Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1650696 > unrolled thread

[PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN enabled

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN enabled Michael Bringmann <mwb@linux.vnet.ibm.com> - 2017-05-25 19:40 +0200
    Re: [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN  enabled Tyrel Datwyler <tyreld@linux.vnet.ibm.com> - 2017-05-26 00:10 +0200
    Re: [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN  enabled kbuild test robot <lkp@intel.com> - 2017-05-26 19:30 +0200

#1650696 — [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN enabled

powerpc/numa: Correct the currently broken capability to set the
topology for shared CPUs in LPARs.  At boot time for shared CPU
lpars, the topology for each shared CPU is set to node zero, however,
this is now updated correctly using the Virtual Processor Home Node
(VPHN) capabilities information provided by the pHyp. The VPHN handling
in Linux is disabled, if PRRN handling is present.

Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
---
 arch/powerpc/mm/numa.c                       |   19 ++++++++++++++++++-
 arch/powerpc/platforms/pseries/dlpar.c       |    2 ++
 arch/powerpc/platforms/pseries/hotplug-cpu.c |    3 ++-
 3 files changed, 22 insertions(+), 2 deletions(-)

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 371792e..15c2dd5 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -29,6 +29,7 @@
 #include <linux/seq_file.h>
 #include <linux/uaccess.h>
 #include <linux/slab.h>
+#include <linux/sched.h>
 #include <asm/cputhreads.h>
 #include <asm/sparsemem.h>
 #include <asm/prom.h>
@@ -42,6 +43,8 @@
 #include <asm/vdso.h>
 
 static int numa_enabled = 1;
+static int topology_inited;
+static int topology_update_needed;
 
 static char *cmdline __initdata;
 
@@ -1321,8 +1324,11 @@ int arch_update_cpu_topology(void)
 	struct device *dev;
 	int weight, new_nid, i = 0;
 
-	if (!prrn_enabled && !vphn_enabled)
+	if (!prrn_enabled && !vphn_enabled) {
+		if (!topology_inited)
+			topology_update_needed = 1;
 		return 0;
+	}
 
 	weight = cpumask_weight(&cpu_associativity_changes_mask);
 	if (!weight)
@@ -1361,6 +1367,8 @@ int arch_update_cpu_topology(void)
 			cpumask_andnot(&cpu_associativity_changes_mask,
 					&cpu_associativity_changes_mask,
 					cpu_sibling_mask(cpu));
+			pr_info("Assoc chg gives same node %d for cpu%d\n",
+					new_nid, cpu);
 			cpu = cpu_last_thread_sibling(cpu);
 			continue;
 		}
@@ -1377,6 +1385,9 @@ int arch_update_cpu_topology(void)
 		cpu = cpu_last_thread_sibling(cpu);
 	}
 
+	if (i)
+		updates[i-1].next = NULL;
+
 	pr_debug("Topology update for the following CPUs:\n");
 	if (cpumask_weight(&updated_cpus)) {
 		for (ud = &updates[0]; ud; ud = ud->next) {
@@ -1423,6 +1434,7 @@ int arch_update_cpu_topology(void)
 
 out:
 	kfree(updates);
+	topology_update_needed = 0;
 	return changed;
 }
 
@@ -1600,6 +1612,11 @@ static int topology_update_init(void)
 	if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops))
 		return -ENOMEM;
 
+	topology_inited = 1;
+	if (topology_update_needed)
+		bitmap_fill(cpumask_bits(&cpu_associativity_changes_mask),
+					nr_cpumask_bits);
+
 	return 0;
 }
 device_initcall(topology_update_init);
diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
index bda18d8..5106263 100644
--- a/arch/powerpc/platforms/pseries/dlpar.c
+++ b/arch/powerpc/platforms/pseries/dlpar.c
@@ -592,6 +592,8 @@ static ssize_t dlpar_show(struct class *class, struct class_attribute *attr,
 
 static int __init pseries_dlpar_init(void)
 {
+	arch_update_cpu_topology();
+
 	pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
 					WQ_UNBOUND, 1);
 	return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
index 7bc0e91..b5eff35 100644
--- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
+++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
@@ -619,7 +619,8 @@ static int dlpar_cpu_remove_by_index(u32 drc_index)
 	}
 
 	rc = dlpar_cpu_remove(dn, drc_index);
-	of_node_put(dn);
+	if (rc)
+		of_node_put(dn);
 	return rc;
 }
 

[toc] | [next] | [standalone]

#1650842 — Re: [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN enabled

On 05/25/2017 10:35 AM, Michael Bringmann wrote:
> 
> powerpc/numa: Correct the currently broken capability to set the
> topology for shared CPUs in LPARs.  At boot time for shared CPU
> lpars, the topology for each shared CPU is set to node zero, however,
> this is now updated correctly using the Virtual Processor Home Node
> (VPHN) capabilities information provided by the pHyp. The VPHN handling
> in Linux is disabled, if PRRN handling is present.
> 
> Signed-off-by: Michael Bringmann <mwb@linux.vnet.ibm.com>
> ---
>  arch/powerpc/mm/numa.c                       |   19 ++++++++++++++++++-
>  arch/powerpc/platforms/pseries/dlpar.c       |    2 ++
>  arch/powerpc/platforms/pseries/hotplug-cpu.c |    3 ++-
>  3 files changed, 22 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
> index 371792e..15c2dd5 100644
> --- a/arch/powerpc/mm/numa.c
> +++ b/arch/powerpc/mm/numa.c
> @@ -29,6 +29,7 @@
>  #include <linux/seq_file.h>
>  #include <linux/uaccess.h>
>  #include <linux/slab.h>
> +#include <linux/sched.h>
>  #include <asm/cputhreads.h>
>  #include <asm/sparsemem.h>
>  #include <asm/prom.h>
> @@ -42,6 +43,8 @@
>  #include <asm/vdso.h>
>  
>  static int numa_enabled = 1;
> +static int topology_inited;
> +static int topology_update_needed;
>  
>  static char *cmdline __initdata;
>  
> @@ -1321,8 +1324,11 @@ int arch_update_cpu_topology(void)
>  	struct device *dev;
>  	int weight, new_nid, i = 0;
>  
> -	if (!prrn_enabled && !vphn_enabled)
> +	if (!prrn_enabled && !vphn_enabled) {
> +		if (!topology_inited)
> +			topology_update_needed = 1;
>  		return 0;
> +	}
>  
>  	weight = cpumask_weight(&cpu_associativity_changes_mask);
>  	if (!weight)
> @@ -1361,6 +1367,8 @@ int arch_update_cpu_topology(void)
>  			cpumask_andnot(&cpu_associativity_changes_mask,
>  					&cpu_associativity_changes_mask,
>  					cpu_sibling_mask(cpu));
> +			pr_info("Assoc chg gives same node %d for cpu%d\n",
> +					new_nid, cpu);
>  			cpu = cpu_last_thread_sibling(cpu);
>  			continue;
>  		}
> @@ -1377,6 +1385,9 @@ int arch_update_cpu_topology(void)
>  		cpu = cpu_last_thread_sibling(cpu);
>  	}
>  
> +	if (i)
> +		updates[i-1].next = NULL;
> +
>  	pr_debug("Topology update for the following CPUs:\n");
>  	if (cpumask_weight(&updated_cpus)) {
>  		for (ud = &updates[0]; ud; ud = ud->next) {
> @@ -1423,6 +1434,7 @@ int arch_update_cpu_topology(void)
>  
>  out:
>  	kfree(updates);
> +	topology_update_needed = 0;
>  	return changed;
>  }
>  
> @@ -1600,6 +1612,11 @@ static int topology_update_init(void)
>  	if (!proc_create("powerpc/topology_updates", 0644, NULL, &topology_ops))
>  		return -ENOMEM;
>  
> +	topology_inited = 1;
> +	if (topology_update_needed)
> +		bitmap_fill(cpumask_bits(&cpu_associativity_changes_mask),
> +					nr_cpumask_bits);
> +
>  	return 0;
>  }
>  device_initcall(topology_update_init);
> diff --git a/arch/powerpc/platforms/pseries/dlpar.c b/arch/powerpc/platforms/pseries/dlpar.c
> index bda18d8..5106263 100644
> --- a/arch/powerpc/platforms/pseries/dlpar.c
> +++ b/arch/powerpc/platforms/pseries/dlpar.c
> @@ -592,6 +592,8 @@ static ssize_t dlpar_show(struct class *class, struct class_attribute *attr,
>  
>  static int __init pseries_dlpar_init(void)
>  {
> +	arch_update_cpu_topology();
> +
>  	pseries_hp_wq = alloc_workqueue("pseries hotplug workqueue",
>  					WQ_UNBOUND, 1);
>  	return sysfs_create_file(kernel_kobj, &class_attr_dlpar.attr);
> diff --git a/arch/powerpc/platforms/pseries/hotplug-cpu.c b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> index 7bc0e91..b5eff35 100644
> --- a/arch/powerpc/platforms/pseries/hotplug-cpu.c
> +++ b/arch/powerpc/platforms/pseries/hotplug-cpu.c
> @@ -619,7 +619,8 @@ static int dlpar_cpu_remove_by_index(u32 drc_index)
>  	}
>  
>  	rc = dlpar_cpu_remove(dn, drc_index);
> -	of_node_put(dn);
> +	if (rc)
> +		of_node_put(dn);

This if statement is unnecessary. A reference to dn is grabbed with cpu_drc_index_to_dn()
earlier in the function. So, regardless of whether dlpar_cpu_remove() succeeds or fails we
still need to release the reference we took. I suspect that maybe you threw this in there
to prevent the of_node underflow that was being seen during dlpar remove of cpus. A fix
for that should already be upstream. Either way this hunk doesn't seem to have anything to
do with the rest of this VPHN patch, and should have been a separate patch with its own
change log explaining the reasoning.

-Tyrel

>  	return rc;
>  }
>  
> 

[toc] | [prev] | [next] | [standalone]

#1651534 — Re: [PATCH V2 1/2] powerpc/numa: Update CPU topology when VPHN enabled

[Multipart message — attachments visible in raw view] — view raw

Hi Michael,

[auto build test ERROR on powerpc/next]
[also build test ERROR on v4.12-rc2 next-20170526]
[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/20170526-231219
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: powerpc-powernv_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 

All errors (new ones prefixed by >>):

>> arch/powerpc/mm/numa.c:47:12: error: 'topology_update_needed' defined but not used [-Werror=unused-variable]
    static int topology_update_needed;
               ^~~~~~~~~~~~~~~~~~~~~~
>> arch/powerpc/mm/numa.c:46:12: error: 'topology_inited' defined but not used [-Werror=unused-variable]
    static int topology_inited;
               ^~~~~~~~~~~~~~~
   cc1: all warnings being treated as errors

vim +/topology_update_needed +47 arch/powerpc/mm/numa.c

    40	#include <asm/paca.h>
    41	#include <asm/hvcall.h>
    42	#include <asm/setup.h>
    43	#include <asm/vdso.h>
    44	
    45	static int numa_enabled = 1;
  > 46	static int topology_inited;
  > 47	static int topology_update_needed;
    48	
    49	static char *cmdline __initdata;
    50	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

[toc] | [prev] | [standalone]

Back to top | Article view | linux.kernel

csiph-web