tracing: Make the space reserved for the pid wider

For 64bit CONFIG_BASE_SMALL=0 systems PID_MAX_LIMIT is set by default to
4194304. During boot the kernel sets a new value based on number of CPUs
but no lower than 32768. It is 1024 per CPU so with 128 CPUs the default
becomes 131072 which needs six digits.
This value can be increased during run time but must not exceed the
initial upper limit.

Systemd sometime after v241 sets it to the upper limit during boot. The
result is that when the pid exceeds five digits, the trace output is a
little hard to read because it is no longer properly padded (same like
on big iron with 98+ CPUs).

Increase the pid padding to seven digits.

Link: https://lkml.kernel.org/r/20200904082331.dcdkrr3bkn3e4qlg@linutronix.de

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit is contained in:
Sebastian Andrzej Siewior
2020-09-04 10:23:31 +02:00
committed by Steven Rostedt (VMware)
parent 478ece9573
commit 795d6379a4
2 changed files with 25 additions and 25 deletions
+6 -6
View File
@@ -497,7 +497,7 @@ lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(s, "%8.8s-%-5d %3d",
trace_seq_printf(s, "%8.8s-%-7d %3d",
comm, entry->pid, cpu);
return trace_print_lat_fmt(s, entry);
@@ -588,15 +588,15 @@ int trace_print_context(struct trace_iterator *iter)
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid);
trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid);
if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
unsigned int tgid = trace_find_tgid(entry->pid);
if (!tgid)
trace_seq_printf(s, "(-----) ");
trace_seq_printf(s, "(-------) ");
else
trace_seq_printf(s, "(%5d) ", tgid);
trace_seq_printf(s, "(%7d) ", tgid);
}
trace_seq_printf(s, "[%03d] ", iter->cpu);
@@ -636,7 +636,7 @@ int trace_print_lat_context(struct trace_iterator *iter)
trace_find_cmdline(entry->pid, comm);
trace_seq_printf(
s, "%16s %5d %3d %d %08x %08lx ",
s, "%16s %7d %3d %d %08x %08lx ",
comm, entry->pid, iter->cpu, entry->flags,
entry->preempt_count, iter->idx);
} else {
@@ -917,7 +917,7 @@ static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
S = task_index_to_char(field->prev_state);
trace_find_cmdline(field->next_pid, comm);
trace_seq_printf(&iter->seq,
" %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
" %7d:%3d:%c %s [%03d] %7d:%3d:%c %s\n",
field->prev_pid,
field->prev_prio,
S, delim,