23 files changed, 582 insertions, 164 deletions

diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index d36f68b08acc..c674ee8f7fca 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -44,6 +44,10 @@ const char *ftrace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
 const char *ftrace_print_hex_seq(struct trace_seq *p,
                                  const unsigned char *buf, int len);
 
+const char *ftrace_print_array_seq(struct trace_seq *p,
+                                   const void *buf, int buf_len,
+                                   size_t el_size);
+
 struct trace_iterator;
 struct trace_event;
 
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index 27609dfcce25..41bf65f04dd9 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -263,6 +263,14 @@
 #undef __print_hex
 #define __print_hex(buf, buf_len) ftrace_print_hex_seq(p, buf, buf_len)
 
+#undef __print_array
+#define __print_array(array, count, el_size)                            \
+        ({                                                              \
+                BUILD_BUG_ON(el_size != 1 && el_size != 2 &&            \
+                             el_size != 4 && el_size != 8);             \
+                ftrace_print_array_seq(p, array, count, el_size);       \
+        })
+
 #undef DECLARE_EVENT_CLASS
 #define DECLARE_EVENT_CLASS(call, proto, args, tstruct, assign, print)  \
 static notrace enum print_line_t                                        \
@@ -674,6 +682,7 @@ static inline void ftrace_test_probe_##call(void)			\
 #undef __get_dynamic_array_len
 #undef __get_str
 #undef __get_bitmask
+#undef __print_array
 
 #undef TP_printk
 #define TP_printk(fmt, args...) "\"" fmt "\", "  __stringify(args)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 224e768bdc73..45e5cb143d17 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5456,7 +5456,7 @@ static __init int ftrace_init_debugfs(void)
         struct dentry *d_tracer;
 
         d_tracer = tracing_init_dentry();
-        if (!d_tracer)
+        if (IS_ERR(d_tracer))
                 return 0;
 
         ftrace_init_dyn_debugfs(d_tracer);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 7a4104cb95cb..5040d44fe5a3 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -9,7 +9,6 @@
 #include <linux/trace_seq.h>
 #include <linux/spinlock.h>
 #include <linux/irq_work.h>
-#include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/hardirq.h>
 #include <linux/kthread.h>      /* for self test */
@@ -23,7 +22,6 @@
 #include <linux/hash.h>
 #include <linux/list.h>
 #include <linux/cpu.h>
-#include <linux/fs.h>
 
 #include <asm/local.h>
 
@@ -447,7 +445,10 @@ int ring_buffer_print_page_header(struct trace_seq *s)
 struct rb_irq_work {
         struct irq_work                 work;
         wait_queue_head_t               waiters;
+        wait_queue_head_t               full_waiters;
         bool                            waiters_pending;
+        bool                            full_waiters_pending;
+        bool                            wakeup_full;
 };
 
 /*
@@ -529,6 +530,10 @@ static void rb_wake_up_waiters(struct irq_work *work)
         struct rb_irq_work *rbwork = container_of(work, struct rb_irq_work, work);
 
         wake_up_all(&rbwork->waiters);
+        if (rbwork->wakeup_full) {
+                rbwork->wakeup_full = false;
+                wake_up_all(&rbwork->full_waiters);
+        }
 }
 
 /**
@@ -553,9 +558,11 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
          * data in any cpu buffer, or a specific buffer, put the
          * caller on the appropriate wait queue.
          */
-        if (cpu == RING_BUFFER_ALL_CPUS)
+        if (cpu == RING_BUFFER_ALL_CPUS) {
                 work = &buffer->irq_work;
-        else {
+                /* Full only makes sense on per cpu reads */
+                full = false;
+        } else {
                 if (!cpumask_test_cpu(cpu, buffer->cpumask))
                         return -ENODEV;
                 cpu_buffer = buffer->buffers[cpu];
@@ -564,7 +571,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
 
 
         while (true) {
-                prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
+                if (full)
+                        prepare_to_wait(&work->full_waiters, &wait, TASK_INTERRUPTIBLE);
+                else
+                        prepare_to_wait(&work->waiters, &wait, TASK_INTERRUPTIBLE);
 
                 /*
                  * The events can happen in critical sections where
@@ -586,7 +596,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
                  * that is necessary is that the wake up happens after
                  * a task has been queued. It's OK for spurious wake ups.
                  */
-                work->waiters_pending = true;
+                if (full)
+                        work->full_waiters_pending = true;
+                else
+                        work->waiters_pending = true;
 
                 if (signal_pending(current)) {
                         ret = -EINTR;
@@ -615,7 +628,10 @@ int ring_buffer_wait(struct ring_buffer *buffer, int cpu, bool full)
                 schedule();
         }
 
-        finish_wait(&work->waiters, &wait);
+        if (full)
+                finish_wait(&work->full_waiters, &wait);
+        else
+                finish_wait(&work->waiters, &wait);