diff options
Diffstat (limited to 'kernel/trace/trace_osnoise.c')
| -rw-r--r-- | kernel/trace/trace_osnoise.c | 50 |
1 files changed, 34 insertions, 16 deletions
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index 66a871553d4a..bbe47781617e 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -253,20 +253,31 @@ static inline struct timerlat_variables *this_cpu_tmr_var(void) } /* + * Protect the interface. + */ +static struct mutex interface_lock; + +/* * tlat_var_reset - Reset the values of the given timerlat_variables */ static inline void tlat_var_reset(void) { struct timerlat_variables *tlat_var; int cpu; + + /* Synchronize with the timerlat interfaces */ + mutex_lock(&interface_lock); /* * So far, all the values are initialized as 0, so * zeroing the structure is perfect. */ for_each_cpu(cpu, cpu_online_mask) { tlat_var = per_cpu_ptr(&per_cpu_timerlat_var, cpu); + if (tlat_var->kthread) + hrtimer_cancel(&tlat_var->timer); memset(tlat_var, 0, sizeof(*tlat_var)); } + mutex_unlock(&interface_lock); } #else /* CONFIG_TIMERLAT_TRACER */ #define tlat_var_reset() do {} while (0) @@ -332,11 +343,6 @@ struct timerlat_sample { #endif /* - * Protect the interface. - */ -static struct mutex interface_lock; - -/* * Tracer data. */ static struct osnoise_data { @@ -1612,6 +1618,7 @@ out: static struct cpumask osnoise_cpumask; static struct cpumask save_cpumask; +static struct cpumask kthread_cpumask; /* * osnoise_sleep - sleep until the next period @@ -1675,6 +1682,7 @@ static inline int osnoise_migration_pending(void) */ mutex_lock(&interface_lock); this_cpu_osn_var()->kthread = NULL; + cpumask_clear_cpu(smp_processor_id(), &kthread_cpumask); mutex_unlock(&interface_lock); return 1; @@ -1945,11 +1953,16 @@ static void stop_kthread(unsigned int cpu) { struct task_struct *kthread; + mutex_lock(&interface_lock); kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread; if (kthread) { - if (test_bit(OSN_WORKLOAD, &osnoise_options)) { + per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + mutex_unlock(&interface_lock); + + if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask) && + !WARN_ON(!test_bit(OSN_WORKLOAD, &osnoise_options))) { kthread_stop(kthread); - } else { + } else if (!WARN_ON(test_bit(OSN_WORKLOAD, &osnoise_options))) { /* * This is a user thread waiting on the timerlat_fd. We need * to close all users, and the best way to guarantee this is @@ -1958,8 +1971,8 @@ static void stop_kthread(unsigned int cpu) kill_pid(kthread->thread_pid, SIGKILL, 1); put_task_struct(kthread); } - per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; } else { + mutex_unlock(&interface_lock); /* if no workload, just return */ if (!test_bit(OSN_WORKLOAD, &osnoise_options)) { /* @@ -1967,7 +1980,6 @@ static void stop_kthread(unsigned int cpu) */ per_cpu(per_cpu_osnoise_var, cpu).sampling = false; barrier(); - return; } } } @@ -1982,12 +1994,8 @@ static void stop_per_cpu_kthreads(void) { int cpu; - cpus_read_lock(); - - for_each_online_cpu(cpu) + for_each_possible_cpu(cpu) stop_kthread(cpu); - - cpus_read_unlock(); } /* @@ -2021,6 +2029,7 @@ static int start_kthread(unsigned int cpu) } per_cpu(per_cpu_osnoise_var, cpu).kthread = kthread; + cpumask_set_cpu(cpu, &kthread_cpumask); return 0; } @@ -2048,8 +2057,16 @@ static int start_per_cpu_kthreads(void) */ cpumask_and(current_mask, cpu_online_mask, &osnoise_cpumask); - for_each_possible_cpu(cpu) + for_each_possible_cpu(cpu) { + if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask)) { + struct task_struct *kthread; + + kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread; + if (!WARN_ON(!kthread)) + kthread_stop(kthread); + } per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL; + } for_each_cpu(cpu, current_mask) { retval = start_kthread(cpu); @@ -2579,7 +2596,8 @@ static int timerlat_fd_release(struct inode *inode, struct file *file) osn_var = per_cpu_ptr(&per_cpu_osnoise_var, cpu); tlat_var = per_cpu_ptr(&per_cpu_timerlat_var, cpu); - hrtimer_cancel(&tlat_var->timer); + if (tlat_var->kthread) + hrtimer_cancel(&tlat_var->timer); memset(tlat_var, 0, sizeof(*tlat_var)); osn_var->sampling = 0; |