tracing/fastboot: add a script to visualize the kernel boot process / time

When optimizing the kernel boot time, it's very valuable to visualize
what is going on at which time. In addition, with the fastboot asynchronous
initcall level, it's very valuable to see which initcall gets run where
and when.

This patch adds a script to turn a dmesg into a SVG graph (that can be
shown with tools such as InkScape, Gimp or Firefox) and a small change
to the initcall code to print the PID of the thread calling the initcall
(so that the script can work out the parallelism).

Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/init/main.c b/init/main.c
index ded1fae965ab..16abba05c826 100644
--- a/init/main.c
+++ b/init/main.c
@@ -711,7 +711,8 @@ int do_one_initcall(initcall_t fn)
         int result;
 
         if (initcall_debug) {
-                printk("calling  %pF\n", fn);
+                printk("calling  %pF", fn);
+                printk(" @ %i\n",  task_pid_nr(current));
                 t0 = ktime_get();
         }