powerpc: Add last sysfs file and dump of ftrace buffer to oops printout
authorAnton Blanchard <anton@samba.org>
Sun, 7 Feb 2010 14:44:16 +0000 (14:44 +0000)
committerBenjamin Herrenschmidt <benh@kernel.crashing.org>
Tue, 9 Feb 2010 02:56:06 +0000 (13:56 +1100)
commit66fcb1059deeae072c1bf1536a8e2613028bce3e
tree99390b75ec2b292a97fcf880e1f6752d27eb80fc
parentb926a88a7b77bc27c0e7f67166f34b854fe21ccc
powerpc: Add last sysfs file and dump of ftrace buffer to oops printout

Add printout of last accessed sysfs file, added to x86 in
ae87221d3ce49d9de1e43756da834fd0bf05a2ad (sysfs: crash debugging)

Also add the notify_die hook that allows us to print out the ftrace
buffer on oops. This is useful in conjunction with ftrace function_graph:

Oops: Kernel access of bad area, sig: 11 [#1]
SMP NR_CPUS=128 NUMA pSeries
last sysfs file: /sys/class/net/tunl0/type
Dumping ftrace buffer:

...

  0)               |                .sysrq_handle_crash() {
  0)   0.476 us    |                  .hash_page();
  0)   0.488 us    |                  .xmon_fault_handler();
  0)               |                  .bad_page_fault() {
  0)               |                    .search_exception_tables() {
  0)   0.590 us    |                      .search_module_extables();
  0)   2.546 us    |                    }
  0)               |                    .printk() {
  0)               |                      .vprintk() {
  0)   0.488 us    |                        ._raw_spin_lock();
  0)   0.572 us    |                        .emit_log_char();

Showing the function graph of a sysrq-c crash.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
arch/powerpc/kernel/traps.c