/*
*
* Function graph tracer.
- * Copyright (c) 2008 Frederic Weisbecker <fweisbec@gmail.com>
+ * Copyright (c) 2008-2009 Frederic Weisbecker <fweisbec@gmail.com>
* Mostly borrowed from function tracer which
* is Copyright (c) Steven Rostedt <srostedt@redhat.com>
*
#include <linux/debugfs.h>
#include <linux/uaccess.h>
#include <linux/ftrace.h>
+#include <linux/slab.h>
#include <linux/fs.h>
#include "trace.h"
+#include "trace_output.h"
+
+struct fgraph_cpu_data {
+ pid_t last_pid;
+ int depth;
+ int ignore;
+ unsigned long enter_funcs[FTRACE_RETFUNC_DEPTH];
+};
+
+struct fgraph_data {
+ struct fgraph_cpu_data *cpu_data;
+
+ /* Place to preserve last processed entry. */
+ struct ftrace_graph_ent_entry ent;
+ struct ftrace_graph_ret_entry ret;
+ int failed;
+ int cpu;
+};
#define TRACE_GRAPH_INDENT 2
#define TRACE_GRAPH_PRINT_CPU 0x2
#define TRACE_GRAPH_PRINT_OVERHEAD 0x4
#define TRACE_GRAPH_PRINT_PROC 0x8
+#define TRACE_GRAPH_PRINT_DURATION 0x10
+#define TRACE_GRAPH_PRINT_ABS_TIME 0x20
static struct tracer_opt trace_opts[] = {
- /* Display overruns ? */
+ /* Display overruns? (for self-debug purpose) */
{ TRACER_OPT(funcgraph-overrun, TRACE_GRAPH_PRINT_OVERRUN) },
/* Display CPU ? */
{ TRACER_OPT(funcgraph-cpu, TRACE_GRAPH_PRINT_CPU) },
{ TRACER_OPT(funcgraph-overhead, TRACE_GRAPH_PRINT_OVERHEAD) },
/* Display proc name/pid */
{ TRACER_OPT(funcgraph-proc, TRACE_GRAPH_PRINT_PROC) },
+ /* Display duration of execution */
+ { TRACER_OPT(funcgraph-duration, TRACE_GRAPH_PRINT_DURATION) },
+ /* Display absolute time of an entry */
+ { TRACER_OPT(funcgraph-abstime, TRACE_GRAPH_PRINT_ABS_TIME) },
{ } /* Empty entry */
};
static struct tracer_flags tracer_flags = {
/* Don't display overruns and proc by default */
- .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD,
+ .val = TRACE_GRAPH_PRINT_CPU | TRACE_GRAPH_PRINT_OVERHEAD |
+ TRACE_GRAPH_PRINT_DURATION,
.opts = trace_opts
};
-/* pid on the last trace processed */
-static pid_t last_pid[NR_CPUS] = { [0 ... NR_CPUS-1] = -1 };
+static struct trace_array *graph_array;
-static int graph_trace_init(struct trace_array *tr)
+
+/* Add a function return address to the trace stack on thread info.*/
+int
+ftrace_push_return_trace(unsigned long ret, unsigned long func, int *depth,
+ unsigned long frame_pointer)
+{
+ unsigned long long calltime;
+ int index;
+
+ if (!current->ret_stack)
+ return -EBUSY;
+
+ /*
+ * We must make sure the ret_stack is tested before we read
+ * anything else.
+ */
+ smp_rmb();
+
+ /* The return trace stack is full */
+ if (current->curr_ret_stack == FTRACE_RETFUNC_DEPTH - 1) {
+ atomic_inc(¤t->trace_overrun);
+ return -EBUSY;
+ }
+
+ calltime = trace_clock_local();
+
+ index = ++current->curr_ret_stack;
+ barrier();
+ current->ret_stack[index].ret = ret;
+ current->ret_stack[index].func = func;
+ current->ret_stack[index].calltime = calltime;
+ current->ret_stack[index].subtime = 0;
+ current->ret_stack[index].fp = frame_pointer;
+ *depth = index;
+
+ return 0;
+}
+
+/* Retrieve a function return address to the trace stack on thread info.*/
+static void
+ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
+ unsigned long frame_pointer)
+{
+ int index;
+
+ index = current->curr_ret_stack;
+
+ if (unlikely(index < 0)) {
+ ftrace_graph_stop();
+ WARN_ON(1);
+ /* Might as well panic, otherwise we have no where to go */
+ *ret = (unsigned long)panic;
+ return;
+ }
+
+#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+ /*
+ * The arch may choose to record the frame pointer used
+ * and check it here to make sure that it is what we expect it
+ * to be. If gcc does not set the place holder of the return
+ * address in the frame pointer, and does a copy instead, then
+ * the function graph trace will fail. This test detects this
+ * case.
+ *
+ * Currently, x86_32 with optimize for size (-Os) makes the latest
+ * gcc do the above.
+ */
+ if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
+ ftrace_graph_stop();
+ WARN(1, "Bad frame pointer: expected %lx, received %lx\n"
+ " from func %ps return to %lx\n",
+ current->ret_stack[index].fp,
+ frame_pointer,
+ (void *)current->ret_stack[index].func,
+ current->ret_stack[index].ret);
+ *ret = (unsigned long)panic;
+ return;
+ }
+#endif
+
+ *ret = current->ret_stack[index].ret;
+ trace->func = current->ret_stack[index].func;
+ trace->calltime = current->ret_stack[index].calltime;
+ trace->overrun = atomic_read(¤t->trace_overrun);
+ trace->depth = index;
+}
+
+/*
+ * Send the trace to the ring-buffer.
+ * @return the original return address.
+ */
+unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
+{
+ struct ftrace_graph_ret trace;
+ unsigned long ret;
+
+ ftrace_pop_return_trace(&trace, &ret, frame_pointer);
+ trace.rettime = trace_clock_local();
+ ftrace_graph_return(&trace);
+ barrier();
+ current->curr_ret_stack--;
+
+ if (unlikely(!ret)) {
+ ftrace_graph_stop();
+ WARN_ON(1);
+ /* Might as well panic. What else to do? */
+ ret = (unsigned long)panic;
+ }
+
+ return ret;
+}
+
+int __trace_graph_entry(struct trace_array *tr,
+ struct ftrace_graph_ent *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ftrace_event_call *call = &event_funcgraph_entry;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ftrace_graph_ent_entry *entry;
+
+ if (unlikely(__this_cpu_read(ftrace_cpu_disabled)))
+ return 0;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_ENT,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return 0;
+ entry = ring_buffer_event_data(event);
+ entry->graph_ent = *trace;
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ ring_buffer_unlock_commit(buffer, event);
+
+ return 1;
+}
+
+int trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+ struct trace_array *tr = graph_array;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int ret;
+ int cpu;
+ int pc;
+
+ if (!ftrace_trace_task(current))
+ return 0;
+
+ /* trace it when it is-nested-in or is a function enabled. */
+ if (!(trace->depth || ftrace_graph_addr(trace->func)))
+ return 0;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ ret = __trace_graph_entry(tr, trace, flags, pc);
+ } else {
+ ret = 0;
+ }
+
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+
+ return ret;
+}
+
+int trace_graph_thresh_entry(struct ftrace_graph_ent *trace)
+{
+ if (tracing_thresh)
+ return 1;
+ else
+ return trace_graph_entry(trace);
+}
+
+void __trace_graph_return(struct trace_array *tr,
+ struct ftrace_graph_ret *trace,
+ unsigned long flags,
+ int pc)
+{
+ struct ftrace_event_call *call = &event_funcgraph_exit;
+ struct ring_buffer_event *event;
+ struct ring_buffer *buffer = tr->buffer;
+ struct ftrace_graph_ret_entry *entry;
+
+ if (unlikely(__this_cpu_read(ftrace_cpu_disabled)))
+ return;
+
+ event = trace_buffer_lock_reserve(buffer, TRACE_GRAPH_RET,
+ sizeof(*entry), flags, pc);
+ if (!event)
+ return;
+ entry = ring_buffer_event_data(event);
+ entry->ret = *trace;
+ if (!filter_current_check_discard(buffer, call, entry, event))
+ ring_buffer_unlock_commit(buffer, event);
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
+{
+ struct trace_array *tr = graph_array;
+ struct trace_array_cpu *data;
+ unsigned long flags;
+ long disabled;
+ int cpu;
+ int pc;
+
+ local_irq_save(flags);
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+ disabled = atomic_inc_return(&data->disabled);
+ if (likely(disabled == 1)) {
+ pc = preempt_count();
+ __trace_graph_return(tr, trace, flags, pc);
+ }
+ atomic_dec(&data->disabled);
+ local_irq_restore(flags);
+}
+
+void set_graph_array(struct trace_array *tr)
+{
+ graph_array = tr;
+
+ /* Make graph_array visible before we start tracing */
+
+ smp_mb();
+}
+
+void trace_graph_thresh_return(struct ftrace_graph_ret *trace)
{
- int cpu, ret;
+ if (tracing_thresh &&
+ (trace->rettime - trace->calltime < tracing_thresh))
+ return;
+ else
+ trace_graph_return(trace);
+}
- for_each_online_cpu(cpu)
- tracing_reset(tr, cpu);
+static int graph_trace_init(struct trace_array *tr)
+{
+ int ret;
- ret = register_ftrace_graph(&trace_graph_return,
- &trace_graph_entry);
+ set_graph_array(tr);
+ if (tracing_thresh)
+ ret = register_ftrace_graph(&trace_graph_thresh_return,
+ &trace_graph_thresh_entry);
+ else
+ ret = register_ftrace_graph(&trace_graph_return,
+ &trace_graph_entry);
if (ret)
return ret;
tracing_start_cmdline_record();
unregister_ftrace_graph();
}
-static inline int log10_cpu(int nb)
-{
- if (nb / 100)
- return 3;
- if (nb / 10)
- return 2;
- return 1;
-}
+static int max_bytes_for_cpu;
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);
+ ret = trace_seq_printf(s, " %*d) ", max_bytes_for_cpu, cpu);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
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;
+ char comm[TASK_COMM_LEN];
/* sign + log10(MAX_INT) + '\0' */
char pid_str[11];
+ int spaces = 0;
+ int ret;
+ int len;
+ int i;
- strncpy(comm, trace_find_cmdline(pid), 7);
+ trace_find_cmdline(pid, comm);
comm[7] = '\0';
sprintf(pid_str, "%d", pid);
}
+static enum print_line_t
+print_graph_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
+{
+ if (!trace_seq_putc(s, ' '))
+ return 0;
+
+ return trace_print_lat_fmt(s, entry);
+}
+
/* If the pid changed since the last trace, output this event */
static enum print_line_t
-verif_pid(struct trace_seq *s, pid_t pid, int cpu)
+verif_pid(struct trace_seq *s, pid_t pid, int cpu, struct fgraph_data *data)
{
pid_t prev_pid;
+ pid_t *last_pid;
int ret;
- if (last_pid[cpu] != -1 && last_pid[cpu] == pid)
+ if (!data)
return TRACE_TYPE_HANDLED;
- prev_pid = last_pid[cpu];
- last_pid[cpu] = pid;
+ last_pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
+ if (*last_pid == pid)
+ return TRACE_TYPE_HANDLED;
+
+ prev_pid = *last_pid;
+ *last_pid = pid;
+
+ if (prev_pid == -1)
+ return TRACE_TYPE_HANDLED;
/*
* Context-switch trace line:
ret = trace_seq_printf(s,
" ------------------------------------------\n");
if (!ret)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_cpu(s, cpu);
if (ret == TRACE_TYPE_PARTIAL_LINE)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_proc(s, prev_pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s, " => ");
if (!ret)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
ret = print_graph_proc(s, pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
ret = trace_seq_printf(s,
"\n ------------------------------------------\n\n");
if (!ret)
- TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_PARTIAL_LINE;
- return ret;
+ return TRACE_TYPE_HANDLED;
}
-static bool
-trace_branch_is_leaf(struct trace_iterator *iter,
+static struct ftrace_graph_ret_entry *
+get_return_for_leaf(struct trace_iterator *iter,
struct ftrace_graph_ent_entry *curr)
{
- struct ring_buffer_iter *ring_iter;
+ struct fgraph_data *data = iter->private;
+ struct ring_buffer_iter *ring_iter = NULL;
struct ring_buffer_event *event;
struct ftrace_graph_ret_entry *next;
- ring_iter = iter->buffer_iter[iter->cpu];
-
- if (!ring_iter)
- return false;
+ /*
+ * If the previous output failed to write to the seq buffer,
+ * then we just reuse the data from before.
+ */
+ if (data && data->failed) {
+ curr = &data->ent;
+ next = &data->ret;
+ } else {
+
+ ring_iter = iter->buffer_iter[iter->cpu];
+
+ /* First peek to compare current entry and the next one */
+ if (ring_iter)
+ event = ring_buffer_iter_peek(ring_iter, NULL);
+ else {
+ /*
+ * We need to consume the current entry to see
+ * the next one.
+ */
+ ring_buffer_consume(iter->tr->buffer, iter->cpu,
+ NULL, NULL);
+ event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
+ NULL, NULL);
+ }
- event = ring_buffer_iter_peek(ring_iter, NULL);
+ if (!event)
+ return NULL;
- if (!event)
- return false;
+ next = ring_buffer_event_data(event);
- next = ring_buffer_event_data(event);
+ if (data) {
+ /*
+ * Save current and next entries for later reference
+ * if the output fails.
+ */
+ data->ent = *curr;
+ data->ret = *next;
+ }
+ }
if (next->ent.type != TRACE_GRAPH_RET)
- return false;
+ return NULL;
if (curr->ent.pid != next->ent.pid ||
curr->graph_ent.func != next->ret.func)
- return false;
+ return NULL;
+
+ /* this is a leaf, now advance the iterator */
+ if (ring_iter)
+ ring_buffer_read(ring_iter, NULL);
- return true;
+ return next;
}
+/* Signal a overhead of time execution to the output */
+static int
+print_graph_overhead(unsigned long long duration, struct trace_seq *s,
+ u32 flags)
+{
+ /* If duration disappear, we don't need anything */
+ if (!(flags & TRACE_GRAPH_PRINT_DURATION))
+ return 1;
+
+ /* Non nested entry or return */
+ if (duration == -1)
+ return trace_seq_printf(s, " ");
+
+ if (flags & TRACE_GRAPH_PRINT_OVERHEAD) {
+ /* 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, " ");
+}
+
+static int print_graph_abs_time(u64 t, struct trace_seq *s)
+{
+ unsigned long usecs_rem;
+
+ usecs_rem = do_div(t, NSEC_PER_SEC);
+ usecs_rem /= 1000;
+
+ return trace_seq_printf(s, "%5lu.%06lu | ",
+ (unsigned long)t, usecs_rem);
+}
static enum print_line_t
-print_graph_duration(unsigned long long duration, struct trace_seq *s)
+print_graph_irq(struct trace_iterator *iter, unsigned long addr,
+ enum trace_type type, int cpu, pid_t pid, u32 flags)
+{
+ int ret;
+ struct trace_seq *s = &iter->seq;
+
+ if (addr < (unsigned long)__irqentry_text_start ||
+ addr >= (unsigned long)__irqentry_text_end)
+ return TRACE_TYPE_UNHANDLED;
+
+ /* Absolute time */
+ if (flags & TRACE_GRAPH_PRINT_ABS_TIME) {
+ ret = print_graph_abs_time(iter->ts, s);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Cpu */
+ if (flags & TRACE_GRAPH_PRINT_CPU) {
+ ret = print_graph_cpu(s, cpu);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Proc */
+ if (flags & TRACE_GRAPH_PRINT_PROC) {
+ ret = print_graph_proc(s, pid);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ ret = trace_seq_printf(s, " | ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* No overhead */
+ ret = print_graph_overhead(-1, s, flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ if (type == TRACE_GRAPH_ENT)
+ ret = trace_seq_printf(s, "==========>");
+ else
+ ret = trace_seq_printf(s, "<==========");
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* Don't close the duration column if haven't one */
+ if (flags & TRACE_GRAPH_PRINT_DURATION)
+ trace_seq_printf(s, " |");
+ ret = trace_seq_printf(s, "\n");
+
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ return TRACE_TYPE_HANDLED;
+}
+
+enum print_line_t
+trace_print_graph_duration(unsigned long long duration, struct trace_seq *s)
{
unsigned long nsecs_rem = do_div(duration, 1000);
/* log10(ULONG_MAX) + '\0' */
sprintf(msecs_str, "%lu", (unsigned long) duration);
/* Print msecs */
- ret = trace_seq_printf(s, msecs_str);
+ ret = trace_seq_printf(s, "%s", msecs_str);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
-
- ret = trace_seq_printf(s, "| ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
return TRACE_TYPE_HANDLED;
-
}
-/* Signal a overhead of time execution to the output */
-static int
-print_graph_overhead(unsigned long long duration, struct trace_seq *s)
+static enum print_line_t
+print_graph_duration(unsigned long long duration, struct trace_seq *s)
{
- /* Duration exceeded 100 msecs */
- if (duration > 100000ULL)
- return trace_seq_printf(s, "! ");
+ int ret;
- /* Duration exceeded 10 msecs */
- if (duration > 10000ULL)
- return trace_seq_printf(s, "+ ");
+ ret = trace_print_graph_duration(duration, s);
+ if (ret != TRACE_TYPE_HANDLED)
+ return ret;
- return trace_seq_printf(s, " ");
+ ret = trace_seq_printf(s, "| ");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ return TRACE_TYPE_HANDLED;
}
/* Case of a leaf function on its call entry */
static enum print_line_t
print_graph_entry_leaf(struct trace_iterator *iter,
- struct ftrace_graph_ent_entry *entry, struct trace_seq *s)
+ struct ftrace_graph_ent_entry *entry,
+ struct ftrace_graph_ret_entry *ret_entry,
+ struct trace_seq *s, u32 flags)
{
- struct ftrace_graph_ret_entry *ret_entry;
+ struct fgraph_data *data = iter->private;
struct ftrace_graph_ret *graph_ret;
- struct ring_buffer_event *event;
struct ftrace_graph_ent *call;
unsigned long long duration;
int ret;
int i;
- 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;
- /* Overhead */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
- ret = print_graph_overhead(duration, s);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
+ if (data) {
+ struct fgraph_cpu_data *cpu_data;
+ int cpu = iter->cpu;
+
+ cpu_data = per_cpu_ptr(data->cpu_data, cpu);
+
+ /*
+ * Comments display at + 1 to depth. Since
+ * this is a leaf function, keep the comments
+ * equal to this depth.
+ */
+ cpu_data->depth = call->depth - 1;
+
+ /* No need to keep this function around for this depth */
+ if (call->depth < FTRACE_RETFUNC_DEPTH)
+ cpu_data->enter_funcs[call->depth] = 0;
}
- /* Duration */
- ret = print_graph_duration(duration, s);
- if (ret == TRACE_TYPE_PARTIAL_LINE)
+ /* Overhead */
+ ret = print_graph_overhead(duration, s, flags);
+ if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
+ /* Duration */
+ if (flags & TRACE_GRAPH_PRINT_DURATION) {
+ ret = print_graph_duration(duration, s);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
/* Function */
for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++) {
ret = trace_seq_printf(s, " ");
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");
+ ret = trace_seq_printf(s, "%ps();\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
static enum print_line_t
-print_graph_entry_nested(struct ftrace_graph_ent_entry *entry,
- struct trace_seq *s)
+print_graph_entry_nested(struct trace_iterator *iter,
+ struct ftrace_graph_ent_entry *entry,
+ struct trace_seq *s, int cpu, u32 flags)
{
- int i;
- int ret;
struct ftrace_graph_ent *call = &entry->graph_ent;
+ struct fgraph_data *data = iter->private;
+ int ret;
+ int i;
+
+ if (data) {
+ struct fgraph_cpu_data *cpu_data;
+ int cpu = iter->cpu;
+
+ cpu_data = per_cpu_ptr(data->cpu_data, cpu);
+ cpu_data->depth = call->depth;
+
+ /* Save this function pointer to see if the exit matches */
+ if (call->depth < FTRACE_RETFUNC_DEPTH)
+ cpu_data->enter_funcs[call->depth] = call->func;
+ }
/* No overhead */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
- ret = trace_seq_printf(s, " ");
+ ret = print_graph_overhead(-1, s, flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* No time */
+ if (flags & TRACE_GRAPH_PRINT_DURATION) {
+ 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, " ");
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = seq_print_ip_sym(s, call->func, 0);
+ ret = trace_seq_printf(s, "%ps() {\n", (void *)call->func);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- ret = trace_seq_printf(s, "() {\n");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- return TRACE_TYPE_HANDLED;
+ /*
+ * we already consumed the current entry to check the next one
+ * and see if this is a leaf.
+ */
+ return TRACE_TYPE_NO_CONSUME;
}
static enum print_line_t
-print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
- struct trace_iterator *iter, int cpu)
+print_graph_prologue(struct trace_iterator *iter, struct trace_seq *s,
+ int type, unsigned long addr, u32 flags)
{
- int ret;
+ struct fgraph_data *data = iter->private;
struct trace_entry *ent = iter->ent;
+ int cpu = iter->cpu;
+ int ret;
/* Pid */
- if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
+ if (verif_pid(s, ent->pid, cpu, data) == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
+ if (type) {
+ /* Interrupt */
+ ret = print_graph_irq(iter, addr, type, cpu, ent->pid, flags);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ /* Absolute time */
+ if (flags & TRACE_GRAPH_PRINT_ABS_TIME) {
+ ret = print_graph_abs_time(iter->ts, s);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
/* Cpu */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
+ if (flags & 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) {
+ if (flags & TRACE_GRAPH_PRINT_PROC) {
ret = print_graph_proc(s, ent->pid);
if (ret == TRACE_TYPE_PARTIAL_LINE)
return TRACE_TYPE_PARTIAL_LINE;
return TRACE_TYPE_PARTIAL_LINE;
}
- if (trace_branch_is_leaf(iter, field))
- return print_graph_entry_leaf(iter, field, s);
+ /* Latency format */
+ if (trace_flags & TRACE_ITER_LATENCY_FMT) {
+ ret = print_graph_lat_fmt(s, ent);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
+
+ return 0;
+}
+
+static enum print_line_t
+print_graph_entry(struct ftrace_graph_ent_entry *field, struct trace_seq *s,
+ struct trace_iterator *iter, u32 flags)
+{
+ struct fgraph_data *data = iter->private;
+ struct ftrace_graph_ent *call = &field->graph_ent;
+ struct ftrace_graph_ret_entry *leaf_ret;
+ static enum print_line_t ret;
+ int cpu = iter->cpu;
+
+ if (print_graph_prologue(iter, s, TRACE_GRAPH_ENT, call->func, flags))
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ leaf_ret = get_return_for_leaf(iter, field);
+ if (leaf_ret)
+ ret = print_graph_entry_leaf(iter, field, leaf_ret, s, flags);
else
- return print_graph_entry_nested(field, s);
+ ret = print_graph_entry_nested(iter, field, s, cpu, flags);
+
+ if (data) {
+ /*
+ * If we failed to write our output, then we need to make
+ * note of it. Because we already consumed our entry.
+ */
+ if (s->full) {
+ data->failed = 1;
+ data->cpu = cpu;
+ } else
+ data->failed = 0;
+ }
+ return ret;
}
static enum print_line_t
print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
- struct trace_entry *ent, int cpu)
+ struct trace_entry *ent, struct trace_iterator *iter,
+ u32 flags)
{
- int i;
- int ret;
unsigned long long duration = trace->rettime - trace->calltime;
+ struct fgraph_data *data = iter->private;
+ pid_t pid = ent->pid;
+ int cpu = iter->cpu;
+ int func_match = 1;
+ int ret;
+ int i;
- /* Pid */
- if (verif_pid(s, ent->pid, cpu) == TRACE_TYPE_PARTIAL_LINE)
- return TRACE_TYPE_PARTIAL_LINE;
+ if (data) {
+ struct fgraph_cpu_data *cpu_data;
+ int cpu = iter->cpu;
- /* 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;
- }
+ cpu_data = per_cpu_ptr(data->cpu_data, cpu);
- /* 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;
+ /*
+ * Comments display at + 1 to depth. This is the
+ * return from a function, we now want the comments
+ * to display at the same level of the bracket.
+ */
+ cpu_data->depth = trace->depth - 1;
- ret = trace_seq_printf(s, " | ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
+ if (trace->depth < FTRACE_RETFUNC_DEPTH) {
+ if (cpu_data->enter_funcs[trace->depth] != trace->func)
+ func_match = 0;
+ cpu_data->enter_funcs[trace->depth] = 0;
+ }
}
+ if (print_graph_prologue(iter, s, 0, 0, flags))
+ 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;
- }
+ ret = print_graph_overhead(duration, s, flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
/* Duration */
- ret = print_graph_duration(duration, s);
- if (ret == TRACE_TYPE_PARTIAL_LINE)
- return TRACE_TYPE_PARTIAL_LINE;
+ if (flags & TRACE_GRAPH_PRINT_DURATION) {
+ ret = print_graph_duration(duration, s);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
/* Closing brace */
for (i = 0; i < trace->depth * TRACE_GRAPH_INDENT; i++) {
return TRACE_TYPE_PARTIAL_LINE;
}
- ret = trace_seq_printf(s, "}\n");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
+ /*
+ * If the return function does not have a matching entry,
+ * then the entry was lost. Instead of just printing
+ * the '}' and letting the user guess what function this
+ * belongs to, write out the function name.
+ */
+ if (func_match) {
+ ret = trace_seq_printf(s, "}\n");
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ } else {
+ ret = trace_seq_printf(s, "} /* %ps */\n", (void *)trace->func);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+ }
/* Overrun */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERRUN) {
+ if (flags & TRACE_GRAPH_PRINT_OVERRUN) {
ret = trace_seq_printf(s, " (Overruns: %lu)\n",
trace->overrun);
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
+
+ ret = print_graph_irq(iter, trace->func, TRACE_GRAPH_RET,
+ cpu, pid, flags);
+ if (ret == TRACE_TYPE_PARTIAL_LINE)
+ return TRACE_TYPE_PARTIAL_LINE;
+
return TRACE_TYPE_HANDLED;
}
static enum print_line_t
-print_graph_comment(struct print_entry *trace, struct trace_seq *s,
- struct trace_entry *ent, struct trace_iterator *iter)
+print_graph_comment(struct trace_seq *s, struct trace_entry *ent,
+ struct trace_iterator *iter, u32 flags)
{
- int i;
+ unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
+ struct fgraph_data *data = iter->private;
+ struct trace_event *event;
+ int depth = 0;
int ret;
+ int i;
- /* Pid */
- if (verif_pid(s, ent->pid, iter->cpu) == TRACE_TYPE_PARTIAL_LINE)
- return TRACE_TYPE_PARTIAL_LINE;
-
- /* Cpu */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_CPU) {
- ret = print_graph_cpu(s, iter->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;
+ if (data)
+ depth = per_cpu_ptr(data->cpu_data, iter->cpu)->depth;
- ret = trace_seq_printf(s, " | ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
- }
+ if (print_graph_prologue(iter, s, 0, 0, flags))
+ return TRACE_TYPE_PARTIAL_LINE;
/* No overhead */
- if (tracer_flags.val & TRACE_GRAPH_PRINT_OVERHEAD) {
- ret = trace_seq_printf(s, " ");
+ ret = print_graph_overhead(-1, s, flags);
+ if (!ret)
+ return TRACE_TYPE_PARTIAL_LINE;
+
+ /* No time */
+ if (flags & TRACE_GRAPH_PRINT_DURATION) {
+ ret = trace_seq_printf(s, " | ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
- /* No time */
- ret = trace_seq_printf(s, " | ");
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
/* Indentation */
- if (trace->depth > 0)
- for (i = 0; i < (trace->depth + 1) * TRACE_GRAPH_INDENT; i++) {
+ if (depth > 0)
+ for (i = 0; i < (depth + 1) * TRACE_GRAPH_INDENT; i++) {
ret = trace_seq_printf(s, " ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
}
/* The comment */
- ret = trace_seq_printf(s, "/* %s", trace->buf);
+ ret = trace_seq_printf(s, "/* ");
if (!ret)
return TRACE_TYPE_PARTIAL_LINE;
- if (ent->flags & TRACE_FLAG_CONT)
- trace_seq_print_cont(s, iter);
+ switch (iter->ent->type) {
+ case TRACE_BPRINT:
+ ret = trace_print_bprintk_msg_only(iter);
+ if (ret != TRACE_TYPE_HANDLED)
+ return ret;
+ break;
+ case TRACE_PRINT:
+ ret = trace_print_printk_msg_only(iter);
+ if (ret != TRACE_TYPE_HANDLED)
+ return ret;
+ break;
+ default:
+ event = ftrace_find_event(ent->type);
+ if (!event)
+ return TRACE_TYPE_UNHANDLED;
+
+ ret = event->funcs->trace(iter, sym_flags, event);
+ if (ret != TRACE_TYPE_HANDLED)
+ return ret;
+ }
+
+ /* Strip ending newline */
+ if (s->buffer[s->len - 1] == '\n') {
+ s->buffer[s->len - 1] = '\0';
+ s->len--;
+ }
ret = trace_seq_printf(s, " */\n");
if (!ret)
enum print_line_t
-print_graph_function(struct trace_iterator *iter)
+print_graph_function_flags(struct trace_iterator *iter, u32 flags)
{
- struct trace_seq *s = &iter->seq;
+ struct ftrace_graph_ent_entry *field;
+ struct fgraph_data *data = iter->private;
struct trace_entry *entry = iter->ent;
+ struct trace_seq *s = &iter->seq;
+ int cpu = iter->cpu;
+ int ret;
+
+ if (data && per_cpu_ptr(data->cpu_data, cpu)->ignore) {
+ per_cpu_ptr(data->cpu_data, cpu)->ignore = 0;
+ return TRACE_TYPE_HANDLED;
+ }
+
+ /*
+ * If the last output failed, there's a possibility we need
+ * to print out the missing entry which would never go out.
+ */
+ if (data && data->failed) {
+ field = &data->ent;
+ iter->cpu = data->cpu;
+ ret = print_graph_entry(field, s, iter, flags);
+ if (ret == TRACE_TYPE_HANDLED && iter->cpu != cpu) {
+ per_cpu_ptr(data->cpu_data, iter->cpu)->ignore = 1;
+ ret = TRACE_TYPE_NO_CONSUME;
+ }
+ iter->cpu = cpu;
+ return ret;
+ }
switch (entry->type) {
case TRACE_GRAPH_ENT: {
- struct ftrace_graph_ent_entry *field;
+ /*
+ * print_graph_entry() may consume the current event,
+ * thus @field may become invalid, so we need to save it.
+ * sizeof(struct ftrace_graph_ent_entry) is very small,
+ * it can be safely saved at the stack.
+ */
+ struct ftrace_graph_ent_entry saved;
trace_assign_type(field, entry);
- return print_graph_entry(field, s, iter,
- iter->cpu);
+ saved = *field;
+ return print_graph_entry(&saved, s, iter, flags);
}
case TRACE_GRAPH_RET: {
struct ftrace_graph_ret_entry *field;
trace_assign_type(field, entry);
- return print_graph_return(&field->ret, s, entry, iter->cpu);
- }
- case TRACE_PRINT: {
- struct print_entry *field;
- trace_assign_type(field, entry);
- return print_graph_comment(field, s, entry, iter);
+ return print_graph_return(&field->ret, s, entry, iter, flags);
}
- default:
+ case TRACE_STACK:
+ case TRACE_FN:
+ /* dont trace stack and functions as comments */
return TRACE_TYPE_UNHANDLED;
+
+ default:
+ return print_graph_comment(s, entry, iter, flags);
}
+
+ return TRACE_TYPE_HANDLED;
+}
+
+static enum print_line_t
+print_graph_function(struct trace_iterator *iter)
+{
+ return print_graph_function_flags(iter, tracer_flags.val);
}
+static enum print_line_t
+print_graph_function_event(struct trace_iterator *iter, int flags,
+ struct trace_event *event)
+{
+ return print_graph_function(iter);
+}
+
+static void print_lat_header(struct seq_file *s, u32 flags)
+{
+ static const char spaces[] = " " /* 16 spaces */
+ " " /* 4 spaces */
+ " "; /* 17 spaces */
+ int size = 0;
+
+ if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
+ size += 16;
+ if (flags & TRACE_GRAPH_PRINT_CPU)
+ size += 4;
+ if (flags & TRACE_GRAPH_PRINT_PROC)
+ size += 17;
+
+ seq_printf(s, "#%.*s _-----=> irqs-off \n", size, spaces);
+ seq_printf(s, "#%.*s / _----=> need-resched \n", size, spaces);
+ seq_printf(s, "#%.*s| / _---=> hardirq/softirq \n", size, spaces);
+ seq_printf(s, "#%.*s|| / _--=> preempt-depth \n", size, spaces);
+ seq_printf(s, "#%.*s||| / _-=> lock-depth \n", size, spaces);
+ seq_printf(s, "#%.*s|||| / \n", size, spaces);
+}
+
+void print_graph_headers_flags(struct seq_file *s, u32 flags)
+{
+ int lat = trace_flags & TRACE_ITER_LATENCY_FMT;
+
+ if (lat)
+ print_lat_header(s, flags);
+
+ /* 1st line */
+ seq_printf(s, "#");
+ if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
+ seq_printf(s, " TIME ");
+ if (flags & TRACE_GRAPH_PRINT_CPU)
+ seq_printf(s, " CPU");
+ if (flags & TRACE_GRAPH_PRINT_PROC)
+ seq_printf(s, " TASK/PID ");
+ if (lat)
+ seq_printf(s, "|||||");
+ if (flags & TRACE_GRAPH_PRINT_DURATION)
+ seq_printf(s, " DURATION ");
+ seq_printf(s, " FUNCTION CALLS\n");
+
+ /* 2nd line */
+ seq_printf(s, "#");
+ if (flags & TRACE_GRAPH_PRINT_ABS_TIME)
+ seq_printf(s, " | ");
+ if (flags & TRACE_GRAPH_PRINT_CPU)
+ seq_printf(s, " | ");
+ if (flags & TRACE_GRAPH_PRINT_PROC)
+ seq_printf(s, " | | ");
+ if (lat)
+ seq_printf(s, "|||||");
+ if (flags & TRACE_GRAPH_PRINT_DURATION)
+ seq_printf(s, " | | ");
+ seq_printf(s, " | | | |\n");
+}
+
+void print_graph_headers(struct seq_file *s)
+{
+ print_graph_headers_flags(s, tracer_flags.val);
+}
+
+void graph_trace_open(struct trace_iterator *iter)
+{
+ /* pid and depth on the last trace processed */
+ struct fgraph_data *data;
+ int cpu;
+
+ iter->private = NULL;
+
+ data = kzalloc(sizeof(*data), GFP_KERNEL);
+ if (!data)
+ goto out_err;
+
+ data->cpu_data = alloc_percpu(struct fgraph_cpu_data);
+ if (!data->cpu_data)
+ goto out_err_free;
+
+ for_each_possible_cpu(cpu) {
+ pid_t *pid = &(per_cpu_ptr(data->cpu_data, cpu)->last_pid);
+ int *depth = &(per_cpu_ptr(data->cpu_data, cpu)->depth);
+ int *ignore = &(per_cpu_ptr(data->cpu_data, cpu)->ignore);
+ *pid = -1;
+ *depth = 0;
+ *ignore = 0;
+ }
+
+ iter->private = data;
+
+ return;
+
+ out_err_free:
+ kfree(data);
+ out_err:
+ pr_warning("function graph tracer: not enough memory\n");
+}
+
+void graph_trace_close(struct trace_iterator *iter)
+{
+ struct fgraph_data *data = iter->private;
+
+ if (data) {
+ free_percpu(data->cpu_data);
+ kfree(data);
+ }
+}
+
+static struct trace_event_functions graph_functions = {
+ .trace = print_graph_function_event,
+};
+
+static struct trace_event graph_trace_entry_event = {
+ .type = TRACE_GRAPH_ENT,
+ .funcs = &graph_functions,
+};
+
+static struct trace_event graph_trace_ret_event = {
+ .type = TRACE_GRAPH_RET,
+ .funcs = &graph_functions
+};
+
static struct tracer graph_trace __read_mostly = {
- .name = "function_graph",
- .init = graph_trace_init,
- .reset = graph_trace_reset,
- .print_line = print_graph_function,
+ .name = "function_graph",
+ .open = graph_trace_open,
+ .pipe_open = graph_trace_open,
+ .close = graph_trace_close,
+ .pipe_close = graph_trace_close,
+ .wait_pipe = poll_wait_pipe,
+ .init = graph_trace_init,
+ .reset = graph_trace_reset,
+ .print_line = print_graph_function,
+ .print_header = print_graph_headers,
.flags = &tracer_flags,
+#ifdef CONFIG_FTRACE_SELFTEST
+ .selftest = trace_selftest_startup_function_graph,
+#endif
};
static __init int init_graph_trace(void)
{
+ max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
+
+ if (!register_ftrace_event(&graph_trace_entry_event)) {
+ pr_warning("Warning: could not register graph trace events\n");
+ return 1;
+ }
+
+ if (!register_ftrace_event(&graph_trace_ret_event)) {
+ pr_warning("Warning: could not register graph trace events\n");
+ return 1;
+ }
+
return register_tracer(&graph_trace);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff