[PATCH 05/11] powerpc/smp: Dont assume l2-cache to be superset of sibling
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STALE2272d
From: Srikar Dronamraju <hidden>
Date: 2020-07-14 04:45:45
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
Current code assumes that cpumask of cpus sharing a l2-cache mask will always be a superset of cpu_sibling_mask. Lets stop that assumption. Cc: linuxppc-dev <redacted> Cc: Michael Ellerman <redacted> Cc: Nick Piggin <redacted> Cc: Oliver OHalloran <redacted> Cc: Nathan Lynch <redacted> Cc: Michael Neuling <redacted> Cc: Anton Blanchard <redacted> Cc: Gautham R Shenoy <redacted> Cc: Vaidyanathan Srinivasan <redacted> Signed-off-by: Srikar Dronamraju <redacted> --- arch/powerpc/kernel/smp.c | 28 +++++++++++++++------------- 1 file changed, 15 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/kernel/smp.c b/arch/powerpc/kernel/smp.c
index 7d430fc536cc..875f57e41355 100644
--- a/arch/powerpc/kernel/smp.c
+++ b/arch/powerpc/kernel/smp.c@@ -1198,6 +1198,7 @@ static bool update_mask_by_l2(int cpu, struct cpumask *(*mask_fn)(int)) struct device_node *l2_cache, *np; int i; + cpumask_set_cpu(cpu, mask_fn(cpu)); l2_cache = cpu_to_l2cache(cpu); if (!l2_cache) return false;
@@ -1284,29 +1285,30 @@ static void add_cpu_to_masks(int cpu) * add it to it's own thread sibling mask. */ cpumask_set_cpu(cpu, cpu_sibling_mask(cpu)); + cpumask_set_cpu(cpu, cpu_core_mask(cpu)); for (i = first_thread; i < first_thread + threads_per_core; i++) if (cpu_online(i)) set_cpus_related(i, cpu, cpu_sibling_mask); add_cpu_to_smallcore_masks(cpu); - /* - * Copy the thread sibling mask into the cache sibling mask - * and mark any CPUs that share an L2 with this CPU. - */ - for_each_cpu(i, cpu_sibling_mask(cpu)) - set_cpus_related(cpu, i, cpu_l2_cache_mask); update_mask_by_l2(cpu, cpu_l2_cache_mask); - /* - * Copy the cache sibling mask into core sibling mask and mark - * any CPUs on the same chip as this CPU. - */ - for_each_cpu(i, cpu_l2_cache_mask(cpu)) - set_cpus_related(cpu, i, cpu_core_mask); + if (pkg_id == -1) { + struct cpumask *(*mask)(int) = cpu_sibling_mask; + + /* + * Copy the sibling mask into core sibling mask and + * mark any CPUs on the same chip as this CPU. + */ + if (shared_caches) + mask = cpu_l2_cache_mask; + + for_each_cpu(i, mask(cpu)) + set_cpus_related(cpu, i, cpu_core_mask); - if (pkg_id == -1) return; + } for_each_cpu(i, cpu_online_mask) if (get_physical_package_id(i) == pkg_id)
--
2.17.1