 { device_type = "memory"; reg = <0x0 0xc00000 0x0 0x80000000>;
Signature · 1 line
2.23.0
Quoted 9 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>
Thanks.
Quoted 20 lines
--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +4
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards. + memory@c00000 { device_type = "memory"; reg = <0x0 0xc00000 0x0 0x80000000>;
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0
Documentation/devicetree/bindings/numa.txt Example: · line 114
Quoted 6 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.
Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Thanks,
drew
Quoted 7 lines
Documentation/devicetree/bindings/numa.txt +1
-0+ memory@c00000 { device_type = "memory"; reg = <0x0 0xc00000 0x0 0x80000000>;Signature · 1 line
2.23.0
Quoted 28 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 114
Quoted 6 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
Quoted 8 lines
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 14 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Thanks,
drewQuoted 7 lines
Documentation/devicetree/bindings/numa.txt +1
-0+ memory@c00000 { device_type = "memory"; reg = <0x0 0xc00000 0x0 0x80000000>;Signature · 1 line
2.23.0
Quoted 32 lines · Andrew Jones
Quoted 31 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 114
Quoted 6 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
Quoted 12 lines
Quoted 5 lines
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 4 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Drew, thanks for your comments. Yeah, it sounds sensible to create a new section for it and an example would be more helpful. Please check if below changes are fine to you. I probably need Randy's review again.
I'm trying to avoid too many revisions for this sort of trivial patch, even though I already had. However, it's time frame for v5.14 and I'm pushing this to be merged during the cycle.
Documentation/devicetree/bindings/numa.txt +59 -1
@@ -103,7 +103,65 @@ Example: }; ============================================================================== -4 - Example dts +4 - Empty memory node +============================================================================== + +Empty memory nodes, which no memory resides in, are allowed. The 'length' +field of 'reg' property is zero, but 'base-address' is dummy and invalid +for these empty memory nodes. However, the NUMA node IDs and distance maps +for them are still valid, but memory may be added into them through hotplug +afterwards. + +Example: + + memory@0 { + device_type = "memory"; + reg = <0x0 0x0 0x0 0x80000000>; + numa-node-id = <0>; + }; + + memory@0x80000000 { + device_type = "memory"; + reg = <0x0 0x80000000 0x0 0x80000000>; + numa-node-id = <1>; + }; + + /* Empty memory node */ + memory@0x100000000 { + device_type = "memory"; + reg = <0x1 0x0 0x0 0x0>; + numa-node-id = <2>; + }; + + /* Empty memory node */ + memory@0x180000000 { + device_type = "memory"; + reg = <0x1 0x80000000 0x0 0x0>; + numa-node-id = <3>; + }; + + distance-map { + compatible = "numa-distance-map-v1"; + distance-matrix = <0 0 10>, + <0 1 20>, + <0 2 40>, + <0 3 20>, + <1 0 20>, + <1 1 10>, + <1 2 20>, + <1 3 40>, + <2 0 40>, + <2 1 20>, + <2 2 10>, + <2 3 20>, + <3 0 20>, + <3 1 40>, + <3 2 20>, + <3 3 10>; + }; + +============================================================================== +5 - Example dts ============================================================================== Dual socket system consists of 2 boards connected through ccn bus and
Thanks,
Gavin
Quoted 45 lines · Gavin Shan
Quoted 31 lines · Andrew Jones
Quoted 30 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 113
Quoted 5 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
Quoted 12 lines
Quoted 5 lines
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 4 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Quoted 8 lines
Drew, thanks for your comments. Yeah, it sounds sensible to create a new section for it and an example would be more helpful. Please check if below changes are fine to you. I probably need Randy's review again.
I'm trying to avoid too many revisions for this sort of trivial patch, even though I already had. However, it's time frame for v5.14 and I'm pushing this to be merged during the cycle.
We must revise until we're satisfied... Also, I wouldn't call writing specifications trivial.
Documentation/devicetree/bindings/numa.txt Example: · line 105
Quoted 8 lines
Documentation/devicetree/bindings/numa.txt +1
-1@@ -103,7 +103,65 @@ Example: }; ============================================================================== -4 - Example dts +4 - Empty memory node
nodes
Documentation/devicetree/bindings/numa.txt Example: · line 110
Quoted 4 lines
Documentation/devicetree/bindings/numa.txt +4
-0+============================================================================== + +Empty memory nodes, which no memory resides in, are allowed. The 'length' +field of 'reg' property is zero, but 'base-address' is dummy and invalid
is a dummy address and is invalid.
Documentation/devicetree/bindings/numa.txt Example: · line 110
Quoted 1 line
Documentation/devicetree/bindings/numa.txt +1
-0+for these empty memory nodes.
Can drop this "for these empty memory nodes" that's clear from the context.
Quoted 2 lines
However, the NUMA node IDs and distance maps
+for them are still valid, but memory may be added into them through hotplug
^ drop 'for them' ^ Again, this should be "and". "but" is a
contrastive conjunction. We want to express that the nodes are valid *and* may have memory hotplugged later.
Quoted 1 line
+afterwards.
I'll just rewrite it:
Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
Quoted 6 lines
Documentation/devicetree/bindings/numa.txt +6
-0+ +Example: + + memory@0 { + device_type = "memory"; + reg = <0x0 0x0 0x0 0x80000000>;
Documentation/devicetree/bindings/numa.txt Example: · line 129
Quoted 10 lines
Documentation/devicetree/bindings/numa.txt +10
-0+ numa-node-id = <0>; + }; + + memory@0x80000000 { + device_type = "memory"; + reg = <0x0 0x80000000 0x0 0x80000000>; + numa-node-id = <1>; + }; + + /* Empty memory node */
You should write how you've selected the dummy addresses for the empty memory nodes, perhaps here in the /* Empty memory node */ comments or above in the paragraph or both.
Quoted 39 lines
Documentation/devicetree/bindings/numa.txt +35
-0+ memory@0x100000000 { + device_type = "memory"; + reg = <0x1 0x0 0x0 0x0>; + numa-node-id = <2>; + }; + + /* Empty memory node */ + memory@0x180000000 { + device_type = "memory"; + reg = <0x1 0x80000000 0x0 0x0>; + numa-node-id = <3>; + }; + + distance-map { + compatible = "numa-distance-map-v1"; + distance-matrix = <0 0 10>, + <0 1 20>, + <0 2 40>, + <0 3 20>, + <1 0 20>, + <1 1 10>, + <1 2 20>, + <1 3 40>, + <2 0 40>, + <2 1 20>, + <2 2 10>, + <2 3 20>, + <3 0 20>, + <3 1 40>, + <3 2 20>, + <3 3 10>; + }; + +============================================================================== +5 - Example dts ============================================================================== Dual socket system consists of 2 boards connected through ccn bus and
Quoted 4 lines
Thanks,
Gavin
Thanks,
drew
Quoted 58 lines · Andrew Jones
Quoted 45 lines · Gavin Shan
Quoted 31 lines · Andrew Jones
Quoted 30 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 113
Quoted 5 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
Quoted 12 lines
Quoted 5 lines
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 4 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Quoted 8 lines
Drew, thanks for your comments. Yeah, it sounds sensible to create a new section for it and an example would be more helpful. Please check if below changes are fine to you. I probably need Randy's review again.
I'm trying to avoid too many revisions for this sort of trivial patch, even though I already had. However, it's time frame for v5.14 and I'm pushing this to be merged during the cycle.
We must revise until we're satisfied... Also, I wouldn't call writing specifications trivial.
[...]
Quoted 7 lines
I'll just rewrite it:
Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
[...]
Quoted 5 lines
You should write how you've selected the dummy addresses for the empty memory nodes, perhaps here in the /* Empty memory node */ comments or above in the paragraph or both.
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt Example: · line 142
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt +13
-0+ memory@0x100000000 { + device_type = "memory"; + reg = <0x1 0x0 0x0 0x0>; + numa-node-id = <2>; + }; + + /* Empty memory node */ + memory@0x180000000 { + device_type = "memory"; + reg = <0x1 0x80000000 0x0 0x0>; + numa-node-id = <3>; + }; +
[...]
Thanks, Drew. As 'base-address' is dummy address and invalid. So we would note it as suggestion. With your suggestion integrated, how about something like this?
==============================================================================
4 - Empty memory nodes
==============================================================================
Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. The 'base-address' could be the summation of highest memory address plus the NUMA node ID. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
:
memory@0 {
device_type = "memory";
reg = <0x0 0x0 0x0 0x80000000>;
numa-node-id = <0>;
};
memory@0x80000000 {
device_type = "memory";
reg = <0x0 0x80000000 0x0 0x80000000>;
numa-node-id = <1>;
};
/* Empty memory node */
memory@0x100000002 {
device_type = "memory";
reg = <0x1 0x2 0x0 0x0>;
numa-node-id = <2>;
};
/* Empty memory node */
memory@0x100000003 {
device_type = "memory";
reg = <0x1 0x3 0x0 0x0>;
numa-node-id = <3>;
};
:Thanks,
Gavin
Quoted 138 lines · Gavin Shan
Quoted 58 lines · Andrew Jones
Quoted 45 lines · Gavin Shan
Quoted 31 lines · Andrew Jones
Quoted 30 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 113
Quoted 5 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
Quoted 12 lines
Quoted 5 lines
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 4 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Quoted 8 lines
Drew, thanks for your comments. Yeah, it sounds sensible to create a new section for it and an example would be more helpful. Please check if below changes are fine to you. I probably need Randy's review again.
I'm trying to avoid too many revisions for this sort of trivial patch, even though I already had. However, it's time frame for v5.14 and I'm pushing this to be merged during the cycle.
We must revise until we're satisfied... Also, I wouldn't call writing specifications trivial.
[...]
Quoted 7 lines
I'll just rewrite it:
Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
[...]
Quoted 5 lines
You should write how you've selected the dummy addresses for the empty memory nodes, perhaps here in the /* Empty memory node */ comments or above in the paragraph or both.
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt Example: · line 142
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt +13
-0+ memory@0x100000000 { + device_type = "memory"; + reg = <0x1 0x0 0x0 0x0>; + numa-node-id = <2>; + }; + + /* Empty memory node */ + memory@0x180000000 { + device_type = "memory"; + reg = <0x1 0x80000000 0x0 0x0>; + numa-node-id = <3>; + }; +[...]
Thanks, Drew. As 'base-address' is dummy address and invalid. So we would note it as suggestion. With your suggestion integrated, how about something like this?
==============================================================================
4 - Empty memory nodes
==============================================================================Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. The 'base-address' could be the summation of highest memory address plus the NUMA node ID. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
: memory@0 { device_type = "memory"; reg = <0x0 0x0 0x0 0x80000000>; numa-node-id = <0>; }; memory@0x80000000 { device_type = "memory"; reg = <0x0 0x80000000 0x0 0x80000000>; numa-node-id = <1>; }; /* Empty memory node */ memory@0x100000002 { device_type = "memory"; reg = <0x1 0x2 0x0 0x0>; numa-node-id = <2>; }; /* Empty memory node */ memory@0x100000003 { device_type = "memory"; reg = <0x1 0x3 0x0 0x0>; numa-node-id = <3>; }; :
Quoted 4 lines
Thanks,
Gavin
Looks good to me.
Thanks,
drew
Quoted 137 lines · Andrew Jones
Quoted 136 lines · Gavin Shan
Quoted 58 lines · Andrew Jones
Quoted 45 lines · Gavin Shan
Quoted 31 lines · Andrew Jones
Quoted 30 lines · Andrew Jones
Quoted 18 lines · Gavin Shan
The empty memory nodes, where no memory resides in, are allowed. For these empty memory nodes, the 'len' of 'reg' property is zero. The NUMA node IDs are still valid and parsed, but memory can be added to them through hotplug afterwards. I finds difficulty to get where it's properly documented.
So lets add note to empty memory nodes in the NUMA binding doc.
Signed-off-by Gavin Shan <[email protected]>--- Documentation/devicetree/bindings/numa.txt | 4 ++++ 1 file changed, 4 insertions(+)Documentation/devicetree/bindings/numa.txt +0
-0Documentation/devicetree/bindings/numa.txt Example: · line 113
Quoted 5 lines
Documentation/devicetree/bindings/numa.txt +3
-0@@ -109,6 +109,10 @@ Example: Dual socket system consists of 2 boards connected through ccn bus and each board having one socket/soc of 8 cpus, memory and pci bus. +Note that empty memory nodes, which no memory resides in, are allowed. +The NUMA node IDs in these empty memory nodes are still valid, but +memory can be added into them through hotplug afterwards.Please change the second sentence to:
The NUMA node IDs in these empty memory nodes are still valid and memory may be added into them through hotplug afterwards.
Quoted 12 lines
Quoted 5 lines
But, this doesn't look like the right place for this paragraph. You're adding the paragraph to the example section, but the example doesn't have any empty memory nodes.
I think the paragraph should be added to section "2 - numa-node-id" and an
Or maybe even create a new section for it.
Quoted 4 lines
example empty memory node should be provided. Also, the commit message talks about the length of 'reg' being zero, which is an important distinction which should also be documented.
Quoted 8 lines
Drew, thanks for your comments. Yeah, it sounds sensible to create a new section for it and an example would be more helpful. Please check if below changes are fine to you. I probably need Randy's review again.
I'm trying to avoid too many revisions for this sort of trivial patch, even though I already had. However, it's time frame for v5.14 and I'm pushing this to be merged during the cycle.
We must revise until we're satisfied... Also, I wouldn't call writing specifications trivial.
[...]
Quoted 7 lines
I'll just rewrite it:
Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
[...]
Quoted 5 lines
You should write how you've selected the dummy addresses for the empty memory nodes, perhaps here in the /* Empty memory node */ comments or above in the paragraph or both.
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt Example: · line 142
Quoted 13 lines
Documentation/devicetree/bindings/numa.txt +13
-0+ memory@0x100000000 { + device_type = "memory"; + reg = <0x1 0x0 0x0 0x0>; + numa-node-id = <2>; + }; + + /* Empty memory node */ + memory@0x180000000 { + device_type = "memory"; + reg = <0x1 0x80000000 0x0 0x0>; + numa-node-id = <3>; + }; +[...]
Thanks, Drew. As 'base-address' is dummy address and invalid. So we would note it as suggestion. With your suggestion integrated, how about something like this?
==============================================================================
4 - Empty memory nodes
==============================================================================Empty memory nodes, which no memory resides in, are allowed. The 'length' field of the 'reg' property is zero, but the 'base-address' is a dummy address and invalid. The 'base-address' could be the summation of highest memory address plus the NUMA node ID. However, the NUMA node IDs and distance maps are still valid and memory may be added into them through hotplug afterwards.
: memory@0 { device_type = "memory"; reg = <0x0 0x0 0x0 0x80000000>; numa-node-id = <0>; }; memory@0x80000000 { device_type = "memory"; reg = <0x0 0x80000000 0x0 0x80000000>; numa-node-id = <1>; }; /* Empty memory node */ memory@0x100000002 { device_type = "memory"; reg = <0x1 0x2 0x0 0x0>; numa-node-id = <2>; }; /* Empty memory node */ memory@0x100000003 { device_type = "memory"; reg = <0x1 0x3 0x0 0x0>; numa-node-id = <3>; };
Quoted 9 lines
Quoted 6 lines
:Thanks,
GavinLooks good to me.
Thanks, Drew. v5 was posted to reflect changes, but I don't include Randy's r-b because too much changes introduced. Hopefully, Randy can take a look on v5 when getting a chance.
Thanks,
Gavin