9 files changed, 87 insertions, 74 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index 780c8dcf4516..2093a691f1c2 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -96,6 +96,7 @@ obj-$(CONFIG_HAVE_GENERIC_DMA_COHERENT) += dma-coherent.o
 obj-$(CONFIG_FUNCTION_TRACER) += trace/
 obj-$(CONFIG_TRACING) += trace/
 obj-$(CONFIG_X86_DS) += trace/
+obj-$(CONFIG_RING_BUFFER) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
 obj-$(CONFIG_SLOW_WORK) += slow-work.o
 obj-$(CONFIG_PERF_COUNTERS) += perf_counter.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 3718d55fb4c3..f3716bf04df6 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -291,7 +291,9 @@ function_stat_next(void *v, int idx)
         pg = (struct ftrace_profile_page *)((unsigned long)rec & PAGE_MASK);
 
  again:
-        rec++;
+        if (idx != 0)
+                rec++;
+
         if ((void *)rec >= (void *)&pg->records[pg->index]) {
                 pg = pg->next;
                 if (!pg)
@@ -1417,10 +1419,20 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
+
+        if (!(iter->flags & FTRACE_ITER_HASH))
+                *pos = 0;
 
         iter->flags |= FTRACE_ITER_HASH;
 
-        return t_hash_next(m, p, pos);
+        iter->hidx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_hash_next(m, p, &l);
+                if (!p)
+                        break;
+        }
+        return p;
 }
 
 static int t_hash_show(struct seq_file *m, void *v)
@@ -1467,8 +1479,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
                         iter->pg = iter->pg->next;
                         iter->idx = 0;
                         goto retry;
-                } else {
-                        iter->idx = -1;
                 }
         } else {
                 rec = &iter->pg->records[iter->idx++];
@@ -1497,6 +1507,7 @@ static void *t_start(struct seq_file *m, loff_t *pos)
 {
         struct ftrace_iterator *iter = m->private;
         void *p = NULL;
+        loff_t l;
 
         mutex_lock(&ftrace_lock);
         /*
@@ -1508,23 +1519,21 @@ static void *t_start(struct seq_file *m, loff_t *pos)
                 if (*pos > 0)
                         return t_hash_start(m, pos);
                 iter->flags |= FTRACE_ITER_PRINTALL;
-                (*pos)++;
                 return iter;
         }
 
         if (iter->flags & FTRACE_ITER_HASH)
                 return t_hash_start(m, pos);
 
-        if (*pos > 0) {
-                if (iter->idx < 0)
-                        return p;
-                (*pos)--;
-                iter->idx--;
+        iter->pg = ftrace_pages_start;
+        iter->idx = 0;
+        for (l = 0; l <= *pos; ) {
+                p = t_next(m, p, &l);
+                if (!p)
+                        break;
         }
 
-        p = t_next(m, p, pos);
-
-        if (!p)
+        if (!p && iter->flags & FTRACE_ITER_FILTER)
                 return t_hash_start(m, pos);
 
         return p;
@@ -2500,32 +2509,31 @@ int ftrace_graph_count;
 unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
 
 static void *
-g_next(struct seq_file *m, void *v, loff_t *pos)
+__g_next(struct seq_file *m, loff_t *pos)
 {
         unsigned long *array = m->private;
-        int index = *pos;
 
-        (*pos)++;
-
-        if (index >= ftrace_graph_count)
+        if (*pos >= ftrace_graph_count)
                 return NULL;
+        return &array[*pos];
+}
 
-        return &array[index];
+static void *
+g_next(struct seq_file *m, void *v, loff_t *pos)
+{
+        (*pos)++;
+        return __g_next(m, pos);
 }
 
 static void *g_start(struct seq_file *m, loff_t *pos)
 {
-        void *p = NULL;
-
         mutex_lock(&graph_lock);
 
         /* Nothing, tell g_show to print all functions are enabled */
         if (!ftrace_graph_count && !*pos)
                 return (void *)1;
 
-        p = g_next(m, p, pos);
-
-        return p;
+        return __g_next(m, pos);
 }
 
 static void g_stop(struct seq_file *m, void *p)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 04dac2638258..bf27bb7a63e2 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1563,6 +1563,8 @@ rb_reserve_next_event(struct ring_buffer_per_cpu *cpu_buffer,
         return NULL;
 }
 
+#ifdef CONFIG_TRACING
+
 #define TRACE_RECURSIVE_DEPTH 16
 
 static int trace_recursive_lock(void)
@@ -1593,6 +1595,13 @@ static void trace_recursive_unlock(void)
         current->trace_recursion--;
 }
 
+#else
+
+#define trace_recursive_lock()          (0)
+#define trace_recursive_unlock()        do { } while (0)
+
+#endif
+
 static DEFINE_PER_CPU(int, rb_need_resched);
 
 /**
@@ -3104,6 +3113,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
 }
 EXPORT_SYMBOL_GPL(ring_buffer_read_page);
 
+#ifdef CONFIG_TRACING
 static ssize_t
 rb_simple_read(struct file *filp, char __user *ubuf,
                size_t cnt, loff_t *ppos)
@@ -3171,6 +3181,7 @@ static __init int rb_init_debugfs(void)
 }
 
 fs_initcall(rb_init_debugfs);
+#endif
 
 #ifdef CONFIG_HOTPLUG_CPU
 static int rb_cpu_notify(struct notifier_block *self,
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 076fa6f0ee48..3aa0a0dfdfa8 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -284,13 +284,12 @@ void trace_wake_up(void)
 static int __init set_buf_size(char *str)
 {
         unsigned long buf_size;
-        int ret;
 
         if (!str)
                 return 0;
-        ret = strict_strtoul(str, 0, &buf_size);
+        buf_size = memparse(str, &str);
         /* nr_entries can not be zero */
-        if (ret < 0 || buf_size == 0)
+        if (buf_size == 0)
                 return 0;
         trace_buf_size = buf_size;
         return 1;
@@ -2053,25 +2052,23 @@ static int tracing_open(struct inode *inode, struct file *file)
 static void *
 t_next(struct seq_file *m, void *v, loff_t *pos)
 {
-        struct tracer *t = m->private;
+        struct tracer *t = v;
 
         (*pos)++;
 
         if (t)
                 t = t->next;
 
-        m->private = t;
-
         return t;
 }
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
-        struct tracer *t = m->private;
+        struct tracer *t;
         loff_t l = 0;
 
         mutex_lock(&trace_types_lock);
-        for (; t && l < *pos; t = t_next(m, t, &l))
+        for (t = trace_types; t && l < *pos; t = t_next(m, t, &l))
                 ;
 
         return t;
@@ -2107,18 +2104,10 @@ static struct seq_operations show_traces_seq_ops = {
 
 static int show_traces_open(struct inode *inode, struct file *file)
 {
-        int ret;
-
         if (tracing_disabled)
                 return -ENODEV;
 
-        ret = seq_open(file, &show_traces_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-                m->private = trace_types;
-        }
-
-        return ret;
+        return seq_open(file, &show_traces_seq_ops);
 }
 
 static ssize_t
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 6e735d4771f8..3548ae5cc780 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -597,6 +597,7 @@ print_graph_function(struct trace_iterator *iter)
 
 extern struct pid *ftrace_pid_trace;
 
+#ifdef CONFIG_FUNCTION_TRACER
 static inline int ftrace_trace_task(struct task_struct *task)
 {
         if (!ftrace_pid_trace)
@@ -604,6 +605,12 @@ static inline int ftrace_trace_task(struct task_struct *task)
 
         return test_tsk_trace_trace(task);
 }
+#else
+static inline int ftrace_trace_task(struct task_struct *task)
+{
+        return 1;
+}
+#endif
 
 /*
  * trace_iterator_flags is an enumeration that defines bit
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index aa08be69a1b6..53c8fd376a88 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -300,10 +300,18 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *t_start(struct seq_file *m, loff_t *pos)
 {
+        struct ftrace_event_call *call = NULL;
+        loff_t l;
+
         mutex_lock(&event_mutex);
-        if (*pos == 0)
-                m->private = ftrace_events.next;
-        return t_next(m, NULL, pos);
+
+        m->private = ftrace_events.next;
+        for (l = 0; l <= *pos; ) {
+                call = t_next(m, NULL, &l);
+                if (!call)
+                        break;
+        }
+        return call;
 }
 
 static void *
@@ -332,10 +340,18 @@ s_next(struct seq_file *m, void *v, loff_t *pos)
 
 static void *s_start(struct seq_file *m, loff_t *pos)
 {
+        struct ftrace_event_call *call = NULL;
+        loff_t l;
+
         mutex_lock(&event_mutex);
-        if (*pos == 0)
-                m->private = ftrace_events.next;
-        return s_next(m, NULL, pos);
+
+        m->private = ftrace_events.next;
+        for (l = 0; l <= *pos; ) {
+                call = s_next(m, NULL, &l);
+                if (!call)
+                        break;
+        }
+        return call;
 }
 
 static int t_show(struct seq_file *m, void *v)
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 90f134764837..7402144bff21 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -302,8 +302,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
         if (count == -1)
                 seq_printf(m, ":unlimited\n");
         else
-                seq_printf(m, ":count=%ld", count);
-        seq_putc(m, '\n');
+                seq_printf(m, ":count=%ld\n", count);
 
         return 0;
 }
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 9bece9687b62..7b6278110827 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -155,25 +155,19 @@ int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
 EXPORT_SYMBOL_GPL(__ftrace_vprintk);
 
 static void *
-t_next(struct seq_file *m, void *v, loff_t *pos)
+t_start(struct seq_file *m, loff_t *pos)
 {
-        const char **fmt = m->private;
-        const char **next = fmt;
-
-        (*pos)++;
+        const char **fmt = __start___trace_bprintk_fmt + *pos;
 
         if ((unsigned long)fmt >= (unsigned long)__stop___trace_bprintk_fmt)
                 return NULL;
-
-        next = fmt;
-        m->private = ++next;
-
         return fmt;
 }
 
-static void *t_start(struct seq_file *m, loff_t *pos)
+static void *t_next(struct seq_file *m, void * v, loff_t *pos)
 {
-        return t_next(m, NULL, pos);
+        (*pos)++;
+        return t_start(m, pos);
 }
 
 static int t_show(struct seq_file *m, void *v)
@@ -224,15 +218,7 @@ static const struct seq_operations show_format_seq_ops = {
 static int
 ftrace_formats_open(struct inode *inode, struct file *file)
 {
-        int ret;
-
-        ret = seq_open(file, &show_format_seq_ops);
-        if (!ret) {
-                struct seq_file *m = file->private_data;
-
-                m->private = __start___trace_bprintk_fmt;
-        }
-        return ret;
+        return seq_open(file, &show_format_seq_ops);
 }
 
 static const struct file_operations ftrace_formats_fops = {
diff --git a/kernel/trace/trace_stat.c b/kernel/trace/trace_stat.c
index c00643733f4c..e66f5e493342 100644
--- a/kernel/trace/trace_stat.c
+++ b/kernel/trace/trace_stat.c
@@ -199,17 +199,13 @@ static void *stat_seq_start(struct seq_file *s, loff_t *pos)
         mutex_lock(&session->stat_mutex);
 
         /* If we are in the beginning of the file, print the headers */
-        if (!*pos && session->ts->stat_headers) {
-                (*pos)++;
+        if (!*pos && session->ts->stat_headers)
                 return SEQ_START_TOKEN;
-        }
 
         node = rb_first(&session->stat_root);
         for (i = 0; node && i < *pos; i++)
                 node = rb_next(node);
 
-        (*pos)++;
-
         return node;
 }