From b6ac72d9ea7698fa36b5a56c98ad40fa5693c96f Mon Sep 17 00:00:00 2001 From: James Morse Date: Mon, 24 Jun 2019 18:36:56 +0100 Subject: [PATCH] drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT commit 83b44fe343b5abfcb1b2261289bd0cfcfcfd60a8 upstream. The cacheinfo structures are alloced/freed by cpu online/offline callbacks. Originally these were only used by sysfs to expose the cache topology to user space. Without any in-kernel dependencies CPUHP_AP_ONLINE_DYN was an appropriate choice. resctrl has started using these structures to identify CPUs that share a cache. It updates its 'domain' structures from cpu online/offline callbacks. These depend on the cacheinfo structures (resctrl_online_cpu()->domain_add_cpu()->get_cache_id()-> get_cpu_cacheinfo()). These also run as CPUHP_AP_ONLINE_DYN. Now that there is an in-kernel dependency, move the cacheinfo work earlier so we know its done before resctrl's CPUHP_AP_ONLINE_DYN work runs. Fixes: 2264d9c74dda1 ("x86/intel_rdt: Build structures for each resource based on cache topology") Cc: Cc: Fenghua Yu Cc: Reinette Chatre Signed-off-by: James Morse Link: https://lore.kernel.org/r/20190624173656.202407-1-james.morse@arm.com Signed-off-by: Greg Kroah-Hartman --- drivers/base/cacheinfo.c | 3 ++- include/linux/cpuhotplug.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c index 07532d83be0b..e405ea3ca8d8 100644 --- a/drivers/base/cacheinfo.c +++ b/drivers/base/cacheinfo.c @@ -669,7 +669,8 @@ static int cacheinfo_cpu_pre_down(unsigned int cpu) static int __init cacheinfo_sysfs_init(void) { - return cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "base/cacheinfo:online", + return cpuhp_setup_state(CPUHP_AP_BASE_CACHEINFO_ONLINE, + "base/cacheinfo:online", cacheinfo_cpu_online, cacheinfo_cpu_pre_down); } device_initcall(cacheinfo_sysfs_init); diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 6376e2dcb0b7..0c78ad0cc515 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -163,6 +163,7 @@ enum cpuhp_state { CPUHP_AP_PERF_POWERPC_THREAD_IMC_ONLINE, CPUHP_AP_WORKQUEUE_ONLINE, CPUHP_AP_RCUTREE_ONLINE, + CPUHP_AP_BASE_CACHEINFO_ONLINE, CPUHP_AP_ONLINE_DYN, CPUHP_AP_ONLINE_DYN_END = CPUHP_AP_ONLINE_DYN + 30, CPUHP_AP_X86_HPET_ONLINE, -- 2.20.1