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-rw-r--r--drivers/oprofile/cpu_buffer.c4
-rw-r--r--include/linux/ftrace_event.h1
-rw-r--r--include/linux/module.h6
-rw-r--r--include/linux/ring_buffer.h6
-rw-r--r--include/trace/events/module.h18
-rw-r--r--include/trace/events/signal.h52
-rw-r--r--include/trace/ftrace.h33
-rw-r--r--kernel/module.c8
-rw-r--r--kernel/trace/ring_buffer.c101
-rw-r--r--kernel/trace/ring_buffer_benchmark.c2
-rw-r--r--kernel/trace/trace.c30
-rw-r--r--kernel/trace/trace_functions_graph.c5
-rw-r--r--kernel/trace/trace_selftest.c2
13 files changed, 187 insertions, 81 deletions
diff --git a/drivers/oprofile/cpu_buffer.c b/drivers/oprofile/cpu_buffer.c
index 166b67ea622..7581dbe456d 100644
--- a/drivers/oprofile/cpu_buffer.c
+++ b/drivers/oprofile/cpu_buffer.c
@@ -186,14 +186,14 @@ int op_cpu_buffer_write_commit(struct op_entry *entry)
struct op_sample *op_cpu_buffer_read_entry(struct op_entry *entry, int cpu)
{
struct ring_buffer_event *e;
- e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+ e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL, NULL);
if (e)
goto event;
if (ring_buffer_swap_cpu(op_ring_buffer_read,
op_ring_buffer_write,
cpu))
return NULL;
- e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL);
+ e = ring_buffer_consume(op_ring_buffer_read, cpu, NULL, NULL);
if (e)
goto event;
return NULL;
diff --git a/include/linux/ftrace_event.h b/include/linux/ftrace_event.h
index c0f4b364c71..39e71b0a3bf 100644
--- a/include/linux/ftrace_event.h
+++ b/include/linux/ftrace_event.h
@@ -58,6 +58,7 @@ struct trace_iterator {
/* The below is zeroed out in pipe_read */
struct trace_seq seq;
struct trace_entry *ent;
+ unsigned long lost_events;
int leftover;
int cpu;
u64 ts;
diff --git a/include/linux/module.h b/include/linux/module.h
index 515d53ae6a7..6914fcad467 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -465,8 +465,7 @@ static inline void __module_get(struct module *module)
if (module) {
preempt_disable();
__this_cpu_inc(module->refptr->incs);
- trace_module_get(module, _THIS_IP_,
- __this_cpu_read(module->refptr->incs));
+ trace_module_get(module, _THIS_IP_);
preempt_enable();
}
}
@@ -480,8 +479,7 @@ static inline int try_module_get(struct module *module)
if (likely(module_is_live(module))) {
__this_cpu_inc(module->refptr->incs);
- trace_module_get(module, _THIS_IP_,
- __this_cpu_read(module->refptr->incs));
+ trace_module_get(module, _THIS_IP_);
} else
ret = 0;
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index 5fcc31ed577..c8297761e41 100644
--- a/include/linux/ring_buffer.h
+++ b/include/linux/ring_buffer.h
@@ -120,9 +120,11 @@ int ring_buffer_write(struct ring_buffer *buffer,
unsigned long length, void *data);
struct ring_buffer_event *
-ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts);
+ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
+ unsigned long *lost_events);
struct ring_buffer_event *
-ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts);
+ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
+ unsigned long *lost_events);
struct ring_buffer_iter *
ring_buffer_read_start(struct ring_buffer *buffer, int cpu);
diff --git a/include/trace/events/module.h b/include/trace/events/module.h
index 4b0f48ba16a..c7bb2f0482f 100644
--- a/include/trace/events/module.h
+++ b/include/trace/events/module.h
@@ -51,11 +51,14 @@ TRACE_EVENT(module_free,
TP_printk("%s", __get_str(name))
);
+#ifdef CONFIG_MODULE_UNLOAD
+/* trace_module_get/put are only used if CONFIG_MODULE_UNLOAD is defined */
+
DECLARE_EVENT_CLASS(module_refcnt,
- TP_PROTO(struct module *mod, unsigned long ip, int refcnt),
+ TP_PROTO(struct module *mod, unsigned long ip),
- TP_ARGS(mod, ip, refcnt),
+ TP_ARGS(mod, ip),
TP_STRUCT__entry(
__field( unsigned long, ip )
@@ -65,7 +68,7 @@ DECLARE_EVENT_CLASS(module_refcnt,
TP_fast_assign(
__entry->ip = ip;
- __entry->refcnt = refcnt;
+ __entry->refcnt = __this_cpu_read(mod->refptr->incs) + __this_cpu_read(mod->refptr->decs);
__assign_str(name, mod->name);
),
@@ -75,17 +78,18 @@ DECLARE_EVENT_CLASS(module_refcnt,
DEFINE_EVENT(module_refcnt, module_get,
- TP_PROTO(struct module *mod, unsigned long ip, int refcnt),
+ TP_PROTO(struct module *mod, unsigned long ip),
- TP_ARGS(mod, ip, refcnt)
+ TP_ARGS(mod, ip)
);
DEFINE_EVENT(module_refcnt, module_put,
- TP_PROTO(struct module *mod, unsigned long ip, int refcnt),
+ TP_PROTO(struct module *mod, unsigned long ip),
- TP_ARGS(mod, ip, refcnt)
+ TP_ARGS(mod, ip)
);
+#endif /* CONFIG_MODULE_UNLOAD */
TRACE_EVENT(module_request,
diff --git a/include/trace/events/signal.h b/include/trace/events/signal.h
index a510b75ac30..814566c99d2 100644
--- a/include/trace/events/signal.h
+++ b/include/trace/events/signal.h
@@ -100,18 +100,7 @@ TRACE_EVENT(signal_deliver,
__entry->sa_handler, __entry->sa_flags)
);
-/**
- * signal_overflow_fail - called when signal queue is overflow
- * @sig: signal number
- * @group: signal to process group or not (bool)
- * @info: pointer to struct siginfo
- *
- * Kernel fails to generate 'sig' signal with 'info' siginfo, because
- * siginfo queue is overflow, and the signal is dropped.
- * 'group' is not 0 if the signal will be sent to a process group.
- * 'sig' is always one of RT signals.
- */
-TRACE_EVENT(signal_overflow_fail,
+DECLARE_EVENT_CLASS(signal_queue_overflow,
TP_PROTO(int sig, int group, struct siginfo *info),
@@ -135,6 +124,24 @@ TRACE_EVENT(signal_overflow_fail,
);
/**
+ * signal_overflow_fail - called when signal queue is overflow
+ * @sig: signal number
+ * @group: signal to process group or not (bool)
+ * @info: pointer to struct siginfo
+ *
+ * Kernel fails to generate 'sig' signal with 'info' siginfo, because
+ * siginfo queue is overflow, and the signal is dropped.
+ * 'group' is not 0 if the signal will be sent to a process group.
+ * 'sig' is always one of RT signals.
+ */
+DEFINE_EVENT(signal_queue_overflow, signal_overflow_fail,
+
+ TP_PROTO(int sig, int group, struct siginfo *info),
+
+ TP_ARGS(sig, group, info)
+);
+
+/**
* signal_lose_info - called when siginfo is lost
* @sig: signal number
* @group: signal to process group or not (bool)
@@ -145,28 +152,13 @@ TRACE_EVENT(signal_overflow_fail,
* 'group' is not 0 if the signal will be sent to a process group.
* 'sig' is always one of non-RT signals.
*/
-TRACE_EVENT(signal_lose_info,
+DEFINE_EVENT(signal_queue_overflow, signal_lose_info,
TP_PROTO(int sig, int group, struct siginfo *info),
- TP_ARGS(sig, group, info),
-
- TP_STRUCT__entry(
- __field( int, sig )
- __field( int, group )
- __field( int, errno )
- __field( int, code )
- ),
-
- TP_fast_assign(
- __entry->sig = sig;
- __entry->group = group;
- TP_STORE_SIGINFO(__entry, info);
- ),
-
- TP_printk("sig=%d group=%d errno=%d code=%d",
- __entry->sig, __entry->group, __entry->errno, __entry->code)
+ TP_ARGS(sig, group, info)
);
+
#endif /* _TRACE_SIGNAL_H */
/* This part must be outside protection */
diff --git a/include/trace/ftrace.h b/include/trace/ftrace.h
index ea6f9d4a20e..75dd7787fb3 100644
--- a/include/trace/ftrace.h
+++ b/include/trace/ftrace.h
@@ -154,9 +154,11 @@
*
* field = (typeof(field))entry;
*
- * p = get_cpu_var(ftrace_event_seq);
+ * p = &get_cpu_var(ftrace_event_seq);
* trace_seq_init(p);
- * ret = trace_seq_printf(s, <TP_printk> "\n");
+ * ret = trace_seq_printf(s, "%s: ", <call>);
+ * if (ret)
+ * ret = trace_seq_printf(s, <TP_printk> "\n");
* put_cpu();
* if (!ret)
* return TRACE_TYPE_PARTIAL_LINE;
@@ -450,38 +452,38 @@ perf_trace_disable_##name(struct ftrace_event_call *unused) \
*
* static void ftrace_raw_event_<call>(proto)
* {
+ * struct ftrace_data_offsets_<call> __maybe_unused __data_offsets;
* struct ring_buffer_event *event;
* struct ftrace_raw_<call> *entry; <-- defined in stage 1
* struct ring_buffer *buffer;
* unsigned long irq_flags;
+ * int __data_size;
* int pc;
*
* local_save_flags(irq_flags);
* pc = preempt_count();
*
+ * __data_size = ftrace_get_offsets_<call>(&__data_offsets, args);
+ *
* event = trace_current_buffer_lock_reserve(&buffer,
* event_<call>.id,
- * sizeof(struct ftrace_raw_<call>),
+ * sizeof(*entry) + __data_size,
* irq_flags, pc);
* if (!event)
* return;
* entry = ring_buffer_event_data(event);
*
- * <assign>; <-- Here we assign the entries by the __field and
- * __array macros.
+ * { <assign>; } <-- Here we assign the entries by the __field and
+ * __array macros.
*
- * trace_current_buffer_unlock_commit(buffer, event, irq_flags, pc);
+ * if (!filter_current_check_discard(buffer, event_call, entry, event))
+ * trace_current_buffer_unlock_commit(buffer,
+ * event, irq_flags, pc);
* }
*
* static int ftrace_raw_reg_event_<call>(struct ftrace_event_call *unused)
* {
- * int ret;
- *
- * ret = register_trace_<call>(ftrace_raw_event_<call>);
- * if (!ret)
- * pr_info("event trace: Could not activate trace point "
- * "probe to <call>");
- * return ret;
+ * return register_trace_<call>(ftrace_raw_event_<call>);
* }
*
* static void ftrace_unreg_event_<call>(struct ftrace_event_call *unused)
@@ -493,6 +495,8 @@ perf_trace_disable_##name(struct ftrace_event_call *unused) \
* .trace = ftrace_raw_output_<call>, <-- stage 2
* };
*
+ * static const char print_fmt_<call>[] = <TP_printk>;
+ *
* static struct ftrace_event_call __used
* __attribute__((__aligned__(4)))
* __attribute__((section("_ftrace_events"))) event_<call> = {
@@ -501,6 +505,8 @@ perf_trace_disable_##name(struct ftrace_event_call *unused) \
* .raw_init = trace_event_raw_init,
* .regfunc = ftrace_reg_event_<call>,
* .unregfunc = ftrace_unreg_event_<call>,
+ * .print_fmt = print_fmt_<call>,
+ * .define_fields = ftrace_define_fields_<call>,
* }
*
*/
@@ -569,7 +575,6 @@ ftrace_raw_event_id_##call(struct ftrace_event_call *event_call, \
return; \
entry = ring_buffer_event_data(event); \
\
- \
tstruct \
\
{ assign; } \
diff --git a/kernel/module.c b/kernel/module.c
index 1016b75b026..b8a1e313448 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -59,8 +59,6 @@
#define CREATE_TRACE_POINTS
#include <trace/events/module.h>
-EXPORT_TRACEPOINT_SYMBOL(module_get);
-
#if 0
#define DEBUGP printk
#else
@@ -515,6 +513,9 @@ MODINFO_ATTR(srcversion);
static char last_unloaded_module[MODULE_NAME_LEN+1];
#ifdef CONFIG_MODULE_UNLOAD
+
+EXPORT_TRACEPOINT_SYMBOL(module_get);
+
/* Init the unload section of the module. */
static void module_unload_init(struct module *mod)
{
@@ -867,8 +868,7 @@ void module_put(struct module *module)
smp_wmb(); /* see comment in module_refcount */
__this_cpu_inc(module->refptr->decs);
- trace_module_put(module, _RET_IP_,
- __this_cpu_read(module->refptr->decs));
+ trace_module_put(module, _RET_IP_);
/* Maybe they're waiting for us to drop reference? */
if (unlikely(!module_is_live(module)))
wake_up_process(module->waiter);
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 41ca394feb2..5885cdfc41f 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -319,6 +319,11 @@ EXPORT_SYMBOL_GPL(ring_buffer_event_data);
#define TS_MASK ((1ULL << TS_SHIFT) - 1)
#define TS_DELTA_TEST (~TS_MASK)
+/* Flag when events were overwritten */
+#define RB_MISSED_EVENTS (1 << 31)
+/* Missed count stored at end */
+#define RB_MISSED_STORED (1 << 30)
+
struct buffer_data_page {
u64 time_stamp; /* page time stamp */
local_t commit; /* write committed index */
@@ -338,6 +343,7 @@ struct buffer_page {
local_t write; /* index for next write */
unsigned read; /* index for next read */
local_t entries; /* entries on this page */
+ unsigned long real_end; /* real end of data */
struct buffer_data_page *page; /* Actual data page */
};
@@ -417,6 +423,12 @@ int ring_buffer_print_page_header(struct trace_seq *s)
(unsigned int)sizeof(field.commit),
(unsigned int)is_signed_type(long));
+ ret = trace_seq_printf(s, "\tfield: int overwrite;\t"
+ "offset:%u;\tsize:%u;\tsigned:%u;\n",
+ (unsigned int)offsetof(typeof(field), commit),
+ 1,
+ (unsigned int)is_signed_type(long));
+
ret = trace_seq_printf(s, "\tfield: char data;\t"
"offset:%u;\tsize:%u;\tsigned:%u;\n",
(unsigned int)offsetof(typeof(field), data),
@@ -440,6 +452,8 @@ struct ring_buffer_per_cpu {
struct buffer_page *tail_page; /* write to tail */
struct buffer_page *commit_page; /* committed pages */
struct buffer_page *reader_page;
+ unsigned long lost_events;
+ unsigned long last_overrun;
local_t commit_overrun;
local_t overrun;
local_t entries;
@@ -1762,6 +1776,13 @@ rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
kmemcheck_annotate_bitfield(event, bitfield);
/*
+ * Save the original length to the meta data.
+ * This will be used by the reader to add lost event
+ * counter.
+ */
+ tail_page->real_end = tail;
+
+ /*
* If this event is bigger than the minimum size, then
* we need to be careful that we don't subtract the
* write counter enough to allow another writer to slip
@@ -2838,6 +2859,7 @@ static struct buffer_page *
rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
{
struct buffer_page *reader = NULL;
+ unsigned long overwrite;
unsigned long flags;
int nr_loops = 0;
int ret;
@@ -2879,6 +2901,7 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
local_set(&cpu_buffer->reader_page->write, 0);
local_set(&cpu_buffer->reader_page->entries, 0);
local_set(&cpu_buffer->reader_page->page->commit, 0);
+ cpu_buffer->reader_page->real_end = 0;
spin:
/*
@@ -2899,6 +2922,18 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
rb_set_list_to_head(cpu_buffer, &cpu_buffer->reader_page->list);
/*
+ * We want to make sure we read the overruns after we set up our
+ * pointers to the next object. The writer side does a
+ * cmpxchg to cross pages which acts as the mb on the writer
+ * side. Note, the reader will constantly fail the swap
+ * while the writer is updating the pointers, so this
+ * guarantees that the overwrite recorded here is the one we
+ * want to compare with the last_overrun.
+ */
+ smp_mb();
+ overwrite = local_read(&(cpu_buffer->overrun));
+
+ /*
* Here's the tricky part.
*
* We need to move the pointer past the header page.
@@ -2929,6 +2964,11 @@ rb_get_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->reader_page = reader;
rb_reset_reader_page(cpu_buffer);
+ if (overwrite != cpu_buffer->last_overrun) {
+ cpu_buffer->lost_events = overwrite - cpu_buffer->last_overrun;
+ cpu_buffer->last_overrun = overwrite;
+ }
+
goto again;
out:
@@ -3005,8 +3045,14 @@ static void rb_advance_iter(struct ring_buffer_iter *iter)
rb_advance_iter(iter);
}
+static int rb_lost_events(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ return cpu_buffer->lost_events;
+}
+
static struct ring_buffer_event *
-rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
+rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts,
+ unsigned long *lost_events)
{
struct ring_buffer_event *event;
struct buffer_page *reader;
@@ -3058,6 +3104,8 @@ rb_buffer_peek(struct ring_buffer_per_cpu *cpu_buffer, u64 *ts)
ring_buffer_normalize_time_stamp(cpu_buffer->buffer,
cpu_buffer->cpu, ts);
}
+ if (lost_events)
+ *lost_events = rb_lost_events(cpu_buffer);
return event;
default:
@@ -3168,12 +3216,14 @@ static inline int rb_ok_to_lock(void)
* @buffer: The ring buffer to read
* @cpu: The cpu to peak at
* @ts: The timestamp counter of this event.
+ * @lost_events: a variable to store if events were lost (may be NULL)
*
* This will return the event that will be read next, but does
* not consume the data.
*/
struct ring_buffer_event *
-ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
+ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts,
+ unsigned long *lost_events)
{
struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
struct ring_buffer_event *event;
@@ -3188,7 +3238,7 @@ ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts)
local_irq_save(flags);
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
- event = rb_buffer_peek(cpu_buffer, ts);
+ event = rb_buffer_peek(cpu_buffer, ts, lost_events);
if (event && event->type_len == RINGBUF_TYPE_PADDING)
rb_advance_reader(cpu_buffer);
if (dolock)
@@ -3230,13 +3280,17 @@ ring_buffer_iter_peek(struct ring_buffer_iter *iter, u64 *ts)
/**
* ring_buffer_consume - return an event and consume it
* @buffer: The ring buffer to get the next event from
+ * @cpu: the cpu to read the buffer from
+ * @ts: a variable to store the timestamp (may be NULL)
+ * @lost_events: a variable to store if events were lost (may be NULL)
*
* Returns the next event in the ring buffer, and that event is consumed.
* Meaning, that sequential reads will keep returning a different event,
* and eventually empty the ring buffer if the producer is slower.
*/
struct ring_buffer_event *
-ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
+ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts,
+ unsigned long *lost_events)
{
struct ring_buffer_per_cpu *cpu_buffer;
struct ring_buffer_event *event = NULL;
@@ -3257,9 +3311,11 @@ ring_buffer_consume(struct ring_buffer *buffer, int cpu, u64 *ts)
if (dolock)
spin_lock(&cpu_buffer->reader_lock);
- event = rb_buffer_peek(cpu_buffer, ts);
- if (event)
+ event = rb_buffer_peek(cpu_buffer, ts, lost_events);
+ if (event) {
+ cpu_buffer->lost_events = 0;
rb_advance_reader(cpu_buffer);
+ }
if (dolock)
spin_unlock(&cpu_buffer->reader_lock);
@@ -3408,6 +3464,9 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->write_stamp = 0;
cpu_buffer->read_stamp = 0;
+ cpu_buffer->lost_events = 0;
+ cpu_buffer->last_overrun = 0;
+
rb_head_page_activate(cpu_buffer);
}
@@ -3683,6 +3742,7 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
struct ring_buffer_event *event;
struct buffer_data_page *bpage;
struct buffer_page *reader;
+ unsigned long missed_events;
unsigned long flags;
unsigned int commit;
unsigned int read;
@@ -3719,6 +3779,9 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
read = reader->read;
commit = rb_page_commit(reader);
+ /* Check if any events were dropped */
+ missed_events = cpu_buffer->lost_events;
+
/*
* If this page has been partially read or
* if len is not big enough to read the rest of the page or
@@ -3779,9 +3842,35 @@ int ring_buffer_read_page(struct ring_buffer *buffer,
local_set(&reader->entries, 0);
reader->read = 0;
*data_page = bpage;
+
+ /*
+ * Use the real_end for the data size,
+ * This gives us a chance to store the lost events
+ * on the page.
+ */
+ if (reader->real_end)
+ local_set(&bpage->commit, reader->real_end);
}
ret = read;
+ cpu_buffer->lost_events = 0;
+ /*
+ * Set a flag in the commit field if we lost events
+ */
+ if (missed_events) {
+ commit = local_read(&bpage->commit);
+
+ /* If there is room at the end of the page to save the
+ * missed events, then record it there.
+ */
+ if (BUF_PAGE_SIZE - commit >= sizeof(missed_events)) {
+ memcpy(&bpage->data[commit], &missed_events,
+ sizeof(missed_events));
+ local_add(RB_MISSED_STORED, &bpage->commit);
+ }
+ local_add(RB_MISSED_EVENTS, &bpage->commit);
+ }
+
out_unlock:
spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
diff --git a/kernel/trace/ring_buffer_benchmark.c b/kernel/trace/ring_buffer_benchmark.c
index df74c798225..dc56556b55a 100644
--- a/kernel/trace/ring_buffer_benchmark.c
+++ b/kernel/trace/ring_buffer_benchmark.c
@@ -81,7 +81,7 @@ static enum event_status read_event(int cpu)
int *entry;
u64 ts;
- event = ring_buffer_consume(buffer, cpu, &ts);
+ event = ring_buffer_consume(buffer, cpu, &ts, NULL);
if (!event)
return EVENT_DROPPED;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 44f916a0406..60f3b628973 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1545,7 +1545,8 @@ static void trace_iterator_increment(struct trace_iterator *iter)
}
static struct trace_entry *
-peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
+peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts,
+ unsigned long *lost_events)
{
struct ring_buffer_event *event;
struct ring_buffer_iter *buf_iter = iter->buffer_iter[cpu];
@@ -1556,7 +1557,8 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
if (buf_iter)
event = ring_buffer_iter_peek(buf_iter, ts);
else
- event = ring_buffer_peek(iter->tr->buffer, cpu, ts);
+ event = ring_buffer_peek(iter->tr->buffer, cpu, ts,
+ lost_events);
ftrace_enable_cpu();
@@ -1564,10 +1566,12 @@ peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts)
}
static struct trace_entry *
-__find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
+__find_next_entry(struct trace_iterator *iter, int *ent_cpu,
+ unsigned long *missing_events, u64 *ent_ts)
{
struct ring_buffer *buffer = iter->tr->buffer;
struct trace_entry *ent, *next = NULL;
+ unsigned long lost_events, next_lost = 0;
int cpu_file = iter->cpu_file;
u64 next_ts = 0, ts;
int next_cpu = -1;
@@ -1580,7 +1584,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
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);
+ ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events);
if (ent_cpu)
*ent_cpu = cpu_file;
@@ -1592,7 +1596,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
if (ring_buffer_empty_cpu(buffer, cpu))
continue;
- ent = peek_next_entry(iter, cpu, &ts);
+ ent = peek_next_entry(iter, cpu, &ts, &lost_events);
/*
* Pick the entry with the smallest timestamp:
@@ -1601,6 +1605,7 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
next = ent;
next_cpu = cpu;
next_ts = ts;
+ next_lost = lost_events;
}
}
@@ -1610,6 +1615,9 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
if (ent_ts)
*ent_ts = next_ts;
+ if (missing_events)
+ *missing_events = next_lost;
+
return next;
}
@@ -1617,13 +1625,14 @@ __find_next_entry(struct trace_iterator *iter, int *ent_cpu, u64 *ent_ts)
struct trace_entry *trace_find_next_entry(struct trace_iterator *iter,
int *ent_cpu, u64 *ent_ts)
{
- return __find_next_entry(iter, ent_cpu, ent_ts);
+ return __find_next_entry(iter, ent_cpu, NULL, ent_ts);
}
/* Find the next real entry, and increment the iterator to the next entry */
static void *find_next_entry_inc(struct trace_iterator *iter)
{
- iter->ent = __find_next_entry(iter, &iter->cpu, &iter->ts);
+ iter->ent = __find_next_entry(iter, &iter->cpu,
+ &iter->lost_events, &iter->ts);
if (iter->ent)
trace_iterator_increment(iter);
@@ -1635,7 +1644,8 @@ static void trace_consume(struct trace_iterator *iter)
{
/* Don't allow ftrace to trace into the ring buffers */
ftrace_disable_cpu();
- ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts);
+ ring_buffer_consume(iter->tr->buffer, iter->cpu, &iter->ts,
+ &iter->lost_events);
ftrace_enable_cpu();
}
@@ -2030,6 +2040,10 @@ static enum print_line_t print_trace_line(struct trace_iterator *iter)
{
enum print_line_t ret;
+ if (iter->lost_events)
+ trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n",
+ iter->cpu, iter->lost_events);
+
if (iter->trace && iter->trace->print_line) {
ret = iter->trace->print_line(iter);
if (ret != TRACE_TYPE_UNHANDLED)
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 9aed1a5cf55..669b9c31861 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -490,9 +490,10 @@ get_return_for_leaf(struct trace_iterator *iter,
* We need to consume the current entry to see
* the next one.
*/
- ring_buffer_consume(iter->tr->buffer, iter->cpu, NULL);
+ ring_buffer_consume(iter->tr->buffer, iter->cpu,
+ NULL, NULL);
event = ring_buffer_peek(iter->tr->buffer, iter->cpu,
- NULL);
+ NULL, NULL);
}
if (!event)
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 81003b4d617..9398034f814 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -30,7 +30,7 @@ static int trace_test_buffer_cpu(struct trace_array *tr, int cpu)
struct trace_entry *entry;
unsigned int loops = 0;
- while ((event = ring_buffer_consume(tr->buffer, cpu, NULL))) {
+ while ((event = ring_buffer_consume(tr->buffer, cpu, NULL, NULL))) {
entry = ring_buffer_event_data(event);
/*