From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hao Xu Subject: [PATCH 1/2] cpuset: add a helper to check if cpu in cpuset of current task Date: Wed, 1 Sep 2021 20:43:21 +0800 Message-ID: <20210901124322.164238-2-haoxu@linux.alibaba.com> References: <20210901124322.164238-1-haoxu@linux.alibaba.com> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20210901124322.164238-1-haoxu-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org> List-ID: Content-Type: text/plain; charset="us-ascii" To: Jens Axboe , Zefan Li , Tejun Heo , Johannes Weiner , Pavel Begunkov Cc: io-uring-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Joseph Qi Check if a cpu is in the cpuset of current task, not guaranteed that cpu is online. Signed-off-by: Hao Xu --- include/linux/cpuset.h | 7 +++++++ kernel/cgroup/cpuset.c | 11 +++++++++++ 2 files changed, 18 insertions(+) diff --git a/include/linux/cpuset.h b/include/linux/cpuset.h index 04c20de66afc..fad77c91bc1f 100644 --- a/include/linux/cpuset.h +++ b/include/linux/cpuset.h @@ -116,6 +116,8 @@ static inline int cpuset_do_slab_mem_spread(void) extern bool current_cpuset_is_being_rebound(void); +extern bool test_cpu_in_current_cpuset(int cpu); + extern void rebuild_sched_domains(void); extern void cpuset_print_current_mems_allowed(void); @@ -257,6 +259,11 @@ static inline bool current_cpuset_is_being_rebound(void) return false; } +static inline bool test_cpu_in_current_cpuset(int cpu) +{ + return false; +} + static inline void rebuild_sched_domains(void) { partition_sched_domains(1, NULL, NULL); diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index adb5190c4429..a63c27e9430e 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -1849,6 +1849,17 @@ bool current_cpuset_is_being_rebound(void) return ret; } +bool test_cpu_in_current_cpuset(int cpu) +{ + bool ret; + + rcu_read_lock(); + ret = cpumask_test_cpu(cpu, task_cs(current)->effective_cpus); + rcu_read_unlock(); + + return ret; +} + static int update_relax_domain_level(struct cpuset *cs, s64 val) { #ifdef CONFIG_SMP -- 2.24.4