#include <linux/writeback.h>
#include <linux/kallsyms.h>
#include <linux/seq_file.h>
+#include <linux/smp_lock.h>
#include <linux/notifier.h>
#include <linux/irqflags.h>
#include <linux/debugfs.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>
#define TRACE_BUFFER_FLAGS (RB_FL_OVERWRITE)
-unsigned long __read_mostly tracing_max_latency;
-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;
+int ring_buffer_expanded;
/*
* We need to change this state when a selftest is running.
/*
* If a tracer is running, we do not want to run SELFTEST.
*/
-static bool __read_mostly tracing_selftest_disabled;
+bool __read_mostly tracing_selftest_disabled;
/* For tracers that don't implement custom flags */
static struct tracer_opt dummy_tracer_opt[] = {
*/
static int tracing_disabled = 1;
-static DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
+DEFINE_PER_CPU(local_t, ftrace_cpu_disabled);
static inline void ftrace_disable_cpu(void)
{
}
__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);
+int filter_current_check_discard(struct ring_buffer *buffer,
+ struct ftrace_event_call *call, void *rec,
+ struct ring_buffer_event *event)
+{
+ return filter_check_discard(call, rec, buffer, event);
+}
+EXPORT_SYMBOL_GPL(filter_current_check_discard);
+
+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_ITER_GRAPH_TIME;
+
+static int trace_stop_count;
+static DEFINE_SPINLOCK(tracing_start_lock);
/**
* trace_wake_up - wake up tasks waiting for trace input
static int __init set_buf_size(char *str)
{
unsigned long buf_size;
- int ret;
if (!str)
return 0;
- ret = strict_strtoul(str, 0, &buf_size);
+ buf_size = memparse(str, &str);
/* nr_entries can not be zero */
- if (ret < 0 || buf_size == 0)
+ if (buf_size == 0)
return 0;
trace_buf_size = buf_size;
return 1;
"printk-msg-only",
"context-info",
"latency-format",
+ "sleep-time",
+ "graph-time",
NULL
};
+static struct {
+ u64 (*func)(void);
+ const char *name;
+} trace_clocks[] = {
+ { trace_clock_local, "local" },
+ { trace_clock_global, "global" },
+};
+
+int trace_clock_id;
+
/*
- * ftrace_max_lock is used to protect the swapping of buffers
- * when taking a max snapshot. The buffers themselves are
- * protected by per_cpu spinlocks. But the action of the swap
- * needs its own lock.
- *
- * This is defined as a raw_spinlock_t in order to help
- * with performance when lockdep debugging is enabled.
+ * trace_parser_get_init - gets the buffer for trace parser
*/
-static raw_spinlock_t ftrace_max_lock =
- (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+int trace_parser_get_init(struct trace_parser *parser, int size)
+{
+ memset(parser, 0, sizeof(*parser));
+
+ parser->buffer = kmalloc(size, GFP_KERNEL);
+ if (!parser->buffer)
+ return 1;
+
+ parser->size = size;
+ return 0;
+}
/*
- * Copy the new maximum trace into the separate maximum-trace
- * structure. (this way the maximum trace is permanently saved,
- * for later retrieval via /debugfs/tracing/latency_trace)
+ * trace_parser_put - frees the buffer for trace parser
*/
-static void
-__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
+void trace_parser_put(struct trace_parser *parser)
{
- struct trace_array_cpu *data = tr->data[cpu];
+ kfree(parser->buffer);
+}
- max_tr.cpu = cpu;
- max_tr.time_start = data->preempt_timestamp;
+/*
+ * trace_get_user - reads the user input string separated by space
+ * (matched by isspace(ch))
+ *
+ * For each string found the 'struct trace_parser' is updated,
+ * and the function returns.
+ *
+ * Returns number of bytes read.
+ *
+ * See kernel/trace/trace.h for 'struct trace_parser' details.
+ */
+int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char ch;
+ size_t read = 0;
+ ssize_t ret;
- data = max_tr.data[cpu];
- data->saved_latency = tracing_max_latency;
+ if (!*ppos)
+ trace_parser_clear(parser);
- memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
- data->pid = tsk->pid;
- data->uid = task_uid(tsk);
- data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
- data->policy = tsk->policy;
- data->rt_priority = tsk->rt_priority;
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
- /* record this tasks comm */
- tracing_record_cmdline(tsk);
+ read++;
+ cnt--;
+
+ /*
+ * The parser is not finished with the last write,
+ * continue reading the user input without skipping spaces.
+ */
+ if (!parser->cont) {
+ /* skip white space */
+ while (cnt && isspace(ch)) {
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* only spaces were written */
+ if (isspace(ch)) {
+ *ppos += read;
+ ret = read;
+ goto out;
+ }
+
+ parser->idx = 0;
+ }
+
+ /* read the non-space input */
+ while (cnt && !isspace(ch)) {
+ if (parser->idx < parser->size)
+ parser->buffer[parser->idx++] = ch;
+ else {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = get_user(ch, ubuf++);
+ if (ret)
+ goto out;
+ read++;
+ cnt--;
+ }
+
+ /* We either got finished input or we have to wait for another call. */
+ if (isspace(ch)) {
+ parser->buffer[parser->idx] = 0;
+ parser->cont = false;
+ } else {
+ parser->cont = true;
+ parser->buffer[parser->idx++] = ch;
+ }
+
+ *ppos += read;
+ ret = read;
+
+out:
+ return ret;
}
ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t 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;
return cnt;
}
+/*
+ * ftrace_max_lock is used to protect the swapping of buffers
+ * when taking a max snapshot. The buffers themselves are
+ * protected by per_cpu spinlocks. But the action of the swap
+ * needs its own lock.
+ *
+ * This is defined as a raw_spinlock_t in order to help
+ * with performance when lockdep debugging is enabled.
+ *
+ * It is also used in other places outside the update_max_tr
+ * so it needs to be defined outside of the
+ * CONFIG_TRACER_MAX_TRACE.
+ */
+static raw_spinlock_t ftrace_max_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
+
+#ifdef CONFIG_TRACER_MAX_TRACE
+unsigned long __read_mostly tracing_max_latency;
+unsigned long __read_mostly tracing_thresh;
+
+/*
+ * Copy the new maximum trace into the separate maximum-trace
+ * structure. (this way the maximum trace is permanently saved,
+ * for later retrieval via /sys/kernel/debug/tracing/latency_trace)
+ */
static void
-trace_print_seq(struct seq_file *m, struct trace_seq *s)
+__update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu)
{
- int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
+ struct trace_array_cpu *data = tr->data[cpu];
+ struct trace_array_cpu *max_data = tr->data[cpu];
- s->buffer[len] = 0;
- seq_puts(m, s->buffer);
+ max_tr.cpu = cpu;
+ max_tr.time_start = data->preempt_timestamp;
- trace_seq_init(s);
+ max_data = max_tr.data[cpu];
+ max_data->saved_latency = tracing_max_latency;
+ max_data->critical_start = data->critical_start;
+ max_data->critical_end = data->critical_end;
+
+ memcpy(data->comm, tsk->comm, TASK_COMM_LEN);
+ max_data->pid = tsk->pid;
+ max_data->uid = task_uid(tsk);
+ max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO;
+ max_data->policy = tsk->policy;
+ max_data->rt_priority = tsk->rt_priority;
+
+ /* record this tasks comm */
+ tracing_record_cmdline(tsk);
}
/**
{
struct ring_buffer *buf = tr->buffer;
+ if (trace_stop_count)
+ return;
+
WARN_ON_ONCE(!irqs_disabled());
__raw_spin_lock(&ftrace_max_lock);
tr->buffer = max_tr.buffer;
max_tr.buffer = buf;
- ftrace_disable_cpu();
- ring_buffer_reset(tr->buffer);
- ftrace_enable_cpu();
-
__update_max_tr(tr, tsk, cpu);
__raw_spin_unlock(&ftrace_max_lock);
}
{
int ret;
+ if (trace_stop_count)
+ return;
+
WARN_ON_ONCE(!irqs_disabled());
__raw_spin_lock(&ftrace_max_lock);
ftrace_disable_cpu();
- ring_buffer_reset(max_tr.buffer);
ret = ring_buffer_swap_cpu(max_tr.buffer, tr->buffer, cpu);
+ if (ret == -EBUSY) {
+ /*
+ * We failed to swap the buffer due to a commit taking
+ * place on this CPU. We fail to record, but we reset
+ * the max trace buffer (no one writes directly to it)
+ * and flag that it failed.
+ */
+ trace_array_printk(&max_tr, _THIS_IP_,
+ "Failed to swap buffers due to commit in progress\n");
+ }
+
ftrace_enable_cpu();
- WARN_ON_ONCE(ret && ret != -EAGAIN);
+ WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY);
__update_max_tr(tr, tsk, cpu);
__raw_spin_unlock(&ftrace_max_lock);
}
+#endif /* CONFIG_TRACER_MAX_TRACE */
/**
* register_tracer - register a tracer with the ftrace system.
if (type->selftest && !tracing_selftest_disabled) {
struct tracer *saved_tracer = current_trace;
struct trace_array *tr = &global_trace;
- int i;
/*
* Run a selftest on this tracer.
* internal tracing to verify that everything is in order.
* If we fail, we do not register this tracer.
*/
- for_each_tracing_cpu(i)
- tracing_reset(tr, i);
+ tracing_reset_online_cpus(tr);
current_trace = type;
/* the test is responsible for initializing and enabling */
goto out;
}
/* Only reset on passing, to avoid touching corrupted buffers */
- for_each_tracing_cpu(i)
- tracing_reset(tr, i);
+ tracing_reset_online_cpus(tr);
printk(KERN_CONT "PASSED\n");
}
mutex_unlock(&trace_types_lock);
}
-void tracing_reset(struct trace_array *tr, int cpu)
+static void __tracing_reset(struct trace_array *tr, int cpu)
{
ftrace_disable_cpu();
ring_buffer_reset_cpu(tr->buffer, cpu);
ftrace_enable_cpu();
}
+void tracing_reset(struct trace_array *tr, int cpu)
+{
+ struct ring_buffer *buffer = tr->buffer;
+
+ ring_buffer_record_disable(buffer);
+
+ /* Make sure all commits have finished */
+ synchronize_sched();
+ __tracing_reset(tr, cpu);
+
+ ring_buffer_record_enable(buffer);
+}
+
void tracing_reset_online_cpus(struct trace_array *tr)
{
+ struct ring_buffer *buffer = tr->buffer;
int cpu;
+ ring_buffer_record_disable(buffer);
+
+ /* Make sure all commits have finished */
+ synchronize_sched();
+
tr->time_start = ftrace_now(tr->cpu);
for_each_online_cpu(cpu)
- tracing_reset(tr, cpu);
+ __tracing_reset(tr, cpu);
+
+ ring_buffer_record_enable(buffer);
+}
+
+void tracing_reset_current(int cpu)
+{
+ tracing_reset(&global_trace, cpu);
+}
+
+void tracing_reset_current_online_cpus(void)
+{
+ tracing_reset_online_cpus(&global_trace);
}
#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 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 int trace_stop_count;
-static DEFINE_SPINLOCK(tracing_start_lock);
+int is_tracing_stopped(void)
+{
+ return trace_stop_count;
+}
/**
* ftrace_off_permanent - disable all ftrace code permanently
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;
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;
return;
}
+ preempt_disable();
__raw_spin_lock(&trace_cmdline_lock);
map = map_pid_to_cmdline[pid];
- if (map >= SAVED_CMDLINES)
- goto out;
-
- strcpy(comm, saved_cmdlines[map]);
+ if (map != NO_CMDLINE_MAP)
+ strcpy(comm, saved_cmdlines[map]);
+ else
+ strcpy(comm, "<...>");
- out:
__raw_spin_unlock(&trace_cmdline_lock);
+ preempt_enable();
}
void tracing_record_cmdline(struct task_struct *tsk)
{
- if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on())
+ 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->lock_depth = (tsk) ? tsk->lock_depth : 0;
entry->flags =
#ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT
(irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) |
((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) |
(need_resched() ? TRACE_FLAG_NEED_RESCHED : 0);
}
+EXPORT_SYMBOL_GPL(tracing_generic_entry_update);
-struct ring_buffer_event *trace_buffer_lock_reserve(struct trace_array *tr,
- unsigned char type,
- unsigned long len,
- unsigned long flags, int pc)
+struct ring_buffer_event *
+trace_buffer_lock_reserve(struct ring_buffer *buffer,
+ int type,
+ unsigned long len,
+ unsigned long flags, int pc)
{
struct ring_buffer_event *event;
- event = ring_buffer_lock_reserve(tr->buffer, len);
+ event = ring_buffer_lock_reserve(buffer, len);
if (event != NULL) {
struct trace_entry *ent = ring_buffer_event_data(event);
return event;
}
-static void ftrace_trace_stack(struct trace_array *tr,
- unsigned long flags, int skip, int pc);
-static void ftrace_trace_userstack(struct trace_array *tr,
- unsigned long flags, int pc);
-void trace_buffer_unlock_commit(struct trace_array *tr,
+static inline void
+__trace_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc,
+ int wake)
+{
+ ring_buffer_unlock_commit(buffer, event);
+
+ ftrace_trace_stack(buffer, flags, 6, pc);
+ ftrace_trace_userstack(buffer, flags, pc);
+
+ if (wake)
+ trace_wake_up();
+}
+
+void trace_buffer_unlock_commit(struct ring_buffer *buffer,
struct ring_buffer_event *event,
unsigned long flags, int pc)
{
- ring_buffer_unlock_commit(tr->buffer, event);
-
- ftrace_trace_stack(tr, flags, 6, pc);
- ftrace_trace_userstack(tr, flags, pc);
- trace_wake_up();
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
}
struct ring_buffer_event *
-trace_current_buffer_lock_reserve(unsigned char type, unsigned long len,
+trace_current_buffer_lock_reserve(struct ring_buffer **current_rb,
+ int type, unsigned long len,
unsigned long flags, int pc)
{
- return trace_buffer_lock_reserve(&global_trace,
+ *current_rb = global_trace.buffer;
+ return trace_buffer_lock_reserve(*current_rb,
type, len, flags, pc);
}
+EXPORT_SYMBOL_GPL(trace_current_buffer_lock_reserve);
-void trace_current_buffer_unlock_commit(struct ring_buffer_event *event,
+void trace_current_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
unsigned long flags, int pc)
{
- return trace_buffer_unlock_commit(&global_trace, event, flags, pc);
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 1);
+}
+EXPORT_SYMBOL_GPL(trace_current_buffer_unlock_commit);
+
+void trace_nowake_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event,
+ unsigned long flags, int pc)
+{
+ __trace_buffer_unlock_commit(buffer, event, flags, pc, 0);
}
+EXPORT_SYMBOL_GPL(trace_nowake_buffer_unlock_commit);
+
+void trace_current_buffer_discard_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event)
+{
+ ring_buffer_discard_commit(buffer, event);
+}
+EXPORT_SYMBOL_GPL(trace_current_buffer_discard_commit);
void
trace_function(struct trace_array *tr,
unsigned long ip, unsigned long parent_ip, unsigned long flags,
int pc)
{
+ struct ftrace_event_call *call = &event_function;
+ struct ring_buffer *buffer = tr->buffer;
struct ring_buffer_event *event;
struct ftrace_entry *entry;
if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
return;
- event = trace_buffer_lock_reserve(tr, TRACE_FN, sizeof(*entry),
+ event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry),
flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
entry->ip = ip;
entry->parent_ip = parent_ip;
- ring_buffer_unlock_commit(tr->buffer, event);
-}
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static void __trace_graph_entry(struct trace_array *tr,
- struct ftrace_graph_ent *trace,
- unsigned long flags,
- int pc)
-{
- struct ring_buffer_event *event;
- struct ftrace_graph_ent_entry *entry;
-
- if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
- return;
-
- event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->graph_ent = *trace;
- ring_buffer_unlock_commit(global_trace.buffer, event);
-}
-
-static void __trace_graph_return(struct trace_array *tr,
- struct ftrace_graph_ret *trace,
- unsigned long flags,
- int pc)
-{
- struct ring_buffer_event *event;
- struct ftrace_graph_ret_entry *entry;
-
- if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
- return;
-
- event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->ret = *trace;
- ring_buffer_unlock_commit(global_trace.buffer, event);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
-#endif
void
ftrace(struct trace_array *tr, struct trace_array_cpu *data,
trace_function(tr, ip, parent_ip, flags, pc);
}
-static void __ftrace_trace_stack(struct trace_array *tr,
+#ifdef CONFIG_STACKTRACE
+static void __ftrace_trace_stack(struct ring_buffer *buffer,
unsigned long flags,
int skip, int pc)
{
-#ifdef CONFIG_STACKTRACE
+ struct ftrace_event_call *call = &event_kernel_stack;
struct ring_buffer_event *event;
struct stack_entry *entry;
struct stack_trace trace;
- event = trace_buffer_lock_reserve(tr, TRACE_STACK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_STACK,
sizeof(*entry), flags, pc);
if (!event)
return;
trace.entries = entry->caller;
save_stack_trace(&trace);
- ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
-static void ftrace_trace_stack(struct trace_array *tr,
- unsigned long flags,
- int skip, int pc)
+void ftrace_trace_stack(struct ring_buffer *buffer, unsigned long flags,
+ int skip, int pc)
{
if (!(trace_flags & TRACE_ITER_STACKTRACE))
return;
- __ftrace_trace_stack(tr, flags, skip, pc);
+ __ftrace_trace_stack(buffer, flags, skip, pc);
}
-void __trace_stack(struct trace_array *tr,
- unsigned long flags,
- int skip, int pc)
+void __trace_stack(struct trace_array *tr, unsigned long flags, int skip,
+ int pc)
{
- __ftrace_trace_stack(tr, flags, skip, pc);
+ __ftrace_trace_stack(tr->buffer, flags, skip, pc);
}
-static void ftrace_trace_userstack(struct trace_array *tr,
- unsigned long flags, int pc)
+void
+ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc)
{
-#ifdef CONFIG_STACKTRACE
+ struct ftrace_event_call *call = &event_user_stack;
struct ring_buffer_event *event;
struct userstack_entry *entry;
struct stack_trace trace;
if (!(trace_flags & TRACE_ITER_USERSTACKTRACE))
return;
- event = trace_buffer_lock_reserve(tr, TRACE_USER_STACK,
+ event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK,
sizeof(*entry), flags, pc);
if (!event)
return;
entry = ring_buffer_event_data(event);
+ entry->tgid = current->tgid;
memset(&entry->caller, 0, sizeof(entry->caller));
trace.nr_entries = 0;
trace.entries = entry->caller;
save_stack_trace_user(&trace);
- ring_buffer_unlock_commit(tr->buffer, event);
-#endif
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
}
#ifdef UNUSED
}
#endif /* UNUSED */
+#endif /* CONFIG_STACKTRACE */
+
static void
ftrace_trace_special(void *__tr,
unsigned long arg1, unsigned long arg2, unsigned long arg3,
{
struct ring_buffer_event *event;
struct trace_array *tr = __tr;
+ struct ring_buffer *buffer = tr->buffer;
struct special_entry *entry;
- event = trace_buffer_lock_reserve(tr, TRACE_SPECIAL,
+ event = trace_buffer_lock_reserve(buffer, TRACE_SPECIAL,
sizeof(*entry), 0, pc);
if (!event)
return;
entry->arg1 = arg1;
entry->arg2 = arg2;
entry->arg3 = arg3;
- trace_buffer_unlock_commit(tr, event, 0, pc);
+ trace_buffer_unlock_commit(buffer, event, 0, pc);
}
void
}
void
-tracing_sched_switch_trace(struct trace_array *tr,
- struct task_struct *prev,
- struct task_struct *next,
- unsigned long flags, int pc)
-{
- struct ring_buffer_event *event;
- struct ctx_switch_entry *entry;
-
- event = trace_buffer_lock_reserve(tr, TRACE_CTX,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->prev_pid = prev->pid;
- entry->prev_prio = prev->prio;
- entry->prev_state = prev->state;
- entry->next_pid = next->pid;
- entry->next_prio = next->prio;
- entry->next_state = next->state;
- entry->next_cpu = task_cpu(next);
- trace_buffer_unlock_commit(tr, event, flags, pc);
-}
-
-void
-tracing_sched_wakeup_trace(struct trace_array *tr,
- struct task_struct *wakee,
- struct task_struct *curr,
- unsigned long flags, int pc)
-{
- struct ring_buffer_event *event;
- struct ctx_switch_entry *entry;
-
- event = trace_buffer_lock_reserve(tr, TRACE_WAKE,
- sizeof(*entry), flags, pc);
- if (!event)
- return;
- entry = ring_buffer_event_data(event);
- entry->prev_pid = curr->pid;
- entry->prev_prio = curr->prio;
- entry->prev_state = curr->state;
- entry->next_pid = wakee->pid;
- entry->next_prio = wakee->prio;
- entry->next_state = wakee->state;
- entry->next_cpu = task_cpu(wakee);
-
- ring_buffer_unlock_commit(tr->buffer, event);
- ftrace_trace_stack(tr, flags, 6, pc);
- ftrace_trace_userstack(tr, flags, pc);
-}
-
-void
ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
{
struct trace_array *tr = &global_trace;
local_irq_restore(flags);
}
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-int trace_graph_entry(struct ftrace_graph_ent *trace)
-{
- struct trace_array *tr = &global_trace;
- struct trace_array_cpu *data;
- unsigned long flags;
- long disabled;
- int cpu;
- int pc;
-
- if (!ftrace_trace_task(current))
- return 0;
-
- if (!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();
- __trace_graph_entry(tr, trace, flags, pc);
- }
- /* 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;
-}
-
-void trace_graph_return(struct ftrace_graph_ret *trace)
-{
- struct trace_array *tr = &global_trace;
- 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);
- }
- if (!trace->depth)
- clear_tsk_trace_graph(current);
- atomic_dec(&data->disabled);
- local_irq_restore(flags);
-}
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-
/**
* trace_vbprintk - write binary msg to tracing buffer
*
*/
-int trace_vbprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+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 ftrace_event_call *call = &event_bprint;
struct ring_buffer_event *event;
+ struct ring_buffer *buffer;
struct trace_array *tr = &global_trace;
struct trace_array_cpu *data;
struct bprint_entry *entry;
unsigned long flags;
+ int disable;
int resched;
int cpu, len = 0, size, pc;
cpu = raw_smp_processor_id();
data = tr->data[cpu];
- if (unlikely(atomic_read(&data->disabled)))
+ disable = atomic_inc_return(&data->disabled);
+ if (unlikely(disable != 1))
goto out;
/* Lockdep uses trace_printk for lock tracing */
goto out_unlock;
size = sizeof(*entry) + sizeof(u32) * len;
- event = trace_buffer_lock_reserve(tr, TRACE_BPRINT, size, flags, pc);
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size,
+ flags, pc);
if (!event)
goto out_unlock;
entry = ring_buffer_event_data(event);
entry->ip = ip;
- entry->depth = depth;
entry->fmt = fmt;
memcpy(entry->buf, trace_buf, sizeof(u32) * len);
- ring_buffer_unlock_commit(tr->buffer, event);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
out_unlock:
__raw_spin_unlock(&trace_buf_lock);
local_irq_restore(flags);
out:
+ atomic_dec_return(&data->disabled);
ftrace_preempt_enable(resched);
unpause_graph_tracing();
}
EXPORT_SYMBOL_GPL(trace_vbprintk);
-int trace_vprintk(unsigned long ip, int depth, const char *fmt, va_list args)
+int trace_array_printk(struct trace_array *tr,
+ 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_array_vprintk(tr, ip, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
+int trace_array_vprintk(struct trace_array *tr,
+ 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 ftrace_event_call *call = &event_print;
struct ring_buffer_event *event;
- struct trace_array *tr = &global_trace;
+ struct ring_buffer *buffer;
struct trace_array_cpu *data;
int cpu, len = 0, size, pc;
struct print_entry *entry;
unsigned long irq_flags;
+ int disable;
if (tracing_disabled || tracing_selftest_running)
return 0;
cpu = raw_smp_processor_id();
data = tr->data[cpu];
- if (unlikely(atomic_read(&data->disabled)))
+ disable = atomic_inc_return(&data->disabled);
+ if (unlikely(disable != 1))
goto out;
pause_graph_tracing();
trace_buf[len] = 0;
size = sizeof(*entry) + len + 1;
- event = trace_buffer_lock_reserve(tr, TRACE_PRINT, size, irq_flags, pc);
+ buffer = tr->buffer;
+ event = trace_buffer_lock_reserve(buffer, 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);
+ if (!filter_check_discard(call, entry, buffer, event))
+ ring_buffer_unlock_commit(buffer, event);
out_unlock:
__raw_spin_unlock(&trace_buf_lock);
raw_local_irq_restore(irq_flags);
unpause_graph_tracing();
out:
+ atomic_dec_return(&data->disabled);
preempt_enable_notrace();
return len;
}
+
+int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
+{
+ return trace_array_printk(&global_trace, ip, fmt, args);
+}
EXPORT_SYMBOL_GPL(trace_vprintk);
enum trace_file_type {
return ent;
}
+static void tracing_iter_reset(struct trace_iterator *iter, int cpu)
+{
+ struct trace_array *tr = iter->tr;
+ struct ring_buffer_event *event;
+ struct ring_buffer_iter *buf_iter;
+ unsigned long entries = 0;
+ u64 ts;
+
+ tr->data[cpu]->skipped_entries = 0;
+
+ if (!iter->buffer_iter[cpu])
+ return;
+
+ buf_iter = iter->buffer_iter[cpu];
+ ring_buffer_iter_reset(buf_iter);
+
+ /*
+ * We could have the case with the max latency tracers
+ * that a reset never took place on a cpu. This is evident
+ * by the timestamp being before the start of the buffer.
+ */
+ while ((event = ring_buffer_iter_peek(buf_iter, &ts))) {
+ if (ts >= iter->tr->time_start)
+ break;
+ entries++;
+ ring_buffer_read(buf_iter, NULL);
+ }
+
+ tr->data[cpu]->skipped_entries = entries;
+}
+
/*
* No necessary locking here. The worst thing which can
* happen is loosing events consumed at the same time
if (cpu_file == TRACE_PIPE_ALL_CPU) {
for_each_tracing_cpu(cpu)
- ring_buffer_iter_reset(iter->buffer_iter[cpu]);
+ tracing_iter_reset(iter, cpu);
} else
- ring_buffer_iter_reset(iter->buffer_iter[cpu_file]);
-
+ tracing_iter_reset(iter, cpu_file);
ftrace_enable_cpu();
p = s_next(m, p, &l);
}
+ trace_event_read_lock();
return p;
}
static void s_stop(struct seq_file *m, void *p)
{
atomic_dec(&trace_record_cmdline_disabled);
+ trace_event_read_unlock();
}
static void print_lat_help_header(struct seq_file *m)
seq_puts(m, "# | / _----=> need-resched \n");
seq_puts(m, "# || / _---=> hardirq/softirq \n");
seq_puts(m, "# ||| / _--=> preempt-depth \n");
- seq_puts(m, "# |||| / \n");
- seq_puts(m, "# ||||| delay \n");
- seq_puts(m, "# cmd pid ||||| time | caller \n");
- seq_puts(m, "# \\ / ||||| \\ | / \n");
+ seq_puts(m, "# |||| /_--=> lock-depth \n");
+ seq_puts(m, "# |||||/ delay \n");
+ seq_puts(m, "# cmd pid |||||| time | caller \n");
+ seq_puts(m, "# \\ / |||||| \\ | / \n");
}
static void print_func_help_header(struct seq_file *m)
struct trace_array *tr = iter->tr;
struct trace_array_cpu *data = tr->data[tr->cpu];
struct tracer *type = current_trace;
- unsigned long total;
- unsigned long entries;
+ unsigned long entries = 0;
+ unsigned long total = 0;
+ unsigned long count;
const char *name = "preemption";
+ int cpu;
if (type)
name = type->name;
- entries = ring_buffer_entries(iter->tr->buffer);
- total = entries +
- ring_buffer_overruns(iter->tr->buffer);
+
+ for_each_tracing_cpu(cpu) {
+ count = ring_buffer_entries_cpu(tr->buffer, cpu);
+ /*
+ * If this buffer has skipped entries, then we hold all
+ * entries for the trace and we need to ignore the
+ * ones before the time stamp.
+ */
+ if (tr->data[cpu]->skipped_entries) {
+ count -= tr->data[cpu]->skipped_entries;
+ /* total is the same as the entries */
+ total += count;
+ } else
+ total += count +
+ ring_buffer_overrun_cpu(tr->buffer, cpu);
+ entries += count;
+ }
seq_printf(m, "# %s latency trace v1.1.5 on %s\n",
name, UTS_RELEASE);
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#\n");
}
seq_puts(m, "#\n");
if (cpumask_test_cpu(iter->cpu, iter->started))
return;
+ if (iter->tr->data[iter->cpu]->skipped_entries)
+ return;
+
cpumask_set_cpu(iter->cpu, iter->started);
- trace_seq_printf(s, "##### CPU %u buffer started ####\n", iter->cpu);
+
+ /* 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)
return TRACE_TYPE_HANDLED;
}
-static enum print_line_t print_bprintk_msg_only(struct trace_iterator *iter)
-{
- struct trace_seq *s = &iter->seq;
- struct trace_entry *entry = iter->ent;
- struct bprint_entry *field;
- int ret;
-
- trace_assign_type(field, entry);
-
- ret = trace_seq_bprintf(s, field->fmt, field->buf);
- if (!ret)
- return TRACE_TYPE_PARTIAL_LINE;
-
- 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;
return 1;
}
+/* Called with trace_event_read_lock() held. */
static enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
if (iter->ent->type == TRACE_BPRINT &&
trace_flags & TRACE_ITER_PRINTK &&
trace_flags & TRACE_ITER_PRINTK_MSGONLY)
- return print_bprintk_msg_only(iter);
+ 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 (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
if (ring_buffer_overruns(iter->tr->buffer))
iter->iter_flags |= TRACE_FILE_ANNOTATE;
+ /* stop the trace while dumping */
+ tracing_stop();
+
if (iter->cpu_file == TRACE_PIPE_ALL_CPU) {
for_each_tracing_cpu(cpu) {
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
+ tracing_iter_reset(iter, cpu);
}
} else {
cpu = iter->cpu_file;
iter->buffer_iter[cpu] =
ring_buffer_read_start(iter->tr->buffer, cpu);
+ tracing_iter_reset(iter, cpu);
}
- /* TODO stop tracer */
ret = seq_open(file, &tracer_seq_ops);
if (ret < 0) {
fail_ret = ERR_PTR(ret);
m = file->private_data;
m->private = iter;
- /* stop the trace while dumping */
- tracing_stop();
-
mutex_unlock(&trace_types_lock);
return iter;
if (iter->buffer_iter[cpu])
ring_buffer_read_finish(iter->buffer_iter[cpu]);
}
+ free_cpumask_var(iter->started);
+ tracing_start();
fail:
mutex_unlock(&trace_types_lock);
kfree(iter->trace);
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])
seq_release(inode, file);
mutex_destroy(&iter->mutex);
+ free_cpumask_var(iter->started);
kfree(iter->trace);
kfree(iter);
return 0;
struct trace_iterator *iter;
int ret = 0;
- 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;
+ /* If this file was open for write, then erase contents */
+ if ((file->f_mode & FMODE_WRITE) &&
+ (file->f_flags & O_TRUNC)) {
+ long cpu = (long) inode->i_private;
+
+ 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)
{
- struct tracer *t = m->private;
+ struct tracer *t = v;
(*pos)++;
if (t)
t = t->next;
- m->private = t;
-
return t;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct tracer *t = m->private;
+ struct tracer *t;
loff_t l = 0;
mutex_lock(&trace_types_lock);
- for (; t && l < *pos; t = t_next(m, t, &l))
+ for (t = trace_types; t && l < *pos; t = t_next(m, t, &l))
;
return t;
static int show_traces_open(struct inode *inode, struct file *file)
{
- int ret;
-
if (tracing_disabled)
return -ENODEV;
- ret = seq_open(file, &show_traces_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = trace_types;
- }
+ return seq_open(file, &show_traces_seq_ops);
+}
- return ret;
+static ssize_t
+tracing_write_stub(struct file *filp, const char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ return count;
}
static const struct file_operations tracing_fops = {
.open = tracing_open,
.read = seq_read,
+ .write = tracing_write_stub,
.llseek = seq_lseek,
.release = tracing_release,
};
if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL))
return -ENOMEM;
- mutex_lock(&tracing_cpumask_update_lock);
err = cpumask_parse_user(ubuf, count, tracing_cpumask_new);
if (err)
goto err_unlock;
+ mutex_lock(&tracing_cpumask_update_lock);
+
local_irq_disable();
__raw_spin_lock(&ftrace_max_lock);
for_each_tracing_cpu(cpu) {
return count;
err_unlock:
- mutex_unlock(&tracing_cpumask_update_lock);
- free_cpumask_var(tracing_cpumask);
+ free_cpumask_var(tracing_cpumask_new);
return err;
}
len += 3; /* "no" and newline */
}
- /* +2 for \n and \0 */
- buf = kmalloc(len + 2, GFP_KERNEL);
+ /* +1 for \0 */
+ buf = kmalloc(len + 1, GFP_KERNEL);
if (!buf) {
mutex_unlock(&trace_types_lock);
return -ENOMEM;
}
mutex_unlock(&trace_types_lock);
- WARN_ON(r >= len + 2);
+ WARN_ON(r >= len + 1);
r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
/* Try to assign a tracer specific option */
static int set_tracer_option(struct tracer *trace, char *cmp, int neg)
{
- struct tracer_flags *trace_flags = trace->flags;
+ struct tracer_flags *tracer_flags = trace->flags;
struct tracer_opt *opts = NULL;
int ret = 0, i = 0;
int len;
- for (i = 0; trace_flags->opts[i].name; i++) {
- opts = &trace_flags->opts[i];
+ for (i = 0; tracer_flags->opts[i].name; i++) {
+ opts = &tracer_flags->opts[i];
len = strlen(opts->name);
if (strncmp(cmp, opts->name, len) == 0) {
- ret = trace->set_flag(trace_flags->val,
+ ret = trace->set_flag(tracer_flags->val,
opts->bit, !neg);
break;
}
}
/* Not found */
- if (!trace_flags->opts[i].name)
+ if (!tracer_flags->opts[i].name)
return -EINVAL;
/* Refused to handle */
return ret;
if (neg)
- trace_flags->val &= ~opts->bit;
+ tracer_flags->val &= ~opts->bit;
else
- trace_flags->val |= opts->bit;
+ tracer_flags->val |= opts->bit;
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;
+}
+
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;
}
}
static const char readme_msg[] =
"tracing mini-HOWTO:\n\n"
- "# 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"
- "# cat /debug/tracing/current_tracer\n"
- "none\n"
- "# echo sched_switch > /debug/tracing/current_tracer\n"
- "# cat /debug/tracing/current_tracer\n"
+ "# mount -t debugfs nodev /sys/kernel/debug\n\n"
+ "# cat /sys/kernel/debug/tracing/available_tracers\n"
+ "wakeup preemptirqsoff preemptoff irqsoff function sched_switch nop\n\n"
+ "# cat /sys/kernel/debug/tracing/current_tracer\n"
+ "nop\n"
+ "# echo sched_switch > /sys/kernel/debug/tracing/current_tracer\n"
+ "# cat /sys/kernel/debug/tracing/current_tracer\n"
"sched_switch\n"
- "# cat /debug/tracing/trace_options\n"
+ "# cat /sys/kernel/debug/tracing/trace_options\n"
"noprint-parent nosym-offset nosym-addr noverbose\n"
- "# echo print-parent > /debug/tracing/trace_options\n"
- "# echo 1 > /debug/tracing/tracing_enabled\n"
- "# cat /debug/tracing/trace > /tmp/trace.txt\n"
- "echo 0 > /debug/tracing/tracing_enabled\n"
+ "# echo print-parent > /sys/kernel/debug/tracing/trace_options\n"
+ "# echo 1 > /sys/kernel/debug/tracing/tracing_enabled\n"
+ "# cat /sys/kernel/debug/tracing/trace > /tmp/trace.txt\n"
+ "# echo 0 > /sys/kernel/debug/tracing/tracing_enabled\n"
;
static ssize_t
};
static ssize_t
+tracing_saved_cmdlines_read(struct file *file, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char *buf_comm;
+ char *file_buf;
+ char *buf;
+ int len = 0;
+ int pid;
+ int i;
+
+ file_buf = kmalloc(SAVED_CMDLINES*(16+TASK_COMM_LEN), GFP_KERNEL);
+ if (!file_buf)
+ return -ENOMEM;
+
+ buf_comm = kmalloc(TASK_COMM_LEN, GFP_KERNEL);
+ if (!buf_comm) {
+ kfree(file_buf);
+ return -ENOMEM;
+ }
+
+ buf = file_buf;
+
+ for (i = 0; i < SAVED_CMDLINES; i++) {
+ int r;
+
+ pid = map_cmdline_to_pid[i];
+ if (pid == -1 || pid == NO_CMDLINE_MAP)
+ continue;
+
+ trace_find_cmdline(pid, buf_comm);
+ r = sprintf(buf, "%d %s\n", pid, buf_comm);
+ buf += r;
+ len += r;
+ }
+
+ len = simple_read_from_buffer(ubuf, cnt, ppos,
+ file_buf, len);
+
+ kfree(file_buf);
+ kfree(buf_comm);
+
+ return len;
+}
+
+static const struct file_operations tracing_saved_cmdlines_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_saved_cmdlines_read,
+};
+
+static ssize_t
tracing_ctrl_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
if (!ring_buffer_expanded) {
ret = tracing_resize_ring_buffer(trace_buf_size);
if (ret < 0)
- return ret;
+ goto out;
ret = 0;
}
/* trace pipe does not show start of buffer */
cpumask_setall(iter->started);
+ if (trace_flags & TRACE_ITER_LATENCY_FMT)
+ iter->iter_flags |= TRACE_FILE_LAT_FMT;
+
iter->cpu_file = cpu_file;
iter->tr = &global_trace;
mutex_init(&iter->mutex);
offsetof(struct trace_iterator, seq));
iter->pos = -1;
+ trace_event_read_lock();
while (find_next_entry_inc(iter) != NULL) {
enum print_line_t ret;
int len = iter->seq.len;
if (iter->seq.len >= cnt)
break;
}
+ trace_event_read_unlock();
/* Now copy what we have to the user */
sret = trace_seq_to_user(&iter->seq, ubuf, cnt);
break;
}
- trace_consume(iter);
+ if (ret != TRACE_TYPE_NO_CONSUME)
+ trace_consume(iter);
rem -= count;
if (!find_next_entry_inc(iter)) {
rem = 0;
goto out_err;
}
+ trace_event_read_lock();
+
/* Fill as many pages as possible. */
for (i = 0, rem = len; i < PIPE_BUFFERS && rem; i++) {
pages[i] = alloc_page(GFP_KERNEL);
trace_seq_init(&iter->seq);
}
+ trace_event_read_unlock();
mutex_unlock(&iter->mutex);
spd.nr_pages = i;
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 ssize_t tracing_clock_read(struct file *filp, char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ char buf[64];
+ int bufiter = 0;
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(trace_clocks); i++)
+ bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter,
+ "%s%s%s%s", i ? " " : "",
+ i == trace_clock_id ? "[" : "", trace_clocks[i].name,
+ i == trace_clock_id ? "]" : "");
+ bufiter += snprintf(buf + bufiter, sizeof(buf) - bufiter, "\n");
+
+ return simple_read_from_buffer(ubuf, cnt, ppos, buf, bufiter);
+}
+
+static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *fpos)
+{
+ char buf[64];
+ const char *clockstr;
+ int i;
+
+ if (cnt >= sizeof(buf))
+ return -EINVAL;
+
+ if (copy_from_user(&buf, ubuf, cnt))
+ return -EFAULT;
+
+ buf[cnt] = 0;
+
+ clockstr = strstrip(buf);
+
+ for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) {
+ if (strcmp(trace_clocks[i].name, clockstr) == 0)
+ break;
+ }
+ if (i == ARRAY_SIZE(trace_clocks))
+ return -EINVAL;
+
+ trace_clock_id = i;
+
+ mutex_lock(&trace_types_lock);
+
+ ring_buffer_set_clock(global_trace.buffer, trace_clocks[i].func);
+ if (max_tr.buffer)
+ ring_buffer_set_clock(max_tr.buffer, trace_clocks[i].func);
+
+ mutex_unlock(&trace_types_lock);
+
+ *fpos += cnt;
+
+ return cnt;
+}
+
static const struct file_operations tracing_max_lat_fops = {
.open = tracing_open_generic,
.read = tracing_max_lat_read,
.write = tracing_mark_write,
};
+static const struct file_operations trace_clock_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_clock_read,
+ .write = tracing_clock_write,
+};
+
struct ftrace_buffer_info {
struct trace_array *tr;
void *spare;
info->tr = &global_trace;
info->cpu = cpu;
- info->spare = ring_buffer_alloc_read_page(info->tr->buffer);
+ info->spare = NULL;
/* 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;
+ return nonseekable_open(inode, filp);
}
static ssize_t
if (!count)
return 0;
+ if (!info->spare)
+ info->spare = ring_buffer_alloc_read_page(info->tr->buffer);
+ if (!info->spare)
+ return -ENOMEM;
+
/* Do we have previous read data to read? */
if (info->read < PAGE_SIZE)
goto read;
{
struct ftrace_buffer_info *info = file->private_data;
- ring_buffer_free_read_page(info->tr->buffer, info->spare);
+ if (info->spare)
+ ring_buffer_free_read_page(info->tr->buffer, info->spare);
kfree(info);
return 0;
.spd_release = buffer_spd_release,
};
struct buffer_ref *ref;
- int size, i;
+ int entries, size, i;
size_t ret;
- /*
- * We can't seek on a buffer input
- */
- if (unlikely(*ppos))
- return -ESPIPE;
+ if (*ppos & (PAGE_SIZE - 1)) {
+ WARN_ONCE(1, "Ftrace: previous read must page-align\n");
+ return -EINVAL;
+ }
+ if (len & (PAGE_SIZE - 1)) {
+ WARN_ONCE(1, "Ftrace: splice_read should page-align\n");
+ if (len < PAGE_SIZE)
+ return -EINVAL;
+ len &= PAGE_MASK;
+ }
+
+ entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
- for (i = 0; i < PIPE_BUFFERS && len; i++, len -= size) {
+ for (i = 0; i < PIPE_BUFFERS && len && entries; i++, len -= PAGE_SIZE) {
struct page *page;
int r;
if (!ref)
break;
+ ref->ref = 1;
ref->buffer = info->tr->buffer;
ref->page = ring_buffer_alloc_read_page(ref->buffer);
if (!ref->page) {
}
r = ring_buffer_read_page(ref->buffer, &ref->page,
- len, info->cpu, 0);
+ len, info->cpu, 1);
if (r < 0) {
ring_buffer_free_read_page(ref->buffer,
ref->page);
spd.partial[i].offset = 0;
spd.partial[i].private = (unsigned long)ref;
spd.nr_pages++;
+ *ppos += PAGE_SIZE;
+
+ entries = ring_buffer_entries_cpu(info->tr->buffer, info->cpu);
}
spd.nr_pages = i;
.llseek = no_llseek,
};
+static ssize_t
+tracing_stats_read(struct file *filp, char __user *ubuf,
+ size_t count, loff_t *ppos)
+{
+ unsigned long cpu = (unsigned long)filp->private_data;
+ struct trace_array *tr = &global_trace;
+ struct trace_seq *s;
+ unsigned long cnt;
+
+ s = kmalloc(sizeof(*s), GFP_KERNEL);
+ if (!s)
+ return ENOMEM;
+
+ trace_seq_init(s);
+
+ cnt = ring_buffer_entries_cpu(tr->buffer, cpu);
+ trace_seq_printf(s, "entries: %ld\n", cnt);
+
+ cnt = ring_buffer_overrun_cpu(tr->buffer, cpu);
+ trace_seq_printf(s, "overrun: %ld\n", cnt);
+
+ cnt = ring_buffer_commit_overrun_cpu(tr->buffer, cpu);
+ trace_seq_printf(s, "commit overrun: %ld\n", cnt);
+
+ count = simple_read_from_buffer(ubuf, count, ppos, s->buffer, s->len);
+
+ kfree(s);
+
+ return count;
+}
+
+static const struct file_operations tracing_stats_fops = {
+ .open = tracing_open_generic,
+ .read = tracing_stats_read,
+};
+
#ifdef CONFIG_DYNAMIC_FTRACE
int __weak ftrace_arch_read_dyn_info(char *buf, int size)
if (d_tracer)
return d_tracer;
+ if (!debugfs_initialized())
+ return NULL;
+
d_tracer = debugfs_create_dir("tracing", NULL);
if (!d_tracer && !once) {
static void tracing_init_debugfs_percpu(long cpu)
{
struct dentry *d_percpu = tracing_dentry_percpu();
- struct dentry *entry, *d_cpu;
+ struct dentry *d_cpu;
/* strlen(cpu) + MAX(log10(cpu)) + '\0' */
char cpu_dir[7];
}
/* 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");
+ trace_create_file("trace_pipe", 0444, d_cpu,
+ (void *) cpu, &tracing_pipe_fops);
/* per cpu trace */
- entry = debugfs_create_file("trace", 0444, d_cpu,
- (void *) cpu, &tracing_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'trace' entry\n");
+ trace_create_file("trace", 0644, d_cpu,
+ (void *) cpu, &tracing_fops);
+
+ trace_create_file("trace_pipe_raw", 0444, d_cpu,
+ (void *) cpu, &tracing_buffers_fops);
- 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");
+ trace_create_file("stats", 0444, d_cpu,
+ (void *) cpu, &tracing_stats_fops);
}
#ifdef CONFIG_FTRACE_SELFTEST
if (ret < 0)
return ret;
- switch (val) {
- case 0:
- trace_flags &= ~(1 << index);
- break;
- case 1:
- trace_flags |= 1 << index;
- break;
-
- default:
+ if (val != 0 && val != 1)
return -EINVAL;
- }
+ set_tracer_flags(1 << index, val);
*ppos += cnt;
.write = trace_options_core_write,
};
+struct dentry *trace_create_file(const char *name,
+ mode_t mode,
+ struct dentry *parent,
+ void *data,
+ const struct file_operations *fops)
+{
+ struct dentry *ret;
+
+ ret = debugfs_create_file(name, mode, parent, data, fops);
+ if (!ret)
+ pr_warning("Could not create debugfs '%s' entry\n", name);
+
+ return ret;
+}
+
+
static struct dentry *trace_options_init_dentry(void)
{
struct dentry *d_tracer;
struct tracer_opt *opt)
{
struct dentry *t_options;
- struct dentry *entry;
t_options = trace_options_init_dentry();
if (!t_options)
topt->flags = flags;
topt->opt = opt;
- entry = debugfs_create_file(opt->name, 0644, t_options, topt,
+ topt->entry = trace_create_file(opt->name, 0644, t_options, topt,
&trace_options_fops);
- topt->entry = entry;
-
}
static struct trace_option_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,
+ return trace_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]);
- }
+ for (i = 0; trace_options[i]; i++)
+ create_trace_option_core_file(trace_options[i], 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");
+ trace_create_file("tracing_enabled", 0644, d_tracer,
+ &global_trace, &tracing_ctrl_fops);
- 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");
+ trace_create_file("trace_options", 0644, d_tracer,
+ NULL, &tracing_iter_fops);
- create_trace_options_dir();
+ trace_create_file("tracing_cpumask", 0644, d_tracer,
+ NULL, &tracing_cpumask_fops);
+
+ trace_create_file("trace", 0644, d_tracer,
+ (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
+
+ trace_create_file("available_tracers", 0444, d_tracer,
+ &global_trace, &show_traces_fops);
+
+ trace_create_file("current_tracer", 0644, d_tracer,
+ &global_trace, &set_tracer_fops);
- 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("trace", 0444, d_tracer,
- (void *) TRACE_PIPE_ALL_CPU, &tracing_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'trace' entry\n");
-
- entry = debugfs_create_file("available_tracers", 0444, d_tracer,
- &global_trace, &show_traces_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'available_tracers' entry\n");
-
- entry = debugfs_create_file("current_tracer", 0444, d_tracer,
- &global_trace, &set_tracer_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'current_tracer' entry\n");
-
- entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer,
- &tracing_max_latency,
- &tracing_max_lat_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'tracing_max_latency' entry\n");
-
- entry = debugfs_create_file("tracing_thresh", 0644, d_tracer,
- &tracing_thresh, &tracing_max_lat_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'tracing_thresh' entry\n");
- entry = debugfs_create_file("README", 0644, d_tracer,
- NULL, &tracing_readme_fops);
- if (!entry)
- pr_warning("Could not create debugfs 'README' entry\n");
-
- entry = debugfs_create_file("trace_pipe", 0444, d_tracer,
+#ifdef CONFIG_TRACER_MAX_TRACE
+ trace_create_file("tracing_max_latency", 0644, d_tracer,
+ &tracing_max_latency, &tracing_max_lat_fops);
+
+ trace_create_file("tracing_thresh", 0644, d_tracer,
+ &tracing_thresh, &tracing_max_lat_fops);
+#endif
+
+ trace_create_file("README", 0444, d_tracer,
+ NULL, &tracing_readme_fops);
+
+ trace_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");
-
- entry = debugfs_create_file("buffer_size_kb", 0644, d_tracer,
- &global_trace, &tracing_entries_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'buffer_size_kb' entry\n");
-
- entry = debugfs_create_file("trace_marker", 0220, d_tracer,
- NULL, &tracing_mark_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'trace_marker' entry\n");
+
+ trace_create_file("buffer_size_kb", 0644, d_tracer,
+ &global_trace, &tracing_entries_fops);
+
+ trace_create_file("trace_marker", 0220, d_tracer,
+ NULL, &tracing_mark_fops);
+
+ trace_create_file("saved_cmdlines", 0444, d_tracer,
+ NULL, &tracing_saved_cmdlines_fops);
+
+ trace_create_file("trace_clock", 0644, d_tracer, NULL,
+ &trace_clock_fops);
#ifdef CONFIG_DYNAMIC_FTRACE
- entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer,
- &ftrace_update_tot_cnt,
- &tracing_dyn_info_fops);
- if (!entry)
- pr_warning("Could not create debugfs "
- "'dyn_ftrace_total_info' entry\n");
+ trace_create_file("dyn_ftrace_total_info", 0444, d_tracer,
+ &ftrace_update_tot_cnt, &tracing_dyn_info_fops);
#endif
#ifdef CONFIG_SYSPROF_TRACER
init_tracer_sysprof_debugfs(d_tracer);
#endif
+ create_trace_options_dir();
+
for_each_tracing_cpu(cpu)
tracing_init_debugfs_percpu(cpu);
trace_seq_init(s);
}
-void ftrace_dump(void)
+static void __ftrace_dump(bool disable_tracing)
{
- static DEFINE_SPINLOCK(ftrace_dump_lock);
+ static raw_spinlock_t ftrace_dump_lock =
+ (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED;
/* 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;
/* only one dump */
- spin_lock_irqsave(&ftrace_dump_lock, flags);
+ local_irq_save(flags);
+ __raw_spin_lock(&ftrace_dump_lock);
if (dump_ran)
goto out;
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;
iter.pos = -1;
if (find_next_entry_inc(&iter) != NULL) {
- print_trace_line(&iter);
- trace_consume(&iter);
+ int ret;
+
+ ret = print_trace_line(&iter);
+ if (ret != TRACE_TYPE_NO_CONSUME)
+ trace_consume(&iter);
}
trace_printk_seq(&iter.seq);
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);
+ __raw_spin_unlock(&ftrace_dump_lock);
+ local_irq_restore(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;
/* Allocate the first page for all buffers */
for_each_tracing_cpu(i) {
- data = global_trace.data[i] = &per_cpu(global_trace_cpu, i);
+ global_trace.data[i] = &per_cpu(global_trace_cpu, i);
max_tr.data[i] = &per_cpu(max_data, i);
}
&trace_panic_notifier);
register_die_notifier(&trace_die_notifier);
- ret = 0;
+
+ return 0;
out_free_cpumask:
free_cpumask_var(tracing_reader_cpumask);