GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-19 21:21:09 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

tracing: add lock depth to entries

Browse source 
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
 #     \   /      ||||||   \   |   /
   <idle>-0       2.N..3 5902255250us+: lock_acquire: read rcu_read_lock
   <idle>-0       2.N..3 5902255253us+: lock_release: rcu_read_lock
   <idle>-0       2dN..3 5902255257us+: lock_acquire: xtime_lock
   <idle>-0       2dN..4 5902255259us : lock_acquire: clocksource_lock
   <idle>-0       2dN..4 5902255261us+: lock_release: clocksource_lock

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
This commit is contained in:
Steven Rostedt 2009-09-11 13:55:35 -04:00 • committed by Steven Rostedt
parent 48659d3119
commit 637e7e8641
5 changed files with 31 additions and 10 deletions
Download patch file Download diff file Expand all files Collapse all files

10
kernel/trace/trace_output.c
View file

@ -465,6 +465,7 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
{
int hardirq, softirq;
char comm[TASK_COMM_LEN];
int ret;
trace_find_cmdline(entry->pid, comm);
hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
@ -481,9 +482,16 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
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, ".");
return trace_seq_putc(s, '.');
}
static unsigned long preempt_mark_thresh = 100;