If allocated earlier and the search fails, then cpu_l1_cache_map cpumask
is unnecessarily cleared. However cpu_l1_cache_map can be allocated /
cleared after we search thread group.

Please note CONFIG_CPUMASK_OFFSTACK is not set on Powerpc. Hence cpumask
allocated by zalloc_cpumask_var_node is never freed.

Cc: linuxppc-dev <linuxppc-...@lists.ozlabs.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Michael Ellerman <m...@ellerman.id.au>
Cc: Nicholas Piggin <npig...@gmail.com>
Cc: Anton Blanchard <an...@ozlabs.org>
Cc: Oliver O'Halloran <ooh...@gmail.com>
Cc: Nathan Lynch <nath...@linux.ibm.com>
Cc: Michael Neuling <mi...@neuling.org>
Cc: Gautham R Shenoy <e...@linux.vnet.ibm.com>
Cc: Ingo Molnar <mi...@kernel.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Valentin Schneider <valentin.schnei...@arm.com>
Cc: Jordan Niethe <jniet...@gmail.com>
Cc: Vaidyanathan Srinivasan <sva...@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <e...@linux.vnet.ibm.com>
Signed-off-by: Srikar Dronamraju <sri...@linux.vnet.ibm.com>
---
Changelog v4 ->v5:
        Updated commit msg on why cpumask need not be freed.
                                                (Michael Ellerman)

 arch/powerpc/kernel/smp.c | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 7403fdcf3821..0536ac06876b 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c
@@ -789,10 +789,6 @@ static int init_cpu_l1_cache_map(int cpu)
        if (err)
                goto out;
 
-       zalloc_cpumask_var_node(&per_cpu(cpu_l1_cache_map, cpu),
-                               GFP_KERNEL,
-                               cpu_to_node(cpu));
-
        cpu_group_start = get_cpu_thread_group_start(cpu, &tg);
 
        if (unlikely(cpu_group_start == -1)) {
@@ -801,6 +797,9 @@ static int init_cpu_l1_cache_map(int cpu)
                goto out;
        }
 
+       zalloc_cpumask_var_node(&per_cpu(cpu_l1_cache_map, cpu),
+                               GFP_KERNEL, cpu_to_node(cpu));
+
        for (i = first_thread; i < first_thread + threads_per_core; i++) {
                int i_group_start = get_cpu_thread_group_start(i, &tg);
 
-- 
2.18.2

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