diff mbox series

[v5,08/10] powerpc/smp: Allocate cpumask only after searching thread group

Message ID 20200810071834.92514-9-srikar@linux.vnet.ibm.com (mailing list archive)
State Accepted
Commit 6e086302816b2ced602bc99641eb0189c05f018a
Headers show
Series Coregroup support on Powerpc | expand

Checks

Context Check Description
snowpatch_ozlabs/apply_patch warning Failed to apply on branch powerpc/merge (1f788123eabf933e828eab9cf8f018ae18faa38f)
snowpatch_ozlabs/apply_patch warning Failed to apply on branch powerpc/next (a7aaa2f26bfd932a654706b19859e7adf802bee2)
snowpatch_ozlabs/apply_patch warning Failed to apply on branch linus/master (fc80c51fd4b23ec007e88d4c688f2cac1b8648e7)
snowpatch_ozlabs/apply_patch warning Failed to apply on branch powerpc/fixes (bcf876870b95592b52519ed4aafcf9d95999bc9c)
snowpatch_ozlabs/apply_patch warning Failed to apply on branch linux-next (f80535b9aa10b0bbed0fb727247c03e20580db1c)
snowpatch_ozlabs/apply_patch fail Failed to apply to any branch

Commit Message

Srikar Dronamraju Aug. 10, 2020, 7:18 a.m. UTC 
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-dev@lists.ozlabs.org>
Cc: LKML <linux-kernel@vger.kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Oliver O'Halloran <oohall@gmail.com>
Cc: Nathan Lynch <nathanl@linux.ibm.com>
Cc: Michael Neuling <mikey@neuling.org>
Cc: Gautham R Shenoy <ego@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Jordan Niethe <jniethe5@gmail.com>
Cc: Vaidyanathan Srinivasan <svaidy@linux.ibm.com>
Reviewed-by: Gautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: Srikar Dronamraju <srikar@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 mbox series

Patch

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);