aboutsummaryrefslogtreecommitdiff
path: root/kernel/trace
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/ftrace.c27
-rw-r--r--kernel/trace/trace.c2
-rw-r--r--kernel/trace/trace_branch.c1
-rw-r--r--kernel/trace/trace_functions_graph.c267
4 files changed, 259 insertions, 38 deletions
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cbf8b09f63a..08b536a2614 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -786,7 +786,6 @@ enum {
#define FTRACE_BUFF_MAX (KSYM_SYMBOL_LEN+4) /* room for wildcards */
struct ftrace_iterator {
- loff_t pos;
struct ftrace_page *pg;
unsigned idx;
unsigned flags;
@@ -811,6 +810,8 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
iter->pg = iter->pg->next;
iter->idx = 0;
goto retry;
+ } else {
+ iter->idx = -1;
}
} else {
rec = &iter->pg->records[iter->idx++];
@@ -833,8 +834,6 @@ t_next(struct seq_file *m, void *v, loff_t *pos)
}
spin_unlock(&ftrace_lock);
- iter->pos = *pos;
-
return rec;
}
@@ -842,13 +841,15 @@ static void *t_start(struct seq_file *m, loff_t *pos)
{
struct ftrace_iterator *iter = m->private;
void *p = NULL;
- loff_t l = -1;
- if (*pos > iter->pos)
- *pos = iter->pos;
+ if (*pos > 0) {
+ if (iter->idx < 0)
+ return p;
+ (*pos)--;
+ iter->idx--;
+ }
- l = *pos;
- p = t_next(m, p, &l);
+ p = t_next(m, p, pos);
return p;
}
@@ -859,21 +860,15 @@ static void t_stop(struct seq_file *m, void *p)
static int t_show(struct seq_file *m, void *v)
{
- struct ftrace_iterator *iter = m->private;
struct dyn_ftrace *rec = v;
char str[KSYM_SYMBOL_LEN];
- int ret = 0;
if (!rec)
return 0;
kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
- ret = seq_printf(m, "%s\n", str);
- if (ret < 0) {
- iter->pos--;
- iter->idx--;
- }
+ seq_printf(m, "%s\n", str);
return 0;
}
@@ -899,7 +894,6 @@ ftrace_avail_open(struct inode *inode, struct file *file)
return -ENOMEM;
iter->pg = ftrace_pages_start;
- iter->pos = 0;
ret = seq_open(file, &show_ftrace_seq_ops);
if (!ret) {
@@ -986,7 +980,6 @@ ftrace_regex_open(struct inode *inode, struct file *file, int enable)
if (file->f_mode & FMODE_READ) {
iter->pg = ftrace_pages_start;
- iter->pos = 0;
iter->flags = enable ? FTRACE_ITER_FILTER :
FTRACE_ITER_NOTRACE;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5811e0a5f73..91887a280ab 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -983,6 +983,7 @@ static void ftrace_trace_userstack(struct trace_array *tr,
struct trace_array_cpu *data,
unsigned long flags, int pc)
{
+#ifdef CONFIG_STACKTRACE
struct ring_buffer_event *event;
struct userstack_entry *entry;
struct stack_trace trace;
@@ -1008,6 +1009,7 @@ static void ftrace_trace_userstack(struct trace_array *tr,
save_stack_trace_user(&trace);
ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
+#endif
}
void __trace_userstack(struct trace_array *tr,
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 877ee88e6a7..bc972753568 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -6,6 +6,7 @@
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
+#include <linux/irqflags.h>
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/module.h>
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index d31d695174a..894b50bca31 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -15,15 +15,24 @@
#define TRACE_GRAPH_INDENT 2
+/* Flag options */
#define TRACE_GRAPH_PRINT_OVERRUN 0x1
+#define TRACE_GRAPH_PRINT_CPU 0x2
+#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
+
static struct tracer_opt trace_opts[] = {
- /* Display overruns or not */
- { TRACER_OPT(overrun, TRACE_GRAPH_PRINT_OVERRUN) },
+ /* Display overruns ? */
+ { TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) },
+ /* Display CPU ? */
+ { TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) },
+ /* Display Overhead ? */
+ { TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) },
{ } /* Empty entry */
};
static struct tracer_flags tracer_flags = {
- .val = 0, /* Don't display overruns by default */
+ /* Don't display overruns by default */
+ .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD,
.opts = trace_opts
};
@@ -52,37 +61,208 @@ static void graph_trace_reset(struct trace_array *tr)
unregister_ftrace_graph();
}
+static inline int log10_cpu(int nb)
+{
+ if (nb / 100)
+ return 3;
+ if (nb / 10)
+ return 2;
+ return 1;
+}
+
+static enum print_line_t
+print_graph_cpu(struct trace_seq *s, int cpu)
+{
+ int i;
+ int ret;
+ int log10_this = log10_cpu(cpu);
+ int log10_all = log10_cpu(cpus_weight_nr(cpu_online_map));
+
+
+ /*
+ * Start with a space character - to make it stand out
+ * to the right a bit when trace output is pasted into
+ * email:
+ */
+ ret = trace_seq_printf(s, " ");
+
+ /*
+ * Tricky - we space the CPU field according to the max
+ * number of online CPUs. On a 2-cpu system it would take
+ * a maximum of 1 digit - on a 128 cpu system it would
+ * take up to 3 digits:
+ */
+ for (i = 0; i < log10_all - log10_this; i++) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+ ret = trace_seq_printf(s, "%d) ", cpu);
+ 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)
{
- char *comm;
+ char *comm, *prev_comm;
+ pid_t prev_pid;
+ int ret;
if (last_pid[cpu] != -1 && last_pid[cpu] == pid)
return 1;
+ prev_pid = last_pid[cpu];
last_pid[cpu] = pid;
+
comm = trace_find_cmdline(pid);
+ prev_comm = trace_find_cmdline(prev_pid);
- return trace_seq_printf(s, "\nCPU[%03d]"
- " ------------8<---------- thread %s-%d"
- " ------------8<----------\n\n",
- cpu, comm, pid);
+/*
+ * Context-switch trace line:
+
+ ------------------------------------------
+ | 1) migration/0--1 => sshd-1755
+ ------------------------------------------
+
+ */
+ 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");
+ return ret;
}
+static bool
+trace_branch_is_leaf(struct trace_iterator *iter,
+ struct ftrace_graph_ent_entry *curr)
+{
+ struct ring_buffer_iter *ring_iter;
+ struct ring_buffer_event *event;
+ struct ftrace_graph_ret_entry *next;
+
+ ring_iter = iter->buffer_iter[iter->cpu];
+
+ if (!ring_iter)
+ return false;
+
+ event = ring_buffer_iter_peek(ring_iter, NULL);
+
+ if (!event)
+ return false;
+
+ next = ring_buffer_event_data(event);
+
+ if (next->ent.type != TRACE_GRAPH_RET)
+ return false;
+
+ if (curr->ent.pid != next->ent.pid ||
+ curr->graph_ent.func != next->ret.func)
+ return false;
+
+ return true;
+}
+
+
+static inline int
+print_graph_duration(unsigned long long duration, struct trace_seq *s)
+{
+ unsigned long nsecs_rem = do_div(duration, 1000);
+ return trace_seq_printf(s, "%4llu.%3lu us | ", duration, nsecs_rem);
+}
+
+/* Signal a overhead of time execution to the output */
+static int
+print_graph_overhead(unsigned long long duration, struct trace_seq *s)
+{
+ /* Duration exceeded 100 msecs */
+ if (duration > 100000ULL)
+ return trace_seq_printf(s, "! ");
+
+ /* Duration exceeded 10 msecs */
+ if (duration > 10000ULL)
+ return trace_seq_printf(s, "+ ");
+
+ return trace_seq_printf(s, " ");
+}
+
+/* Case of a leaf function on its call entry */
static enum print_line_t
-print_graph_entry(struct ftrace_graph_ent *call, struct trace_seq *s,
- struct trace_entry *ent, int cpu)
+print_graph_entry_leaf(struct trace_iterator *iter,
+ struct ftrace_graph_ent_entry *entry, struct trace_seq *s)
{
- int i;
+ struct ftrace_graph_ret_entry *ret_entry;
+ struct ftrace_graph_ret *graph_ret;
+ struct ring_buffer_event *event;
+ struct ftrace_graph_ent *call;
+ unsigned long long duration;
int ret;
+ int i;
- if (!verif_pid(s, ent->pid, cpu))
+ event = ring_buffer_read(iter->buffer_iter[iter->cpu], NULL);
+ ret_entry = ring_buffer_event_data(event);
+ graph_ret = &ret_entry->ret;
+ call = &entry->graph_ent;
+ duration = graph_ret->rettime - graph_ret->calltime;
+
+ /* Must not exceed 8 characters: 9999.999 us */
+ if (duration > 10000000ULL)
+ duration = 9999999ULL;
+
+ /* Overhead */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+ ret = print_graph_overhead(duration, s);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Duration */
+ ret = print_graph_duration(duration, s);
+ if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- ret = trace_seq_printf(s, "CPU[%03d] ", cpu);
+ /* Function */
+ for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ ret = seq_print_ip_sym(s, call->func, 0);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ ret = trace_seq_printf(s, "();\n");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_entry_nested(struct ftrace_graph_ent_entry *entry,
+ struct trace_seq *s)
+{
+ int i;
+ int ret;
+ struct ftrace_graph_ent *call = &entry->graph_ent;
+
+ /* No overhead */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+ ret = trace_seq_printf(s, " ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* No time */
+ ret = trace_seq_printf(s, " | ");
+
+ /* Function */
for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
ret = trace_seq_printf(s, " ");
if (!ret)
@@ -96,37 +276,82 @@ print_graph_entry(struct ftrace_graph_ent *call, struct trace_seq *s,
ret = trace_seq_printf(s, "() {\n");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
+
return TRACE_TYPE_HANDLED;
}
static enum print_line_t
+print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
+ struct trace_iterator *iter, int cpu)
+{
+ int ret;
+ struct trace_entry *ent = iter->ent;
+
+ /* Pid */
+ if (!verif_pid(s, ent->pid, cpu))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Cpu */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+ ret = print_graph_cpu(s, cpu);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ if (trace_branch_is_leaf(iter, field))
+ return print_graph_entry_leaf(iter, field, s);
+ else
+ return print_graph_entry_nested(field, s);
+
+}
+
+static enum print_line_t
print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
struct trace_entry *ent, int cpu)
{
int i;
int ret;
+ unsigned long long duration = trace->rettime - trace->calltime;
+
+ /* Must not exceed 8 characters: xxxx.yyy us */
+ if (duration > 10000000ULL)
+ duration = 9999999ULL;
+ /* Pid */
if (!verif_pid(s, ent->pid, cpu))
return TRACE_TYPE_PARTIAL_LINE;
- ret = trace_seq_printf(s, "CPU[%03d] ", cpu);
+ /* Cpu */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+ ret = print_graph_cpu(s, cpu);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Overhead */
+ if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
+ ret = print_graph_overhead(duration, s);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Duration */
+ ret = print_graph_duration(duration, s);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
+ /* Closing brace */
for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
ret = trace_seq_printf(s, " ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = trace_seq_printf(s, "} ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- ret = trace_seq_printf(s, "%llu\n", trace->rettime - trace->calltime);
+ ret = trace_seq_printf(s, "}\n");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
+ /* Overrun */
if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
ret = trace_seq_printf(s, " (Overruns: %lu)\n",
trace->overrun);
@@ -146,7 +371,7 @@ print_graph_function(struct trace_iterator *iter)
case TRACE_GRAPH_ENT: {
struct ftrace_graph_ent_entry *field;
trace_assign_type(field, entry);
- return print_graph_entry(&field->graph_ent, s, entry,
+ return print_graph_entry(field, s, iter,
iter->cpu);
}
case TRACE_GRAPH_RET: {
@@ -160,7 +385,7 @@ print_graph_function(struct trace_iterator *iter)
}
static struct tracer graph_trace __read_mostly = {
- .name = "function-graph",
+ .name = "function_graph",
.init = graph_trace_init,
.reset = graph_trace_reset,
.print_line = print_graph_function,