static void update_shares(struct sched_domain *sd) { u64 now = cpu_clock(raw_smp_processor_id()); s64 elapsed = now - sd->last_update; /* 为了避免更新过于频繁,这里设定了更新时间阀值 *默认0.25s 更新一次 */ if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) { sd->last_u...
smp_processer_id ()函数(定义在include/linux/smp.h)展开如下。 # define smp_processor_id() __smp_processor_id() #define __smp_processor_id(x) raw_smp_processor_id(x) raw_smp_processor_id与处理器架构相关(下例为ARM64)的实现如下,raw_cpu_ptr获取到 cpu_number 的地址,在解引用得到 cpu i...
static void update_shares(struct sched_domain *sd) { u64 now = cpu_clock(raw_smp_processor_id()); s64 elapsed = now - sd->last_update; if (elapsed >= (s64)(u64)sysctl_sched_shares_ratelimit) {还要再进行一次确认,是不是需要将此调度域中的每个进程组的share值更新 sd->last_update ...
cpuraw_smp_processor_id()vlan_tciskb_vlan_tag_get(skb)vlan_availskb_vlan_tag_present(skb)vlan_tpid skb->vlan_proto randprandom_u32() cBPF在一些平台还在使用,这个代码就和用户空间使用的那种汇编是一样的,但是在X86架构,现在在内核态已经都切换到使用eBPF作为中间语言了。由于用户可以提交cBPF的代码,...
* work->lockdep_map, make a copy and use that here.*/structlockdep_map lockdep_map; lockdep_copy_map(&lockdep_map, &work->lockdep_map);#endif/*ensure we're on the correct CPU*/WARN_ON_ONCE(!(pool->flags & POOL_DISASSOCIATED) &&raw_smp_processor_id()!= pool->cpu);/*...
if (dest_cpu == smp_processor_id()) goto unlock; if (likely(cpu_active(dest_cpu))) { struct migration_arg arg = { p, dest_cpu }; raw_spin_unlock_irqrestore(&p->pi_lock, flags); stop_one_cpu(task_cpu(p), migration_cpu_stop, &arg); ...
notifier->ops->sched_in(notifier, raw_smp_processor_id()); 1. 2. 3. 4. 5. 三、代码演示 创建一个字符设备驱动,名字为my_dev,设备节点的创建将由设备文件系统负责,不需要我么来手动创建,并注册调度抢占通知机制,当被抢占和调度时打印简单的信息。
WARN_ON(!cpumask_test_cpu(raw_smp_processor_id(), hctx->cpumask)); if (unlikely(test_bit(BLK_MQ_S_STOPPED, &hctx->state))) //hardware queue状态判断 return; hctx->run++; /* * Touch any software queue that has pending entries. ...
set_cpu_sibling_map(raw_smp_processor_id()); wmb(); /* * We need to hold call_lock, so there is no inconsistency * between the time smp_call_function() determines number of * IPI recipients, and the time when the determination is made ...
并将正在运行的进程curr保存到prev中 */cpu=smp_processor_id();rq=cpu_rq(cpu);prev=rq->curr;/* * do_exit() calls schedule() with preemption disabled as an exception; * however we must fix that up, otherwise the next task will see an ...