From mboxrd@z Thu Jan 1 00:00:00 1970 From: sudeep.holla@arm.com (Sudeep Holla) Date: Mon, 18 Jun 2018 14:18:43 +0100 Subject: [PATCH v2 7/7] arm64: topology: re-introduce numa mask check for scheduler MC selection In-Reply-To: <1529327923-17911-1-git-send-email-sudeep.holla@arm.com> References: <1529327923-17911-1-git-send-email-sudeep.holla@arm.com> Message-ID: <1529327923-17911-8-git-send-email-sudeep.holla@arm.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Commit 37c3ec2d810f ("arm64: topology: divorce MC scheduling domain from core_siblings") selected the smallest of LLC, socket siblings, and NUMA node siblings to ensure that the sched domain we build for the MC layer isn't larger than the DIE above it or it's shrunk to the socket or NUMA node if LLC exist acrosis NUMA node/chiplets. Commit acd32e52e4e0 ("arm64: topology: Avoid checking numa mask for scheduler MC selection") reverted the NUMA siblings checks since the CPU topology masks weren't updated on hotplug at that time. This patch re-introduces numa mask check as the CPU and NUMA topology is now updated in hotplug paths. Effectively, this patch does the partial revert of commit acd32e52e4e0. Cc: Catalin Marinas Cc: Will Deacon Signed-off-by: Sudeep Holla --- arch/arm64/kernel/topology.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index e0db80252cfb..01cdc83b1ec7 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -215,8 +215,13 @@ EXPORT_SYMBOL_GPL(cpu_topology); const struct cpumask *cpu_coregroup_mask(int cpu) { - const cpumask_t *core_mask = &cpu_topology[cpu].core_sibling; + const cpumask_t *core_mask = cpumask_of_node(cpu_to_node(cpu)); + /* Find the smaller of NUMA, core or LLC siblings */ + if (cpumask_subset(&cpu_topology[cpu].core_sibling, core_mask)) { + /* not numa in package, lets use the package siblings */ + core_mask = &cpu_topology[cpu].core_sibling; + } if (cpu_topology[cpu].llc_id != -1) { if (cpumask_subset(&cpu_topology[cpu].llc_sibling, core_mask)) core_mask = &cpu_topology[cpu].llc_sibling; -- 2.7.4