Linux：NFS 无法挂载异常案例 (1)
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
2) | do_mount() {
2) | user_path_at_empty() {
2) | getname_flags() {
2) | kmem_cache_alloc() {
2) 4.667 us | should_failslab();
2) + 14.875 us | }
2) + 23.917 us | }
2) | filename_lookup() {
2) 4.375 us | set_nameidata();
2) | path_lookupat() {
2) | path_init() {
2) 5.250 us | __rcu_read_lock();
2) | nd_jump_root() {
2) 4.375 us | set_root();
2) + 14.000 us | }
2) + 32.667 us | }
2) | link_path_walk() {
2) | inode_permission() {
2) 4.375 us | generic_permission();
2) + 14.000 us | }
2) | walk_component() {
2) | lookup_fast() {
2) 5.833 us | __d_lookup_rcu();
2) + 14.291 us | }
2) 4.667 us | step_into();
2) + 31.791 us | }
2) | inode_permission() {
2) 4.083 us | generic_permission();
2) + 14.292 us | }
2) + 77.875 us | }
2) | walk_component() {
2) | lookup_fast() {
2) 5.833 us | __d_lookup_rcu();
2) + 14.292 us | }
2) 4.375 us | step_into();
2) + 35.583 us | }
2) | complete_walk() {
2) | try_to_unlazy() {
2) 4.375 us | legitimize_links();
2) | __legitimize_path() {
2) 5.834 us | __legitimize_mnt();
2) + 14.584 us | }
2) 4.375 us | legitimize_root();
2) 4.083 us | __rcu_read_unlock();
2) + 52.500 us | }
2) 4.083 us | success_walk_trace();
2) + 71.750 us | }
2) | terminate_walk() {
2) 4.084 us | drop_links();
2) | path_put() {
2) 4.375 us | dput();
2) 4.375 us | mntput();
2) + 23.625 us | }
2) + 40.834 us | }
2) ! 285.833 us | }
2) 4.375 us | restore_nameidata();
2) | putname() {
2) 4.958 us | kmem_cache_free();
2) + 14.875 us | }
2) ! 331.041 us | }
2) ! 368.084 us | }
2) | path_mount() {
2) | ns_capable() {
2) | ns_capable_common() {
2) 4.375 us | cap_capable();
2) + 13.125 us | }
2) + 23.333 us | }
2) | get_fs_type() {
2) | __get_fs_type() {
2) | _raw_read_lock() {
2) 4.375 us | preempt_count_add();
2) + 14.583 us | }
2) + 18.083 us | find_filesystem();
2) 4.958 us | try_module_get();
2) | _raw_read_unlock() {
2) 4.375 us | preempt_count_sub();
2) + 13.125 us | }
2) + 73.208 us | }
2) + 84.292 us | }
2) | fs_context_for_mount() {
2) | alloc_fs_context() {
2) | kmem_cache_alloc_trace() {
2) 4.084 us | should_failslab();
2) + 15.167 us | }
2) | get_filesystem() {
2) ==========> |
2) | gic_handle_irq() {
2) | __handle_domain_irq() {
2) 1.750 us | irq_find_mapping();
2) 5.833 us | irq_to_desc();
2) | irq_enter() {
2) | irq_enter_rcu() {
2) 1.750 us | preempt_count_add();
2) 5.250 us | }
2) 8.167 us | }
2) | handle_percpu_devid_irq() {
2) | arch_timer_handler_phys() {
2) | hrtimer_interrupt() {
2) | _raw_spin_lock_irqsave() {
2) 1.750 us | preempt_count_add();
2) 4.666 us | }
2) | ktime_get_update_offsets_now() {
2) 1.459 us | arch_counter_read();
2) 4.958 us | }
2) | __hrtimer_run_queues() {
2) 1.750 us | __remove_hrtimer();
2) | _raw_spin_unlock_irqrestore() {
2) 1.459 us | preempt_count_sub();
2) 4.667 us | }
2) | tick_sched_timer() {
2) | ktime_get() {
2) 1.459 us | arch_counter_read();
2) 4.667 us | }
2) | tick_sched_do_timer() {
2) | tick_do_update_jiffies64() {
2) | _raw_spin_lock() {
2) 1.459 us | preempt_count_add();
2) 4.667 us | }
2) | do_timer() {
2) 2.042 us | calc_global_load();
2) 4.667 us | }
2) | _raw_spin_unlock() {
2) 1.458 us | preempt_count_sub();
2) 4.666 us | }
2) | update_wall_time() {
2) | timekeeping_advance() {
2) | _raw_spin_lock_irqsave() {
2) 1.750 us | preempt_count_add();
2) 4.667 us | }
2) 1.750 us | arch_counter_read();
2) 1.458 us | ntp_tick_length();
2) 1.458 us | ntp_tick_length();
2) | timekeeping_update() {
2) 1.750 us | ntp_get_next_leap();
2) 1.750 us | update_vsyscall();
2) | raw_notifier_call_chain() {
2) 1.750 us | notifier_call_chain();
2) 4.667 us | }
2) 1.750 us | update_fast_timekeeper();
2) 1.459 us | update_fast_timekeeper();
2) + 21.000 us | }
2) | _raw_spin_unlock_irqrestore() {
2) 1.458 us | preempt_count_sub();
2) 4.666 us | }
2) + 46.083 us | }
2) + 49.000 us | }
2) + 70.875 us | }
2) + 73.792 us | }
2) | tick_sched_handle() {
2) | update_process_times() {
2) | account_process_tick() {
2) | account_system_time() {
2) | account_system_index_time() {
2) 1.458 us | __rcu_read_lock();
2) 1.750 us | __rcu_read_unlock();
2) | cpufreq_acct_update_power() {
2) | _raw_spin_lock_irqsave() {
2) 1.459 us | preempt_count_add();
2) 4.667 us | }
2) | _raw_spin_unlock_irqrestore() {
2) 1.459 us | preempt_count_sub();
2) 4.375 us | }
2) + 14.292 us | }
2) + 24.500 us | }
2) + 27.417 us | }
2) + 30.625 us | }
2) | run_local_timers() {
2) 1.750 us | hrtimer_run_queues();
2) 4.958 us | }
2) | rcu_sched_clock_irq() {
2) 1.750 us | rcu_is_cpu_rrupt_from_idle();
2) 1.458 us | rcu_preempt_need_deferred_qs();
2) 1.459 us | rcu_qs();
2) 2.042 us | rcu_stall_kick_kthreads();
2) 1.750 us | rcu_is_cpu_rrupt_from_idle();
2) 3.208 us | rcu_segcblist_ready_cbs();
2) + 23.333 us | }
2) | scheduler_tick() {
2) 1.750 us | topology_scale_freq_tick();
2) | _raw_spin_lock() {
2) 1.750 us | preempt_count_add();
2) 4.666 us | }
2) 1.750 us | update_rq_clock();
2) | update_thermal_load_avg() {
2) 1.750 us | decay_load();
2) 1.750 us | decay_load();
2) 1.458 us | decay_load();
2) + 11.083 us | }
2) | task_tick_fair() {
2) | update_curr() {
2) 1.750 us | update_min_vruntime();
2) 1.459 us | __rcu_read_lock();
2) 1.458 us | __rcu_read_unlock();
2) + 10.792 us | }
2) | __update_load_avg_se() {
2) 1.458 us | decay_load();
2) 1.750 us | decay_load();
2) 1.750 us | decay_load();
2) | __accumulate_pelt_segments() {
2) 1.750 us | decay_load();
2) 1.459 us | decay_load();
2) 7.583 us | }
2) + 20.125 us | }
2) | __update_load_avg_cfs_rq(<