Commit 6e086302 authored by Srikar Dronamraju's avatar Srikar Dronamraju Committed by Michael Ellerman
Browse files

powerpc/smp: Allocate cpumask only after searching thread group 



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.

Signed-off-by: default avatarSrikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: default avatarGautham R. Shenoy <ego@linux.vnet.ibm.com>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200810071834.92514-9-srikar@linux.vnet.ibm.com
parent f9f130ff

arch/powerpc/kernel/smp.c

+3 −4
Original line number Diff line number Diff line
@@ -790,10 +790,6 @@ 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)) {
@@ -802,6 +798,9 @@ 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);