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_functions_graph.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'kernel/trace/trace_functions_graph.c') diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index ee791a9650c..48af4937438 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -368,6 +368,7 @@ static enum print_line_t print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry) { int hardirq, softirq; + int ret; hardirq = entry->flags & TRACE_FLAG_HARDIRQ; softirq = entry->flags & TRACE_FLAG_SOFTIRQ; @@ -382,6 +383,13 @@ print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry) hardirq ? 'h' : softirq ? 's' : '.')) return 0; + if (entry->lock_depth < 0) + ret = trace_seq_putc(s, '.'); + else + ret = trace_seq_printf(s, "%d", entry->lock_depth); + if (!ret) + return 0; + if (entry->preempt_count) return trace_seq_printf(s, "%x", entry->preempt_count); return trace_seq_puts(s, "."); @@ -1001,8 +1009,8 @@ static void print_lat_header(struct seq_file *s) seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces); seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces); seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces); - seq_printf(s, "#%.*s||| / \n", size, spaces); - seq_printf(s, "#%.*s|||| \n", size, spaces); + seq_printf(s, "#%.*s||| / _-=> lock-depth \n", size, spaces); + seq_printf(s, "#%.*s|||| / \n", size, spaces); } static void print_graph_headers(struct seq_file *s) @@ -1021,7 +1029,7 @@ static void print_graph_headers(struct seq_file *s) if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) seq_printf(s, " TASK/PID "); if (lat) - seq_printf(s, "||||"); + seq_printf(s, "|||||"); if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) seq_printf(s, " DURATION "); seq_printf(s, " FUNCTION CALLS\n"); @@ -1035,7 +1043,7 @@ static void print_graph_headers(struct seq_file *s) if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) seq_printf(s, " | | "); if (lat) - seq_printf(s, "||||"); + seq_printf(s, "|||||"); if (tracer_flags.val & TRACE_GRAPH_PRINT_DURATION) seq_printf(s, " | | "); seq_printf(s, " | | | |\n"); -- cgit v1.2.3