{
unsigned pid, idx;
- if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
+ /* treat recording of idle task as a success */
+ if (!tsk->pid)
+ return 1;
+
+ if (unlikely(tsk->pid > PID_MAX_DEFAULT))
return 0;
/*
static int trace_save_tgid(struct task_struct *tsk)
{
- if (unlikely(!tgid_map || !tsk->pid || tsk->pid > PID_MAX_DEFAULT))
+ /* treat recording of idle task as a success */
+ if (!tsk->pid)
+ return 1;
+
+ if (unlikely(!tgid_map || tsk->pid > PID_MAX_DEFAULT))
return 0;
tgid_map[tsk->pid] = tsk->tgid;
*/
void tracing_record_taskinfo(struct task_struct *task, int flags)
{
+ bool done;
+
if (tracing_record_taskinfo_skip(flags))
return;
- if ((flags & TRACE_RECORD_CMDLINE) && !trace_save_cmdline(task))
- return;
- if ((flags & TRACE_RECORD_TGID) && !trace_save_tgid(task))
+
+ /*
+ * Record as much task information as possible. If some fail, continue
+ * to try to record the others.
+ */
+ done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task);
+ done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task);
+
+ /* If recording any information failed, retry again soon. */
+ if (!done)
return;
__this_cpu_write(trace_taskinfo_save, false);
void tracing_record_taskinfo_sched_switch(struct task_struct *prev,
struct task_struct *next, int flags)
{
+ bool done;
+
if (tracing_record_taskinfo_skip(flags))
return;
- if ((flags & TRACE_RECORD_CMDLINE) &&
- (!trace_save_cmdline(prev) || !trace_save_cmdline(next)))
- return;
+ /*
+ * Record as much task information as possible. If some fail, continue
+ * to try to record the others.
+ */
+ done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev);
+ done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next);
+ done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev);
+ done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next);
- if ((flags & TRACE_RECORD_TGID) &&
- (!trace_save_tgid(prev) || !trace_save_tgid(next)))
+ /* If recording any information failed, retry again soon. */
+ if (!done)
return;
__this_cpu_write(trace_taskinfo_save, false);
unsigned int flags)
{
bool tgid = flags & TRACE_ITER_RECORD_TGID;
-
- seq_printf(m, "# %s _-----=> irqs-off\n", tgid ? " " : "");
- seq_printf(m, "# %s / _----=> need-resched\n", tgid ? " " : "");
- seq_printf(m, "# %s| / _---=> hardirq/softirq\n", tgid ? " " : "");
- seq_printf(m, "# %s|| / _--=> preempt-depth\n", tgid ? " " : "");
- seq_printf(m, "# %s||| / delay\n", tgid ? " " : "");
- seq_printf(m, "# TASK-PID CPU#%s|||| TIMESTAMP FUNCTION\n", tgid ? " TGID " : "");
- seq_printf(m, "# | | | %s|||| | |\n", tgid ? " | " : "");
+ const char tgid_space[] = " ";
+ const char space[] = " ";
+
+ seq_printf(m, "# %s _-----=> irqs-off\n",
+ tgid ? tgid_space : space);
+ seq_printf(m, "# %s / _----=> need-resched\n",
+ tgid ? tgid_space : space);
+ seq_printf(m, "# %s| / _---=> hardirq/softirq\n",
+ tgid ? tgid_space : space);
+ seq_printf(m, "# %s|| / _--=> preempt-depth\n",
+ tgid ? tgid_space : space);
+ seq_printf(m, "# %s||| / delay\n",
+ tgid ? tgid_space : space);
+ seq_printf(m, "# TASK-PID CPU#%s|||| TIMESTAMP FUNCTION\n",
+ tgid ? " TGID " : space);
+ seq_printf(m, "# | | | %s|||| | |\n",
+ tgid ? " | " : space);
}
void
.llseek = generic_file_llseek,
};
+static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ int *ptr = v;
+
+ if (*pos || m->count)
+ ptr++;
+
+ (*pos)++;
+
+ for (; ptr <= &tgid_map[PID_MAX_DEFAULT]; ptr++) {
+ if (trace_find_tgid(*ptr))
+ return ptr;
+ }
+
+ return NULL;
+}
+
+static void *saved_tgids_start(struct seq_file *m, loff_t *pos)
+{
+ void *v;
+ loff_t l = 0;
+
+ if (!tgid_map)
+ return NULL;
+
+ v = &tgid_map[0];
+ while (l <= *pos) {
+ v = saved_tgids_next(m, v, &l);
+ if (!v)
+ return NULL;
+ }
+
+ return v;
+}
+
+static void saved_tgids_stop(struct seq_file *m, void *v)
+{
+}
+
+static int saved_tgids_show(struct seq_file *m, void *v)
+{
+ int pid = (int *)v - tgid_map;
+
+ seq_printf(m, "%d %d\n", pid, trace_find_tgid(pid));
+ return 0;
+}
+
+static const struct seq_operations tracing_saved_tgids_seq_ops = {
+ .start = saved_tgids_start,
+ .stop = saved_tgids_stop,
+ .next = saved_tgids_next,
+ .show = saved_tgids_show,
+};
+
+static int tracing_saved_tgids_open(struct inode *inode, struct file *filp)
+{
+ if (tracing_disabled)
+ return -ENODEV;
+
+ return seq_open(filp, &tracing_saved_tgids_seq_ops);
+}
+
+
+static const struct file_operations tracing_saved_tgids_fops = {
+ .open = tracing_saved_tgids_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos)
{
unsigned int *ptr = v;
}
kfree(tr->topts);
+ free_cpumask_var(tr->tracing_cpumask);
kfree(tr->name);
kfree(tr);
trace_create_file("saved_cmdlines_size", 0644, d_tracer,
NULL, &tracing_saved_cmdlines_size_fops);
+ trace_create_file("saved_tgids", 0444, d_tracer,
+ NULL, &tracing_saved_tgids_fops);
+
trace_eval_init();
trace_create_eval_file(d_tracer);