diff options
Diffstat (limited to 'kernel/trace/fgraph.c')
| -rw-r--r-- | kernel/trace/fgraph.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index d7d4fb403f6f..41e7a15dcb50 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -1160,19 +1160,14 @@ void fgraph_update_pid_func(void) static int start_graph_tracing(void) { unsigned long **ret_stack_list; - int ret, cpu; + int ret; - ret_stack_list = kmalloc(SHADOW_STACK_SIZE, GFP_KERNEL); + ret_stack_list = kcalloc(FTRACE_RETSTACK_ALLOC_SIZE, + sizeof(*ret_stack_list), GFP_KERNEL); if (!ret_stack_list) return -ENOMEM; - /* The cpu_boot init_task->ret_stack will never be freed */ - for_each_online_cpu(cpu) { - if (!idle_task(cpu)->ret_stack) - ftrace_graph_init_idle_task(idle_task(cpu), cpu); - } - do { ret = alloc_retstack_tasklist(ret_stack_list); } while (ret == -EAGAIN); @@ -1242,14 +1237,34 @@ static void ftrace_graph_disable_direct(bool disable_branch) fgraph_direct_gops = &fgraph_stub; } +/* The cpu_boot init_task->ret_stack will never be freed */ +static int fgraph_cpu_init(unsigned int cpu) +{ + if (!idle_task(cpu)->ret_stack) + ftrace_graph_init_idle_task(idle_task(cpu), cpu); + return 0; +} + int register_ftrace_graph(struct fgraph_ops *gops) { + static bool fgraph_initialized; int command = 0; int ret = 0; int i = -1; mutex_lock(&ftrace_lock); + if (!fgraph_initialized) { + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "fgraph_idle_init", + fgraph_cpu_init, NULL); + if (ret < 0) { + pr_warn("fgraph: Error to init cpu hotplug support\n"); + return ret; + } + fgraph_initialized = true; + ret = 0; + } + if (!fgraph_array[0]) { /* The array must always have real data on it */ for (i = 0; i < FGRAPH_ARRAY_SIZE; i++) |