#include <linux/clocksource.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
+#include <linux/suspend.h>
#include <linux/debugfs.h>
#include <linux/hardirq.h>
#include <linux/kthread.h>
static int last_ftrace_enabled;
/* set when tracing only a pid */
-int ftrace_pid_trace = -1;
+struct pid *ftrace_pid_trace;
+static struct pid * const ftrace_swapper_pid = &init_struct_pid;
/* Quick disabling of function tracer. */
int function_trace_stop;
else
func = ftrace_list_func;
- if (ftrace_pid_trace >= 0) {
+ if (ftrace_pid_trace) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
if (ftrace_list->next == &ftrace_list_end) {
ftrace_func_t func = ftrace_list->func;
- if (ftrace_pid_trace >= 0) {
+ if (ftrace_pid_trace) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
}
func = ftrace_trace_function;
- if (ftrace_pid_trace >= 0) {
+ if (ftrace_pid_trace) {
set_ftrace_pid_function(func);
func = ftrace_pid_func;
} else {
int type = MATCH_FULL;
unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
unsigned i, match = 0, search_len = 0;
+ int not = 0;
+
+ if (buff[0] == '!') {
+ not = 1;
+ buff++;
+ len--;
+ }
for (i = 0; i < len; i++) {
if (buff[i] == '*') {
matched = 1;
break;
}
- if (matched)
- rec->flags |= flag;
+ if (matched) {
+ if (not)
+ rec->flags &= ~flag;
+ else
+ rec->flags |= flag;
+ }
}
pg = pg->next;
}
struct dyn_ftrace *rec;
struct ftrace_page *pg;
int found = 0;
- int i;
+ int i, j;
if (ftrace_disabled)
return -ENODEV;
kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
if (strcmp(str, buffer) == 0) {
found = 1;
- array[idx] = rec->ip;
+ for (j = 0; j < idx; j++)
+ if (array[j] == rec->ip) {
+ found = 0;
+ break;
+ }
+ if (found)
+ array[idx] = rec->ip;
break;
}
}
char buf[64];
int r;
- if (ftrace_pid_trace >= 0)
- r = sprintf(buf, "%u\n", ftrace_pid_trace);
+ if (ftrace_pid_trace == ftrace_swapper_pid)
+ r = sprintf(buf, "swapper tasks\n");
+ else if (ftrace_pid_trace)
+ r = sprintf(buf, "%u\n", pid_nr(ftrace_pid_trace));
else
r = sprintf(buf, "no pid\n");
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
+static void clear_ftrace_swapper(void)
+{
+ struct task_struct *p;
+ int cpu;
+
+ get_online_cpus();
+ for_each_online_cpu(cpu) {
+ p = idle_task(cpu);
+ clear_tsk_trace_trace(p);
+ }
+ put_online_cpus();
+}
+
+static void set_ftrace_swapper(void)
+{
+ struct task_struct *p;
+ int cpu;
+
+ get_online_cpus();
+ for_each_online_cpu(cpu) {
+ p = idle_task(cpu);
+ set_tsk_trace_trace(p);
+ }
+ put_online_cpus();
+}
+
+static void clear_ftrace_pid(struct pid *pid)
+{
+ struct task_struct *p;
+
+ rcu_read_lock();
+ do_each_pid_task(pid, PIDTYPE_PID, p) {
+ clear_tsk_trace_trace(p);
+ } while_each_pid_task(pid, PIDTYPE_PID, p);
+ rcu_read_unlock();
+
+ put_pid(pid);
+}
+
+static void set_ftrace_pid(struct pid *pid)
+{
+ struct task_struct *p;
+
+ rcu_read_lock();
+ do_each_pid_task(pid, PIDTYPE_PID, p) {
+ set_tsk_trace_trace(p);
+ } while_each_pid_task(pid, PIDTYPE_PID, p);
+ rcu_read_unlock();
+}
+
+static void clear_ftrace_pid_task(struct pid **pid)
+{
+ if (*pid == ftrace_swapper_pid)
+ clear_ftrace_swapper();
+ else
+ clear_ftrace_pid(*pid);
+
+ *pid = NULL;
+}
+
+static void set_ftrace_pid_task(struct pid *pid)
+{
+ if (pid == ftrace_swapper_pid)
+ set_ftrace_swapper();
+ else
+ set_ftrace_pid(pid);
+}
+
static ssize_t
ftrace_pid_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
+ struct pid *pid;
char buf[64];
long val;
int ret;
return ret;
mutex_lock(&ftrace_start_lock);
- if (ret < 0) {
+ if (val < 0) {
/* disable pid tracing */
- if (ftrace_pid_trace < 0)
+ if (!ftrace_pid_trace)
goto out;
- ftrace_pid_trace = -1;
+
+ clear_ftrace_pid_task(&ftrace_pid_trace);
} else {
- struct task_struct *p;
- int found = 0;
+ /* swapper task is special */
+ if (!val) {
+ pid = ftrace_swapper_pid;
+ if (pid == ftrace_pid_trace)
+ goto out;
+ } else {
+ pid = find_get_pid(val);
- if (ftrace_pid_trace == val)
+ if (pid == ftrace_pid_trace) {
+ put_pid(pid);
+ goto out;
+ }
+ }
+
+ if (ftrace_pid_trace)
+ clear_ftrace_pid_task(&ftrace_pid_trace);
+
+ if (!pid)
goto out;
- /*
- * Find the task that matches this pid.
- * TODO: use pid namespaces instead.
- */
- rcu_read_lock();
- for_each_process(p) {
- if (p->pid == val) {
- found = 1;
- set_tsk_trace_trace(p);
- } else if (test_tsk_trace_trace(p))
- clear_tsk_trace_trace(p);
- }
- rcu_read_unlock();
+ ftrace_pid_trace = pid;
- if (found)
- ftrace_pid_trace = val;
- else {
- if (ftrace_pid_trace < 0)
- goto out;
- ftrace_pid_trace = -1;
- }
+ set_ftrace_pid_task(ftrace_pid_trace);
}
/* update the function call */
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static atomic_t ftrace_graph_active;
+static struct notifier_block ftrace_suspend_notifier;
int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace)
{
/* Make sure IRQs see the -1 first: */
barrier();
t->ret_stack = ret_stack_list[start++];
+ atomic_set(&t->tracing_graph_pause, 0);
atomic_set(&t->trace_overrun, 0);
}
} while_each_thread(g, t);
return ret;
}
+/*
+ * Hibernation protection.
+ * The state of the current task is too much unstable during
+ * suspend/restore to disk. We want to protect against that.
+ */
+static int
+ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
+ void *unused)
+{
+ switch (state) {
+ case PM_HIBERNATION_PREPARE:
+ pause_graph_tracing();
+ break;
+
+ case PM_POST_HIBERNATION:
+ unpause_graph_tracing();
+ break;
+ }
+ return NOTIFY_DONE;
+}
+
int register_ftrace_graph(trace_func_graph_ret_t retfunc,
trace_func_graph_ent_t entryfunc)
{
mutex_lock(&ftrace_sysctl_lock);
+ ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
+ register_pm_notifier(&ftrace_suspend_notifier);
+
atomic_inc(&ftrace_graph_active);
ret = start_graph_tracing();
if (ret) {
ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
ftrace_graph_entry = ftrace_graph_entry_stub;
ftrace_shutdown(FTRACE_STOP_FUNC_RET);
+ unregister_pm_notifier(&ftrace_suspend_notifier);
mutex_unlock(&ftrace_sysctl_lock);
}
if (!t->ret_stack)
return;
t->curr_ret_stack = -1;
+ atomic_set(&t->tracing_graph_pause, 0);
atomic_set(&t->trace_overrun, 0);
} else
t->ret_stack = NULL;
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff