* are the same as what exists.
*/
-static atomic_t in_nmi = ATOMIC_INIT(0);
+static atomic_t nmi_running = ATOMIC_INIT(0);
static int mod_code_status; /* holds return value of text write */
static int mod_code_write; /* set when NMI should do the write */
static void *mod_code_ip; /* holds the IP to write to */
void ftrace_nmi_enter(void)
{
- atomic_inc(&in_nmi);
- /* Must have in_nmi seen before reading write flag */
+ atomic_inc(&nmi_running);
+ /* Must have nmi_running seen before reading write flag */
smp_mb();
if (mod_code_write) {
ftrace_mod_code();
void ftrace_nmi_exit(void)
{
- /* Finish all executions before clearing in_nmi */
+ /* Finish all executions before clearing nmi_running */
smp_wmb();
- atomic_dec(&in_nmi);
+ atomic_dec(&nmi_running);
}
static void wait_for_nmi(void)
{
- int waited = 0;
+ if (!atomic_read(&nmi_running))
+ return;
- while (atomic_read(&in_nmi)) {
- waited = 1;
+ do {
cpu_relax();
- }
+ } while (atomic_read(&nmi_running));
- if (waited)
- nmi_wait_count++;
+ nmi_wait_count++;
}
static int
return ftrace_mod_jmp(ip, old_offset, new_offset);
}
-#else /* CONFIG_DYNAMIC_FTRACE */
-
-/*
- * These functions are picked from those used on
- * this page for dynamic ftrace. They have been
- * simplified to ignore all traces in NMI context.
- */
-static atomic_t in_nmi;
-
-void ftrace_nmi_enter(void)
-{
- atomic_inc(&in_nmi);
-}
-
-void ftrace_nmi_exit(void)
-{
- atomic_dec(&in_nmi);
-}
-
#endif /* !CONFIG_DYNAMIC_FTRACE */
/*
&return_to_handler;
/* Nmi's are currently unsupported */
- if (unlikely(atomic_read(&in_nmi)))
+ if (unlikely(in_nmi()))
return;
if (unlikely(atomic_read(¤t->tracing_graph_pause)))
return;
}
- if (unlikely(!__kernel_text_address(old))) {
- ftrace_graph_stop();
- *parent = old;
- WARN_ON(1);
- return;
- }
-
calltime = cpu_clock(raw_smp_processor_id());
if (ftrace_push_return_trace(old, calltime,