Merge commit 'v2.6.31-rc9' into tracing/core
[pandora-kernel.git] / kernel / trace / trace.c
index 8c35839..5c75dee 100644 (file)
 
 #define TRACE_BUFFER_FLAGS     (RB_FL_OVERWRITE)
 
-unsigned long __read_mostly    tracing_max_latency;
-unsigned long __read_mostly    tracing_thresh;
-
 /*
  * On boot up, the ring buffer is set to the minimum size, so that
  * we do not waste memory on systems that are not using tracing.
  */
-static int ring_buffer_expanded;
+int ring_buffer_expanded;
 
 /*
  * We need to change this state when a selftest is running.
@@ -64,7 +61,7 @@ static bool __read_mostly tracing_selftest_running;
 /*
  * If a tracer is running, we do not want to run SELFTEST.
  */
-static bool __read_mostly tracing_selftest_disabled;
+bool __read_mostly tracing_selftest_disabled;
 
 /* For tracers that don't implement custom flags */
 static struct tracer_opt dummy_tracer_opt[] = {
@@ -89,7 +86,7 @@ static int dummy_set_flag(u32 old_flags, u32 bit, int set)
  */
 static int tracing_disabled = 1;
 
-static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
+DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
 
 static inline void ftrace_disable_cpu(void)
 {
@@ -172,10 +169,11 @@ 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,
+int filter_current_check_discard(struct ring_buffer *buffer,
+                                struct ftrace_event_call *call, void *rec,
                                 struct ring_buffer_event *event)
 {
-       return filter_check_discard(call, rec, global_trace.buffer, event);
+       return filter_check_discard(call, rec, buffer, event);
 }
 EXPORT_SYMBOL_GPL(filter_current_check_discard);
 
@@ -266,6 +264,9 @@ unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
        TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
        TRACE_ITER_GRAPH_TIME;
 
+static int trace_stop_count;
+static DEFINE_SPINLOCK(tracing_start_lock);
+
 /**
  * trace_wake_up - wake up tasks waiting for trace input
  *
@@ -323,50 +324,20 @@ static const char *trace_options[] = {
        "printk-msg-only",
        "context-info",
        "latency-format",
-       "global-clock",
        "sleep-time",
        "graph-time",
        NULL
 };
 
-/*
- * ftrace_max_lock is used to protect the swapping of buffers
- * when taking a max snapshot. The buffers themselves are
- * protected by per_cpu spinlocks. But the action of the swap
- * needs its own lock.
- *
- * This is defined as a raw_spinlock_t in order to help
- * with performance when lockdep debugging is enabled.
- */
-static raw_spinlock_t ftrace_max_lock =
-       (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
-
-/*
- * Copy the new maximum trace into the separate maximum-trace
- * structure. (this way the maximum trace is permanently saved,
- * 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)
-{
-       struct trace_array_cpu *data = tr->data[cpu];
-
-       max_tr.cpu = cpu;
-       max_tr.time_start = data->preempt_timestamp;
+static struct {
+       u64 (*func)(void);
+       const char *name;
+} trace_clocks[] = {
+       { trace_clock_local,    "local" },
+       { trace_clock_global,   "global" },
+};
 
-       data = max_tr.data[cpu];
-       data->saved_latency = tracing_max_latency;
-
-       memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
-       data->pid = tsk->pid;
-       data->uid = task_uid(tsk);
-       data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
-       data->policy = tsk->policy;
-       data->rt_priority = tsk->rt_priority;
-
-       /* record this tasks comm */
-       tracing_record_cmdline(tsk);
-}
+int trace_clock_id;
 
 ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
 {
@@ -411,6 +382,56 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
        return cnt;
 }
 
+/*
+ * ftrace_max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a raw_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ *
+ * It is also used in other places outside the update_max_tr
+ * so it needs to be defined outside of the
+ * CONFIG_TRACER_MAX_TRACE.
+ */
+static raw_spinlock_t ftrace_max_lock =
+       (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+unsigned long __read_mostly    tracing_max_latency;
+unsigned long __read_mostly    tracing_thresh;
+
+/*
+ * Copy the new maximum trace into the separate maximum-trace
+ * structure. (this way the maximum trace is permanently saved,
+ * 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)
+{
+       struct trace_array_cpu *data = tr->data[cpu];
+       struct trace_array_cpu *max_data = tr->data[cpu];
+
+       max_tr.cpu = cpu;
+       max_tr.time_start = data->preempt_timestamp;
+
+       max_data = max_tr.data[cpu];
+       max_data->saved_latency = tracing_max_latency;
+       max_data->critical_start = data->critical_start;
+       max_data->critical_end = data->critical_end;
+
+       memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
+       max_data->pid = tsk->pid;
+       max_data->uid = task_uid(tsk);
+       max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
+       max_data->policy = tsk->policy;
+       max_data->rt_priority = tsk->rt_priority;
+
+       /* record this tasks comm */
+       tracing_record_cmdline(tsk);
+}
+
 /**
  * update_max_tr - snapshot all trace buffers from global_trace to max_tr
  * @tr: tracer
@@ -425,16 +446,15 @@ update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
 {
        struct ring_buffer *buf = tr->buffer;
 
+       if (trace_stop_count)
+               return;
+
        WARN_ON_ONCE(!irqs_disabled());
        __raw_spin_lock(&ftrace_max_lock);
 
        tr->buffer = max_tr.buffer;
        max_tr.buffer = buf;
 
-       ftrace_disable_cpu();
-       ring_buffer_reset(tr->buffer);
-       ftrace_enable_cpu();
-
        __update_max_tr(tr, tsk, cpu);
        __raw_spin_unlock(&ftrace_max_lock);
 }
@@ -452,21 +472,35 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
 {
        int ret;
 
+       if (trace_stop_count)
+               return;
+
        WARN_ON_ONCE(!irqs_disabled());
        __raw_spin_lock(&ftrace_max_lock);
 
        ftrace_disable_cpu();
 
-       ring_buffer_reset(max_tr.buffer);
        ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu);
 
+       if (ret == -EBUSY) {
+               /*
+                * We failed to swap the buffer due to a commit taking
+                * place on this CPU. We fail to record, but we reset
+                * the max trace buffer (no one writes directly to it)
+                * and flag that it failed.
+                */
+               trace_array_printk(&max_tr, _THIS_IP_,
+                       "Failed to swap buffers due to commit in progress\n");
+       }
+
        ftrace_enable_cpu();
 
-       WARN_ON_ONCE(ret && ret != -EAGAIN);
+       WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
 
        __update_max_tr(tr, tsk, cpu);
        __raw_spin_unlock(&ftrace_max_lock);
 }
+#endif /* CONFIG_TRACER_MAX_TRACE */
 
 /**
  * register_tracer - register a tracer with the ftrace system.
@@ -523,7 +557,6 @@ __acquires(kernel_lock)
        if (type->selftest && !tracing_selftest_disabled) {
                struct tracer *saved_tracer = current_trace;
                struct trace_array *tr = &global_trace;
-               int i;
 
                /*
                 * Run a selftest on this tracer.
@@ -532,8 +565,7 @@ __acquires(kernel_lock)
                 * internal tracing to verify that everything is in order.
                 * If we fail, we do not register this tracer.
                 */
-               for_each_tracing_cpu(i)
-                       tracing_reset(tr, i);
+               tracing_reset_online_cpus(tr);
 
                current_trace = type;
                /* the test is responsible for initializing and enabling */
@@ -546,8 +578,7 @@ __acquires(kernel_lock)
                        goto out;
                }
                /* Only reset on passing, to avoid touching corrupted buffers */
-               for_each_tracing_cpu(i)
-                       tracing_reset(tr, i);
+               tracing_reset_online_cpus(tr);
 
                printk(KERN_CONT "PASSED\n");
        }
@@ -622,21 +653,42 @@ void unregister_tracer(struct tracer *type)
        mutex_unlock(&trace_types_lock);
 }
 
-void tracing_reset(struct trace_array *tr, int cpu)
+static void __tracing_reset(struct trace_array *tr, int cpu)
 {
        ftrace_disable_cpu();
        ring_buffer_reset_cpu(tr->buffer, cpu);
        ftrace_enable_cpu();
 }
 
+void tracing_reset(struct trace_array *tr, int cpu)
+{
+       struct ring_buffer *buffer = tr->buffer;
+
+       ring_buffer_record_disable(buffer);
+
+       /* Make sure all commits have finished */
+       synchronize_sched();
+       __tracing_reset(tr, cpu);
+
+       ring_buffer_record_enable(buffer);
+}
+
 void tracing_reset_online_cpus(struct trace_array *tr)
 {
+       struct ring_buffer *buffer = tr->buffer;
        int cpu;
 
+       ring_buffer_record_disable(buffer);
+
+       /* Make sure all commits have finished */
+       synchronize_sched();
+
        tr->time_start = ftrace_now(tr->cpu);
 
        for_each_online_cpu(cpu)
-               tracing_reset(tr, cpu);
+               __tracing_reset(tr, cpu);
+
+       ring_buffer_record_enable(buffer);
 }
 
 void tracing_reset_current(int cpu)
@@ -667,9 +719,6 @@ static void trace_init_cmdlines(void)
        cmdline_idx = 0;
 }
 
-static int trace_stop_count;
-static DEFINE_SPINLOCK(tracing_start_lock);
-
 /**
  * ftrace_off_permanent - disable all ftrace code permanently
  *
@@ -850,14 +899,15 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 }
 EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
 
-struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
-                                                   int type,
-                                                   unsigned long len,
-                                                   unsigned long flags, int pc)
+struct ring_buffer_event *
+trace_buffer_lock_reserve(struct ring_buffer *buffer,
+                         int type,
+                         unsigned long len,
+                         unsigned long flags, int pc)
 {
        struct ring_buffer_event *event;
 
-       event = ring_buffer_lock_reserve(tr->buffer, len);
+       event = ring_buffer_lock_reserve(buffer, len);
        if (event != NULL) {
                struct trace_entry *ent = ring_buffer_event_data(event);
 
@@ -867,58 +917,60 @@ struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
 
        return event;
 }
-static void ftrace_trace_stack(struct trace_array *tr,
-                              unsigned long flags, int skip, int pc);
-static void ftrace_trace_userstack(struct trace_array *tr,
-                                  unsigned long flags, int pc);
 
-static inline void __trace_buffer_unlock_commit(struct trace_array *tr,
-                                       struct ring_buffer_event *event,
-                                       unsigned long flags, int pc,
-                                       int wake)
+static inline void
+__trace_buffer_unlock_commit(struct ring_buffer *buffer,
+                            struct ring_buffer_event *event,
+                            unsigned long flags, int pc,
+                            int wake)
 {
-       ring_buffer_unlock_commit(tr->buffer, event);
+       ring_buffer_unlock_commit(buffer, event);
 
-       ftrace_trace_stack(tr, flags, 6, pc);
-       ftrace_trace_userstack(tr, flags, pc);
+       ftrace_trace_stack(buffer, flags, 6, pc);
+       ftrace_trace_userstack(buffer, flags, pc);
 
        if (wake)
                trace_wake_up();
 }
 
-void trace_buffer_unlock_commit(struct trace_array *tr,
-                                       struct ring_buffer_event *event,
-                                       unsigned long flags, int pc)
+void trace_buffer_unlock_commit(struct ring_buffer *buffer,
+                               struct ring_buffer_event *event,
+                               unsigned long flags, int pc)
 {
-       __trace_buffer_unlock_commit(tr, event, flags, pc, 1);
+       __trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
 }
 
 struct ring_buffer_event *
-trace_current_buffer_lock_reserve(int type, unsigned long len,
+trace_current_buffer_lock_reserve(struct ring_buffer **current_rb,
+                                 int type, unsigned long len,
                                  unsigned long flags, int pc)
 {
-       return trace_buffer_lock_reserve(&global_trace,
+       *current_rb = global_trace.buffer;
+       return trace_buffer_lock_reserve(*current_rb,
                                         type, len, flags, pc);
 }
 EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve);
 
-void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
+void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
+                                       struct ring_buffer_event *event,
                                        unsigned long flags, int pc)
 {
-       __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1);
+       __trace_buffer_unlock_commit(buffer, 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)
+void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
+                                      struct ring_buffer_event *event,
+                                      unsigned long flags, int pc)
 {
-       __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0);
+       __trace_buffer_unlock_commit(buffer, event, flags, pc, 0);
 }
 EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit);
 
-void trace_current_buffer_discard_commit(struct ring_buffer_event *event)
+void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
+                                        struct ring_buffer_event *event)
 {
-       ring_buffer_discard_commit(global_trace.buffer, event);
+       ring_buffer_discard_commit(buffer, event);
 }
 EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit);
 
@@ -928,6 +980,7 @@ trace_function(struct trace_array *tr,
               int pc)
 {
        struct ftrace_event_call *call = &event_function;
+       struct ring_buffer *buffer = tr->buffer;
        struct ring_buffer_event *event;
        struct ftrace_entry *entry;
 
@@ -935,7 +988,7 @@ trace_function(struct trace_array *tr,
        if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
                return;
 
-       event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry),
+       event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
                                          flags, pc);
        if (!event)
                return;
@@ -943,58 +996,10 @@ trace_function(struct trace_array *tr,
        entry->ip                       = ip;
        entry->parent_ip                = parent_ip;
 
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               ring_buffer_unlock_commit(tr->buffer, event);
-}
-
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int __trace_graph_entry(struct trace_array *tr,
-                               struct ftrace_graph_ent *trace,
-                               unsigned long flags,
-                               int pc)
-{
-       struct ftrace_event_call *call = &event_funcgraph_entry;
-       struct ring_buffer_event *event;
-       struct ftrace_graph_ent_entry *entry;
-
-       if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
-               return 0;
-
-       event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
-                                         sizeof(*entry), flags, pc);
-       if (!event)
-               return 0;
-       entry   = ring_buffer_event_data(event);
-       entry->graph_ent                        = *trace;
-       if (!filter_current_check_discard(call, entry, event))
-               ring_buffer_unlock_commit(global_trace.buffer, event);
-
-       return 1;
+       if (!filter_check_discard(call, entry, buffer, event))
+               ring_buffer_unlock_commit(buffer, event);
 }
 
-static void __trace_graph_return(struct trace_array *tr,
-                               struct ftrace_graph_ret *trace,
-                               unsigned long flags,
-                               int pc)
-{
-       struct ftrace_event_call *call = &event_funcgraph_exit;
-       struct ring_buffer_event *event;
-       struct ftrace_graph_ret_entry *entry;
-
-       if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
-               return;
-
-       event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
-                                         sizeof(*entry), flags, pc);
-       if (!event)
-               return;
-       entry   = ring_buffer_event_data(event);
-       entry->ret                              = *trace;
-       if (!filter_current_check_discard(call, entry, event))
-               ring_buffer_unlock_commit(global_trace.buffer, event);
-}
-#endif
-
 void
 ftrace(struct trace_array *tr, struct trace_array_cpu *data,
        unsigned long ip, unsigned long parent_ip, unsigned long flags,
@@ -1004,17 +1009,17 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data,
                trace_function(tr, ip, parent_ip, flags, pc);
 }
 
-static void __ftrace_trace_stack(struct trace_array *tr,
+#ifdef CONFIG_STACKTRACE
+static void __ftrace_trace_stack(struct ring_buffer *buffer,
                                 unsigned long flags,
                                 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;
 
-       event = trace_buffer_lock_reserve(tr, TRACE_STACK,
+       event = trace_buffer_lock_reserve(buffer, TRACE_STACK,
                                          sizeof(*entry), flags, pc);
        if (!event)
                return;
@@ -1027,32 +1032,28 @@ static void __ftrace_trace_stack(struct trace_array *tr,
        trace.entries           = entry->caller;
 
        save_stack_trace(&trace);
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+       if (!filter_check_discard(call, entry, buffer, event))
+               ring_buffer_unlock_commit(buffer, event);
 }
 
-static void ftrace_trace_stack(struct trace_array *tr,
-                              unsigned long flags,
-                              int skip, int pc)
+void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
+                       int skip, int pc)
 {
        if (!(trace_flags & TRACE_ITER_STACKTRACE))
                return;
 
-       __ftrace_trace_stack(tr, flags, skip, pc);
+       __ftrace_trace_stack(buffer, flags, skip, pc);
 }
 
-void __trace_stack(struct trace_array *tr,
-                  unsigned long flags,
-                  int skip, int pc)
+void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
+                  int pc)
 {
-       __ftrace_trace_stack(tr, flags, skip, pc);
+       __ftrace_trace_stack(tr->buffer, flags, skip, pc);
 }
 
-static void ftrace_trace_userstack(struct trace_array *tr,
-                                  unsigned long flags, int pc)
+void
+ftrace_trace_userstack(struct ring_buffer *buffer, 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;
@@ -1061,7 +1062,7 @@ static void ftrace_trace_userstack(struct trace_array *tr,
        if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
                return;
 
-       event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK,
+       event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
                                          sizeof(*entry), flags, pc);
        if (!event)
                return;
@@ -1075,9 +1076,8 @@ static void ftrace_trace_userstack(struct trace_array *tr,
        trace.entries           = entry->caller;
 
        save_stack_trace_user(&trace);
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+       if (!filter_check_discard(call, entry, buffer, event))
+               ring_buffer_unlock_commit(buffer, event);
 }
 
 #ifdef UNUSED
@@ -1087,6 +1087,8 @@ static void __trace_userstack(struct trace_array *tr, unsigned long flags)
 }
 #endif /* UNUSED */
 
+#endif /* CONFIG_STACKTRACE */
+
 static void
 ftrace_trace_special(void *__tr,
                     unsigned long arg1, unsigned long arg2, unsigned long arg3,
@@ -1094,9 +1096,10 @@ ftrace_trace_special(void *__tr,
 {
        struct ring_buffer_event *event;
        struct trace_array *tr = __tr;
+       struct ring_buffer *buffer = tr->buffer;
        struct special_entry *entry;
 
-       event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL,
+       event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL,
                                          sizeof(*entry), 0, pc);
        if (!event)
                return;
@@ -1104,7 +1107,7 @@ ftrace_trace_special(void *__tr,
        entry->arg1                     = arg1;
        entry->arg2                     = arg2;
        entry->arg3                     = arg3;
-       trace_buffer_unlock_commit(tr, event, 0, pc);
+       trace_buffer_unlock_commit(buffer, event, 0, pc);
 }
 
 void
@@ -1114,62 +1117,6 @@ __trace_special(void *__tr, void *__data,
        ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count());
 }
 
-void
-tracing_sched_switch_trace(struct trace_array *tr,
-                          struct task_struct *prev,
-                          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;
-
-       event = trace_buffer_lock_reserve(tr, TRACE_CTX,
-                                         sizeof(*entry), flags, pc);
-       if (!event)
-               return;
-       entry   = ring_buffer_event_data(event);
-       entry->prev_pid                 = prev->pid;
-       entry->prev_prio                = prev->prio;
-       entry->prev_state               = prev->state;
-       entry->next_pid                 = next->pid;
-       entry->next_prio                = next->prio;
-       entry->next_state               = next->state;
-       entry->next_cpu = task_cpu(next);
-
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               trace_buffer_unlock_commit(tr, event, flags, pc);
-}
-
-void
-tracing_sched_wakeup_trace(struct trace_array *tr,
-                          struct task_struct *wakee,
-                          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;
-
-       event = trace_buffer_lock_reserve(tr, TRACE_WAKE,
-                                         sizeof(*entry), flags, pc);
-       if (!event)
-               return;
-       entry   = ring_buffer_event_data(event);
-       entry->prev_pid                 = curr->pid;
-       entry->prev_prio                = curr->prio;
-       entry->prev_state               = curr->state;
-       entry->next_pid                 = wakee->pid;
-       entry->next_prio                = wakee->prio;
-       entry->next_state               = wakee->state;
-       entry->next_cpu                 = task_cpu(wakee);
-
-       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);
-}
-
 void
 ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
 {
@@ -1194,68 +1141,6 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
        local_irq_restore(flags);
 }
 
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-int trace_graph_entry(struct ftrace_graph_ent *trace)
-{
-       struct trace_array *tr = &global_trace;
-       struct trace_array_cpu *data;
-       unsigned long flags;
-       long disabled;
-       int ret;
-       int cpu;
-       int pc;
-
-       if (!ftrace_trace_task(current))
-               return 0;
-
-       if (!ftrace_graph_addr(trace->func))
-               return 0;
-
-       local_irq_save(flags);
-       cpu = raw_smp_processor_id();
-       data = tr->data[cpu];
-       disabled = atomic_inc_return(&data->disabled);
-       if (likely(disabled == 1)) {
-               pc = preempt_count();
-               ret = __trace_graph_entry(tr, trace, flags, pc);
-       } else {
-               ret = 0;
-       }
-       /* Only do the atomic if it is not already set */
-       if (!test_tsk_trace_graph(current))
-               set_tsk_trace_graph(current);
-
-       atomic_dec(&data->disabled);
-       local_irq_restore(flags);
-
-       return ret;
-}
-
-void trace_graph_return(struct ftrace_graph_ret *trace)
-{
-       struct trace_array *tr = &global_trace;
-       struct trace_array_cpu *data;
-       unsigned long flags;
-       long disabled;
-       int cpu;
-       int pc;
-
-       local_irq_save(flags);
-       cpu = raw_smp_processor_id();
-       data = tr->data[cpu];
-       disabled = atomic_inc_return(&data->disabled);
-       if (likely(disabled == 1)) {
-               pc = preempt_count();
-               __trace_graph_return(tr, trace, flags, pc);
-       }
-       if (!trace->depth)
-               clear_tsk_trace_graph(current);
-       atomic_dec(&data->disabled);
-       local_irq_restore(flags);
-}
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-
 /**
  * trace_vbprintk - write binary msg to tracing buffer
  *
@@ -1268,6 +1153,7 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
 
        struct ftrace_event_call *call = &event_bprint;
        struct ring_buffer_event *event;
+       struct ring_buffer *buffer;
        struct trace_array *tr = &global_trace;
        struct trace_array_cpu *data;
        struct bprint_entry *entry;
@@ -1300,7 +1186,9 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
                goto out_unlock;
 
        size = sizeof(*entry) + sizeof(u32) * len;
-       event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc);
+       buffer = tr->buffer;
+       event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
+                                         flags, pc);
        if (!event)
                goto out_unlock;
        entry = ring_buffer_event_data(event);
@@ -1308,8 +1196,8 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
        entry->fmt                      = fmt;
 
        memcpy(entry->buf, trace_buf, sizeof(u32) * len);
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               ring_buffer_unlock_commit(tr->buffer, event);
+       if (!filter_check_discard(call, entry, buffer, event))
+               ring_buffer_unlock_commit(buffer, event);
 
 out_unlock:
        __raw_spin_unlock(&trace_buf_lock);
@@ -1324,14 +1212,30 @@ out:
 }
 EXPORT_SYMBOL_GPL(trace_vbprintk);
 
-int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+int trace_array_printk(struct trace_array *tr,
+                      unsigned long ip, const char *fmt, ...)
+{
+       int ret;
+       va_list ap;
+
+       if (!(trace_flags & TRACE_ITER_PRINTK))
+               return 0;
+
+       va_start(ap, fmt);
+       ret = trace_array_vprintk(tr, ip, fmt, ap);
+       va_end(ap);
+       return ret;
+}
+
+int trace_array_vprintk(struct trace_array *tr,
+                       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 ring_buffer *buffer;
        struct trace_array_cpu *data;
        int cpu, len = 0, size, pc;
        struct print_entry *entry;
@@ -1359,7 +1263,9 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
        trace_buf[len] = 0;
 
        size = sizeof(*entry) + len + 1;
-       event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
+       buffer = tr->buffer;
+       event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size,
+                                         irq_flags, pc);
        if (!event)
                goto out_unlock;
        entry = ring_buffer_event_data(event);
@@ -1367,8 +1273,8 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
 
        memcpy(&entry->buf, trace_buf, len);
        entry->buf[len] = 0;
-       if (!filter_check_discard(call, entry, tr->buffer, event))
-               ring_buffer_unlock_commit(tr->buffer, event);
+       if (!filter_check_discard(call, entry, buffer, event))
+               ring_buffer_unlock_commit(buffer, event);
 
  out_unlock:
        __raw_spin_unlock(&trace_buf_lock);
@@ -1380,6 +1286,11 @@ int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
 
        return len;
 }
+
+int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+{
+       return trace_array_printk(&global_trace, ip, fmt, args);
+}
 EXPORT_SYMBOL_GPL(trace_vprintk);
 
 enum trace_file_type {
@@ -1519,6 +1430,37 @@ static void *s_next(struct seq_file *m, void *v, loff_t *pos)
        return ent;
 }
 
+static void tracing_iter_reset(struct trace_iterator *iter, int cpu)
+{
+       struct trace_array *tr = iter->tr;
+       struct ring_buffer_event *event;
+       struct ring_buffer_iter *buf_iter;
+       unsigned long entries = 0;
+       u64 ts;
+
+       tr->data[cpu]->skipped_entries = 0;
+
+       if (!iter->buffer_iter[cpu])
+               return;
+
+       buf_iter = iter->buffer_iter[cpu];
+       ring_buffer_iter_reset(buf_iter);
+
+       /*
+        * We could have the case with the max latency tracers
+        * that a reset never took place on a cpu. This is evident
+        * by the timestamp being before the start of the buffer.
+        */
+       while ((event = ring_buffer_iter_peek(buf_iter, &ts))) {
+               if (ts >= iter->tr->time_start)
+                       break;
+               entries++;
+               ring_buffer_read(buf_iter, NULL);
+       }
+
+       tr->data[cpu]->skipped_entries = entries;
+}
+
 /*
  * No necessary locking here. The worst thing which can
  * happen is loosing events consumed at the same time
@@ -1557,10 +1499,9 @@ static void *s_start(struct seq_file *m, loff_t *pos)
 
                if (cpu_file == TRACE_PIPE_ALL_CPU) {
                        for_each_tracing_cpu(cpu)
-                               ring_buffer_iter_reset(iter->buffer_iter[cpu]);
+                               tracing_iter_reset(iter, cpu);
                } else
-                       ring_buffer_iter_reset(iter->buffer_iter[cpu_file]);
-
+                       tracing_iter_reset(iter, cpu_file);
 
                ftrace_enable_cpu();
 
@@ -1609,16 +1550,32 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
        struct trace_array *tr = iter->tr;
        struct trace_array_cpu *data = tr->data[tr->cpu];
        struct tracer *type = current_trace;
-       unsigned long total;
-       unsigned long entries;
+       unsigned long entries = 0;
+       unsigned long total = 0;
+       unsigned long count;
        const char *name = "preemption";
+       int cpu;
 
        if (type)
                name = type->name;
 
-       entries = ring_buffer_entries(iter->tr->buffer);
-       total = entries +
-               ring_buffer_overruns(iter->tr->buffer);
+
+       for_each_tracing_cpu(cpu) {
+               count = ring_buffer_entries_cpu(tr->buffer, cpu);
+               /*
+                * If this buffer has skipped entries, then we hold all
+                * entries for the trace and we need to ignore the
+                * ones before the time stamp.
+                */
+               if (tr->data[cpu]->skipped_entries) {
+                       count -= tr->data[cpu]->skipped_entries;
+                       /* total is the same as the entries */
+                       total += count;
+               } else
+                       total += count +
+                               ring_buffer_overrun_cpu(tr->buffer, cpu);
+               entries += count;
+       }
 
        seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
                   name, UTS_RELEASE);
@@ -1660,7 +1617,7 @@ print_trace_header(struct seq_file *m, struct trace_iterator *iter)
                seq_puts(m, "\n#  => ended at:   ");
                seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
                trace_print_seq(m, &iter->seq);
-               seq_puts(m, "#\n");
+               seq_puts(m, "\n#\n");
        }
 
        seq_puts(m, "#\n");
@@ -1679,6 +1636,9 @@ static void test_cpu_buff_start(struct trace_iterator *iter)
        if (cpumask_test_cpu(iter->cpu, iter->started))
                return;
 
+       if (iter->tr->data[iter->cpu]->skipped_entries)
+               return;
+
        cpumask_set_cpu(iter->cpu, iter->started);
 
        /* Don't print started cpu buffer for the first entry of the trace */
@@ -1941,19 +1901,23 @@ __tracing_open(struct inode *inode, struct file *file)
        if (ring_buffer_overruns(iter->tr->buffer))
                iter->iter_flags |= TRACE_FILE_ANNOTATE;
 
+       /* stop the trace while dumping */
+       tracing_stop();
+
        if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
                for_each_tracing_cpu(cpu) {
 
                        iter->buffer_iter[cpu] =
                                ring_buffer_read_start(iter->tr->buffer, cpu);
+                       tracing_iter_reset(iter, cpu);
                }
        } else {
                cpu = iter->cpu_file;
                iter->buffer_iter[cpu] =
                                ring_buffer_read_start(iter->tr->buffer, cpu);
+               tracing_iter_reset(iter, cpu);
        }
 
-       /* TODO stop tracer */
        ret = seq_open(file, &tracer_seq_ops);
        if (ret < 0) {
                fail_ret = ERR_PTR(ret);
@@ -1963,9 +1927,6 @@ __tracing_open(struct inode *inode, struct file *file)
        m = file->private_data;
        m->private = iter;
 
-       /* stop the trace while dumping */
-       tracing_stop();
-
        mutex_unlock(&trace_types_lock);
 
        return iter;
@@ -1976,6 +1937,7 @@ __tracing_open(struct inode *inode, struct file *file)
                        ring_buffer_read_finish(iter->buffer_iter[cpu]);
        }
        free_cpumask_var(iter->started);
+       tracing_start();
  fail:
        mutex_unlock(&trace_types_lock);
        kfree(iter->trace);
@@ -2257,8 +2219,8 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
                len += 3; /* "no" and newline */
        }
 
-       /* +2 for \n and \0 */
-       buf = kmalloc(len + 2, GFP_KERNEL);
+       /* +1 for \0 */
+       buf = kmalloc(len + 1, GFP_KERNEL);
        if (!buf) {
                mutex_unlock(&trace_types_lock);
                return -ENOMEM;
@@ -2281,7 +2243,7 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
        }
        mutex_unlock(&trace_types_lock);
 
-       WARN_ON(r >= len + 2);
+       WARN_ON(r >= len + 1);
 
        r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
 
@@ -2292,23 +2254,23 @@ tracing_trace_options_read(struct file *filp, char __user *ubuf,
 /* Try to assign a tracer specific option */
 static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
 {
-       struct tracer_flags *trace_flags = trace->flags;
+       struct tracer_flags *tracer_flags = trace->flags;
        struct tracer_opt *opts = NULL;
        int ret = 0, i = 0;
        int len;
 
-       for (i = 0; trace_flags->opts[i].name; i++) {
-               opts = &trace_flags->opts[i];
+       for (i = 0; tracer_flags->opts[i].name; i++) {
+               opts = &tracer_flags->opts[i];
                len = strlen(opts->name);
 
                if (strncmp(cmp, opts->name, len) == 0) {
-                       ret = trace->set_flag(trace_flags->val,
+                       ret = trace->set_flag(tracer_flags->val,
                                opts->bit, !neg);
                        break;
                }
        }
        /* Not found */
-       if (!trace_flags->opts[i].name)
+       if (!tracer_flags->opts[i].name)
                return -EINVAL;
 
        /* Refused to handle */
@@ -2316,9 +2278,9 @@ static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
                return ret;
 
        if (neg)
-               trace_flags->val &= ~opts->bit;
+               tracer_flags->val &= ~opts->bit;
        else
-               trace_flags->val |= opts->bit;
+               tracer_flags->val |= opts->bit;
 
        return 0;
 }
@@ -2333,22 +2295,6 @@ static void set_tracer_flags(unsigned int mask, int enabled)
                trace_flags |= mask;
        else
                trace_flags &= ~mask;
-
-       if (mask == TRACE_ITER_GLOBAL_CLK) {
-               u64 (*func)(void);
-
-               if (enabled)
-                       func = trace_clock_global;
-               else
-                       func = trace_clock_local;
-
-               mutex_lock(&trace_types_lock);
-               ring_buffer_set_clock(global_trace.buffer, func);
-
-               if (max_tr.buffer)
-                       ring_buffer_set_clock(max_tr.buffer, func);
-               mutex_unlock(&trace_types_lock);
-       }
 }
 
 static ssize_t
@@ -3316,6 +3262,62 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
        return cnt;
 }
 
+static ssize_t tracing_clock_read(struct file *filp, char __user *ubuf,
+                                 size_t cnt, loff_t *ppos)
+{
+       char buf[64];
+       int bufiter = 0;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(trace_clocks); i++)
+               bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter,
+                       "%s%s%s%s", i ? " " : "",
+                       i == trace_clock_id ? "[" : "", trace_clocks[i].name,
+                       i == trace_clock_id ? "]" : "");
+       bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n");
+
+       return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter);
+}
+
+static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
+                                  size_t cnt, loff_t *fpos)
+{
+       char buf[64];
+       const char *clockstr;
+       int i;
+
+       if (cnt >= sizeof(buf))
+               return -EINVAL;
+
+       if (copy_from_user(&buf, ubuf, cnt))
+               return -EFAULT;
+
+       buf[cnt] = 0;
+
+       clockstr = strstrip(buf);
+
+       for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) {
+               if (strcmp(trace_clocks[i].name, clockstr) == 0)
+                       break;
+       }
+       if (i == ARRAY_SIZE(trace_clocks))
+               return -EINVAL;
+
+       trace_clock_id = i;
+
+       mutex_lock(&trace_types_lock);
+
+       ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func);
+       if (max_tr.buffer)
+               ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func);
+
+       mutex_unlock(&trace_types_lock);
+
+       *fpos += cnt;
+
+       return cnt;
+}
+
 static const struct file_operations tracing_max_lat_fops = {
        .open           = tracing_open_generic,
        .read           = tracing_max_lat_read,
@@ -3353,6 +3355,12 @@ static const struct file_operations tracing_mark_fops = {
        .write          = tracing_mark_write,
 };
 
+static const struct file_operations trace_clock_fops = {
+       .open           = tracing_open_generic,
+       .read           = tracing_clock_read,
+       .write          = tracing_clock_write,
+};
+
 struct ftrace_buffer_info {
        struct trace_array      *tr;
        void                    *spare;
@@ -3633,9 +3641,6 @@ tracing_stats_read(struct file *filp, char __user *ubuf,
        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);
@@ -4066,11 +4071,13 @@ static __init int tracer_init_debugfs(void)
        trace_create_file("current_tracer", 0644, d_tracer,
                        &global_trace, &set_tracer_fops);
 
+#ifdef CONFIG_TRACER_MAX_TRACE
        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);
+#endif
 
        trace_create_file("README", 0444, d_tracer,
                        NULL, &tracing_readme_fops);
@@ -4087,6 +4094,9 @@ static __init int tracer_init_debugfs(void)
        trace_create_file("saved_cmdlines", 0444, d_tracer,
                        NULL, &tracing_saved_cmdlines_fops);
 
+       trace_create_file("trace_clock", 0644, d_tracer, NULL,
+                         &trace_clock_fops);
+
 #ifdef CONFIG_DYNAMIC_FTRACE
        trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
                        &ftrace_update_tot_cnt, &tracing_dyn_info_fops);
@@ -4265,7 +4275,6 @@ void ftrace_dump(void)
 
 __init static int tracer_alloc_buffers(void)
 {
-       struct trace_array_cpu *data;
        int ring_buf_size;
        int i;
        int ret = -ENOMEM;
@@ -4315,7 +4324,7 @@ __init static int tracer_alloc_buffers(void)
 
        /* Allocate the first page for all buffers */
        for_each_tracing_cpu(i) {
-               data = global_trace.data[i] = &per_cpu(global_trace_cpu, i);
+               global_trace.data[i] = &per_cpu(global_trace_cpu, i);
                max_tr.data[i] = &per_cpu(max_data, i);
        }