diff options
| author | Steven Rostedt <srostedt@redhat.com> | 2009-09-03 19:13:05 -0400 |
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2009-09-04 19:22:41 -0400 |
| commit | e8165dbb03ed04d798163ee512074b9a9466a9c8 (patch) | |
| tree | a9e640253a8ce14bada6a83fe1d85ecd74968695 /ipc/msg.c | |
| parent | 659372d3e42a3e17a2e042d38a8bcdb94bfbe797 (diff) | |
tracing: report error in trace if we fail to swap latency buffer
The irqsoff tracer will fail to swap the cpu buffer with the max
buffer if it preempts a commit. Instead of ignoring this, this patch
makes the tracer report it if the last max latency failed due to preempting
a current commit.
The output of the latency tracer will look like this:
# tracer: irqsoff
#
# irqsoff latency trace v1.1.5 on 2.6.31-rc5
# --------------------------------------------------------------------
# latency: 112 us, #1/1, CPU#1 | (M:preempt VP:0, KP:0, SP:0 HP:0 #P:4)
# -----------------
# | task: -4281 (uid:0 nice:0 policy:0 rt_prio:0)
# -----------------
# => started at: save_args
# => ended at: __do_softirq
#
#
# _------=> CPU#
# / _-----=> irqs-off
# | / _----=> need-resched
# || / _---=> hardirq/softirq
# ||| / _--=> preempt-depth
# |||| /
# ||||| delay
# cmd pid ||||| time | caller
# \ / ||||| \ | /
bash-4281 1d.s6 265us : update_max_tr_single: Failed to swap buffers due to commit in progress
Note the latency time and the functions that disabled the irqs or preemption
will still be listed.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'ipc/msg.c')
0 files changed, 0 insertions, 0 deletions