Commit 11e84acc authored by Frederic Weisbecker's avatar Frederic Weisbecker Committed by Ingo Molnar

tracing/function-graph-tracer: display unified style cmdline and pid

Impact: extend function-graph output: let one know which thread called a function

This patch implements a helper function to print the couple cmdline/pid.
Its output is provided during task switching and on each row if the new
"funcgraph-proc" defualt-off option is set through trace_options file.

The output is center aligned and never exceeds 14 characters. The cmdline
is truncated over 7 chars.
But note that if the pid exceeds 6 characters, the column will overflow (but
the situation is abnormal).
Signed-off-by: default avatarFrederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
parent 62679efe
......@@ -19,6 +19,7 @@
#define TRACE_GRAPH_PRINT_OVERRUN 0x1
#define TRACE_GRAPH_PRINT_CPU 0x2
#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
#define TRACE_GRAPH_PRINT_PROC 0x8
static struct tracer_opt trace_opts[] = {
/* Display overruns ? */
......@@ -27,11 +28,13 @@ static struct tracer_opt trace_opts[] = {
{ TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) },
/* Display Overhead ? */
{ TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) },
/* Display proc name/pid */
{ TRACER_OPT(funcgraph-proc, TRACE_GRAPH_PRINT_PROC) },
{ } /* Empty entry */
};
static struct tracer_flags tracer_flags = {
/* Don't display overruns by default */
/* Don't display overruns and proc by default */
.val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD,
.opts = trace_opts
};
......@@ -104,23 +107,63 @@ print_graph_cpu(struct trace_seq *s, int cpu)
return TRACE_TYPE_HANDLED;
}
#define TRACE_GRAPH_PROCINFO_LENGTH 14
static enum print_line_t
print_graph_proc(struct trace_seq *s, pid_t pid)
{
int i;
int ret;
int len;
char comm[8];
int spaces = 0;
/* sign + log10(MAX_INT) + '\0' */
char pid_str[11];
strncpy(comm, trace_find_cmdline(pid), 7);
comm[7] = '\0';
sprintf(pid_str, "%d", pid);
/* 1 stands for the "-" character */
len = strlen(comm) + strlen(pid_str) + 1;
if (len < TRACE_GRAPH_PROCINFO_LENGTH)
spaces = TRACE_GRAPH_PROCINFO_LENGTH - len;
/* First spaces to align center */
for (i = 0; i < spaces / 2; i++) {
ret = trace_seq_printf(s, " ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
ret = trace_seq_printf(s, "%s-%s", comm, pid_str);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
/* Last spaces to align center */
for (i = 0; i < spaces - (spaces / 2); i++) {
ret = trace_seq_printf(s, " ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
return TRACE_TYPE_HANDLED;
}
/* If the pid changed since the last trace, output this event */
static int verif_pid(struct trace_seq *s, pid_t pid, int cpu)
static enum print_line_t
verif_pid(struct trace_seq *s, pid_t pid, int cpu)
{
char *comm, *prev_comm;
pid_t prev_pid;
int ret;
if (last_pid[cpu] != -1 && last_pid[cpu] == pid)
return 1;
return TRACE_TYPE_HANDLED;
prev_pid = last_pid[cpu];
last_pid[cpu] = pid;
comm = trace_find_cmdline(pid);
prev_comm = trace_find_cmdline(prev_pid);
/*
* Context-switch trace line:
......@@ -130,11 +173,31 @@ static int verif_pid(struct trace_seq *s, pid_t pid, int cpu)
*/
ret = trace_seq_printf(s,
" ------------------------------------------\n");
ret += trace_seq_printf(s, " | %d) %s-%d => %s-%d\n",
cpu, prev_comm, prev_pid, comm, pid);
ret += trace_seq_printf(s,
" ------------------------------------------\n\n");
"\n ------------------------------------------\n |");
if (!ret)
TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_cpu(s, cpu);
if (ret == TRACE_TYPE_PARTIAL_LINE)
TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_proc(s, prev_pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s, " => ");
if (!ret)
TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_proc(s, pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s,
"\n ------------------------------------------\n\n");
if (!ret)
TRACE_TYPE_PARTIAL_LINE;
return ret;
}
......@@ -288,12 +351,23 @@ print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
struct trace_entry *ent = iter->ent;
/* Pid */
if (!verif_pid(s, ent->pid, cpu))
if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
/* Cpu */
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
ret = print_graph_cpu(s, cpu);
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
}
/* Proc */
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
ret = print_graph_proc(s, ent->pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s, " | ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
......@@ -318,12 +392,23 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
duration = 9999999ULL;
/* Pid */
if (!verif_pid(s, ent->pid, cpu))
if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
/* Cpu */
if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
ret = print_graph_cpu(s, cpu);
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
}
/* Proc */
if (tracer_flags.val & TRACE_GRAPH_PRINT_PROC) {
ret = print_graph_proc(s, ent->pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s, " | ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
......
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