From 637e7e864103a7a68c1ce43ada27dfc25c0d113f Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Fri, 11 Sep 2009 13:55:35 -0400 Subject: tracing: add lock depth to entries This patch adds the lock depth of the big kernel lock to the generic entry header. This way we can see the depth of the lock and help in removing the BKL. Example: # _------=> CPU# # / _-----=> irqs-off # | / _----=> need-resched # || / _---=> hardirq/softirq # ||| / _--=> preempt-depth # |||| /_--=> lock-depth # |||||/ delay # cmd pid |||||| time | caller # \ / |||||| \ | / -0 2.N..3 5902255250us+: lock_acquire: read rcu_read_lock -0 2.N..3 5902255253us+: lock_release: rcu_read_lock -0 2dN..3 5902255257us+: lock_acquire: xtime_lock -0 2dN..4 5902255259us : lock_acquire: clocksource_lock -0 2dN..4 5902255261us+: lock_release: clocksource_lock Signed-off-by: Steven Rostedt --- kernel/trace/trace.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace.c') diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 1a37da2e8534..3b918283cf94 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -886,6 +886,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, entry->preempt_count = pc & 0xff; entry->pid = (tsk) ? tsk->pid : 0; + entry->lock_depth = (tsk) ? tsk->lock_depth : 0; entry->flags = #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | @@ -1530,10 +1531,10 @@ static void print_lat_help_header(struct seq_file *m) seq_puts(m, "# | / _----=> need-resched \n"); seq_puts(m, "# || / _---=> hardirq/softirq \n"); seq_puts(m, "# ||| / _--=> preempt-depth \n"); - seq_puts(m, "# |||| / \n"); - seq_puts(m, "# ||||| delay \n"); - seq_puts(m, "# cmd pid ||||| time | caller \n"); - seq_puts(m, "# \\ / ||||| \\ | / \n"); + seq_puts(m, "# |||| /_--=> lock-depth \n"); + seq_puts(m, "# |||||/ delay \n"); + seq_puts(m, "# cmd pid |||||| time | caller \n"); + seq_puts(m, "# \\ / |||||| \\ | / \n"); } static void print_func_help_header(struct seq_file *m) -- cgit v1.2.3