hulk inclusion category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I9NR7Q CVE: NA
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We need to make sure that the housekeeper, one of the housekeeping CPUs, is online, as describe in the below Link. We add this check after secondary CPUs online is finished.
Link: https://lore.kernel.org/all/20190504002733.GB19076@lenoir/ Signed-off-by: Xiongfeng Wang wangxiongfeng2@huawei.com --- include/linux/sched/isolation.h | 2 ++ kernel/sched/isolation.c | 13 +++++++++++++ kernel/smp.c | 4 ++++ 3 files changed, 19 insertions(+)
diff --git a/include/linux/sched/isolation.h b/include/linux/sched/isolation.h index 2f93081ad7a0..f665bc8ff633 100644 --- a/include/linux/sched/isolation.h +++ b/include/linux/sched/isolation.h @@ -26,6 +26,7 @@ extern bool housekeeping_enabled(enum hk_flags flags); extern void housekeeping_affine(struct task_struct *t, enum hk_flags flags); extern bool housekeeping_test_cpu(int cpu, enum hk_flags flags); extern void __init housekeeping_init(void); +extern void check_housekeeping_cpu_online(void);
#else
@@ -48,6 +49,7 @@ static inline bool housekeeping_enabled(enum hk_flags flags) static inline void housekeeping_affine(struct task_struct *t, enum hk_flags flags) { } static inline void housekeeping_init(void) { } +static inline void check_housekeeping_cpu_online(void) { } #endif /* CONFIG_CPU_ISOLATION */
static inline bool housekeeping_cpu(int cpu, enum hk_flags flags) diff --git a/kernel/sched/isolation.c b/kernel/sched/isolation.c index 68cd58539e40..237b24bbbcc4 100644 --- a/kernel/sched/isolation.c +++ b/kernel/sched/isolation.c @@ -218,3 +218,16 @@ static int __init enhanced_isolcpus_setup(char *str) return 0; } __setup("enhanced_isolcpus", enhanced_isolcpus_setup); + +void check_housekeeping_cpu_online(void) +{ + if (!support_cpu0_nohz_full) + return; + if (!housekeeping_flags) + return; + if (!cpumask_intersects(housekeeping_mask, cpu_online_mask)) { + pr_err("All the housekeeping CPUs are offline, please modify the kernel parameter !\n"); + /* BUG() here, otherwise we may BUG() in sched_init_smp(). */ + BUG(); + } +} diff --git a/kernel/smp.c b/kernel/smp.c index 4b13a7ef6a31..d9ba6935f83f 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -20,6 +20,7 @@ #include <linux/cpu.h> #include <linux/sched.h> #include <linux/sched/idle.h> +#include <linux/sched/isolation.h> #include <linux/hypervisor.h> #include <linux/sched/clock.h> #include <linux/nmi.h> @@ -884,6 +885,9 @@ void __init smp_init(void)
/* Any cleanup work */ smp_cpus_done(setup_max_cpus); + + /* Check whether there exists a housekeeping CPU online */ + check_housekeeping_cpu_online(); }
/*