Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
[safe/jmp/linux-2.6] / kernel / trace / trace_functions_graph.c
index d2249ab..45e6c01 100644 (file)
@@ -52,7 +52,7 @@ static struct tracer_flags tracer_flags = {
        .opts = trace_opts
 };
 
-/* pid on the last trace processed */
+static struct trace_array *graph_array;
 
 
 /* Add a function return address to the trace stack on thread info.*/
@@ -124,7 +124,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
        if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
                ftrace_graph_stop();
                WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
-                    "  from func %pF return to %lx\n",
+                    "  from func %ps return to %lx\n",
                     current->ret_stack[index].fp,
                     frame_pointer,
                     (void *)current->ret_stack[index].func,
@@ -166,10 +166,123 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
        return ret;
 }
 
+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 ring_buffer *buffer = tr->buffer;
+       struct ftrace_graph_ent_entry *entry;
+
+       if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+               return 0;
+
+       event = trace_buffer_lock_reserve(buffer, 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(buffer, call, entry, event))
+               ring_buffer_unlock_commit(buffer, event);
+
+       return 1;
+}
+
+int trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+       struct trace_array *tr = graph_array;
+       struct trace_array_cpu *data;
+       unsigned long flags;
+       long disabled;
+       int ret;
+       int cpu;
+       int pc;
+
+       if (unlikely(!tr))
+               return 0;
+
+       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;
+}
+
+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 ring_buffer *buffer = tr->buffer;
+       struct ftrace_graph_ret_entry *entry;
+
+       if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+               return;
+
+       event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
+                                         sizeof(*entry), flags, pc);
+       if (!event)
+               return;
+       entry   = ring_buffer_event_data(event);
+       entry->ret                              = *trace;
+       if (!filter_current_check_discard(buffer, call, entry, event))
+               ring_buffer_unlock_commit(buffer, event);
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
+{
+       struct trace_array *tr = graph_array;
+       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);
+}
+
 static int graph_trace_init(struct trace_array *tr)
 {
-       int ret = register_ftrace_graph(&trace_graph_return,
-                                       &trace_graph_entry);
+       int ret;
+
+       graph_array = tr;
+       ret = register_ftrace_graph(&trace_graph_return,
+                                   &trace_graph_entry);
        if (ret)
                return ret;
        tracing_start_cmdline_record();
@@ -177,49 +290,30 @@ static int graph_trace_init(struct trace_array *tr)
        return 0;
 }
 
+void set_graph_array(struct trace_array *tr)
+{
+       graph_array = tr;
+}
+
 static void graph_trace_reset(struct trace_array *tr)
 {
        tracing_stop_cmdline_record();
        unregister_ftrace_graph();
 }
 
-static inline int log10_cpu(int nb)
-{
-       if (nb / 100)
-               return 3;
-       if (nb / 10)
-               return 2;
-       return 1;
-}
+static int max_bytes_for_cpu;
 
 static enum print_line_t
 print_graph_cpu(struct trace_seq *s, int cpu)
 {
-       int i;
        int ret;
-       int log10_this = log10_cpu(cpu);
-       int log10_all = log10_cpu(cpumask_weight(cpu_online_mask));
-
 
        /*
         * Start with a space character - to make it stand out
         * to the right a bit when trace output is pasted into
         * email:
         */
-       ret = trace_seq_printf(s, " ");
-
-       /*
-        * Tricky - we space the CPU field according to the max
-        * number of online CPUs. On a 2-cpu system it would take
-        * a maximum of 1 digit - on a 128 cpu system it would
-        * take up to 3 digits:
-        */
-       for (i = 0; i < log10_all - log10_this; i++) {
-               ret = trace_seq_printf(s, " ");
-               if (!ret)
-                       return TRACE_TYPE_PARTIAL_LINE;
-       }
-       ret = trace_seq_printf(s, "%d) ", cpu);
+       ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
        if (!ret)
                return TRACE_TYPE_PARTIAL_LINE;
 
@@ -270,6 +364,15 @@ print_graph_proc(struct trace_seq *s, pid_t pid)
 }
 
 
+static enum print_line_t
+print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+{
+       if (!trace_seq_putc(s, ' '))
+               return 0;
+
+       return trace_print_lat_fmt(s, entry);
+}
+
 /* If the pid changed since the last trace, output this event */
 static enum print_line_t
 verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
@@ -427,6 +530,7 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
                if (ret == TRACE_TYPE_PARTIAL_LINE)
                        return TRACE_TYPE_PARTIAL_LINE;
        }
+
        /* Proc */
        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
                ret = print_graph_proc(s, pid);
@@ -565,11 +669,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
                        return TRACE_TYPE_PARTIAL_LINE;
        }
 
-       ret = seq_print_ip_sym(s, call->func, 0);
-       if (!ret)
-               return TRACE_TYPE_PARTIAL_LINE;
-
-       ret = trace_seq_printf(s, "();\n");
+       ret = trace_seq_printf(s, "%ps();\n", (void *)call->func);
        if (!ret)
                return TRACE_TYPE_PARTIAL_LINE;
 
@@ -612,11 +712,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
                        return TRACE_TYPE_PARTIAL_LINE;
        }
 
-       ret = seq_print_ip_sym(s, call->func, 0);
-       if (!ret)
-               return TRACE_TYPE_PARTIAL_LINE;
-
-       ret = trace_seq_printf(s, "() {\n");
+       ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func);
        if (!ret)
                return TRACE_TYPE_PARTIAL_LINE;
 
@@ -672,6 +768,13 @@ print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
                        return TRACE_TYPE_PARTIAL_LINE;
        }
 
+       /* Latency format */
+       if (trace_flags & TRACE_ITER_LATENCY_FMT) {
+               ret = print_graph_lat_fmt(s, ent);
+               if (ret == TRACE_TYPE_PARTIAL_LINE)
+                       return TRACE_TYPE_PARTIAL_LINE;
+       }
+
        return 0;
 }
 
@@ -843,9 +946,16 @@ print_graph_function(struct trace_iterator *iter)
 
        switch (entry->type) {
        case TRACE_GRAPH_ENT: {
-               struct ftrace_graph_ent_entry *field;
+               /*
+                * print_graph_entry() may consume the current event,
+                * thus @field may become invalid, so we need to save it.
+                * sizeof(struct ftrace_graph_ent_entry) is very small,
+                * it can be safely saved at the stack.
+                */
+               struct ftrace_graph_ent_entry *field, saved;
                trace_assign_type(field, entry);
-               return print_graph_entry(field, s, iter);
+               saved = *field;
+               return print_graph_entry(&saved, s, iter);
        }
        case TRACE_GRAPH_RET: {
                struct ftrace_graph_ret_entry *field;
@@ -859,28 +969,59 @@ print_graph_function(struct trace_iterator *iter)
        return TRACE_TYPE_HANDLED;
 }
 
+static void print_lat_header(struct seq_file *s)
+{
+       static const char spaces[] = "                " /* 16 spaces */
+               "    "                                  /* 4 spaces */
+               "                 ";                    /* 17 spaces */
+       int size = 0;
+
+       if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
+               size += 16;
+       if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
+               size += 4;
+       if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
+               size += 17;
+
+       seq_printf(s, "#%.*s  _-----=> irqs-off        \n", size, spaces);
+       seq_printf(s, "#%.*s / _----=> need-resched    \n", size, spaces);
+       seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
+       seq_printf(s, "#%.*s|| / _--=> preempt-depth   \n", size, spaces);
+       seq_printf(s, "#%.*s||| / _-=> lock-depth      \n", size, spaces);
+       seq_printf(s, "#%.*s|||| /                     \n", size, spaces);
+}
+
 static void print_graph_headers(struct seq_file *s)
 {
+       int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
+
+       if (lat)
+               print_lat_header(s);
+
        /* 1st line */
-       seq_printf(s, "# ");
+       seq_printf(s, "#");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
                seq_printf(s, "     TIME       ");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
-               seq_printf(s, "CPU");
+               seq_printf(s, " CPU");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
-               seq_printf(s, "  TASK/PID      ");
+               seq_printf(s, "  TASK/PID       ");
+       if (lat)
+               seq_printf(s, "|||||");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
                seq_printf(s, "  DURATION   ");
        seq_printf(s, "               FUNCTION CALLS\n");
 
        /* 2nd line */
-       seq_printf(s, "# ");
+       seq_printf(s, "#");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_ABS_TIME)
                seq_printf(s, "      |         ");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU)
-               seq_printf(s, "|  ");
+               seq_printf(s, " |  ");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC)
-               seq_printf(s, "  |    |        ");
+               seq_printf(s, "   |    |        ");
+       if (lat)
+               seq_printf(s, "|||||");
        if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION)
                seq_printf(s, "   |   |      ");
        seq_printf(s, "               |   |   |   |\n");
@@ -927,6 +1068,8 @@ static struct tracer graph_trace __read_mostly = {
 
 static __init int init_graph_trace(void)
 {
+       max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
        return register_tracer(&graph_trace);
 }