x86, numa: Fix cpu nodemasks for NUMA emulation and CONFIG_DEBUG_PER_CPU_MAPS

The cpu<->node mappings under CONFIG_DEBUG_PER_CPU_MAPS=y
when NUMA emulation is enabled is currently broken because it does
not iterate through every emulated node and bind cpus that have
affinity to it.

NUMA emulation should bind each cpu to every local node to
accurately represent the true NUMA topology of the underlying
machine.

debug_cpumask_set_cpu() needs to be fixed at the same time so
that the debugging information that it emits shows the new
cpumask of the node being assigned when the cpu is being added
or removed.

It can now take responsibility of setting or clearing the cpu
itself to remove the need for duplicate code.

Also change its last parameter, "enable", to have the correct bool
type since it can only be true or false.

 -v2: Fix the return statements, by Kosaki Motohiro

Acked-and-Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: Andreas Herrmann <herrmann.der.user@googlemail.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.00.1104201918470.12634@chino.kir.corp.google.com
Signed-off-by: Ingo Molnar <mingo@elte.hu>

diff --git a/arch/x86/include/asm/numa.h b/arch/x86/include/asm/numa.h
index 3d4dab43c99469b6d917f0ba4f4bebd7cdc25bb6..a50fc9f493b3d68a4750a085d48d98b4e4ba72ea 100644 (file)
--- a/arch/x86/include/asm/numa.h
+++ b/arch/x86/include/asm/numa.h
@@ -51,7 +51,7 @@ static inline void numa_remove_cpu(int cpu)           { }
 #endif /* CONFIG_NUMA */
 
 #ifdef CONFIG_DEBUG_PER_CPU_MAPS
-struct cpumask __cpuinit *debug_cpumask_set_cpu(int cpu, int enable);
+void debug_cpumask_set_cpu(int cpu, int node, bool enable);
 #endif
 
 #endif /* _ASM_X86_NUMA_H */

diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c
index 9559d360fde79b8373d042fb48e24c98b836684d..745258dfc4dc1cc93afdd96e6944aac4d9c4a0ec 100644 (file)
--- a/arch/x86/mm/numa.c
+++ b/arch/x86/mm/numa.c
@@ -213,53 +213,48 @@ int early_cpu_to_node(int cpu)
        return per_cpu(x86_cpu_to_node_map, cpu);
 }
 
-struct cpumask __cpuinit *debug_cpumask_set_cpu(int cpu, int enable)
+void debug_cpumask_set_cpu(int cpu, int node, bool enable)
 {
-       int node = early_cpu_to_node(cpu);
        struct cpumask *mask;
        char buf[64];
 
        if (node == NUMA_NO_NODE) {
                /* early_cpu_to_node() already emits a warning and trace */
-               return NULL;
+               return;
        }
        mask = node_to_cpumask_map[node];
        if (!mask) {
                pr_err("node_to_cpumask_map[%i] NULL\n", node);
                dump_stack();
-               return NULL;
+               return;
        }
 
+       if (enable)
+               cpumask_set_cpu(cpu, mask);
+       else
+               cpumask_clear_cpu(cpu, mask);
+
        cpulist_scnprintf(buf, sizeof(buf), mask);
        printk(KERN_DEBUG "%s cpu %d node %d: mask now %s\n",
                enable ? "numa_add_cpu" : "numa_remove_cpu",
                cpu, node, buf);
-       return mask;
+       return;
 }
 
 # ifndef CONFIG_NUMA_EMU
-static void __cpuinit numa_set_cpumask(int cpu, int enable)
+static void __cpuinit numa_set_cpumask(int cpu, bool enable)
 {
-       struct cpumask *mask;
-
-       mask = debug_cpumask_set_cpu(cpu, enable);
-       if (!mask)
-               return;
-
-       if (enable)
-               cpumask_set_cpu(cpu, mask);
-       else
-               cpumask_clear_cpu(cpu, mask);
+       debug_cpumask_set_cpu(cpu, early_cpu_to_node(cpu), enable);
 }
 
 void __cpuinit numa_add_cpu(int cpu)
 {
-       numa_set_cpumask(cpu, 1);
+       numa_set_cpumask(cpu, true);
 }
 
 void __cpuinit numa_remove_cpu(int cpu)
 {
-       numa_set_cpumask(cpu, 0);
+       numa_set_cpumask(cpu, false);
 }
 # endif        /* !CONFIG_NUMA_EMU */
 

diff --git a/arch/x86/mm/numa_emulation.c b/arch/x86/mm/numa_emulation.c
index ad091e4cff17f01a598c7a2c1b3a5a541e9d96a1..de84cc140379ea0b3688d4815577b8c7548e8a44 100644 (file)
--- a/arch/x86/mm/numa_emulation.c
+++ b/arch/x86/mm/numa_emulation.c
@@ -454,10 +454,9 @@ void __cpuinit numa_remove_cpu(int cpu)
                cpumask_clear_cpu(cpu, node_to_cpumask_map[i]);
 }
 #else  /* !CONFIG_DEBUG_PER_CPU_MAPS */
-static void __cpuinit numa_set_cpumask(int cpu, int enable)
+static void __cpuinit numa_set_cpumask(int cpu, bool enable)
 {
-       struct cpumask *mask;
-       int nid, physnid, i;
+       int nid, physnid;
 
        nid = early_cpu_to_node(cpu);
        if (nid == NUMA_NO_NODE) {
@@ -467,28 +466,21 @@ static void __cpuinit numa_set_cpumask(int cpu, int enable)
 
        physnid = emu_nid_to_phys[nid];
 
-       for_each_online_node(i) {
+       for_each_online_node(nid) {
                if (emu_nid_to_phys[nid] != physnid)
                        continue;
 
-               mask = debug_cpumask_set_cpu(cpu, enable);
-               if (!mask)
-                       return;
-
-               if (enable)
-                       cpumask_set_cpu(cpu, mask);
-               else
-                       cpumask_clear_cpu(cpu, mask);
+               debug_cpumask_set_cpu(cpu, nid, enable);
        }
 }
 
 void __cpuinit numa_add_cpu(int cpu)
 {
-       numa_set_cpumask(cpu, 1);
+       numa_set_cpumask(cpu, true);
 }
 
 void __cpuinit numa_remove_cpu(int cpu)
 {
-       numa_set_cpumask(cpu, 0);
+       numa_set_cpumask(cpu, false);
 }
 #endif /* !CONFIG_DEBUG_PER_CPU_MAPS */