* Copyright (C) 2004-2006 Ingo Molnar
* Copyright (C) 2004 William Lee Irwin III
*/
+#include <linux/ring_buffer.h>
#include <linux/utsrelease.h>
+#include <linux/stacktrace.h>
+#include <linux/writeback.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
#include <linux/notifier.h>
+#include <linux/irqflags.h>
#include <linux/debugfs.h>
#include <linux/pagemap.h>
#include <linux/hardirq.h>
#include <linux/linkage.h>
#include <linux/uaccess.h>
+#include <linux/kprobes.h>
#include <linux/ftrace.h>
#include <linux/module.h>
#include <linux/percpu.h>
+#include <linux/splice.h>
#include <linux/kdebug.h>
+#include <linux/string.h>
#include <linux/ctype.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/gfp.h>
#include <linux/fs.h>
-#include <linux/kprobes.h>
-#include <linux/writeback.h>
-#include <linux/splice.h>
-
-#include <linux/stacktrace.h>
-#include <linux/ring_buffer.h>
-#include <linux/irqflags.h>
#include "trace.h"
#include "trace_output.h"
unsigned long __read_mostly tracing_thresh;
/*
+ * On boot up, the ring buffer is set to the minimum size, so that
+ * we do not waste memory on systems that are not using tracing.
+ */
+static int ring_buffer_expanded;
+
+/*
* We need to change this state when a selftest is running.
* A selftest will lurk into the ring-buffer to count the
* entries inserted during the selftest although some concurrent
- * insertions into the ring-buffer such as ftrace_printk could occurred
+ * insertions into the ring-buffer such as trace_printk could occurred
* at the same time, giving false positive or negative results.
*/
static bool __read_mostly tracing_selftest_running;
* of the tracer is successful. But that is the only place that sets
* this back to zero.
*/
-int tracing_disabled = 1;
+static int tracing_disabled = 1;
static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
static cpumask_var_t __read_mostly tracing_buffer_mask;
+/* Define which cpu buffers are currently read in trace_pipe */
+static cpumask_var_t tracing_reader_cpumask;
+
#define for_each_tracing_cpu(cpu) \
for_each_cpu(cpu, tracing_buffer_mask)
{
strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
+ /* We are using ftrace early, expand it */
+ ring_buffer_expanded = 1;
return 1;
}
__setup("ftrace=", set_ftrace);
}
__setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops);
-long
-ns2usecs(cycle_t nsec)
+unsigned long long ns2usecs(cycle_t nsec)
{
nsec += 500;
do_div(nsec, 1000);
return nsec;
}
-cycle_t ftrace_now(int cpu)
-{
- u64 ts = ring_buffer_time_stamp(cpu);
- ring_buffer_normalize_time_stamp(cpu, &ts);
- return ts;
-}
-
/*
* The global_trace is the descriptor that holds the tracing
* buffers for the live tracing. For each CPU, it contains
static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu);
+cycle_t ftrace_now(int cpu)
+{
+ u64 ts;
+
+ /* Early boot up does not have a buffer yet */
+ if (!global_trace.buffer)
+ return trace_clock_local();
+
+ ts = ring_buffer_time_stamp(global_trace.buffer, cpu);
+ ring_buffer_normalize_time_stamp(global_trace.buffer, cpu, &ts);
+
+ return ts;
+}
+
/*
* The max_tr is used to snapshot the global_trace when a maximum
* latency is reached. Some tracers will use this to store a maximum
/* trace_flags holds trace_options default values */
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
- TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO;
+ TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME;
/**
* trace_wake_up - wake up tasks waiting for trace input
"block",
"stacktrace",
"sched-tree",
- "ftrace_printk",
+ "trace_printk",
"ftrace_preempt",
"branch",
"annotate",
"sym-userobj",
"printk-msg-only",
"context-info",
+ "latency-format",
+ "global-clock",
+ "sleep-time",
NULL
};
data->rt_priority = tsk->rt_priority;
/* record this tasks comm */
- tracing_record_cmdline(current);
-}
-
-static void
-trace_seq_reset(struct trace_seq *s)
-{
- s->len = 0;
- s->readpos = 0;
+ tracing_record_cmdline(tsk);
}
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt)
int len;
int ret;
+ if (!cnt)
+ return 0;
+
if (s->len <= s->readpos)
return -EBUSY;
if (cnt > len)
cnt = len;
ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt);
- if (ret)
+ if (ret == cnt)
return -EFAULT;
- s->readpos += len;
+ cnt -= ret;
+
+ s->readpos += cnt;
return cnt;
}
-ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
+static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt)
{
int len;
void *ret;
if (!ret)
return -EFAULT;
- s->readpos += len;
+ s->readpos += cnt;
return cnt;
}
s->buffer[len] = 0;
seq_puts(m, s->buffer);
- trace_seq_reset(s);
+ trace_seq_init(s);
}
/**
* Register a new plugin tracer.
*/
int register_tracer(struct tracer *type)
+__releases(kernel_lock)
+__acquires(kernel_lock)
{
struct tracer *t;
int len;
else
if (!type->flags->opts)
type->flags->opts = dummy_tracer_opt;
+ if (!type->wait_pipe)
+ type->wait_pipe = default_wait_pipe;
+
#ifdef CONFIG_FTRACE_STARTUP_TEST
if (type->selftest && !tracing_selftest_disabled) {
}
#define SAVED_CMDLINES 128
+#define NO_CMDLINE_MAP UINT_MAX
static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1];
static unsigned map_cmdline_to_pid[SAVED_CMDLINES];
static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN];
static int cmdline_idx;
-static DEFINE_SPINLOCK(trace_cmdline_lock);
+static raw_spinlock_t trace_cmdline_lock = __RAW_SPIN_LOCK_UNLOCKED;
/* temporary disable recording */
-atomic_t trace_record_cmdline_disabled __read_mostly;
+static atomic_t trace_record_cmdline_disabled __read_mostly;
static void trace_init_cmdlines(void)
{
- memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline));
- memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid));
+ memset(&map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(map_pid_to_cmdline));
+ memset(&map_cmdline_to_pid, NO_CMDLINE_MAP, sizeof(map_cmdline_to_pid));
cmdline_idx = 0;
}
static void trace_save_cmdline(struct task_struct *tsk)
{
- unsigned map;
- unsigned idx;
+ unsigned pid, idx;
if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT))
return;
* nor do we want to disable interrupts,
* so if we miss here, then better luck next time.
*/
- if (!spin_trylock(&trace_cmdline_lock))
+ if (!__raw_spin_trylock(&trace_cmdline_lock))
return;
idx = map_pid_to_cmdline[tsk->pid];
- if (idx >= SAVED_CMDLINES) {
+ if (idx == NO_CMDLINE_MAP) {
idx = (cmdline_idx + 1) % SAVED_CMDLINES;
- map = map_cmdline_to_pid[idx];
- if (map <= PID_MAX_DEFAULT)
- map_pid_to_cmdline[map] = (unsigned)-1;
+ /*
+ * Check whether the cmdline buffer at idx has a pid
+ * mapped. We are going to overwrite that entry so we
+ * need to clear the map_pid_to_cmdline. Otherwise we
+ * would read the new comm for the old pid.
+ */
+ pid = map_cmdline_to_pid[idx];
+ if (pid != NO_CMDLINE_MAP)
+ map_pid_to_cmdline[pid] = NO_CMDLINE_MAP;
+ map_cmdline_to_pid[idx] = tsk->pid;
map_pid_to_cmdline[tsk->pid] = idx;
cmdline_idx = idx;
memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN);
- spin_unlock(&trace_cmdline_lock);
+ __raw_spin_unlock(&trace_cmdline_lock);
}
-char *trace_find_cmdline(int pid)
+void trace_find_cmdline(int pid, char comm[])
{
- char *cmdline = "<...>";
unsigned map;
- if (!pid)
- return "<idle>";
+ if (!pid) {
+ strcpy(comm, "<idle>");
+ return;
+ }
- if (pid > PID_MAX_DEFAULT)
- goto out;
+ if (pid > PID_MAX_DEFAULT) {
+ strcpy(comm, "<...>");
+ return;
+ }
+ __raw_spin_lock(&trace_cmdline_lock);
map = map_pid_to_cmdline[pid];
- if (map >= SAVED_CMDLINES)
- goto out;
-
- cmdline = saved_cmdlines[map];
+ if (map != NO_CMDLINE_MAP)
+ strcpy(comm, saved_cmdlines[map]);
+ else
+ strcpy(comm, "<...>");
- out:
- return cmdline;
+ __raw_spin_unlock(&trace_cmdline_lock);
}
void tracing_record_cmdline(struct task_struct *tsk)
{
- if (atomic_read(&trace_record_cmdline_disabled))
+ if (atomic_read(&trace_record_cmdline_disabled) || !tracer_enabled ||
+ !tracing_is_on())
return;
trace_save_cmdline(tsk);
entry->preempt_count = pc & 0xff;
entry->pid = (tsk) ? tsk->pid : 0;
- entry->tgid = (tsk) ? tsk->tgid : 0;
+ entry->tgid = (tsk) ? tsk->tgid : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
static void ftrace_trace_userstack(struct trace_array *tr,
unsigned long flags, int pc);
-void trace_buffer_unlock_commit(struct trace_array *tr,
- struct ring_buffer_event *event,
- unsigned long flags, int pc)
+static inline void __trace_buffer_unlock_commit(struct trace_array *tr,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc,
+ int wake)
{
ring_buffer_unlock_commit(tr->buffer, event);
ftrace_trace_stack(tr, flags, 6, pc);
ftrace_trace_userstack(tr, flags, pc);
- trace_wake_up();
+
+ if (wake)
+ trace_wake_up();
+}
+
+void trace_buffer_unlock_commit(struct trace_array *tr,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc)
+{
+ __trace_buffer_unlock_commit(tr, event, flags, pc, 1);
+}
+
+struct ring_buffer_event *
+trace_current_buffer_lock_reserve(unsigned char type, unsigned long len,
+ unsigned long flags, int pc)
+{
+ return trace_buffer_lock_reserve(&global_trace,
+ type, len, flags, pc);
+}
+
+void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
+ unsigned long flags, int pc)
+{
+ return __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 1);
+}
+
+void trace_nowake_buffer_unlock_commit(struct ring_buffer_event *event,
+ unsigned long flags, int pc)
+{
+ return __trace_buffer_unlock_commit(&global_trace, event, flags, pc, 0);
}
void
}
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static void __trace_graph_entry(struct trace_array *tr,
+static int __trace_graph_entry(struct trace_array *tr,
struct ftrace_graph_ent *trace,
unsigned long flags,
int pc)
struct ftrace_graph_ent_entry *entry;
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
- return;
+ return 0;
event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
sizeof(*entry), flags, pc);
if (!event)
- return;
+ return 0;
entry = ring_buffer_event_data(event);
entry->graph_ent = *trace;
ring_buffer_unlock_commit(global_trace.buffer, event);
+
+ return 1;
}
static void __trace_graph_return(struct trace_array *tr,
#endif
}
-void __trace_userstack(struct trace_array *tr, unsigned long flags)
+#ifdef UNUSED
+static void __trace_userstack(struct trace_array *tr, unsigned long flags)
{
ftrace_trace_userstack(tr, flags, preempt_count());
}
+#endif /* UNUSED */
static void
ftrace_trace_special(void *__tr,
entry->next_prio = wakee->prio;
entry->next_state = wakee->state;
entry->next_cpu = task_cpu(wakee);
- trace_buffer_unlock_commit(tr, event, flags, pc);
+
+ ring_buffer_unlock_commit(tr->buffer, event);
+ ftrace_trace_stack(tr, flags, 6, pc);
+ ftrace_trace_userstack(tr, flags, pc);
}
void
struct trace_array_cpu *data;
unsigned long flags;
long disabled;
+ int ret;
int cpu;
int pc;
disabled = atomic_inc_return(&data->disabled);
if (likely(disabled == 1)) {
pc = preempt_count();
- __trace_graph_entry(tr, trace, flags, pc);
+ ret = __trace_graph_entry(tr, trace, flags, pc);
+ } else {
+ ret = 0;
}
/* Only do the atomic if it is not already set */
if (!test_tsk_trace_graph(current))
set_tsk_trace_graph(current);
+
atomic_dec(&data->disabled);
local_irq_restore(flags);
- return 1;
+ return ret;
}
void trace_graph_return(struct ftrace_graph_ret *trace)
}
#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
+
+/**
+ * trace_vbprintk - write binary msg to tracing buffer
+ *
+ */
+int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
+{
+ static raw_spinlock_t trace_buf_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+ static u32 trace_buf[TRACE_BUF_SIZE];
+
+ struct ring_buffer_event *event;
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ struct bprint_entry *entry;
+ unsigned long flags;
+ int resched;
+ int cpu, len = 0, size, pc;
+
+ if (unlikely(tracing_selftest_running || tracing_disabled))
+ return 0;
+
+ /* Don't pollute graph traces with trace_vprintk internals */
+ pause_graph_tracing();
+
+ pc = preempt_count();
+ resched = ftrace_preempt_disable();
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+
+ if (unlikely(atomic_read(&data->disabled)))
+ goto out;
+
+ /* Lockdep uses trace_printk for lock tracing */
+ local_irq_save(flags);
+ __raw_spin_lock(&trace_buf_lock);
+ len = vbin_printf(trace_buf, TRACE_BUF_SIZE, fmt, args);
+
+ if (len > TRACE_BUF_SIZE || len < 0)
+ goto out_unlock;
+
+ size = sizeof(*entry) + sizeof(u32) * len;
+ event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc);
+ if (!event)
+ goto out_unlock;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+ entry->fmt = fmt;
+
+ memcpy(entry->buf, trace_buf, sizeof(u32) * len);
+ ring_buffer_unlock_commit(tr->buffer, event);
+
+out_unlock:
+ __raw_spin_unlock(&trace_buf_lock);
+ local_irq_restore(flags);
+
+out:
+ ftrace_preempt_enable(resched);
+ unpause_graph_tracing();
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(trace_vbprintk);
+
+int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+{
+ static raw_spinlock_t trace_buf_lock = __RAW_SPIN_LOCK_UNLOCKED;
+ static char trace_buf[TRACE_BUF_SIZE];
+
+ struct ring_buffer_event *event;
+ struct trace_array *tr = &global_trace;
+ struct trace_array_cpu *data;
+ int cpu, len = 0, size, pc;
+ struct print_entry *entry;
+ unsigned long irq_flags;
+
+ if (tracing_disabled || tracing_selftest_running)
+ return 0;
+
+ pc = preempt_count();
+ preempt_disable_notrace();
+ cpu = raw_smp_processor_id();
+ data = tr->data[cpu];
+
+ if (unlikely(atomic_read(&data->disabled)))
+ goto out;
+
+ pause_graph_tracing();
+ raw_local_irq_save(irq_flags);
+ __raw_spin_lock(&trace_buf_lock);
+ len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
+
+ len = min(len, TRACE_BUF_SIZE-1);
+ trace_buf[len] = 0;
+
+ size = sizeof(*entry) + len + 1;
+ event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
+ if (!event)
+ goto out_unlock;
+ entry = ring_buffer_event_data(event);
+ entry->ip = ip;
+
+ memcpy(&entry->buf, trace_buf, len);
+ entry->buf[len] = 0;
+ ring_buffer_unlock_commit(tr->buffer, event);
+
+ out_unlock:
+ __raw_spin_unlock(&trace_buf_lock);
+ raw_local_irq_restore(irq_flags);
+ unpause_graph_tracing();
+ out:
+ preempt_enable_notrace();
+
+ return len;
+}
+EXPORT_SYMBOL_GPL(trace_vprintk);
+
enum trace_file_type {
TRACE_FILE_LAT_FMT = 1,
TRACE_FILE_ANNOTATE = 2,
{
struct ring_buffer *buffer = iter->tr->buffer;
struct trace_entry *ent, *next = NULL;
+ int cpu_file = iter->cpu_file;
u64 next_ts = 0, ts;
int next_cpu = -1;
int cpu;
+ /*
+ * If we are in a per_cpu trace file, don't bother by iterating over
+ * all cpu and peek directly.
+ */
+ if (cpu_file > TRACE_PIPE_ALL_CPU) {
+ if (ring_buffer_empty_cpu(buffer, cpu_file))
+ return NULL;
+ ent = peek_next_entry(iter, cpu_file, ent_ts);
+ if (ent_cpu)
+ *ent_cpu = cpu_file;
+
+ return ent;
+ }
+
for_each_tracing_cpu(cpu) {
if (ring_buffer_empty_cpu(buffer, cpu))
return ent;
}
+/*
+ * No necessary locking here. The worst thing which can
+ * happen is loosing events consumed at the same time
+ * by a trace_pipe reader.
+ * Other than that, we don't risk to crash the ring buffer
+ * because it serializes the readers.
+ *
+ * The current tracer is copied to avoid a global locking
+ * all around.
+ */
static void *s_start(struct seq_file *m, loff_t *pos)
{
struct trace_iterator *iter = m->private;
+ static struct tracer *old_tracer;
+ int cpu_file = iter->cpu_file;
void *p = NULL;
loff_t l = 0;
int cpu;
+ /* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
-
- if (!current_trace || current_trace != iter->trace) {
- mutex_unlock(&trace_types_lock);
- return NULL;
+ if (unlikely(old_tracer != current_trace && current_trace)) {
+ old_tracer = current_trace;
+ *iter->trace = *current_trace;
}
+ mutex_unlock(&trace_types_lock);
atomic_inc(&trace_record_cmdline_disabled);
ftrace_disable_cpu();
- for_each_tracing_cpu(cpu) {
- ring_buffer_iter_reset(iter->buffer_iter[cpu]);
- }
+ if (cpu_file == TRACE_PIPE_ALL_CPU) {
+ for_each_tracing_cpu(cpu)
+ ring_buffer_iter_reset(iter->buffer_iter[cpu]);
+ } else
+ ring_buffer_iter_reset(iter->buffer_iter[cpu_file]);
+
ftrace_enable_cpu();
static void s_stop(struct seq_file *m, void *p)
{
atomic_dec(&trace_record_cmdline_disabled);
- mutex_unlock(&trace_types_lock);
}
static void print_lat_help_header(struct seq_file *m)
total = entries +
ring_buffer_overruns(iter->tr->buffer);
- seq_printf(m, "%s latency trace v1.1.5 on %s\n",
+ seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
name, UTS_RELEASE);
- seq_puts(m, "-----------------------------------"
+ seq_puts(m, "# -----------------------------------"
"---------------------------------\n");
- seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |"
+ seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |"
" (M:%s VP:%d, KP:%d, SP:%d HP:%d",
nsecs_to_usecs(data->saved_latency),
entries,
#else
seq_puts(m, ")\n");
#endif
- seq_puts(m, " -----------------\n");
- seq_printf(m, " | task: %.16s-%d "
+ seq_puts(m, "# -----------------\n");
+ seq_printf(m, "# | task: %.16s-%d "
"(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n",
data->comm, data->pid, data->uid, data->nice,
data->policy, data->rt_priority);
- seq_puts(m, " -----------------\n");
+ seq_puts(m, "# -----------------\n");
if (data->critical_start) {
- seq_puts(m, " => started at: ");
+ seq_puts(m, "# => started at: ");
seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags);
trace_print_seq(m, &iter->seq);
- seq_puts(m, "\n => ended at: ");
+ seq_puts(m, "\n# => ended at: ");
seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags);
trace_print_seq(m, &iter->seq);
- seq_puts(m, "\n");
+ seq_puts(m, "#\n");
}
- seq_puts(m, "\n");
+ seq_puts(m, "#\n");
}
static void test_cpu_buff_start(struct trace_iterator *iter)
return;
cpumask_set_cpu(iter->cpu, iter->started);
- trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu);
-}
-
-static enum print_line_t print_lat_fmt(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK);
- struct trace_event *event;
- struct trace_entry *entry = iter->ent;
-
- test_cpu_buff_start(iter);
-
- event = ftrace_find_event(entry->type);
-
- if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
- if (!trace_print_lat_context(iter))
- goto partial;
- }
-
- if (event)
- return event->latency_trace(iter, sym_flags);
-
- if (!trace_seq_printf(s, "Unknown type %d\n", entry->type))
- goto partial;
- return TRACE_TYPE_HANDLED;
-partial:
- return TRACE_TYPE_PARTIAL_LINE;
+ /* Don't print started cpu buffer for the first entry of the trace */
+ if (iter->idx > 1)
+ trace_seq_printf(s, "##### CPU %u buffer started ####\n",
+ iter->cpu);
}
static enum print_line_t print_trace_fmt(struct trace_iterator *iter)
event = ftrace_find_event(entry->type);
if (trace_flags & TRACE_ITER_CONTEXT_INFO) {
- if (!trace_print_context(iter))
- goto partial;
+ if (iter->iter_flags & TRACE_FILE_LAT_FMT) {
+ if (!trace_print_lat_context(iter))
+ goto partial;
+ } else {
+ if (!trace_print_context(iter))
+ goto partial;
+ }
}
if (event)
return TRACE_TYPE_HANDLED;
}
-static enum print_line_t print_printk_msg_only(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- struct trace_entry *entry = iter->ent;
- struct print_entry *field;
- int ret;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_printf(s, "%s", field->buf);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- return TRACE_TYPE_HANDLED;
-}
-
static enum print_line_t print_bin_fmt(struct trace_iterator *iter)
{
struct trace_seq *s = &iter->seq;
{
int cpu;
+ /* If we are looking at one CPU buffer, only check that one */
+ if (iter->cpu_file != TRACE_PIPE_ALL_CPU) {
+ cpu = iter->cpu_file;
+ if (iter->buffer_iter[cpu]) {
+ if (!ring_buffer_iter_empty(iter->buffer_iter[cpu]))
+ return 0;
+ } else {
+ if (!ring_buffer_empty_cpu(iter->tr->buffer, cpu))
+ return 0;
+ }
+ return 1;
+ }
+
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu]) {
if (!ring_buffer_iter_empty(iter->buffer_iter[cpu]))
return ret;
}
+ if (iter->ent->type == TRACE_BPRINT &&
+ trace_flags & TRACE_ITER_PRINTK &&
+ trace_flags & TRACE_ITER_PRINTK_MSGONLY)
+ return trace_print_bprintk_msg_only(iter);
+
if (iter->ent->type == TRACE_PRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
- return print_printk_msg_only(iter);
+ return trace_print_printk_msg_only(iter);
if (trace_flags & TRACE_ITER_BIN)
return print_bin_fmt(iter);
if (trace_flags & TRACE_ITER_RAW)
return print_raw_fmt(iter);
- if (iter->iter_flags & TRACE_FILE_LAT_FMT)
- return print_lat_fmt(iter);
-
return print_trace_fmt(iter);
}
};
static struct trace_iterator *
-__tracing_open(struct inode *inode, struct file *file, int *ret)
+__tracing_open(struct inode *inode, struct file *file)
{
+ long cpu_file = (long) inode->i_private;
+ void *fail_ret = ERR_PTR(-ENOMEM);
struct trace_iterator *iter;
struct seq_file *m;
- int cpu;
+ int cpu, ret;
- if (tracing_disabled) {
- *ret = -ENODEV;
- return NULL;
- }
+ if (tracing_disabled)
+ return ERR_PTR(-ENODEV);
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
- if (!iter) {
- *ret = -ENOMEM;
- goto out;
- }
+ if (!iter)
+ return ERR_PTR(-ENOMEM);
+ /*
+ * We make a copy of the current tracer to avoid concurrent
+ * changes on it while we are reading.
+ */
mutex_lock(&trace_types_lock);
+ iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL);
+ if (!iter->trace)
+ goto fail;
+
+ if (current_trace)
+ *iter->trace = *current_trace;
+
+ if (!alloc_cpumask_var(&iter->started, GFP_KERNEL))
+ goto fail;
+
+ cpumask_clear(iter->started);
+
if (current_trace && current_trace->print_max)
iter->tr = &max_tr;
else
- iter->tr = inode->i_private;
- iter->trace = current_trace;
+ iter->tr = &global_trace;
iter->pos = -1;
+ mutex_init(&iter->mutex);
+ iter->cpu_file = cpu_file;
/* Notify the tracer early; before we stop tracing. */
if (iter->trace && iter->trace->open)
if (ring_buffer_overruns(iter->tr->buffer))
iter->iter_flags |= TRACE_FILE_ANNOTATE;
+ if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
+ for_each_tracing_cpu(cpu) {
- for_each_tracing_cpu(cpu) {
-
+ iter->buffer_iter[cpu] =
+ ring_buffer_read_start(iter->tr->buffer, cpu);
+ }
+ } else {
+ cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
- ring_buffer_read_start(iter->tr->buffer, cpu);
-
- if (!iter->buffer_iter[cpu])
- goto fail_buffer;
+ ring_buffer_read_start(iter->tr->buffer, cpu);
}
/* TODO stop tracer */
- *ret = seq_open(file, &tracer_seq_ops);
- if (*ret)
+ ret = seq_open(file, &tracer_seq_ops);
+ if (ret < 0) {
+ fail_ret = ERR_PTR(ret);
goto fail_buffer;
+ }
m = file->private_data;
m->private = iter;
mutex_unlock(&trace_types_lock);
- out:
return iter;
fail_buffer:
if (iter->buffer_iter[cpu])
ring_buffer_read_finish(iter->buffer_iter[cpu]);
}
+ free_cpumask_var(iter->started);
+ fail:
mutex_unlock(&trace_types_lock);
+ kfree(iter->trace);
kfree(iter);
- return ERR_PTR(-ENOMEM);
+ return fail_ret;
}
int tracing_open_generic(struct inode *inode, struct file *filp)
return 0;
}
-int tracing_release(struct inode *inode, struct file *file)
+static int tracing_release(struct inode *inode, struct file *file)
{
struct seq_file *m = (struct seq_file *)file->private_data;
- struct trace_iterator *iter = m->private;
+ struct trace_iterator *iter;
int cpu;
+ if (!(file->f_mode & FMODE_READ))
+ return 0;
+
+ iter = m->private;
+
mutex_lock(&trace_types_lock);
for_each_tracing_cpu(cpu) {
if (iter->buffer_iter[cpu])
mutex_unlock(&trace_types_lock);
seq_release(inode, file);
+ mutex_destroy(&iter->mutex);
+ free_cpumask_var(iter->started);
+ kfree(iter->trace);
kfree(iter);
return 0;
}
static int tracing_open(struct inode *inode, struct file *file)
{
- int ret;
-
- __tracing_open(inode, file, &ret);
-
- return ret;
-}
-
-static int tracing_lt_open(struct inode *inode, struct file *file)
-{
struct trace_iterator *iter;
- int ret;
+ int ret = 0;
- iter = __tracing_open(inode, file, &ret);
+ /* If this file was open for write, then erase contents */
+ if ((file->f_mode & FMODE_WRITE) &&
+ !(file->f_flags & O_APPEND)) {
+ long cpu = (long) inode->i_private;
- if (!ret)
- iter->iter_flags |= TRACE_FILE_LAT_FMT;
+ if (cpu == TRACE_PIPE_ALL_CPU)
+ tracing_reset_online_cpus(&global_trace);
+ else
+ tracing_reset(&global_trace, cpu);
+ }
+ if (file->f_mode & FMODE_READ) {
+ iter = __tracing_open(inode, file);
+ if (IS_ERR(iter))
+ ret = PTR_ERR(iter);
+ else if (trace_flags & TRACE_ITER_LATENCY_FMT)
+ iter->iter_flags |= TRACE_FILE_LAT_FMT;
+ }
return ret;
}
-
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
return ret;
}
-static struct file_operations tracing_fops = {
- .open = tracing_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = tracing_release,
-};
+static ssize_t
+tracing_write_stub(struct file *filp, const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ return count;
+}
-static struct file_operations tracing_lt_fops = {
- .open = tracing_lt_open,
+static const struct file_operations tracing_fops = {
+ .open = tracing_open,
.read = seq_read,
+ .write = tracing_write_stub,
.llseek = seq_lseek,
.release = tracing_release,
};
-static struct file_operations show_traces_fops = {
+static const struct file_operations show_traces_fops = {
.open = show_traces_open,
.read = seq_read,
.release = seq_release,
return err;
}
-static struct file_operations tracing_cpumask_fops = {
+static const struct file_operations tracing_cpumask_fops = {
.open = tracing_open_generic,
.read = tracing_cpumask_read,
.write = tracing_cpumask_write,
tracing_trace_options_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- int i;
+ struct tracer_opt *trace_opts;
+ u32 tracer_flags;
+ int len = 0;
char *buf;
int r = 0;
- int len = 0;
- u32 tracer_flags = current_trace->flags->val;
- struct tracer_opt *trace_opts = current_trace->flags->opts;
+ int i;
- /* calulate max size */
+ /* calculate max size */
for (i = 0; trace_options[i]; i++) {
len += strlen(trace_options[i]);
- len += 3; /* "no" and space */
+ len += 3; /* "no" and newline */
}
+ mutex_lock(&trace_types_lock);
+ tracer_flags = current_trace->flags->val;
+ trace_opts = current_trace->flags->opts;
+
/*
* Increase the size with names of options specific
* of the current tracer.
*/
for (i = 0; trace_opts[i].name; i++) {
len += strlen(trace_opts[i].name);
- len += 3; /* "no" and space */
+ len += 3; /* "no" and newline */
}
/* +2 for \n and \0 */
buf = kmalloc(len + 2, GFP_KERNEL);
- if (!buf)
+ if (!buf) {
+ mutex_unlock(&trace_types_lock);
return -ENOMEM;
+ }
for (i = 0; trace_options[i]; i++) {
if (trace_flags & (1 << i))
- r += sprintf(buf + r, "%s ", trace_options[i]);
+ r += sprintf(buf + r, "%s\n", trace_options[i]);
else
- r += sprintf(buf + r, "no%s ", trace_options[i]);
+ r += sprintf(buf + r, "no%s\n", trace_options[i]);
}
for (i = 0; trace_opts[i].name; i++) {
if (tracer_flags & trace_opts[i].bit)
- r += sprintf(buf + r, "%s ",
+ r += sprintf(buf + r, "%s\n",
trace_opts[i].name);
else
- r += sprintf(buf + r, "no%s ",
+ r += sprintf(buf + r, "no%s\n",
trace_opts[i].name);
}
+ mutex_unlock(&trace_types_lock);
- r += sprintf(buf + r, "\n");
WARN_ON(r >= len + 2);
r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
kfree(buf);
-
return r;
}
return 0;
}
+static void set_tracer_flags(unsigned int mask, int enabled)
+{
+ /* do nothing if flag is already set */
+ if (!!(trace_flags & mask) == !!enabled)
+ return;
+
+ if (enabled)
+ trace_flags |= mask;
+ else
+ trace_flags &= ~mask;
+
+ if (mask == TRACE_ITER_GLOBAL_CLK) {
+ u64 (*func)(void);
+
+ if (enabled)
+ func = trace_clock_global;
+ else
+ func = trace_clock_local;
+
+ mutex_lock(&trace_types_lock);
+ ring_buffer_set_clock(global_trace.buffer, func);
+
+ if (max_tr.buffer)
+ ring_buffer_set_clock(max_tr.buffer, func);
+ mutex_unlock(&trace_types_lock);
+ }
+}
+
static ssize_t
tracing_trace_options_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
int len = strlen(trace_options[i]);
if (strncmp(cmp, trace_options[i], len) == 0) {
- if (neg)
- trace_flags &= ~(1 << i);
- else
- trace_flags |= (1 << i);
+ set_tracer_flags(1 << i, !neg);
break;
}
}
/* If no option could be set, test the specific tracer options */
if (!trace_options[i]) {
+ mutex_lock(&trace_types_lock);
ret = set_tracer_option(current_trace, cmp, neg);
+ mutex_unlock(&trace_types_lock);
if (ret)
return ret;
}
return cnt;
}
-static struct file_operations tracing_iter_fops = {
+static const struct file_operations tracing_iter_fops = {
.open = tracing_open_generic,
.read = tracing_trace_options_read,
.write = tracing_trace_options_write,
"# mkdir /debug\n"
"# mount -t debugfs nodev /debug\n\n"
"# cat /debug/tracing/available_tracers\n"
- "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n"
+ "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
"# cat /debug/tracing/current_tracer\n"
- "none\n"
+ "nop\n"
"# echo sched_switch > /debug/tracing/current_tracer\n"
"# cat /debug/tracing/current_tracer\n"
"sched_switch\n"
readme_msg, strlen(readme_msg));
}
-static struct file_operations tracing_readme_fops = {
+static const struct file_operations tracing_readme_fops = {
.open = tracing_open_generic,
.read = tracing_readme_read,
};
{
struct trace_array *tr = filp->private_data;
char buf[64];
- long val;
+ unsigned long val;
int ret;
if (cnt >= sizeof(buf))
return t->init(tr);
}
+static int tracing_resize_ring_buffer(unsigned long size)
+{
+ int ret;
+
+ /*
+ * If kernel or user changes the size of the ring buffer
+ * we use the size that was given, and we can forget about
+ * expanding it later.
+ */
+ ring_buffer_expanded = 1;
+
+ ret = ring_buffer_resize(global_trace.buffer, size);
+ if (ret < 0)
+ return ret;
+
+ ret = ring_buffer_resize(max_tr.buffer, size);
+ if (ret < 0) {
+ int r;
+
+ r = ring_buffer_resize(global_trace.buffer,
+ global_trace.entries);
+ if (r < 0) {
+ /*
+ * AARGH! We are left with different
+ * size max buffer!!!!
+ * The max buffer is our "snapshot" buffer.
+ * When a tracer needs a snapshot (one of the
+ * latency tracers), it swaps the max buffer
+ * with the saved snap shot. We succeeded to
+ * update the size of the main buffer, but failed to
+ * update the size of the max buffer. But when we tried
+ * to reset the main buffer to the original size, we
+ * failed there too. This is very unlikely to
+ * happen, but if it does, warn and kill all
+ * tracing.
+ */
+ WARN_ON(1);
+ tracing_disabled = 1;
+ }
+ return ret;
+ }
+
+ global_trace.entries = size;
+
+ return ret;
+}
+
+/**
+ * tracing_update_buffers - used by tracing facility to expand ring buffers
+ *
+ * To save on memory when the tracing is never used on a system with it
+ * configured in. The ring buffers are set to a minimum size. But once
+ * a user starts to use the tracing facility, then they need to grow
+ * to their default size.
+ *
+ * This function is to be called when a tracer is about to be used.
+ */
+int tracing_update_buffers(void)
+{
+ int ret = 0;
+
+ mutex_lock(&trace_types_lock);
+ if (!ring_buffer_expanded)
+ ret = tracing_resize_ring_buffer(trace_buf_size);
+ mutex_unlock(&trace_types_lock);
+
+ return ret;
+}
+
+struct trace_option_dentry;
+
+static struct trace_option_dentry *
+create_trace_option_files(struct tracer *tracer);
+
+static void
+destroy_trace_option_files(struct trace_option_dentry *topts);
+
static int tracing_set_tracer(const char *buf)
{
+ static struct trace_option_dentry *topts;
struct trace_array *tr = &global_trace;
struct tracer *t;
int ret = 0;
mutex_lock(&trace_types_lock);
+
+ if (!ring_buffer_expanded) {
+ ret = tracing_resize_ring_buffer(trace_buf_size);
+ if (ret < 0)
+ goto out;
+ ret = 0;
+ }
+
for (t = trace_types; t; t = t->next) {
if (strcmp(t->name, buf) == 0)
break;
if (current_trace && current_trace->reset)
current_trace->reset(tr);
+ destroy_trace_option_files(topts);
+
current_trace = t;
+
+ topts = create_trace_option_files(current_trace);
+
if (t->init) {
ret = tracer_init(t, tr);
if (ret)
tracing_max_lat_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- long *ptr = filp->private_data;
+ unsigned long *ptr = filp->private_data;
char buf[64];
- long val;
+ unsigned long val;
int ret;
if (cnt >= sizeof(buf))
return cnt;
}
-static atomic_t tracing_reader;
-
static int tracing_open_pipe(struct inode *inode, struct file *filp)
{
+ long cpu_file = (long) inode->i_private;
struct trace_iterator *iter;
+ int ret = 0;
if (tracing_disabled)
return -ENODEV;
- /* We only allow for reader of the pipe */
- if (atomic_inc_return(&tracing_reader) != 1) {
- atomic_dec(&tracing_reader);
- return -EBUSY;
+ mutex_lock(&trace_types_lock);
+
+ /* We only allow one reader per cpu */
+ if (cpu_file == TRACE_PIPE_ALL_CPU) {
+ if (!cpumask_empty(tracing_reader_cpumask)) {
+ ret = -EBUSY;
+ goto out;
+ }
+ cpumask_setall(tracing_reader_cpumask);
+ } else {
+ if (!cpumask_test_cpu(cpu_file, tracing_reader_cpumask))
+ cpumask_set_cpu(cpu_file, tracing_reader_cpumask);
+ else {
+ ret = -EBUSY;
+ goto out;
+ }
}
/* create a buffer to store the information to pass to userspace */
iter = kzalloc(sizeof(*iter), GFP_KERNEL);
- if (!iter)
- return -ENOMEM;
+ if (!iter) {
+ ret = -ENOMEM;
+ goto out;
+ }
- if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) {
- kfree(iter);
- return -ENOMEM;
+ /*
+ * We make a copy of the current tracer to avoid concurrent
+ * changes on it while we are reading.
+ */
+ iter->trace = kmalloc(sizeof(*iter->trace), GFP_KERNEL);
+ if (!iter->trace) {
+ ret = -ENOMEM;
+ goto fail;
}
+ if (current_trace)
+ *iter->trace = *current_trace;
- mutex_lock(&trace_types_lock);
+ if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) {
+ ret = -ENOMEM;
+ goto fail;
+ }
/* trace pipe does not show start of buffer */
cpumask_setall(iter->started);
+ iter->cpu_file = cpu_file;
iter->tr = &global_trace;
- iter->trace = current_trace;
+ mutex_init(&iter->mutex);
filp->private_data = iter;
if (iter->trace->pipe_open)
iter->trace->pipe_open(iter);
+
+out:
mutex_unlock(&trace_types_lock);
+ return ret;
- return 0;
+fail:
+ kfree(iter->trace);
+ kfree(iter);
+ mutex_unlock(&trace_types_lock);
+ return ret;
}
static int tracing_release_pipe(struct inode *inode, struct file *file)
{
struct trace_iterator *iter = file->private_data;
+ mutex_lock(&trace_types_lock);
+
+ if (iter->cpu_file == TRACE_PIPE_ALL_CPU)
+ cpumask_clear(tracing_reader_cpumask);
+ else
+ cpumask_clear_cpu(iter->cpu_file, tracing_reader_cpumask);
+
+ mutex_unlock(&trace_types_lock);
+
free_cpumask_var(iter->started);
+ mutex_destroy(&iter->mutex);
+ kfree(iter->trace);
kfree(iter);
- atomic_dec(&tracing_reader);
return 0;
}
}
}
+
+void default_wait_pipe(struct trace_iterator *iter)
+{
+ DEFINE_WAIT(wait);
+
+ prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
+
+ if (trace_empty(iter))
+ schedule();
+
+ finish_wait(&trace_wait, &wait);
+}
+
+/*
+ * This is a make-shift waitqueue.
+ * A tracer might use this callback on some rare cases:
+ *
+ * 1) the current tracer might hold the runqueue lock when it wakes up
+ * a reader, hence a deadlock (sched, function, and function graph tracers)
+ * 2) the function tracers, trace all functions, we don't want
+ * the overhead of calling wake_up and friends
+ * (and tracing them too)
+ *
+ * Anyway, this is really very primitive wakeup.
+ */
+void poll_wait_pipe(struct trace_iterator *iter)
+{
+ set_current_state(TASK_INTERRUPTIBLE);
+ /* sleep for 100 msecs, and try again. */
+ schedule_timeout(HZ / 10);
+}
+
/* Must be called with trace_types_lock mutex held. */
static int tracing_wait_pipe(struct file *filp)
{
return -EAGAIN;
}
- /*
- * This is a make-shift waitqueue. The reason we don't use
- * an actual wait queue is because:
- * 1) we only ever have one waiter
- * 2) the tracing, traces all functions, we don't want
- * the overhead of calling wake_up and friends
- * (and tracing them too)
- * Anyway, this is really very primitive wakeup.
- */
- set_current_state(TASK_INTERRUPTIBLE);
- iter->tr->waiter = current;
-
- mutex_unlock(&trace_types_lock);
-
- /* sleep for 100 msecs, and try again. */
- schedule_timeout(HZ/10);
+ mutex_unlock(&iter->mutex);
- mutex_lock(&trace_types_lock);
+ iter->trace->wait_pipe(iter);
- iter->tr->waiter = NULL;
+ mutex_lock(&iter->mutex);
- if (signal_pending(current)) {
+ if (signal_pending(current))
return -EINTR;
- }
-
- if (iter->trace != current_trace)
- return 0;
/*
* We block until we read something and tracing is disabled.
*/
if (!tracer_enabled && iter->pos)
break;
-
- continue;
}
return 1;
size_t cnt, loff_t *ppos)
{
struct trace_iterator *iter = filp->private_data;
+ static struct tracer *old_tracer;
ssize_t sret;
/* return any leftover data */
if (sret != -EBUSY)
return sret;
- trace_seq_reset(&iter->seq);
+ trace_seq_init(&iter->seq);
+ /* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
+ if (unlikely(old_tracer != current_trace && current_trace)) {
+ old_tracer = current_trace;
+ *iter->trace = *current_trace;
+ }
+ mutex_unlock(&trace_types_lock);
+
+ /*
+ * Avoid more than one consumer on a single file descriptor
+ * This is just a matter of traces coherency, the ring buffer itself
+ * is protected.
+ */
+ mutex_lock(&iter->mutex);
if (iter->trace->read) {
sret = iter->trace->read(iter, filp, ubuf, cnt, ppos);
if (sret)
/* Now copy what we have to the user */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
if (iter->seq.readpos >= iter->seq.len)
- trace_seq_reset(&iter->seq);
+ trace_seq_init(&iter->seq);
/*
* If there was nothing to send to user, inspite of consuming trace
goto waitagain;
out:
- mutex_unlock(&trace_types_lock);
+ mutex_unlock(&iter->mutex);
return sret;
}
};
static size_t
-tracing_fill_pipe_page(struct page *pages, size_t rem,
- struct trace_iterator *iter)
+tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter)
{
size_t count;
int ret;
.ops = &tracing_pipe_buf_ops,
.spd_release = tracing_spd_release_pipe,
};
+ static struct tracer *old_tracer;
ssize_t ret;
size_t rem;
unsigned int i;
+ /* copy the tracer to avoid using a global lock all around */
mutex_lock(&trace_types_lock);
+ if (unlikely(old_tracer != current_trace && current_trace)) {
+ old_tracer = current_trace;
+ *iter->trace = *current_trace;
+ }
+ mutex_unlock(&trace_types_lock);
+
+ mutex_lock(&iter->mutex);
if (iter->trace->splice_read) {
ret = iter->trace->splice_read(iter, filp,
if (!pages[i])
break;
- rem = tracing_fill_pipe_page(pages[i], rem, iter);
+ rem = tracing_fill_pipe_page(rem, iter);
/* Copy the data into the page, so we can start over. */
ret = trace_seq_to_buffer(&iter->seq,
partial[i].offset = 0;
partial[i].len = iter->seq.len;
- trace_seq_reset(&iter->seq);
+ trace_seq_init(&iter->seq);
}
- mutex_unlock(&trace_types_lock);
+ mutex_unlock(&iter->mutex);
spd.nr_pages = i;
return splice_to_pipe(pipe, &spd);
out_err:
- mutex_unlock(&trace_types_lock);
+ mutex_unlock(&iter->mutex);
return ret;
}
size_t cnt, loff_t *ppos)
{
struct trace_array *tr = filp->private_data;
- char buf[64];
+ char buf[96];
int r;
- r = sprintf(buf, "%lu\n", tr->entries >> 10);
+ mutex_lock(&trace_types_lock);
+ if (!ring_buffer_expanded)
+ r = sprintf(buf, "%lu (expanded: %lu)\n",
+ tr->entries >> 10,
+ trace_buf_size >> 10);
+ else
+ r = sprintf(buf, "%lu\n", tr->entries >> 10);
+ mutex_unlock(&trace_types_lock);
+
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
}
val <<= 10;
if (val != global_trace.entries) {
- ret = ring_buffer_resize(global_trace.buffer, val);
- if (ret < 0) {
- cnt = ret;
- goto out;
- }
-
- ret = ring_buffer_resize(max_tr.buffer, val);
+ ret = tracing_resize_ring_buffer(val);
if (ret < 0) {
- int r;
cnt = ret;
- r = ring_buffer_resize(global_trace.buffer,
- global_trace.entries);
- if (r < 0) {
- /* AARGH! We are left with different
- * size max buffer!!!! */
- WARN_ON(1);
- tracing_disabled = 1;
- }
goto out;
}
-
- global_trace.entries = val;
}
filp->f_pos += cnt;
int ret;
va_list args;
va_start(args, fmt);
- ret = trace_vprintk(0, -1, fmt, args);
+ ret = trace_vprintk(0, fmt, args);
va_end(args);
return ret;
}
return cnt;
}
-static struct file_operations tracing_max_lat_fops = {
+static const struct file_operations tracing_max_lat_fops = {
.open = tracing_open_generic,
.read = tracing_max_lat_read,
.write = tracing_max_lat_write,
};
-static struct file_operations tracing_ctrl_fops = {
+static const struct file_operations tracing_ctrl_fops = {
.open = tracing_open_generic,
.read = tracing_ctrl_read,
.write = tracing_ctrl_write,
};
-static struct file_operations set_tracer_fops = {
+static const struct file_operations set_tracer_fops = {
.open = tracing_open_generic,
.read = tracing_set_trace_read,
.write = tracing_set_trace_write,
};
-static struct file_operations tracing_pipe_fops = {
+static const struct file_operations tracing_pipe_fops = {
.open = tracing_open_pipe,
.poll = tracing_poll_pipe,
.read = tracing_read_pipe,
.release = tracing_release_pipe,
};
-static struct file_operations tracing_entries_fops = {
+static const struct file_operations tracing_entries_fops = {
.open = tracing_open_generic,
.read = tracing_entries_read,
.write = tracing_entries_write,
};
-static struct file_operations tracing_mark_fops = {
+static const struct file_operations tracing_mark_fops = {
.open = tracing_open_generic,
.write = tracing_mark_write,
};
-#ifdef CONFIG_DYNAMIC_FTRACE
+struct ftrace_buffer_info {
+ struct trace_array *tr;
+ void *spare;
+ int cpu;
+ unsigned int read;
+};
-int __weak ftrace_arch_read_dyn_info(char *buf, int size)
+static int tracing_buffers_open(struct inode *inode, struct file *filp)
{
+ int cpu = (int)(long)inode->i_private;
+ struct ftrace_buffer_info *info;
+
+ if (tracing_disabled)
+ return -ENODEV;
+
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+
+ info->tr = &global_trace;
+ info->cpu = cpu;
+ info->spare = ring_buffer_alloc_read_page(info->tr->buffer);
+ /* Force reading ring buffer for first read */
+ info->read = (unsigned int)-1;
+ if (!info->spare)
+ goto out;
+
+ filp->private_data = info;
+
return 0;
+
+ out:
+ kfree(info);
+ return -ENOMEM;
}
static ssize_t
-tracing_read_dyn_info(struct file *filp, char __user *ubuf,
- size_t cnt, loff_t *ppos)
+tracing_buffers_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *ppos)
{
- static char ftrace_dyn_info_buffer[1024];
- static DEFINE_MUTEX(dyn_info_mutex);
- unsigned long *p = filp->private_data;
- char *buf = ftrace_dyn_info_buffer;
- int size = ARRAY_SIZE(ftrace_dyn_info_buffer);
- int r;
+ struct ftrace_buffer_info *info = filp->private_data;
+ unsigned int pos;
+ ssize_t ret;
+ size_t size;
- mutex_lock(&dyn_info_mutex);
- r = sprintf(buf, "%ld ", *p);
+ if (!count)
+ return 0;
- r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r);
- buf[r++] = '\n';
+ /* Do we have previous read data to read? */
+ if (info->read < PAGE_SIZE)
+ goto read;
- r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+ info->read = 0;
- mutex_unlock(&dyn_info_mutex);
+ ret = ring_buffer_read_page(info->tr->buffer,
+ &info->spare,
+ count,
+ info->cpu, 0);
+ if (ret < 0)
+ return 0;
- return r;
-}
+ pos = ring_buffer_page_len(info->spare);
-static struct file_operations tracing_dyn_info_fops = {
- .open = tracing_open_generic,
- .read = tracing_read_dyn_info,
-};
-#endif
+ if (pos < PAGE_SIZE)
+ memset(info->spare + pos, 0, PAGE_SIZE - pos);
-static struct dentry *d_tracer;
+read:
+ size = PAGE_SIZE - info->read;
+ if (size > count)
+ size = count;
-struct dentry *tracing_init_dentry(void)
-{
- static int once;
+ ret = copy_to_user(ubuf, info->spare + info->read, size);
+ if (ret == size)
+ return -EFAULT;
+ size -= ret;
- if (d_tracer)
- return d_tracer;
+ *ppos += size;
+ info->read += size;
- d_tracer = debugfs_create_dir("tracing", NULL);
+ return size;
+}
- if (!d_tracer && !once) {
- once = 1;
- pr_warning("Could not create debugfs directory 'tracing'\n");
- return NULL;
- }
+static int tracing_buffers_release(struct inode *inode, struct file *file)
+{
+ struct ftrace_buffer_info *info = file->private_data;
- return d_tracer;
+ ring_buffer_free_read_page(info->tr->buffer, info->spare);
+ kfree(info);
+
+ return 0;
}
-#ifdef CONFIG_FTRACE_SELFTEST
-/* Let selftest have access to static functions in this file */
-#include "trace_selftest.c"
-#endif
+struct buffer_ref {
+ struct ring_buffer *buffer;
+ void *page;
+ int ref;
+};
-static __init int tracer_init_debugfs(void)
+static void buffer_pipe_buf_release(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
{
- struct dentry *d_tracer;
- struct dentry *entry;
+ struct buffer_ref *ref = (struct buffer_ref *)buf->private;
- d_tracer = tracing_init_dentry();
+ if (--ref->ref)
+ return;
- entry = debugfs_create_file("tracing_enabled", 0644, d_tracer,
- &global_trace, &tracing_ctrl_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
+ ring_buffer_free_read_page(ref->buffer, ref->page);
+ kfree(ref);
+ buf->private = 0;
+}
+
+static int buffer_pipe_buf_steal(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ return 1;
+}
+
+static void buffer_pipe_buf_get(struct pipe_inode_info *pipe,
+ struct pipe_buffer *buf)
+{
+ struct buffer_ref *ref = (struct buffer_ref *)buf->private;
+
+ ref->ref++;
+}
+
+/* Pipe buffer operations for a buffer. */
+static struct pipe_buf_operations buffer_pipe_buf_ops = {
+ .can_merge = 0,
+ .map = generic_pipe_buf_map,
+ .unmap = generic_pipe_buf_unmap,
+ .confirm = generic_pipe_buf_confirm,
+ .release = buffer_pipe_buf_release,
+ .steal = buffer_pipe_buf_steal,
+ .get = buffer_pipe_buf_get,
+};
+
+/*
+ * Callback from splice_to_pipe(), if we need to release some pages
+ * at the end of the spd in case we error'ed out in filling the pipe.
+ */
+static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i)
+{
+ struct buffer_ref *ref =
+ (struct buffer_ref *)spd->partial[i].private;
+
+ if (--ref->ref)
+ return;
+
+ ring_buffer_free_read_page(ref->buffer, ref->page);
+ kfree(ref);
+ spd->partial[i].private = 0;
+}
+
+static ssize_t
+tracing_buffers_splice_read(struct file *file, loff_t *ppos,
+ struct pipe_inode_info *pipe, size_t len,
+ unsigned int flags)
+{
+ struct ftrace_buffer_info *info = file->private_data;
+ struct partial_page partial[PIPE_BUFFERS];
+ struct page *pages[PIPE_BUFFERS];
+ struct splice_pipe_desc spd = {
+ .pages = pages,
+ .partial = partial,
+ .flags = flags,
+ .ops = &buffer_pipe_buf_ops,
+ .spd_release = buffer_spd_release,
+ };
+ struct buffer_ref *ref;
+ int size, i;
+ size_t ret;
+
+ /*
+ * We can't seek on a buffer input
+ */
+ if (unlikely(*ppos))
+ return -ESPIPE;
+
+
+ for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) {
+ struct page *page;
+ int r;
+
+ ref = kzalloc(sizeof(*ref), GFP_KERNEL);
+ if (!ref)
+ break;
+
+ ref->buffer = info->tr->buffer;
+ ref->page = ring_buffer_alloc_read_page(ref->buffer);
+ if (!ref->page) {
+ kfree(ref);
+ break;
+ }
+
+ r = ring_buffer_read_page(ref->buffer, &ref->page,
+ len, info->cpu, 0);
+ if (r < 0) {
+ ring_buffer_free_read_page(ref->buffer,
+ ref->page);
+ kfree(ref);
+ break;
+ }
+
+ /*
+ * zero out any left over data, this is going to
+ * user land.
+ */
+ size = ring_buffer_page_len(ref->page);
+ if (size < PAGE_SIZE)
+ memset(ref->page + size, 0, PAGE_SIZE - size);
+
+ page = virt_to_page(ref->page);
+
+ spd.pages[i] = page;
+ spd.partial[i].len = PAGE_SIZE;
+ spd.partial[i].offset = 0;
+ spd.partial[i].private = (unsigned long)ref;
+ spd.nr_pages++;
+ }
+
+ spd.nr_pages = i;
+
+ /* did we read anything? */
+ if (!spd.nr_pages) {
+ if (flags & SPLICE_F_NONBLOCK)
+ ret = -EAGAIN;
+ else
+ ret = 0;
+ /* TODO: block */
+ return ret;
+ }
+
+ ret = splice_to_pipe(pipe, &spd);
+
+ return ret;
+}
+
+static const struct file_operations tracing_buffers_fops = {
+ .open = tracing_buffers_open,
+ .read = tracing_buffers_read,
+ .release = tracing_buffers_release,
+ .splice_read = tracing_buffers_splice_read,
+ .llseek = no_llseek,
+};
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+
+int __weak ftrace_arch_read_dyn_info(char *buf, int size)
+{
+ return 0;
+}
+
+static ssize_t
+tracing_read_dyn_info(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ static char ftrace_dyn_info_buffer[1024];
+ static DEFINE_MUTEX(dyn_info_mutex);
+ unsigned long *p = filp->private_data;
+ char *buf = ftrace_dyn_info_buffer;
+ int size = ARRAY_SIZE(ftrace_dyn_info_buffer);
+ int r;
+
+ mutex_lock(&dyn_info_mutex);
+ r = sprintf(buf, "%ld ", *p);
+
+ r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r);
+ buf[r++] = '\n';
+
+ r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
+
+ mutex_unlock(&dyn_info_mutex);
+
+ return r;
+}
+
+static const struct file_operations tracing_dyn_info_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_read_dyn_info,
+};
+#endif
+
+static struct dentry *d_tracer;
+
+struct dentry *tracing_init_dentry(void)
+{
+ static int once;
+
+ if (d_tracer)
+ return d_tracer;
+
+ if (!debugfs_initialized())
+ return NULL;
+
+ d_tracer = debugfs_create_dir("tracing", NULL);
+
+ if (!d_tracer && !once) {
+ once = 1;
+ pr_warning("Could not create debugfs directory 'tracing'\n");
+ return NULL;
+ }
+
+ return d_tracer;
+}
+
+static struct dentry *d_percpu;
+
+struct dentry *tracing_dentry_percpu(void)
+{
+ static int once;
+ struct dentry *d_tracer;
+
+ if (d_percpu)
+ return d_percpu;
+
+ d_tracer = tracing_init_dentry();
+
+ if (!d_tracer)
+ return NULL;
+
+ d_percpu = debugfs_create_dir("per_cpu", d_tracer);
+
+ if (!d_percpu && !once) {
+ once = 1;
+ pr_warning("Could not create debugfs directory 'per_cpu'\n");
+ return NULL;
+ }
+
+ return d_percpu;
+}
+
+static void tracing_init_debugfs_percpu(long cpu)
+{
+ struct dentry *d_percpu = tracing_dentry_percpu();
+ struct dentry *entry, *d_cpu;
+ /* strlen(cpu) + MAX(log10(cpu)) + '\0' */
+ char cpu_dir[7];
+
+ if (cpu > 999 || cpu < 0)
+ return;
+
+ sprintf(cpu_dir, "cpu%ld", cpu);
+ d_cpu = debugfs_create_dir(cpu_dir, d_percpu);
+ if (!d_cpu) {
+ pr_warning("Could not create debugfs '%s' entry\n", cpu_dir);
+ return;
+ }
+
+ /* per cpu trace_pipe */
+ entry = debugfs_create_file("trace_pipe", 0444, d_cpu,
+ (void *) cpu, &tracing_pipe_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace_pipe' entry\n");
+
+ /* per cpu trace */
+ entry = debugfs_create_file("trace", 0644, d_cpu,
+ (void *) cpu, &tracing_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace' entry\n");
+
+ entry = debugfs_create_file("trace_pipe_raw", 0444, d_cpu,
+ (void *) cpu, &tracing_buffers_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'trace_pipe_raw' entry\n");
+}
+
+#ifdef CONFIG_FTRACE_SELFTEST
+/* Let selftest have access to static functions in this file */
+#include "trace_selftest.c"
+#endif
+
+struct trace_option_dentry {
+ struct tracer_opt *opt;
+ struct tracer_flags *flags;
+ struct dentry *entry;
+};
+
+static ssize_t
+trace_options_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_option_dentry *topt = filp->private_data;
+ char *buf;
+
+ if (topt->flags->val & topt->opt->bit)
+ buf = "1\n";
+ else
+ buf = "0\n";
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
+}
+
+static ssize_t
+trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ struct trace_option_dentry *topt = filp->private_data;
+ unsigned long val;
+ char buf[64];
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ ret = 0;
+ switch (val) {
+ case 0:
+ /* do nothing if already cleared */
+ if (!(topt->flags->val & topt->opt->bit))
+ break;
+
+ mutex_lock(&trace_types_lock);
+ if (current_trace->set_flag)
+ ret = current_trace->set_flag(topt->flags->val,
+ topt->opt->bit, 0);
+ mutex_unlock(&trace_types_lock);
+ if (ret)
+ return ret;
+ topt->flags->val &= ~topt->opt->bit;
+ break;
+ case 1:
+ /* do nothing if already set */
+ if (topt->flags->val & topt->opt->bit)
+ break;
+
+ mutex_lock(&trace_types_lock);
+ if (current_trace->set_flag)
+ ret = current_trace->set_flag(topt->flags->val,
+ topt->opt->bit, 1);
+ mutex_unlock(&trace_types_lock);
+ if (ret)
+ return ret;
+ topt->flags->val |= topt->opt->bit;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+
+static const struct file_operations trace_options_fops = {
+ .open = tracing_open_generic,
+ .read = trace_options_read,
+ .write = trace_options_write,
+};
+
+static ssize_t
+trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ long index = (long)filp->private_data;
+ char *buf;
+
+ if (trace_flags & (1 << index))
+ buf = "1\n";
+ else
+ buf = "0\n";
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2);
+}
+
+static ssize_t
+trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt,
+ loff_t *ppos)
+{
+ long index = (long)filp->private_data;
+ char buf[64];
+ unsigned long val;
+ int ret;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ ret = strict_strtoul(buf, 10, &val);
+ if (ret < 0)
+ return ret;
+
+ switch (val) {
+ case 0:
+ trace_flags &= ~(1 << index);
+ break;
+ case 1:
+ trace_flags |= 1 << index;
+ break;
+
+ default:
+ return -EINVAL;
+ }
+
+ *ppos += cnt;
+
+ return cnt;
+}
+
+static const struct file_operations trace_options_core_fops = {
+ .open = tracing_open_generic,
+ .read = trace_options_core_read,
+ .write = trace_options_core_write,
+};
+
+static struct dentry *trace_options_init_dentry(void)
+{
+ struct dentry *d_tracer;
+ static struct dentry *t_options;
+
+ if (t_options)
+ return t_options;
+
+ d_tracer = tracing_init_dentry();
+ if (!d_tracer)
+ return NULL;
+
+ t_options = debugfs_create_dir("options", d_tracer);
+ if (!t_options) {
+ pr_warning("Could not create debugfs directory 'options'\n");
+ return NULL;
+ }
+
+ return t_options;
+}
+
+static void
+create_trace_option_file(struct trace_option_dentry *topt,
+ struct tracer_flags *flags,
+ struct tracer_opt *opt)
+{
+ struct dentry *t_options;
+ struct dentry *entry;
+
+ t_options = trace_options_init_dentry();
+ if (!t_options)
+ return;
+
+ topt->flags = flags;
+ topt->opt = opt;
+
+ entry = debugfs_create_file(opt->name, 0644, t_options, topt,
+ &trace_options_fops);
+
+ topt->entry = entry;
+
+}
+
+static struct trace_option_dentry *
+create_trace_option_files(struct tracer *tracer)
+{
+ struct trace_option_dentry *topts;
+ struct tracer_flags *flags;
+ struct tracer_opt *opts;
+ int cnt;
+
+ if (!tracer)
+ return NULL;
+
+ flags = tracer->flags;
+
+ if (!flags || !flags->opts)
+ return NULL;
+
+ opts = flags->opts;
+
+ for (cnt = 0; opts[cnt].name; cnt++)
+ ;
+
+ topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL);
+ if (!topts)
+ return NULL;
+
+ for (cnt = 0; opts[cnt].name; cnt++)
+ create_trace_option_file(&topts[cnt], flags,
+ &opts[cnt]);
+
+ return topts;
+}
+
+static void
+destroy_trace_option_files(struct trace_option_dentry *topts)
+{
+ int cnt;
+
+ if (!topts)
+ return;
+
+ for (cnt = 0; topts[cnt].opt; cnt++) {
+ if (topts[cnt].entry)
+ debugfs_remove(topts[cnt].entry);
+ }
+
+ kfree(topts);
+}
+
+static struct dentry *
+create_trace_option_core_file(const char *option, long index)
+{
+ struct dentry *t_options;
+ struct dentry *entry;
+
+ t_options = trace_options_init_dentry();
+ if (!t_options)
+ return NULL;
+
+ entry = debugfs_create_file(option, 0644, t_options, (void *)index,
+ &trace_options_core_fops);
+
+ return entry;
+}
+
+static __init void create_trace_options_dir(void)
+{
+ struct dentry *t_options;
+ struct dentry *entry;
+ int i;
+
+ t_options = trace_options_init_dentry();
+ if (!t_options)
+ return;
+
+ for (i = 0; trace_options[i]; i++) {
+ entry = create_trace_option_core_file(trace_options[i], i);
+ if (!entry)
+ pr_warning("Could not create debugfs %s entry\n",
+ trace_options[i]);
+ }
+}
+
+static __init int tracer_init_debugfs(void)
+{
+ struct dentry *d_tracer;
+ struct dentry *entry;
+ int cpu;
+
+ d_tracer = tracing_init_dentry();
+
+ entry = debugfs_create_file("tracing_enabled", 0644, d_tracer,
+ &global_trace, &tracing_ctrl_fops);
+ if (!entry)
+ pr_warning("Could not create debugfs 'tracing_enabled' entry\n");
entry = debugfs_create_file("trace_options", 0644, d_tracer,
NULL, &tracing_iter_fops);
if (!entry)
pr_warning("Could not create debugfs 'trace_options' entry\n");
+ create_trace_options_dir();
+
entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer,
NULL, &tracing_cpumask_fops);
if (!entry)
pr_warning("Could not create debugfs 'tracing_cpumask' entry\n");
- entry = debugfs_create_file("latency_trace", 0444, d_tracer,
- &global_trace, &tracing_lt_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'latency_trace' entry\n");
-
- entry = debugfs_create_file("trace", 0444, d_tracer,
- &global_trace, &tracing_fops);
+ entry = debugfs_create_file("trace", 0644, d_tracer,
+ (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
if (!entry)
pr_warning("Could not create debugfs 'trace' entry\n");
if (!entry)
pr_warning("Could not create debugfs 'README' entry\n");
- entry = debugfs_create_file("trace_pipe", 0644, d_tracer,
- NULL, &tracing_pipe_fops);
+ entry = debugfs_create_file("trace_pipe", 0444, d_tracer,
+ (void *) TRACE_PIPE_ALL_CPU, &tracing_pipe_fops);
if (!entry)
pr_warning("Could not create debugfs "
"'trace_pipe' entry\n");
#ifdef CONFIG_SYSPROF_TRACER
init_tracer_sysprof_debugfs(d_tracer);
#endif
- return 0;
-}
-int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
-{
- static DEFINE_SPINLOCK(trace_buf_lock);
- static char trace_buf[TRACE_BUF_SIZE];
-
- struct ring_buffer_event *event;
- struct trace_array *tr = &global_trace;
- struct trace_array_cpu *data;
- int cpu, len = 0, size, pc;
- struct print_entry *entry;
- unsigned long irq_flags;
-
- if (tracing_disabled || tracing_selftest_running)
- return 0;
-
- pc = preempt_count();
- preempt_disable_notrace();
- cpu = raw_smp_processor_id();
- data = tr->data[cpu];
-
- if (unlikely(atomic_read(&data->disabled)))
- goto out;
-
- pause_graph_tracing();
- spin_lock_irqsave(&trace_buf_lock, irq_flags);
- len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, args);
-
- len = min(len, TRACE_BUF_SIZE-1);
- trace_buf[len] = 0;
+ for_each_tracing_cpu(cpu)
+ tracing_init_debugfs_percpu(cpu);
- size = sizeof(*entry) + len + 1;
- event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
- if (!event)
- goto out_unlock;
- entry = ring_buffer_event_data(event);
- entry->ip = ip;
- entry->depth = depth;
-
- memcpy(&entry->buf, trace_buf, len);
- entry->buf[len] = 0;
- ring_buffer_unlock_commit(tr->buffer, event);
-
- out_unlock:
- spin_unlock_irqrestore(&trace_buf_lock, irq_flags);
- unpause_graph_tracing();
- out:
- preempt_enable_notrace();
-
- return len;
-}
-EXPORT_SYMBOL_GPL(trace_vprintk);
-
-int __ftrace_printk(unsigned long ip, const char *fmt, ...)
-{
- int ret;
- va_list ap;
-
- if (!(trace_flags & TRACE_ITER_PRINTK))
- return 0;
-
- va_start(ap, fmt);
- ret = trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
- va_end(ap);
- return ret;
-}
-EXPORT_SYMBOL_GPL(__ftrace_printk);
-
-int __ftrace_vprintk(unsigned long ip, const char *fmt, va_list ap)
-{
- if (!(trace_flags & TRACE_ITER_PRINTK))
- return 0;
-
- return trace_vprintk(ip, task_curr_ret_stack(current), fmt, ap);
+ return 0;
}
-EXPORT_SYMBOL_GPL(__ftrace_vprintk);
static int trace_panic_handler(struct notifier_block *this,
unsigned long event, void *unused)
printk(KERN_TRACE "%s", s->buffer);
- trace_seq_reset(s);
+ trace_seq_init(s);
}
-void ftrace_dump(void)
+static void __ftrace_dump(bool disable_tracing)
{
static DEFINE_SPINLOCK(ftrace_dump_lock);
/* use static because iter can be a bit big for the stack */
static struct trace_iterator iter;
+ unsigned int old_userobj;
static int dump_ran;
unsigned long flags;
int cnt = 0, cpu;
dump_ran = 1;
- /* No turning back! */
tracing_off();
- ftrace_kill();
+
+ if (disable_tracing)
+ ftrace_kill();
for_each_tracing_cpu(cpu) {
atomic_inc(&global_trace.data[cpu]->disabled);
}
+ old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
+
/* don't look at user memory in panic mode */
trace_flags &= ~TRACE_ITER_SYM_USEROBJ;
printk(KERN_TRACE "Dumping ftrace buffer:\n");
+ /* Simulate the iterator */
iter.tr = &global_trace;
iter.trace = current_trace;
+ iter.cpu_file = TRACE_PIPE_ALL_CPU;
/*
* We need to stop all tracing on all CPUS to read the
else
printk(KERN_TRACE "---------------------------------\n");
+ /* Re-enable tracing if requested */
+ if (!disable_tracing) {
+ trace_flags |= old_userobj;
+
+ for_each_tracing_cpu(cpu) {
+ atomic_dec(&global_trace.data[cpu]->disabled);
+ }
+ tracing_on();
+ }
+
out:
spin_unlock_irqrestore(&ftrace_dump_lock, flags);
}
+/* By default: disable tracing after the dump */
+void ftrace_dump(void)
+{
+ __ftrace_dump(true);
+}
+
__init static int tracer_alloc_buffers(void)
{
struct trace_array_cpu *data;
+ int ring_buf_size;
int i;
int ret = -ENOMEM;
if (!alloc_cpumask_var(&tracing_cpumask, GFP_KERNEL))
goto out_free_buffer_mask;
+ if (!alloc_cpumask_var(&tracing_reader_cpumask, GFP_KERNEL))
+ goto out_free_tracing_cpumask;
+
+ /* To save memory, keep the ring buffer size to its minimum */
+ if (ring_buffer_expanded)
+ ring_buf_size = trace_buf_size;
+ else
+ ring_buf_size = 1;
+
cpumask_copy(tracing_buffer_mask, cpu_possible_mask);
cpumask_copy(tracing_cpumask, cpu_all_mask);
+ cpumask_clear(tracing_reader_cpumask);
/* TODO: make the number of buffers hot pluggable with CPUS */
- global_trace.buffer = ring_buffer_alloc(trace_buf_size,
+ global_trace.buffer = ring_buffer_alloc(ring_buf_size,
TRACE_BUFFER_FLAGS);
if (!global_trace.buffer) {
printk(KERN_ERR "tracer: failed to allocate ring buffer!\n");
#ifdef CONFIG_TRACER_MAX_TRACE
- max_tr.buffer = ring_buffer_alloc(trace_buf_size,
+ max_tr.buffer = ring_buffer_alloc(ring_buf_size,
TRACE_BUFFER_FLAGS);
if (!max_tr.buffer) {
printk(KERN_ERR "tracer: failed to allocate max ring buffer!\n");
&trace_panic_notifier);
register_die_notifier(&trace_die_notifier);
- ret = 0;
+
+ return 0;
out_free_cpumask:
+ free_cpumask_var(tracing_reader_cpumask);
+out_free_tracing_cpumask:
free_cpumask_var(tracing_cpumask);
out_free_buffer_mask:
free_cpumask_var(tracing_buffer_mask);