1 files changed, 267 insertions, 145 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index cda81ec58d9f..076fa6f0ee48 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -171,6 +171,13 @@ static struct trace_array	global_trace;
 
 static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
 
+int filter_current_check_discard(struct ftrace_event_call *call, void *rec,
+                                 struct ring_buffer_event *event)
+{
+        return filter_check_discard(call, rec, global_trace.buffer, event);
+}
+EXPORT_SYMBOL_GPL(filter_current_check_discard);
+
 cycle_t ftrace_now(int cpu)
 {
         u64 ts;
@@ -255,7 +262,8 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
 
 /* trace_flags holds trace_options default values */
 unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
-        TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME;
+        TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
+        TRACE_ITER_GRAPH_TIME;
 
 /**
  * trace_wake_up - wake up tasks waiting for trace input
@@ -317,6 +325,7 @@ static const char *trace_options[] = {
         "latency-format",
         "global-clock",
         "sleep-time",
+        "graph-time",
         NULL
 };
 
@@ -335,7 +344,7 @@ static raw_spinlock_t ftrace_max_lock =
 /*
  * Copy the new maximum trace into the separate maximum-trace
  * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
  */
 static void
 __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
@@ -402,17 +411,6 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
         return cnt;
 }
 
-static void
-trace_print_seq(struct seq_file *m, struct trace_seq *s)
-{
-        int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
-
-        s->buffer[len] = 0;
-        seq_puts(m, s->buffer);
-
-        trace_seq_init(s);
-}
-
 /**
  * update_max_tr - snapshot all trace buffers from global_trace to max_tr
  * @tr: tracer
@@ -641,6 +639,16 @@ void tracing_reset_online_cpus(struct trace_array *tr)
                 tracing_reset(tr, cpu);
 }
 
+void tracing_reset_current(int cpu)
+{
+        tracing_reset(&global_trace, cpu);
+}
+
+void tracing_reset_current_online_cpus(void)
+{
+        tracing_reset_online_cpus(&global_trace);
+}
+
 #define SAVED_CMDLINES 128
 #define NO_CMDLINE_MAP UINT_MAX
 static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
@@ -800,6 +808,7 @@ void trace_find_cmdline(int pid, char comm[])
                 return;
         }
 
+        preempt_disable();
         __raw_spin_lock(&trace_cmdline_lock);
         map = map_pid_to_cmdline[pid];
         if (map != NO_CMDLINE_MAP)
@@ -808,6 +817,7 @@ void trace_find_cmdline(int pid, char comm[])
                 strcpy(comm, "<...>");
 
         __raw_spin_unlock(&trace_cmdline_lock);
+        preempt_enable();
 }
 
 void tracing_record_cmdline(struct task_struct *tsk)
@@ -840,7 +850,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 }
 
 struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
-                                                    unsigned char type,
+                                                    int type,
                                                     unsigned long len,
                                                     unsigned long flags, int pc)
 {
@@ -883,30 +893,40 @@ void trace_buffer_unlock_commit(struct trace_array *tr,
 }
 
 struct ring_buffer_event *
-trace_current_buffer_lock_reserve(unsigned char type, unsigned long len,
+trace_current_buffer_lock_reserve(int type, unsigned long len,
                                   unsigned long flags, int pc)
 {
         return trace_buffer_lock_reserve(&global_trace,
                                          type, len, flags, pc);
 }
+EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve);
 
 void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
                                         unsigned long flags, int pc)
 {
-        return __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1);
+        __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1);
 }
+EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit);
 
 void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event,
                                         unsigned long flags, int pc)
 {
-        return __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0);
+        __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0);
+}
+EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit);
+
+void trace_current_buffer_discard_commit(struct ring_buffer_event *event)
+{
+        ring_buffer_discard_commit(global_trace.buffer, event);
 }
+EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit);
 
 void
 trace_function(struct trace_array *tr,
                unsigned long ip, unsigned long parent_ip, unsigned long flags,
                int pc)
 {
+        struct ftrace_event_call *call = &event_function;
         struct ring_buffer_event *event;
         struct ftrace_entry *entry;
 
@@ -921,7 +941,9 @@ trace_function(struct trace_array *tr,
         entry   = ring_buffer_event_data(event);
         entry->ip                       = ip;
         entry->parent_ip                = parent_ip;
-        ring_buffer_unlock_commit(tr->buffer, event);
+
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
 }
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
@@ -930,6 +952,7 @@ static int __trace_graph_entry(struct trace_array *tr,
                                 unsigned long flags,
                                 int pc)
 {
+        struct ftrace_event_call *call = &event_funcgraph_entry;
         struct ring_buffer_event *event;
         struct ftrace_graph_ent_entry *entry;
 
@@ -942,7 +965,8 @@ static int __trace_graph_entry(struct trace_array *tr,
                 return 0;
         entry   = ring_buffer_event_data(event);
         entry->graph_ent                        = *trace;
-        ring_buffer_unlock_commit(global_trace.buffer, event);
+        if (!filter_current_check_discard(call, entry, event))
+                ring_buffer_unlock_commit(global_trace.buffer, event);
 
         return 1;
 }
@@ -952,6 +976,7 @@ static void __trace_graph_return(struct trace_array *tr,
                                 unsigned long flags,
                                 int pc)
 {
+        struct ftrace_event_call *call = &event_funcgraph_exit;
         struct ring_buffer_event *event;
         struct ftrace_graph_ret_entry *entry;
 
@@ -964,7 +989,8 @@ static void __trace_graph_return(struct trace_array *tr,
                 return;
         entry   = ring_buffer_event_data(event);
         entry->ret                              = *trace;
-        ring_buffer_unlock_commit(global_trace.buffer, event);
+        if (!filter_current_check_discard(call, entry, event))
+                ring_buffer_unlock_commit(global_trace.buffer, event);
 }
 #endif
 
@@ -982,6 +1008,7 @@ static void __ftrace_trace_stack(struct trace_array *tr,
                                  int skip, int pc)
 {
 #ifdef CONFIG_STACKTRACE
+        struct ftrace_event_call *call = &event_kernel_stack;
         struct ring_buffer_event *event;
         struct stack_entry *entry;
         struct stack_trace trace;
@@ -999,7 +1026,8 @@ static void __ftrace_trace_stack(struct trace_array *tr,
         trace.entries           = entry->caller;
 
         save_stack_trace(&trace);
-        ring_buffer_unlock_commit(tr->buffer, event);
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
 #endif
 }
 
@@ -1024,6 +1052,7 @@ static void ftrace_trace_userstack(struct trace_array *tr,
                                    unsigned long flags, int pc)
 {
 #ifdef CONFIG_STACKTRACE
+        struct ftrace_event_call *call = &event_user_stack;
         struct ring_buffer_event *event;
         struct userstack_entry *entry;
         struct stack_trace trace;
@@ -1045,7 +1074,8 @@ static void ftrace_trace_userstack(struct trace_array *tr,
         trace.entries           = entry->caller;
 
         save_stack_trace_user(&trace);
-        ring_buffer_unlock_commit(tr->buffer, event);
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
 #endif
 }
 
@@ -1089,6 +1119,7 @@ tracing_sched_switch_trace(struct trace_array *tr,
                            struct task_struct *next,
                            unsigned long flags, int pc)
 {
+        struct ftrace_event_call *call = &event_context_switch;
         struct ring_buffer_event *event;
         struct ctx_switch_entry *entry;
 
@@ -1104,7 +1135,9 @@ tracing_sched_switch_trace(struct trace_array *tr,
         entry->next_prio                = next->prio;
         entry->next_state               = next->state;
         entry->next_cpu = task_cpu(next);
-        trace_buffer_unlock_commit(tr, event, flags, pc);
+
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                trace_buffer_unlock_commit(tr, event, flags, pc);
 }
 
 void
@@ -1113,6 +1146,7 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
                            struct task_struct *curr,
                            unsigned long flags, int pc)
 {
+        struct ftrace_event_call *call = &event_wakeup;
         struct ring_buffer_event *event;
         struct ctx_switch_entry *entry;
 
@@ -1129,7 +1163,8 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
         entry->next_state               = wakee->state;
         entry->next_cpu                 = task_cpu(wakee);
 
-        ring_buffer_unlock_commit(tr->buffer, event);
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
         ftrace_trace_stack(tr, flags, 6, pc);
         ftrace_trace_userstack(tr, flags, pc);
 }
@@ -1230,11 +1265,13 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
                 (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
         static u32 trace_buf[TRACE_BUF_SIZE];
 
+        struct ftrace_event_call *call = &event_bprint;
         struct ring_buffer_event *event;
         struct trace_array *tr = &global_trace;
         struct trace_array_cpu *data;
         struct bprint_entry *entry;
         unsigned long flags;
+        int disable;
         int resched;
         int cpu, len = 0, size, pc;
 
@@ -1249,7 +1286,8 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
         cpu = raw_smp_processor_id();
         data = tr->data[cpu];
 
-        if (unlikely(atomic_read(&data->disabled)))
+        disable = atomic_inc_return(&data->disabled);
+        if (unlikely(disable != 1))
                 goto out;
 
         /* Lockdep uses trace_printk for lock tracing */
@@ -1269,13 +1307,15 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
         entry->fmt                      = fmt;
 
         memcpy(entry->buf, trace_buf, sizeof(u32) * len);
-        ring_buffer_unlock_commit(tr->buffer, event);
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
 
 out_unlock:
         __raw_spin_unlock(&trace_buf_lock);
         local_irq_restore(flags);
 
 out:
+        atomic_dec_return(&data->disabled);
         ftrace_preempt_enable(resched);
         unpause_graph_tracing();
 
@@ -1288,12 +1328,14 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
         static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED;
         static char trace_buf[TRACE_BUF_SIZE];
 
+        struct ftrace_event_call *call = &event_print;
         struct ring_buffer_event *event;
         struct trace_array *tr = &global_trace;
         struct trace_array_cpu *data;
         int cpu, len = 0, size, pc;
         struct print_entry *entry;
         unsigned long irq_flags;
+        int disable;
 
         if (tracing_disabled || tracing_selftest_running)
                 return 0;
@@ -1303,7 +1345,8 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
         cpu = raw_smp_processor_id();
         data = tr->data[cpu];
 
-        if (unlikely(atomic_read(&data->disabled)))
+        disable = atomic_inc_return(&data->disabled);
+        if (unlikely(disable != 1))
                 goto out;
 
         pause_graph_tracing();
@@ -1323,13 +1366,15 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
 
         memcpy(&entry->buf, trace_buf, len);
         entry->buf[len] = 0;
-        ring_buffer_unlock_commit(tr->buffer, event);
+        if (!filter_check_discard(call, entry, tr->buffer, event))
+                ring_buffer_unlock_commit(tr->buffer, event);
 
  out_unlock:
         __raw_spin_unlock(&trace_buf_lock);
         raw_local_irq_restore(irq_flags);
         unpause_graph_tracing();
  out:
+        atomic_dec_return(&data->disabled);
         preempt_enable_notrace();
 
         return len;
@@ -1526,12 +1571,14 @@ static void *s_start(struct seq_file *m, loff_t *pos)
                 p = s_next(m, p, &l);
         }
 
+        trace_event_read_lock();
         return p;
 }
 
 static void s_stop(struct seq_file *m, void *p)
 {
         atomic_dec(&trace_record_cmdline_disabled);
+        trace_event_read_unlock();
 }
 
 static void print_lat_help_header(struct seq_file *m)
@@ -1774,6 +1821,7 @@ static int trace_empty(struct trace_iterator *iter)
         return 1;
 }
 
+/*  Called with trace_event_read_lock() held. */
 static enum print_line_t print_trace_line(struct trace_iterator *iter)
 {
         enum print_line_t ret;
@@ -2143,11 +2191,12 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
         if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
                 return -ENOMEM;
 
-        mutex_lock(&tracing_cpumask_update_lock);
         err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
         if (err)
                 goto err_unlock;
 
+        mutex_lock(&tracing_cpumask_update_lock);
+
         local_irq_disable();
         __raw_spin_lock(&ftrace_max_lock);
         for_each_tracing_cpu(cpu) {
@@ -2175,8 +2224,7 @@ tracing_cpumask_write(struct file *filp, const char __user *ubuf,
         return count;
 
 err_unlock:
-        mutex_unlock(&tracing_cpumask_update_lock);
-        free_cpumask_var(tracing_cpumask);
+        free_cpumask_var(tracing_cpumask_new);
 
         return err;
 }
@@ -2366,21 +2414,20 @@ static const struct file_operations tracing_iter_fops = {
 
 static const char readme_msg[] =
         "tracing mini-HOWTO:\n\n"
-        "# mkdir /debug\n"
-        "# mount -t debugfs nodev /debug\n\n"
-        "# cat /debug/tracing/available_tracers\n"
+        "# mount -t debugfs nodev /sys/kernel/debug\n\n"
+        "# cat /sys/kernel/debug/tracing/available_tracers\n"
         "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
-        "# cat /debug/tracing/current_tracer\n"
+        "# cat /sys/kernel/debug/tracing/current_tracer\n"
         "nop\n"
-        "# echo sched_switch > /debug/tracing/current_tracer\n"
-        "# cat /debug/tracing/current_tracer\n"
+        "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+        "# cat /sys/kernel/debug/tracing/current_tracer\n"
         "sched_switch\n"
-        "# cat /debug/tracing/trace_options\n"
+        "# cat /sys/kernel/debug/tracing/trace_options\n"
         "noprint-parent nosym-offset nosym-addr noverbose\n"
-        "# echo print-parent > /debug/tracing/trace_options\n"
-        "# echo 1 > /debug/tracing/tracing_enabled\n"
-        "# cat /debug/tracing/trace > /tmp/trace.txt\n"
-        "# echo 0 > /debug/tracing/tracing_enabled\n"
+        "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
+        "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+        "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
+        "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
 ;
 
 static ssize_t
@@ -2397,6 +2444,56 @@ static const struct file_operations tracing_readme_fops = {
 };
 
 static ssize_t
+tracing_saved_cmdlines_read(struct file *file, char __user *ubuf,
+                                size_t cnt, loff_t *ppos)
+{
+        char *buf_comm;
+        char *file_buf;
+        char *buf;
+        int len = 0;
+        int pid;
+        int i;
+
+        file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL);
+        if (!file_buf)
+                return -ENOMEM;
+
+        buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL);
+        if (!buf_comm) {
+                kfree(file_buf);
+                return -ENOMEM;
+        }
+
+        buf = file_buf;
+
+        for (i = 0; i < SAVED_CMDLINES; i++) {
+                int r;
+
+                pid = map_cmdline_to_pid[i];
+                if (pid == -1 || pid == NO_CMDLINE_MAP)
+                        continue;
+
+                trace_find_cmdline(pid, buf_comm);
+                r = sprintf(buf, "%d %s\n", pid, buf_comm);
+                buf += r;
+                len += r;
+        }
+
+        len = simple_read_from_buffer(ubuf, cnt, ppos,
+                                      file_buf, len);
+
+        kfree(file_buf);
+        kfree(buf_comm);
+
+        return len;
+}
+
+static const struct file_operations tracing_saved_cmdlines_fops = {
+    .open       = tracing_open_generic,
+    .read       = tracing_saved_cmdlines_read,
+};
+
+static ssize_t
 tracing_ctrl_read(struct file *filp, char __user *ubuf,
                   size_t cnt, loff_t *ppos)
 {
@@ -2728,6 +2825,9 @@ static int tracing_open_pipe(struct inode *inode, struct file *filp)
         /* trace pipe does not show start of buffer */
         cpumask_setall(iter->started);
 
+        if (trace_flags & TRACE_ITER_LATENCY_FMT)
+                iter->iter_flags |= TRACE_FILE_LAT_FMT;
+
         iter->cpu_file = cpu_file;
         iter->tr = &global_trace;
         mutex_init(&iter->mutex);
@@ -2915,6 +3015,7 @@ waitagain:
                offsetof(struct trace_iterator, seq));
         iter->pos = -1;
 
+        trace_event_read_lock();
         while (find_next_entry_inc(iter) != NULL) {
                 enum print_line_t ret;
                 int len = iter->seq.len;
@@ -2931,6 +3032,7 @@ waitagain:
                 if (iter->seq.len >= cnt)
                         break;
         }
+        trace_event_read_unlock();
 
         /* Now copy what we have to the user */
         sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
@@ -3053,6 +3155,8 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
                 goto out_err;
         }
 
+        trace_event_read_lock();
+
         /* Fill as many pages as possible. */
         for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
                 pages[i] = alloc_page(GFP_KERNEL);
@@ -3075,6 +3179,7 @@ static ssize_t tracing_splice_read_pipe(struct file *filp,
                 trace_seq_init(&iter->seq);
         }
 
+        trace_event_read_unlock();
         mutex_unlock(&iter->mutex);
 
         spd.nr_pages = i;
@@ -3425,7 +3530,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 .spd_release    = buffer_spd_release,
         };
         struct buffer_ref *ref;
-        int size, i;
+        int entries, size, i;
         size_t ret;
 
         if (*ppos & (PAGE_SIZE - 1)) {
@@ -3440,7 +3545,9 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 len &= PAGE_MASK;
         }
 
-        for (i = 0; i < PIPE_BUFFERS && len; i++, len -= PAGE_SIZE) {
+        entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
+
+        for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) {
                 struct page *page;
                 int r;
 
@@ -3457,7 +3564,7 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 }
 
                 r = ring_buffer_read_page(ref->buffer, &ref->page,
-                                          len, info->cpu, 0);
+                                          len, info->cpu, 1);
                 if (r < 0) {
                         ring_buffer_free_read_page(ref->buffer,
                                                    ref->page);
@@ -3481,6 +3588,8 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
                 spd.partial[i].private = (unsigned long)ref;
                 spd.nr_pages++;
                 *ppos += PAGE_SIZE;
+
+                entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
         }
 
         spd.nr_pages = i;
@@ -3508,6 +3617,45 @@ static const struct file_operations tracing_buffers_fops = {
         .llseek         = no_llseek,
 };
 
+static ssize_t
+tracing_stats_read(struct file *filp, char __user *ubuf,
+                   size_t count, loff_t *ppos)
+{
+        unsigned long cpu = (unsigned long)filp->private_data;
+        struct trace_array *tr = &global_trace;
+        struct trace_seq *s;
+        unsigned long cnt;
+
+        s = kmalloc(sizeof(*s), GFP_KERNEL);
+        if (!s)
+                return ENOMEM;
+
+        trace_seq_init(s);
+
+        cnt = ring_buffer_entries_cpu(tr->buffer, cpu);
+        trace_seq_printf(s, "entries: %ld\n", cnt);
+
+        cnt = ring_buffer_overrun_cpu(tr->buffer, cpu);
+        trace_seq_printf(s, "overrun: %ld\n", cnt);
+
+        cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu);
+        trace_seq_printf(s, "commit overrun: %ld\n", cnt);
+
+        cnt = ring_buffer_nmi_dropped_cpu(tr->buffer, cpu);
+        trace_seq_printf(s, "nmi dropped: %ld\n", cnt);
+
+        count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
+
+        kfree(s);
+
+        return count;
+}
+
+static const struct file_operations tracing_stats_fops = {
+        .open           = tracing_open_generic,
+        .read           = tracing_stats_read,
+};
+
 #ifdef CONFIG_DYNAMIC_FTRACE
 
 int __weak ftrace_arch_read_dyn_info(char *buf, int size)
@@ -3597,7 +3745,7 @@ struct dentry *tracing_dentry_percpu(void)
 static void tracing_init_debugfs_percpu(long cpu)
 {
         struct dentry *d_percpu = tracing_dentry_percpu();
-        struct dentry *entry, *d_cpu;
+        struct dentry *d_cpu;
         /* strlen(cpu) + MAX(log10(cpu)) + '\0' */
         char cpu_dir[7];
 
@@ -3612,21 +3760,18 @@ static void tracing_init_debugfs_percpu(long cpu)
         }
 
         /* per cpu trace_pipe */
-        entry = debugfs_create_file("trace_pipe", 0444, d_cpu,
-                                (void *) cpu, &tracing_pipe_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'trace_pipe' entry\n");
+        trace_create_file("trace_pipe", 0444, d_cpu,
+                        (void *) cpu, &tracing_pipe_fops);
 
         /* per cpu trace */
-        entry = debugfs_create_file("trace", 0644, d_cpu,
-                                (void *) cpu, &tracing_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'trace' entry\n");
+        trace_create_file("trace", 0644, d_cpu,
+                        (void *) cpu, &tracing_fops);
 
-        entry = debugfs_create_file("trace_pipe_raw", 0444, d_cpu,
-                                    (void *) cpu, &tracing_buffers_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'trace_pipe_raw' entry\n");
+        trace_create_file("trace_pipe_raw", 0444, d_cpu,
+                        (void *) cpu, &tracing_buffers_fops);
+
+        trace_create_file("stats", 0444, d_cpu,
+                        (void *) cpu, &tracing_stats_fops);
 }
 
 #ifdef CONFIG_FTRACE_SELFTEST
@@ -3782,6 +3927,22 @@ static const struct file_operations trace_options_core_fops = {
         .write = trace_options_core_write,
 };
 
+struct dentry *trace_create_file(const char *name,
+                                 mode_t mode,
+                                 struct dentry *parent,
+                                 void *data,
+                                 const struct file_operations *fops)
+{
+        struct dentry *ret;
+
+        ret = debugfs_create_file(name, mode, parent, data, fops);
+        if (!ret)
+                pr_warning("Could not create debugfs '%s' entry\n", name);
+
+        return ret;
+}
+
+
 static struct dentry *trace_options_init_dentry(void)
 {
         struct dentry *d_tracer;
@@ -3809,7 +3970,6 @@ create_trace_option_file(struct trace_option_dentry *topt,
                          struct tracer_opt *opt)
 {
         struct dentry *t_options;
-        struct dentry *entry;
 
         t_options = trace_options_init_dentry();
         if (!t_options)
@@ -3818,11 +3978,9 @@ create_trace_option_file(struct trace_option_dentry *topt,
         topt->flags = flags;
         topt->opt = opt;
 
-        entry = debugfs_create_file(opt->name, 0644, t_options, topt,
+        topt->entry = trace_create_file(opt->name, 0644, t_options, topt,
                                     &trace_options_fops);
 
-        topt->entry = entry;
-
 }
 
 static struct trace_option_dentry *
@@ -3877,123 +4035,84 @@ static struct dentry *
 create_trace_option_core_file(const char *option, long index)
 {
         struct dentry *t_options;
-        struct dentry *entry;
 
         t_options = trace_options_init_dentry();
         if (!t_options)
                 return NULL;
 
-        entry = debugfs_create_file(option, 0644, t_options, (void *)index,
+        return trace_create_file(option, 0644, t_options, (void *)index,
                                     &trace_options_core_fops);
-
-        return entry;
 }
 
 static __init void create_trace_options_dir(void)
 {
         struct dentry *t_options;
-        struct dentry *entry;
         int i;
 
         t_options = trace_options_init_dentry();
         if (!t_options)
                 return;
 
-        for (i = 0; trace_options[i]; i++) {
-                entry = create_trace_option_core_file(trace_options[i], i);
-                if (!entry)
-                        pr_warning("Could not create debugfs %s entry\n",
-                                   trace_options[i]);
-        }
+        for (i = 0; trace_options[i]; i++)
+                create_trace_option_core_file(trace_options[i], i);
 }
 
 static __init int tracer_init_debugfs(void)
 {
         struct dentry *d_tracer;
-        struct dentry *entry;
         int cpu;
 
         d_tracer = tracing_init_dentry();
 
-        entry = debugfs_create_file("tracing_enabled", 0644, d_tracer,
-                                    &global_trace, &tracing_ctrl_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
+        trace_create_file("tracing_enabled", 0644, d_tracer,
+                        &global_trace, &tracing_ctrl_fops);
 
-        entry = debugfs_create_file("trace_options", 0644, d_tracer,
-                                    NULL, &tracing_iter_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'trace_options' entry\n");
+        trace_create_file("trace_options", 0644, d_tracer,
+                        NULL, &tracing_iter_fops);
 
-        create_trace_options_dir();
+        trace_create_file("tracing_cpumask", 0644, d_tracer,
+                        NULL, &tracing_cpumask_fops);
 
-        entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer,
-                                    NULL, &tracing_cpumask_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'tracing_cpumask' entry\n");
-
-        entry = debugfs_create_file("trace", 0644, d_tracer,
-                                 (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'trace' entry\n");
-
-        entry = debugfs_create_file("available_tracers", 0444, d_tracer,
-                                    &global_trace, &show_traces_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'available_tracers' entry\n");
-
-        entry = debugfs_create_file("current_tracer", 0444, d_tracer,
-                                    &global_trace, &set_tracer_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'current_tracer' entry\n");
-
-        entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer,
-                                    &tracing_max_latency,
-                                    &tracing_max_lat_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'tracing_max_latency' entry\n");
-
-        entry = debugfs_create_file("tracing_thresh", 0644, d_tracer,
-                                    &tracing_thresh, &tracing_max_lat_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'tracing_thresh' entry\n");
-        entry = debugfs_create_file("README", 0644, d_tracer,
-                                    NULL, &tracing_readme_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs 'README' entry\n");
-
-        entry = debugfs_create_file("trace_pipe", 0444, d_tracer,
+        trace_create_file("trace", 0644, d_tracer,
+                        (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
+
+        trace_create_file("available_tracers", 0444, d_tracer,
+                        &global_trace, &show_traces_fops);
+
+        trace_create_file("current_tracer", 0644, d_tracer,
+                        &global_trace, &set_tracer_fops);
+
+        trace_create_file("tracing_max_latency", 0644, d_tracer,
+                        &tracing_max_latency, &tracing_max_lat_fops);
+
+        trace_create_file("tracing_thresh", 0644, d_tracer,
+                        &tracing_thresh, &tracing_max_lat_fops);
+
+        trace_create_file("README", 0444, d_tracer,
+                        NULL, &tracing_readme_fops);
+
+        trace_create_file("trace_pipe", 0444, d_tracer,
                         (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'trace_pipe' entry\n");
-
-        entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer,
-                                    &global_trace, &tracing_entries_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'buffer_size_kb' entry\n");
-
-        entry = debugfs_create_file("trace_marker", 0220, d_tracer,
-                                    NULL, &tracing_mark_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'trace_marker' entry\n");
+
+        trace_create_file("buffer_size_kb", 0644, d_tracer,
+                        &global_trace, &tracing_entries_fops);
+
+        trace_create_file("trace_marker", 0220, d_tracer,
+                        NULL, &tracing_mark_fops);
+
+        trace_create_file("saved_cmdlines", 0444, d_tracer,
+                        NULL, &tracing_saved_cmdlines_fops);
 
 #ifdef CONFIG_DYNAMIC_FTRACE
-        entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
-                                    &ftrace_update_tot_cnt,
-                                    &tracing_dyn_info_fops);
-        if (!entry)
-                pr_warning("Could not create debugfs "
-                           "'dyn_ftrace_total_info' entry\n");
+        trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
+                        &ftrace_update_tot_cnt, &tracing_dyn_info_fops);
 #endif
 #ifdef CONFIG_SYSPROF_TRACER
         init_tracer_sysprof_debugfs(d_tracer);
 #endif
 
+        create_trace_options_dir();
+
         for_each_tracing_cpu(cpu)
                 tracing_init_debugfs_percpu(cpu);
 
@@ -4064,7 +4183,8 @@ trace_printk_seq(struct trace_seq *s)
 
 static void __ftrace_dump(bool disable_tracing)
 {
-        static DEFINE_SPINLOCK(ftrace_dump_lock);
+        static raw_spinlock_t ftrace_dump_lock =
+                (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
         /* use static because iter can be a bit big for the stack */
         static struct trace_iterator iter;
         unsigned int old_userobj;
@@ -4073,7 +4193,8 @@ static void __ftrace_dump(bool disable_tracing)
         int cnt = 0, cpu;
 
         /* only one dump */
-        spin_lock_irqsave(&ftrace_dump_lock, flags);
+        local_irq_save(flags);
+        __raw_spin_lock(&ftrace_dump_lock);
         if (dump_ran)
                 goto out;
 
@@ -4145,7 +4266,8 @@ static void __ftrace_dump(bool disable_tracing)
         }
 
  out:
-        spin_unlock_irqrestore(&ftrace_dump_lock, flags);
+        __raw_spin_unlock(&ftrace_dump_lock);
+        local_irq_restore(flags);
 }
 
 /* By default: disable tracing after the dump */