1 files changed, 61 insertions, 7 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 7847806eefef..1752a63f37c0 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -29,6 +29,8 @@
 #include <linux/list.h>
 #include <linux/hash.h>
 
+#include <trace/sched.h>
+
 #include <asm/ftrace.h>
 
 #include "trace.h"
@@ -339,7 +341,7 @@ static inline int record_frozen(struct dyn_ftrace *rec)
 
 static void ftrace_free_rec(struct dyn_ftrace *rec)
 {
-        rec->ip = (unsigned long)ftrace_free_records;
+        rec->freelist = ftrace_free_records;
         ftrace_free_records = rec;
         rec->flags |= FTRACE_FL_FREE;
 }
@@ -356,9 +358,14 @@ void ftrace_release(void *start, unsigned long size)
 
         mutex_lock(&ftrace_lock);
         do_for_each_ftrace_rec(pg, rec) {
-                if ((rec->ip >= s) && (rec->ip < e) &&
-                    !(rec->flags & FTRACE_FL_FREE))
+                if ((rec->ip >= s) && (rec->ip < e)) {
+                        /*
+                         * rec->ip is changed in ftrace_free_rec()
+                         * It should not between s and e if record was freed.
+                         */
+                        FTRACE_WARN_ON(rec->flags & FTRACE_FL_FREE);
                         ftrace_free_rec(rec);
+                }
         } while_for_each_ftrace_rec();
         mutex_unlock(&ftrace_lock);
 }
@@ -377,7 +384,7 @@ static struct dyn_ftrace *ftrace_alloc_dyn_node(unsigned long ip)
                         return NULL;
                 }
 
-                ftrace_free_records = (void *)rec->ip;
+                ftrace_free_records = rec->freelist;
                 memset(rec, 0, sizeof(*rec));
                 return rec;
         }
@@ -409,7 +416,7 @@ ftrace_record_ip(unsigned long ip)
                 return NULL;
 
         rec->ip = ip;
-        rec->flags = (unsigned long)ftrace_new_addrs;
+        rec->newlist = ftrace_new_addrs;
         ftrace_new_addrs = rec;
 
         return rec;
@@ -729,7 +736,7 @@ static int ftrace_update_code(struct module *mod)
                         return -1;
 
                 p = ftrace_new_addrs;
-                ftrace_new_addrs = (struct dyn_ftrace *)p->flags;
+                ftrace_new_addrs = p->newlist;
                 p->flags = 0L;
 
                 /* convert record (i.e, patch mcount-call with NOP) */
@@ -2262,7 +2269,7 @@ ftrace_pid_read(struct file *file, char __user *ubuf,
         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));
+                r = sprintf(buf, "%u\n", pid_vnr(ftrace_pid_trace));
         else
                 r = sprintf(buf, "no pid\n");
 
@@ -2590,6 +2597,38 @@ free:
         return ret;
 }
 
+static void
+ftrace_graph_probe_sched_switch(struct rq *__rq, struct task_struct *prev,
+                                struct task_struct *next)
+{
+        unsigned long long timestamp;
+        int index;
+
+        /*
+         * Does the user want to count the time a function was asleep.
+         * If so, do not update the time stamps.
+         */
+        if (trace_flags & TRACE_ITER_SLEEP_TIME)
+                return;
+
+        timestamp = trace_clock_local();
+
+        prev->ftrace_timestamp = timestamp;
+
+        /* only process tasks that we timestamped */
+        if (!next->ftrace_timestamp)
+                return;
+
+        /*
+         * Update all the counters in next to make up for the
+         * time next was sleeping.
+         */
+        timestamp -= next->ftrace_timestamp;
+
+        for (index = next->curr_ret_stack; index >= 0; index--)
+                next->ret_stack[index].calltime += timestamp;
+}
+
 /* Allocate a return stack for each task */
 static int start_graph_tracing(void)
 {
@@ -2611,6 +2650,13 @@ static int start_graph_tracing(void)
                 ret = alloc_retstack_tasklist(ret_stack_list);
         } while (ret == -EAGAIN);
 
+        if (!ret) {
+                ret = register_trace_sched_switch(ftrace_graph_probe_sched_switch);
+                if (ret)
+                        pr_info("ftrace_graph: Couldn't activate tracepoint"
+                                " probe to kernel_sched_switch\n");
+        }
+
         kfree(ret_stack_list);
         return ret;
 }
@@ -2643,6 +2689,12 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
 
         mutex_lock(&ftrace_lock);
 
+        /* we currently allow only one tracer registered at a time */
+        if (atomic_read(&ftrace_graph_active)) {
+                ret = -EBUSY;
+                goto out;
+        }
+
         ftrace_suspend_notifier.notifier_call = ftrace_suspend_notifier_call;
         register_pm_notifier(&ftrace_suspend_notifier);
 
@@ -2668,6 +2720,7 @@ void unregister_ftrace_graph(void)
         mutex_lock(&ftrace_lock);
 
         atomic_dec(&ftrace_graph_active);
+        unregister_trace_sched_switch(ftrace_graph_probe_sched_switch);
         ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
         ftrace_graph_entry = ftrace_graph_entry_stub;
         ftrace_shutdown(FTRACE_STOP_FUNC_RET);
@@ -2688,6 +2741,7 @@ void ftrace_graph_init_task(struct task_struct *t)
                 t->curr_ret_stack = -1;
                 atomic_set(&t->tracing_graph_pause, 0);
                 atomic_set(&t->trace_overrun, 0);
+                t->ftrace_timestamp = 0;
         } else
                 t->ret_stack = NULL;
 }