To: [email protected]
From: Michael Bringmann <[email protected]>
To: [email protected]
Cc: Michael Ellerman <[email protected]>
Cc: Michael Bringmann <[email protected]>
Cc: John Allen <[email protected]>
Cc: Nathan Fontenot <[email protected]>
Subject: [PATCH V9 2/2] powerpc/nodes: Ensure enough nodes avail for operations
powerpc/nodes: On systems like PowerPC which allow 'hot-add' of CPU
or memory resources, it may occur that the new resources are to be
inserted into nodes that were not used for these resources at bootup.
In the kernel, any node that is used must be defined and initialized
at boot.
This patch extracts the value of the lowest domain level (number of
allocable resources) from the "rtas" device tree property
"ibm,max-associativity-domains" to use as the maximum number of nodes
to setup as possibly available in the system. This new setting will
override the instruction,
nodes_and(node_possible_map, node_possible_map, node_online_map);
presently seen in the function arch/powerpc/mm/numa.c:initmem_init().
If the property is not present at boot, no operation will be performed
to define or enable additional nodes.
Signed-off-by: Michael Bringmann <[email protected]>
---
arch/powerpc/mm/numa.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 3fd4536..3ae6510 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -893,6 +893,48 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
NODE_DATA(nid)->node_spanned_pages = spanned_pages;
}
+static void __init node_associativity_setup(void)
+{
+ struct device_node *rtas;
+ printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
+
+ rtas = of_find_node_by_path("/rtas");
+ if (rtas) {
+ const __be32 *prop;
+ u32 len, entries, levelval, i;
+ printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
+
+ prop = of_get_property(rtas, "ibm,max-associativity-domains", &len);
+ if (!prop || len < sizeof(unsigned int)) {
+ printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
+ goto endit;
+ }
+
+ entries = of_read_number(prop++, 1);
+
+ if (len < (entries * sizeof(unsigned int))) {
+ printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
+ goto endit;
+ }
+
+ for (i = 0; i < entries; i++)
+ levelval = of_read_number(prop++, 1);
+
+ printk(KERN_INFO "Numa nodes avail: %d (%d) \n", (int) levelval, (int) entries);
+
+ for (i = 0; i < levelval; i++) {
+ if (!node_possible(i)) {
+ setup_node_data(i, 0, 0);
+ node_set(i, node_possible_map);
+ }
+ }
+ }
+
+endit:
+ if (rtas)
+ of_node_put(rtas);
+}
+
void __init initmem_init(void)
{
int nid, cpu;
@@ -912,6 +954,8 @@ void __init initmem_init(void)
*/
nodes_and(node_possible_map, node_possible_map, node_online_map);
+ node_associativity_setup();
+
for_each_online_node(nid) {
unsigned long start_pfn, end_pfn;
Michael Bringmann <[email protected]> writes:
> To: [email protected]
>
> From: Michael Bringmann <[email protected]>
>
> To: [email protected]
> Cc: Michael Ellerman <[email protected]>
> Cc: Michael Bringmann <[email protected]>
> Cc: John Allen <[email protected]>
> Cc: Nathan Fontenot <[email protected]>
> Subject: [PATCH V9 2/2] powerpc/nodes: Ensure enough nodes avail for operations
>
> powerpc/nodes: On systems like PowerPC which allow 'hot-add' of CPU
> or memory resources, it may occur that the new resources are to be
> inserted into nodes that were not used for these resources at bootup.
> In the kernel, any node that is used must be defined and initialized
> at boot.
>
> This patch extracts the value of the lowest domain level (number of
> allocable resources) from the "rtas" device tree property
> "ibm,max-associativity-domains" to use as the maximum number of nodes
> to setup as possibly available in the system. This new setting will
> override the instruction,
Thanks for implementing my suggestion of using "ibm,max-associativity-domains".
However I don't think it's correct to use the lowest domain level.
It's not very clearly specified in PAPR, but I think you need to treat
it like an associativity property and index into based on the
associativity reference points.
You should be able to use min_common_depth as the index.
cheers
On 08/21/2017 04:44 PM, Michael Bringmann wrote:
> To: [email protected]
>
> From: Michael Bringmann <[email protected]>
>
> To: [email protected]
> Cc: Michael Ellerman <[email protected]>
> Cc: Michael Bringmann <[email protected]>
> Cc: John Allen <[email protected]>
> Cc: Nathan Fontenot <[email protected]>
> Subject: [PATCH V9 2/2] powerpc/nodes: Ensure enough nodes avail for operations
>
> powerpc/nodes: On systems like PowerPC which allow 'hot-add' of CPU
> or memory resources, it may occur that the new resources are to be
> inserted into nodes that were not used for these resources at bootup.
> In the kernel, any node that is used must be defined and initialized
> at boot.
>
> This patch extracts the value of the lowest domain level (number of
> allocable resources) from the "rtas" device tree property
> "ibm,max-associativity-domains" to use as the maximum number of nodes
> to setup as possibly available in the system. This new setting will
> override the instruction,
>
> nodes_and(node_possible_map, node_possible_map, node_online_map);
>
> presently seen in the function arch/powerpc/mm/numa.c:initmem_init().
>
> If the property is not present at boot, no operation will be performed
> to define or enable additional nodes.
>
> Signed-off-by: Michael Bringmann <[email protected]>
> ---
> arch/powerpc/mm/numa.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 44 insertions(+)
>
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index 3fd4536..3ae6510 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -893,6 +893,48 @@ static void __init setup_node_data(int nid, u64 start_pfn, u64 end_pfn)
> NODE_DATA(nid)->node_spanned_pages = spanned_pages;
> }
>
> +static void __init node_associativity_setup(void)
> +{
> + struct device_node *rtas;
> + printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
Is there a reson we need to have all these KERN_INFO printk's?
This looks like debug statements that accidentally were left in.
> +
> + rtas = of_find_node_by_path("/rtas");
> + if (rtas) {
> + const __be32 *prop;
> + u32 len, entries, levelval, i;
> + printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
> +
> + prop = of_get_property(rtas, "ibm,max-associativity-domains", &len);
You could put the of_node_put() call here after getting the property and get
rid of all the goto's.
> + if (!prop || len < sizeof(unsigned int)) {
> + printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
> + goto endit;
> + }
> +
> + entries = of_read_number(prop++, 1);
> +
> + if (len < (entries * sizeof(unsigned int))) {
> + printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
> + goto endit;
> + }
> +
> + for (i = 0; i < entries; i++)
> + levelval = of_read_number(prop++, 1);
Couldn't you just read the last enbtry instead of doing a loop reading each
entry until you get to the last one?
-Nathan
> +
> + printk(KERN_INFO "Numa nodes avail: %d (%d) \n", (int) levelval, (int) entries);
> +
> + for (i = 0; i < levelval; i++) {
> + if (!node_possible(i)) {
> + setup_node_data(i, 0, 0);
> + node_set(i, node_possible_map);
> + }
> + }
> + }
> +
> +endit:
> + if (rtas)
> + of_node_put(rtas)> +}
> +
> void __init initmem_init(void)
> {
> int nid, cpu;
> @@ -912,6 +954,8 @@ void __init initmem_init(void)
> */
> nodes_and(node_possible_map, node_possible_map, node_online_map);
>
> + node_associativity_setup();
> +
> for_each_online_node(nid) {
> unsigned long start_pfn, end_pfn;
>
Hi Michael,
[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.13-rc6 next-20170823]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Michael-Bringmann/powerpc-numa-Update-CPU-topology-when-VPHN-enabled/20170823-173526
base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-defconfig (attached as .config)
compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705
reproduce:
wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=powerpc
Note: it may well be a FALSE warning. FWIW you are at least aware of it now.
http://gcc.gnu.org/wiki/Better_Uninitialized_Warnings
All errors (new ones prefixed by >>):
arch/powerpc/mm/numa.c: In function 'initmem_init':
>> arch/powerpc/mm/numa.c:923:3: error: 'levelval' may be used uninitialized in this function [-Werror=maybe-uninitialized]
printk(KERN_INFO "Numa nodes avail: %d (%d) \n", (int) levelval, (int) entries);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
arch/powerpc/mm/numa.c:904:21: note: 'levelval' was declared here
u32 len, entries, levelval, i;
^~~~~~~~
cc1: all warnings being treated as errors
vim +/levelval +923 arch/powerpc/mm/numa.c
895
896 static void __init node_associativity_setup(void)
897 {
898 struct device_node *rtas;
899 printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
900
901 rtas = of_find_node_by_path("/rtas");
902 if (rtas) {
903 const __be32 *prop;
904 u32 len, entries, levelval, i;
905 printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
906
907 prop = of_get_property(rtas, "ibm,max-associativity-domains", &len);
908 if (!prop || len < sizeof(unsigned int)) {
909 printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
910 goto endit;
911 }
912
913 entries = of_read_number(prop++, 1);
914
915 if (len < (entries * sizeof(unsigned int))) {
916 printk(KERN_INFO "%s:%d\n", __FUNCTION__, __LINE__);
917 goto endit;
918 }
919
920 for (i = 0; i < entries; i++)
921 levelval = of_read_number(prop++, 1);
922
> 923 printk(KERN_INFO "Numa nodes avail: %d (%d) \n", (int) levelval, (int) entries);
924
925 for (i = 0; i < levelval; i++) {
926 if (!node_possible(i)) {
927 setup_node_data(i, 0, 0);
928 node_set(i, node_possible_map);
929 }
930 }
931 }
932
933 endit:
934 if (rtas)
935 of_node_put(rtas);
936 }
937
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation