1 files changed, 109 insertions, 49 deletions

diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index d0a5e50eeff2..3ccebde28482 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -13,101 +13,161 @@
 #include "trace.h"
 
 static struct trace_array *boot_trace;
-static int trace_boot_enabled;
+static bool pre_initcalls_finished;
 
-
-/* Should be started after do_pre_smp_initcalls() in init/main.c */
+/* Tells the boot tracer that the pre_smp_initcalls are finished.
+ * So we are ready .
+ * It doesn't enable sched events tracing however.
+ * You have to call enable_boot_trace to do so.
+ */
 void start_boot_trace(void)
 {
-        trace_boot_enabled = 1;
+        pre_initcalls_finished = true;
 }
 
-void stop_boot_trace(void)
+void enable_boot_trace(void)
 {
-        trace_boot_enabled = 0;
+        if (pre_initcalls_finished)
+                tracing_start_sched_switch_record();
 }
 
-void reset_boot_trace(struct trace_array *tr)
+void disable_boot_trace(void)
 {
-        stop_boot_trace();
+        if (pre_initcalls_finished)
+                tracing_stop_sched_switch_record();
 }
 
-static void boot_trace_init(struct trace_array *tr)
+static int boot_trace_init(struct trace_array *tr)
 {
         int cpu;
         boot_trace = tr;
 
-        trace_boot_enabled = 0;
-
         for_each_cpu_mask(cpu, cpu_possible_map)
                 tracing_reset(tr, cpu);
+
+        tracing_sched_switch_assign_trace(tr);
+        return 0;
 }
 
-static void boot_trace_ctrl_update(struct trace_array *tr)
+static enum print_line_t
+initcall_call_print_line(struct trace_iterator *iter)
 {
-        if (tr->ctrl)
-                start_boot_trace();
+        struct trace_entry *entry = iter->ent;
+        struct trace_seq *s = &iter->seq;
+        struct trace_boot_call *field;
+        struct boot_trace_call *call;
+        u64 ts;
+        unsigned long nsec_rem;
+        int ret;
+
+        trace_assign_type(field, entry);
+        call = &field->boot_call;
+        ts = iter->ts;
+        nsec_rem = do_div(ts, 1000000000);
+
+        ret = trace_seq_printf(s, "[%5ld.%09ld] calling  %s @ %i\n",
+                        (unsigned long)ts, nsec_rem, call->func, call->caller);
+
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
         else
-                stop_boot_trace();
+                return TRACE_TYPE_HANDLED;
 }
 
-static enum print_line_t initcall_print_line(struct trace_iterator *iter)
+static enum print_line_t
+initcall_ret_print_line(struct trace_iterator *iter)
 {
-        int ret;
         struct trace_entry *entry = iter->ent;
-        struct trace_boot *field = (struct trace_boot *)entry;
-        struct boot_trace *it = &field->initcall;
         struct trace_seq *s = &iter->seq;
-        struct timespec calltime = ktime_to_timespec(it->calltime);
-        struct timespec rettime = ktime_to_timespec(it->rettime);
-
-        if (entry->type == TRACE_BOOT) {
-                ret = trace_seq_printf(s, "[%5ld.%09ld] calling  %s @ %i\n",
-                                          calltime.tv_sec,
-                                          calltime.tv_nsec,
-                                          it->func, it->caller);
-                if (!ret)
-                        return TRACE_TYPE_PARTIAL_LINE;
-
-                ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s "
-                                          "returned %d after %lld msecs\n",
-                                          rettime.tv_sec,
-                                          rettime.tv_nsec,
-                                          it->func, it->result, it->duration);
-
-                if (!ret)
-                        return TRACE_TYPE_PARTIAL_LINE;
+        struct trace_boot_ret *field;
+        struct boot_trace_ret *init_ret;
+        u64 ts;
+        unsigned long nsec_rem;
+        int ret;
+
+        trace_assign_type(field, entry);
+        init_ret = &field->boot_ret;
+        ts = iter->ts;
+        nsec_rem = do_div(ts, 1000000000);
+
+        ret = trace_seq_printf(s, "[%5ld.%09ld] initcall %s "
+                        "returned %d after %llu msecs\n",
+                        (unsigned long) ts,
+                        nsec_rem,
+                        init_ret->func, init_ret->result, init_ret->duration);
+
+        if (!ret)
+                return TRACE_TYPE_PARTIAL_LINE;
+        else
                 return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t initcall_print_line(struct trace_iterator *iter)
+{
+        struct trace_entry *entry = iter->ent;
+
+        switch (entry->type) {
+        case TRACE_BOOT_CALL:
+                return initcall_call_print_line(iter);
+        case TRACE_BOOT_RET:
+                return initcall_ret_print_line(iter);
+        default:
+                return TRACE_TYPE_UNHANDLED;
         }
-        return TRACE_TYPE_UNHANDLED;
 }
 
 struct tracer boot_tracer __read_mostly =
 {
         .name           = "initcall",
         .init           = boot_trace_init,
-        .reset          = reset_boot_trace,
-        .ctrl_update    = boot_trace_ctrl_update,
+        .reset          = tracing_reset_online_cpus,
         .print_line     = initcall_print_line,
 };
 
-void trace_boot(struct boot_trace *it, initcall_t fn)
+void trace_boot_call(struct boot_trace_call *bt, initcall_t fn)
 {
         struct ring_buffer_event *event;
-        struct trace_boot *entry;
-        struct trace_array_cpu *data;
+        struct trace_boot_call *entry;
         unsigned long irq_flags;
         struct trace_array *tr = boot_trace;
 
-        if (!trace_boot_enabled)
+        if (!pre_initcalls_finished)
                 return;
 
         /* Get its name now since this function could
          * disappear because it is in the .init section.
          */
-        sprint_symbol(it->func, (unsigned long)fn);
+        sprint_symbol(bt->func, (unsigned long)fn);
+        preempt_disable();
+
+        event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
+                                         &irq_flags);
+        if (!event)
+                goto out;
+        entry   = ring_buffer_event_data(event);
+        tracing_generic_entry_update(&entry->ent, 0, 0);
+        entry->ent.type = TRACE_BOOT_CALL;
+        entry->boot_call = *bt;
+        ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+
+        trace_wake_up();
+
+ out:
+        preempt_enable();
+}
+
+void trace_boot_ret(struct boot_trace_ret *bt, initcall_t fn)
+{
+        struct ring_buffer_event *event;
+        struct trace_boot_ret *entry;
+        unsigned long irq_flags;
+        struct trace_array *tr = boot_trace;
+
+        if (!pre_initcalls_finished)
+                return;
+
+        sprint_symbol(bt->func, (unsigned long)fn);
         preempt_disable();
-        data = tr->data[smp_processor_id()];
 
         event = ring_buffer_lock_reserve(tr->buffer, sizeof(*entry),
                                          &irq_flags);
@@ -115,8 +175,8 @@ void trace_boot(struct boot_trace *it, initcall_t fn)
                 goto out;
         entry   = ring_buffer_event_data(event);
         tracing_generic_entry_update(&entry->ent, 0, 0);
-        entry->ent.type = TRACE_BOOT;
-        entry->initcall = *it;
+        entry->ent.type = TRACE_BOOT_RET;
+        entry->boot_ret = *bt;
         ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
 
         trace_wake_up();