Merge tag 'trace-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing update from Steven Rostedt:
"Mostly this is just clean ups and micro optimizations.
The changes with more meat are:
- Allowing the trace event filters to filter on CPU number and
process ids
- Two new markers for trace output latency were added (10 and 100
msec latencies)
- Have tracing_thresh filter function profiling time
I also worked on modifying the ring buffer code for some future work,
and moved the adding of the timestamp around. One of my changes
caused a regression, and since other changes were built on top of it
and already tested, I had to operate a revert of that change. Instead
of rebasing, this change set has the code that caused a regression as
well as the code to revert that change without touching the other
changes that were made on top of it"
* tag 'trace-v4.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ring-buffer: Revert "ring-buffer: Get timestamp after event is allocated"
tracing: Don't make assumptions about length of string on task rename
tracing: Allow triggers to filter for CPU ids and process names
ftrace: Format MCOUNT_ADDR address as type unsigned long
tracing: Introduce two additional marks for delay
ftrace: Fix function_graph duration spacing with 7-digits
ftrace: add tracing_thresh to function profile
tracing: Clean up stack tracing and fix fentry updates
ring-buffer: Reorganize function locations
ring-buffer: Make sure event has enough room for extend and padding
ring-buffer: Get timestamp after event is allocated
ring-buffer: Move the adding of the extended timestamp out of line
ring-buffer: Add event descriptor to simplify passing data
ftrace: correct the counter increment for trace_buffer data
tracing: Fix for non-continuous cpu ids
tracing: Prefer kcalloc over kzalloc with multiply
diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt
index 87bb4aa..ef621d3 100644
--- a/Documentation/trace/ftrace.txt
+++ b/Documentation/trace/ftrace.txt
@@ -691,6 +691,8 @@
The marks are determined by the difference between this
current trace and the next trace.
'$' - greater than 1 second
+ '@' - greater than 100 milisecond
+ '*' - greater than 10 milisecond
'#' - greater than 1000 microsecond
'!' - greater than 100 microsecond
'+' - greater than 10 microsecond
@@ -1944,26 +1946,49 @@
ie:
- 0) | up_write() {
- 0) 0.646 us | _spin_lock_irqsave();
- 0) 0.684 us | _spin_unlock_irqrestore();
- 0) 3.123 us | }
- 0) 0.548 us | fput();
- 0) + 58.628 us | }
+ 3) # 1837.709 us | } /* __switch_to */
+ 3) | finish_task_switch() {
+ 3) 0.313 us | _raw_spin_unlock_irq();
+ 3) 3.177 us | }
+ 3) # 1889.063 us | } /* __schedule */
+ 3) ! 140.417 us | } /* __schedule */
+ 3) # 2034.948 us | } /* schedule */
+ 3) * 33998.59 us | } /* schedule_preempt_disabled */
[...]
- 0) | putname() {
- 0) | kmem_cache_free() {
- 0) 0.518 us | __phys_addr();
- 0) 1.757 us | }
- 0) 2.861 us | }
- 0) ! 115.305 us | }
- 0) ! 116.402 us | }
+ 1) 0.260 us | msecs_to_jiffies();
+ 1) 0.313 us | __rcu_read_unlock();
+ 1) + 61.770 us | }
+ 1) + 64.479 us | }
+ 1) 0.313 us | rcu_bh_qs();
+ 1) 0.313 us | __local_bh_enable();
+ 1) ! 217.240 us | }
+ 1) 0.365 us | idle_cpu();
+ 1) | rcu_irq_exit() {
+ 1) 0.417 us | rcu_eqs_enter_common.isra.47();
+ 1) 3.125 us | }
+ 1) ! 227.812 us | }
+ 1) ! 457.395 us | }
+ 1) @ 119760.2 us | }
+
+ [...]
+
+ 2) | handle_IPI() {
+ 1) 6.979 us | }
+ 2) 0.417 us | scheduler_ipi();
+ 1) 9.791 us | }
+ 1) + 12.917 us | }
+ 2) 3.490 us | }
+ 1) + 15.729 us | }
+ 1) + 18.542 us | }
+ 2) $ 3594274 us | }
+ means that the function exceeded 10 usecs.
! means that the function exceeded 100 usecs.
# means that the function exceeded 1000 usecs.
+ * means that the function exceeded 10 msecs.
+ @ means that the function exceeded 100 msecs.
$ means that the function exceeded 1 sec.
diff --git a/arch/metag/include/asm/ftrace.h b/arch/metag/include/asm/ftrace.h
index 2901f0f..a2269d6 100644
--- a/arch/metag/include/asm/ftrace.h
+++ b/arch/metag/include/asm/ftrace.h
@@ -6,7 +6,7 @@
#ifndef __ASSEMBLY__
extern void mcount_wrapper(void);
-#define MCOUNT_ADDR ((long)(mcount_wrapper))
+#define MCOUNT_ADDR ((unsigned long)(mcount_wrapper))
static inline unsigned long ftrace_call_adjust(unsigned long addr)
{
diff --git a/arch/microblaze/include/asm/ftrace.h b/arch/microblaze/include/asm/ftrace.h
index fd2fa2ec..da0144f 100644
--- a/arch/microblaze/include/asm/ftrace.h
+++ b/arch/microblaze/include/asm/ftrace.h
@@ -3,7 +3,7 @@
#ifdef CONFIG_FUNCTION_TRACER
-#define MCOUNT_ADDR ((long)(_mcount))
+#define MCOUNT_ADDR ((unsigned long)(_mcount))
#define MCOUNT_INSN_SIZE 8 /* sizeof mcount call */
#ifndef __ASSEMBLY__
diff --git a/arch/powerpc/include/asm/ftrace.h b/arch/powerpc/include/asm/ftrace.h
index e366187..ef89b14 100644
--- a/arch/powerpc/include/asm/ftrace.h
+++ b/arch/powerpc/include/asm/ftrace.h
@@ -2,7 +2,7 @@
#define _ASM_POWERPC_FTRACE
#ifdef CONFIG_FUNCTION_TRACER
-#define MCOUNT_ADDR ((long)(_mcount))
+#define MCOUNT_ADDR ((unsigned long)(_mcount))
#define MCOUNT_INSN_SIZE 4 /* sizeof mcount call */
#ifdef __ASSEMBLY__
diff --git a/arch/sh/include/asm/ftrace.h b/arch/sh/include/asm/ftrace.h
index e79fb6e..1f157b8 100644
--- a/arch/sh/include/asm/ftrace.h
+++ b/arch/sh/include/asm/ftrace.h
@@ -9,7 +9,7 @@
#ifndef __ASSEMBLY__
extern void mcount(void);
-#define MCOUNT_ADDR ((long)(mcount))
+#define MCOUNT_ADDR ((unsigned long)(mcount))
#ifdef CONFIG_DYNAMIC_FTRACE
#define CALL_ADDR ((long)(ftrace_call))
diff --git a/arch/sparc/include/asm/ftrace.h b/arch/sparc/include/asm/ftrace.h
index 9ec94ad..3192a8e 100644
--- a/arch/sparc/include/asm/ftrace.h
+++ b/arch/sparc/include/asm/ftrace.h
@@ -2,7 +2,7 @@
#define _ASM_SPARC64_FTRACE
#ifdef CONFIG_MCOUNT
-#define MCOUNT_ADDR ((long)(_mcount))
+#define MCOUNT_ADDR ((unsigned long)(_mcount))
#define MCOUNT_INSN_SIZE 4 /* sizeof mcount call */
#ifndef __ASSEMBLY__
diff --git a/arch/x86/include/asm/ftrace.h b/arch/x86/include/asm/ftrace.h
index f45acad..2493885 100644
--- a/arch/x86/include/asm/ftrace.h
+++ b/arch/x86/include/asm/ftrace.h
@@ -3,9 +3,9 @@
#ifdef CONFIG_FUNCTION_TRACER
#ifdef CC_USING_FENTRY
-# define MCOUNT_ADDR ((long)(__fentry__))
+# define MCOUNT_ADDR ((unsigned long)(__fentry__))
#else
-# define MCOUNT_ADDR ((long)(mcount))
+# define MCOUNT_ADDR ((unsigned long)(mcount))
#endif
#define MCOUNT_INSN_SIZE 5 /* sizeof mcount call */
diff --git a/include/trace/events/task.h b/include/trace/events/task.h
index dee3bb1..2cca6cd 100644
--- a/include/trace/events/task.h
+++ b/include/trace/events/task.h
@@ -46,7 +46,7 @@
TP_fast_assign(
__entry->pid = task->pid;
memcpy(entry->oldcomm, task->comm, TASK_COMM_LEN);
- memcpy(entry->newcomm, comm, TASK_COMM_LEN);
+ strlcpy(entry->newcomm, comm, TASK_COMM_LEN);
__entry->oom_score_adj = task->signal->oom_score_adj;
),
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index eb11011..b0623ac 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -630,13 +630,18 @@
goto out;
}
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+ avg = rec->time;
+ do_div(avg, rec->counter);
+ if (tracing_thresh && (avg < tracing_thresh))
+ goto out;
+#endif
+
kallsyms_lookup(rec->ip, NULL, NULL, NULL, str);
seq_printf(m, " %-30.30s %10lu", str, rec->counter);
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
seq_puts(m, " ");
- avg = rec->time;
- do_div(avg, rec->counter);
/* Sample standard deviation (s^2) */
if (rec->counter <= 1)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 6260717..fc347f8 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -400,6 +400,17 @@
};
/*
+ * Structure to hold event state and handle nested events.
+ */
+struct rb_event_info {
+ u64 ts;
+ u64 delta;
+ unsigned long length;
+ struct buffer_page *tail_page;
+ int add_timestamp;
+};
+
+/*
* Used for which event context the event is in.
* NMI = 0
* IRQ = 1
@@ -1876,73 +1887,6 @@
return (addr & ~PAGE_MASK) - BUF_PAGE_HDR_SIZE;
}
-static inline int
-rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event)
-{
- unsigned long addr = (unsigned long)event;
- unsigned long index;
-
- index = rb_event_index(event);
- addr &= PAGE_MASK;
-
- return cpu_buffer->commit_page->page == (void *)addr &&
- rb_commit_index(cpu_buffer) == index;
-}
-
-static void
-rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
-{
- unsigned long max_count;
-
- /*
- * We only race with interrupts and NMIs on this CPU.
- * If we own the commit event, then we can commit
- * all others that interrupted us, since the interruptions
- * are in stack format (they finish before they come
- * back to us). This allows us to do a simple loop to
- * assign the commit to the tail.
- */
- again:
- max_count = cpu_buffer->nr_pages * 100;
-
- while (cpu_buffer->commit_page != cpu_buffer->tail_page) {
- if (RB_WARN_ON(cpu_buffer, !(--max_count)))
- return;
- if (RB_WARN_ON(cpu_buffer,
- rb_is_reader_page(cpu_buffer->tail_page)))
- return;
- local_set(&cpu_buffer->commit_page->page->commit,
- rb_page_write(cpu_buffer->commit_page));
- rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
- cpu_buffer->write_stamp =
- cpu_buffer->commit_page->page->time_stamp;
- /* add barrier to keep gcc from optimizing too much */
- barrier();
- }
- while (rb_commit_index(cpu_buffer) !=
- rb_page_write(cpu_buffer->commit_page)) {
-
- local_set(&cpu_buffer->commit_page->page->commit,
- rb_page_write(cpu_buffer->commit_page));
- RB_WARN_ON(cpu_buffer,
- local_read(&cpu_buffer->commit_page->page->commit) &
- ~RB_WRITE_MASK);
- barrier();
- }
-
- /* again, keep gcc from optimizing */
- barrier();
-
- /*
- * If an interrupt came in just after the first while loop
- * and pushed the tail page forward, we will be left with
- * a dangling commit that will never go forward.
- */
- if (unlikely(cpu_buffer->commit_page != cpu_buffer->tail_page))
- goto again;
-}
-
static void rb_reset_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
{
cpu_buffer->read_stamp = cpu_buffer->reader_page->page->time_stamp;
@@ -1968,64 +1912,6 @@
iter->head = 0;
}
-/* Slow path, do not inline */
-static noinline struct ring_buffer_event *
-rb_add_time_stamp(struct ring_buffer_event *event, u64 delta)
-{
- event->type_len = RINGBUF_TYPE_TIME_EXTEND;
-
- /* Not the first event on the page? */
- if (rb_event_index(event)) {
- event->time_delta = delta & TS_MASK;
- event->array[0] = delta >> TS_SHIFT;
- } else {
- /* nope, just zero it */
- event->time_delta = 0;
- event->array[0] = 0;
- }
-
- return skip_time_extend(event);
-}
-
-/**
- * rb_update_event - update event type and data
- * @event: the event to update
- * @type: the type of event
- * @length: the size of the event field in the ring buffer
- *
- * Update the type and data fields of the event. The length
- * is the actual size that is written to the ring buffer,
- * and with this, we can determine what to place into the
- * data field.
- */
-static void
-rb_update_event(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event, unsigned length,
- int add_timestamp, u64 delta)
-{
- /* Only a commit updates the timestamp */
- if (unlikely(!rb_event_is_commit(cpu_buffer, event)))
- delta = 0;
-
- /*
- * If we need to add a timestamp, then we
- * add it to the start of the resevered space.
- */
- if (unlikely(add_timestamp)) {
- event = rb_add_time_stamp(event, delta);
- length -= RB_LEN_TIME_EXTEND;
- delta = 0;
- }
-
- event->time_delta = delta;
- length -= RB_EVNT_HDR_SIZE;
- if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT) {
- event->type_len = 0;
- event->array[0] = length;
- } else
- event->type_len = DIV_ROUND_UP(length, RB_ALIGNMENT);
-}
-
/*
* rb_handle_head_page - writer hit the head page
*
@@ -2184,29 +2070,13 @@
return 0;
}
-static unsigned rb_calculate_event_length(unsigned length)
-{
- struct ring_buffer_event event; /* Used only for sizeof array */
-
- /* zero length can cause confusions */
- if (!length)
- length++;
-
- if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT)
- length += sizeof(event.array[0]);
-
- length += RB_EVNT_HDR_SIZE;
- length = ALIGN(length, RB_ARCH_ALIGNMENT);
-
- return length;
-}
-
static inline void
rb_reset_tail(struct ring_buffer_per_cpu *cpu_buffer,
- struct buffer_page *tail_page,
- unsigned long tail, unsigned long length)
+ unsigned long tail, struct rb_event_info *info)
{
+ struct buffer_page *tail_page = info->tail_page;
struct ring_buffer_event *event;
+ unsigned long length = info->length;
/*
* Only the event that crossed the page boundary
@@ -2276,13 +2146,14 @@
*/
static noinline struct ring_buffer_event *
rb_move_tail(struct ring_buffer_per_cpu *cpu_buffer,
- unsigned long length, unsigned long tail,
- struct buffer_page *tail_page, u64 ts)
+ unsigned long tail, struct rb_event_info *info)
{
+ struct buffer_page *tail_page = info->tail_page;
struct buffer_page *commit_page = cpu_buffer->commit_page;
struct ring_buffer *buffer = cpu_buffer->buffer;
struct buffer_page *next_page;
int ret;
+ u64 ts;
next_page = tail_page;
@@ -2368,75 +2239,121 @@
out_again:
- rb_reset_tail(cpu_buffer, tail_page, tail, length);
+ rb_reset_tail(cpu_buffer, tail, info);
/* fail and let the caller try again */
return ERR_PTR(-EAGAIN);
out_reset:
/* reset write */
- rb_reset_tail(cpu_buffer, tail_page, tail, length);
+ rb_reset_tail(cpu_buffer, tail, info);
return NULL;
}
-static struct ring_buffer_event *
-__rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
- unsigned long length, u64 ts,
- u64 delta, int add_timestamp)
+/* Slow path, do not inline */
+static noinline struct ring_buffer_event *
+rb_add_time_stamp(struct ring_buffer_event *event, u64 delta)
{
- struct buffer_page *tail_page;
- struct ring_buffer_event *event;
- unsigned long tail, write;
+ event->type_len = RINGBUF_TYPE_TIME_EXTEND;
- /*
- * If the time delta since the last event is too big to
- * hold in the time field of the event, then we append a
- * TIME EXTEND event ahead of the data event.
- */
- if (unlikely(add_timestamp))
- length += RB_LEN_TIME_EXTEND;
+ /* Not the first event on the page? */
+ if (rb_event_index(event)) {
+ event->time_delta = delta & TS_MASK;
+ event->array[0] = delta >> TS_SHIFT;
+ } else {
+ /* nope, just zero it */
+ event->time_delta = 0;
+ event->array[0] = 0;
+ }
- tail_page = cpu_buffer->tail_page;
- write = local_add_return(length, &tail_page->write);
+ return skip_time_extend(event);
+}
- /* set write to only the index of the write */
- write &= RB_WRITE_MASK;
- tail = write - length;
+static inline int rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event);
- /*
- * If this is the first commit on the page, then it has the same
- * timestamp as the page itself.
- */
- if (!tail)
+/**
+ * rb_update_event - update event type and data
+ * @event: the event to update
+ * @type: the type of event
+ * @length: the size of the event field in the ring buffer
+ *
+ * Update the type and data fields of the event. The length
+ * is the actual size that is written to the ring buffer,
+ * and with this, we can determine what to place into the
+ * data field.
+ */
+static void
+rb_update_event(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event,
+ struct rb_event_info *info)
+{
+ unsigned length = info->length;
+ u64 delta = info->delta;
+
+ /* Only a commit updates the timestamp */
+ if (unlikely(!rb_event_is_commit(cpu_buffer, event)))
delta = 0;
- /* See if we shot pass the end of this buffer page */
- if (unlikely(write > BUF_PAGE_SIZE))
- return rb_move_tail(cpu_buffer, length, tail,
- tail_page, ts);
+ /*
+ * If we need to add a timestamp, then we
+ * add it to the start of the resevered space.
+ */
+ if (unlikely(info->add_timestamp)) {
+ event = rb_add_time_stamp(event, delta);
+ length -= RB_LEN_TIME_EXTEND;
+ delta = 0;
+ }
- /* We reserved something on the buffer */
+ event->time_delta = delta;
+ length -= RB_EVNT_HDR_SIZE;
+ if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT) {
+ event->type_len = 0;
+ event->array[0] = length;
+ } else
+ event->type_len = DIV_ROUND_UP(length, RB_ALIGNMENT);
+}
- event = __rb_page_index(tail_page, tail);
- kmemcheck_annotate_bitfield(event, bitfield);
- rb_update_event(cpu_buffer, event, length, add_timestamp, delta);
+static unsigned rb_calculate_event_length(unsigned length)
+{
+ struct ring_buffer_event event; /* Used only for sizeof array */
- local_inc(&tail_page->entries);
+ /* zero length can cause confusions */
+ if (!length)
+ length++;
+
+ if (length > RB_MAX_SMALL_DATA || RB_FORCE_8BYTE_ALIGNMENT)
+ length += sizeof(event.array[0]);
+
+ length += RB_EVNT_HDR_SIZE;
+ length = ALIGN(length, RB_ARCH_ALIGNMENT);
/*
- * If this is the first commit on the page, then update
- * its timestamp.
+ * In case the time delta is larger than the 27 bits for it
+ * in the header, we need to add a timestamp. If another
+ * event comes in when trying to discard this one to increase
+ * the length, then the timestamp will be added in the allocated
+ * space of this event. If length is bigger than the size needed
+ * for the TIME_EXTEND, then padding has to be used. The events
+ * length must be either RB_LEN_TIME_EXTEND, or greater than or equal
+ * to RB_LEN_TIME_EXTEND + 8, as 8 is the minimum size for padding.
+ * As length is a multiple of 4, we only need to worry if it
+ * is 12 (RB_LEN_TIME_EXTEND + 4).
*/
- if (!tail)
- tail_page->page->time_stamp = ts;
+ if (length == RB_LEN_TIME_EXTEND + RB_ALIGNMENT)
+ length += RB_ALIGNMENT;
- /* account for these added bytes */
- local_add(length, &cpu_buffer->entries_bytes);
-
- return event;
+ return length;
}
+#ifndef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
+static inline bool sched_clock_stable(void)
+{
+ return true;
+}
+#endif
+
static inline int
rb_try_to_discard(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
@@ -2483,6 +2400,59 @@
local_inc(&cpu_buffer->commits);
}
+static void
+rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
+{
+ unsigned long max_count;
+
+ /*
+ * We only race with interrupts and NMIs on this CPU.
+ * If we own the commit event, then we can commit
+ * all others that interrupted us, since the interruptions
+ * are in stack format (they finish before they come
+ * back to us). This allows us to do a simple loop to
+ * assign the commit to the tail.
+ */
+ again:
+ max_count = cpu_buffer->nr_pages * 100;
+
+ while (cpu_buffer->commit_page != cpu_buffer->tail_page) {
+ if (RB_WARN_ON(cpu_buffer, !(--max_count)))
+ return;
+ if (RB_WARN_ON(cpu_buffer,
+ rb_is_reader_page(cpu_buffer->tail_page)))
+ return;
+ local_set(&cpu_buffer->commit_page->page->commit,
+ rb_page_write(cpu_buffer->commit_page));
+ rb_inc_page(cpu_buffer, &cpu_buffer->commit_page);
+ cpu_buffer->write_stamp =
+ cpu_buffer->commit_page->page->time_stamp;
+ /* add barrier to keep gcc from optimizing too much */
+ barrier();
+ }
+ while (rb_commit_index(cpu_buffer) !=
+ rb_page_write(cpu_buffer->commit_page)) {
+
+ local_set(&cpu_buffer->commit_page->page->commit,
+ rb_page_write(cpu_buffer->commit_page));
+ RB_WARN_ON(cpu_buffer,
+ local_read(&cpu_buffer->commit_page->page->commit) &
+ ~RB_WRITE_MASK);
+ barrier();
+ }
+
+ /* again, keep gcc from optimizing */
+ barrier();
+
+ /*
+ * If an interrupt came in just after the first while loop
+ * and pushed the tail page forward, we will be left with
+ * a dangling commit that will never go forward.
+ */
+ if (unlikely(cpu_buffer->commit_page != cpu_buffer->tail_page))
+ goto again;
+}
+
static inline void rb_end_commit(struct ring_buffer_per_cpu *cpu_buffer)
{
unsigned long commits;
@@ -2515,91 +2485,94 @@
}
}
-static struct ring_buffer_event *
-rb_reserve_next_event(struct ring_buffer *buffer,
- struct ring_buffer_per_cpu *cpu_buffer,
- unsigned long length)
+static inline void rb_event_discard(struct ring_buffer_event *event)
{
- struct ring_buffer_event *event;
- u64 ts, delta;
- int nr_loops = 0;
- int add_timestamp;
- u64 diff;
+ if (event->type_len == RINGBUF_TYPE_TIME_EXTEND)
+ event = skip_time_extend(event);
- rb_start_commit(cpu_buffer);
+ /* array[0] holds the actual length for the discarded event */
+ event->array[0] = rb_event_data_length(event) - RB_EVNT_HDR_SIZE;
+ event->type_len = RINGBUF_TYPE_PADDING;
+ /* time delta must be non zero */
+ if (!event->time_delta)
+ event->time_delta = 1;
+}
-#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
- /*
- * Due to the ability to swap a cpu buffer from a buffer
- * it is possible it was swapped before we committed.
- * (committing stops a swap). We check for it here and
- * if it happened, we have to fail the write.
- */
- barrier();
- if (unlikely(ACCESS_ONCE(cpu_buffer->buffer) != buffer)) {
- local_dec(&cpu_buffer->committing);
- local_dec(&cpu_buffer->commits);
- return NULL;
- }
-#endif
+static inline int
+rb_event_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
+{
+ unsigned long addr = (unsigned long)event;
+ unsigned long index;
- length = rb_calculate_event_length(length);
- again:
- add_timestamp = 0;
- delta = 0;
+ index = rb_event_index(event);
+ addr &= PAGE_MASK;
+
+ return cpu_buffer->commit_page->page == (void *)addr &&
+ rb_commit_index(cpu_buffer) == index;
+}
+
+static void
+rb_update_write_stamp(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
+{
+ u64 delta;
/*
- * We allow for interrupts to reenter here and do a trace.
- * If one does, it will cause this original code to loop
- * back here. Even with heavy interrupts happening, this
- * should only happen a few times in a row. If this happens
- * 1000 times in a row, there must be either an interrupt
- * storm or we have something buggy.
- * Bail!
+ * The event first in the commit queue updates the
+ * time stamp.
*/
- if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000))
- goto out_fail;
-
- ts = rb_time_stamp(cpu_buffer->buffer);
- diff = ts - cpu_buffer->write_stamp;
-
- /* make sure this diff is calculated here */
- barrier();
-
- /* Did the write stamp get updated already? */
- if (likely(ts >= cpu_buffer->write_stamp)) {
- delta = diff;
- if (unlikely(test_time_stamp(delta))) {
- int local_clock_stable = 1;
-#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
- local_clock_stable = sched_clock_stable();
-#endif
- WARN_ONCE(delta > (1ULL << 59),
- KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s",
- (unsigned long long)delta,
- (unsigned long long)ts,
- (unsigned long long)cpu_buffer->write_stamp,
- local_clock_stable ? "" :
- "If you just came from a suspend/resume,\n"
- "please switch to the trace global clock:\n"
- " echo global > /sys/kernel/debug/tracing/trace_clock\n");
- add_timestamp = 1;
- }
+ if (rb_event_is_commit(cpu_buffer, event)) {
+ /*
+ * A commit event that is first on a page
+ * updates the write timestamp with the page stamp
+ */
+ if (!rb_event_index(event))
+ cpu_buffer->write_stamp =
+ cpu_buffer->commit_page->page->time_stamp;
+ else if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) {
+ delta = event->array[0];
+ delta <<= TS_SHIFT;
+ delta += event->time_delta;
+ cpu_buffer->write_stamp += delta;
+ } else
+ cpu_buffer->write_stamp += event->time_delta;
}
+}
- event = __rb_reserve_next(cpu_buffer, length, ts,
- delta, add_timestamp);
- if (unlikely(PTR_ERR(event) == -EAGAIN))
- goto again;
-
- if (!event)
- goto out_fail;
-
- return event;
-
- out_fail:
+static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
+ struct ring_buffer_event *event)
+{
+ local_inc(&cpu_buffer->entries);
+ rb_update_write_stamp(cpu_buffer, event);
rb_end_commit(cpu_buffer);
- return NULL;
+}
+
+static __always_inline void
+rb_wakeups(struct ring_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer)
+{
+ bool pagebusy;
+
+ if (buffer->irq_work.waiters_pending) {
+ buffer->irq_work.waiters_pending = false;
+ /* irq_work_queue() supplies it's own memory barriers */
+ irq_work_queue(&buffer->irq_work.work);
+ }
+
+ if (cpu_buffer->irq_work.waiters_pending) {
+ cpu_buffer->irq_work.waiters_pending = false;
+ /* irq_work_queue() supplies it's own memory barriers */
+ irq_work_queue(&cpu_buffer->irq_work.work);
+ }
+
+ pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page;
+
+ if (!pagebusy && cpu_buffer->irq_work.full_waiters_pending) {
+ cpu_buffer->irq_work.wakeup_full = true;
+ cpu_buffer->irq_work.full_waiters_pending = false;
+ /* irq_work_queue() supplies it's own memory barriers */
+ irq_work_queue(&cpu_buffer->irq_work.work);
+ }
}
/*
@@ -2672,6 +2645,178 @@
}
/**
+ * ring_buffer_unlock_commit - commit a reserved
+ * @buffer: The buffer to commit to
+ * @event: The event pointer to commit.
+ *
+ * This commits the data to the ring buffer, and releases any locks held.
+ *
+ * Must be paired with ring_buffer_lock_reserve.
+ */
+int ring_buffer_unlock_commit(struct ring_buffer *buffer,
+ struct ring_buffer_event *event)
+{
+ struct ring_buffer_per_cpu *cpu_buffer;
+ int cpu = raw_smp_processor_id();
+
+ cpu_buffer = buffer->buffers[cpu];
+
+ rb_commit(cpu_buffer, event);
+
+ rb_wakeups(buffer, cpu_buffer);
+
+ trace_recursive_unlock(cpu_buffer);
+
+ preempt_enable_notrace();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit);
+
+static noinline void
+rb_handle_timestamp(struct ring_buffer_per_cpu *cpu_buffer,
+ struct rb_event_info *info)
+{
+ WARN_ONCE(info->delta > (1ULL << 59),
+ KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s",
+ (unsigned long long)info->delta,
+ (unsigned long long)info->ts,
+ (unsigned long long)cpu_buffer->write_stamp,
+ sched_clock_stable() ? "" :
+ "If you just came from a suspend/resume,\n"
+ "please switch to the trace global clock:\n"
+ " echo global > /sys/kernel/debug/tracing/trace_clock\n");
+ info->add_timestamp = 1;
+}
+
+static struct ring_buffer_event *
+__rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
+ struct rb_event_info *info)
+{
+ struct ring_buffer_event *event;
+ struct buffer_page *tail_page;
+ unsigned long tail, write;
+
+ /*
+ * If the time delta since the last event is too big to
+ * hold in the time field of the event, then we append a
+ * TIME EXTEND event ahead of the data event.
+ */
+ if (unlikely(info->add_timestamp))
+ info->length += RB_LEN_TIME_EXTEND;
+
+ tail_page = info->tail_page = cpu_buffer->tail_page;
+ write = local_add_return(info->length, &tail_page->write);
+
+ /* set write to only the index of the write */
+ write &= RB_WRITE_MASK;
+ tail = write - info->length;
+
+ /*
+ * If this is the first commit on the page, then it has the same
+ * timestamp as the page itself.
+ */
+ if (!tail)
+ info->delta = 0;
+
+ /* See if we shot pass the end of this buffer page */
+ if (unlikely(write > BUF_PAGE_SIZE))
+ return rb_move_tail(cpu_buffer, tail, info);
+
+ /* We reserved something on the buffer */
+
+ event = __rb_page_index(tail_page, tail);
+ kmemcheck_annotate_bitfield(event, bitfield);
+ rb_update_event(cpu_buffer, event, info);
+
+ local_inc(&tail_page->entries);
+
+ /*
+ * If this is the first commit on the page, then update
+ * its timestamp.
+ */
+ if (!tail)
+ tail_page->page->time_stamp = info->ts;
+
+ /* account for these added bytes */
+ local_add(info->length, &cpu_buffer->entries_bytes);
+
+ return event;
+}
+
+static struct ring_buffer_event *
+rb_reserve_next_event(struct ring_buffer *buffer,
+ struct ring_buffer_per_cpu *cpu_buffer,
+ unsigned long length)
+{
+ struct ring_buffer_event *event;
+ struct rb_event_info info;
+ int nr_loops = 0;
+ u64 diff;
+
+ rb_start_commit(cpu_buffer);
+
+#ifdef CONFIG_RING_BUFFER_ALLOW_SWAP
+ /*
+ * Due to the ability to swap a cpu buffer from a buffer
+ * it is possible it was swapped before we committed.
+ * (committing stops a swap). We check for it here and
+ * if it happened, we have to fail the write.
+ */
+ barrier();
+ if (unlikely(ACCESS_ONCE(cpu_buffer->buffer) != buffer)) {
+ local_dec(&cpu_buffer->committing);
+ local_dec(&cpu_buffer->commits);
+ return NULL;
+ }
+#endif
+
+ info.length = rb_calculate_event_length(length);
+ again:
+ info.add_timestamp = 0;
+ info.delta = 0;
+
+ /*
+ * We allow for interrupts to reenter here and do a trace.
+ * If one does, it will cause this original code to loop
+ * back here. Even with heavy interrupts happening, this
+ * should only happen a few times in a row. If this happens
+ * 1000 times in a row, there must be either an interrupt
+ * storm or we have something buggy.
+ * Bail!
+ */
+ if (RB_WARN_ON(cpu_buffer, ++nr_loops > 1000))
+ goto out_fail;
+
+ info.ts = rb_time_stamp(cpu_buffer->buffer);
+ diff = info.ts - cpu_buffer->write_stamp;
+
+ /* make sure this diff is calculated here */
+ barrier();
+
+ /* Did the write stamp get updated already? */
+ if (likely(info.ts >= cpu_buffer->write_stamp)) {
+ info.delta = diff;
+ if (unlikely(test_time_stamp(info.delta)))
+ rb_handle_timestamp(cpu_buffer, &info);
+ }
+
+ event = __rb_reserve_next(cpu_buffer, &info);
+
+ if (unlikely(PTR_ERR(event) == -EAGAIN))
+ goto again;
+
+ if (!event)
+ goto out_fail;
+
+ return event;
+
+ out_fail:
+ rb_end_commit(cpu_buffer);
+ return NULL;
+}
+
+/**
* ring_buffer_lock_reserve - reserve a part of the buffer
* @buffer: the ring buffer to reserve from
* @length: the length of the data to reserve (excluding event header)
@@ -2729,111 +2874,6 @@
}
EXPORT_SYMBOL_GPL(ring_buffer_lock_reserve);
-static void
-rb_update_write_stamp(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event)
-{
- u64 delta;
-
- /*
- * The event first in the commit queue updates the
- * time stamp.
- */
- if (rb_event_is_commit(cpu_buffer, event)) {
- /*
- * A commit event that is first on a page
- * updates the write timestamp with the page stamp
- */
- if (!rb_event_index(event))
- cpu_buffer->write_stamp =
- cpu_buffer->commit_page->page->time_stamp;
- else if (event->type_len == RINGBUF_TYPE_TIME_EXTEND) {
- delta = event->array[0];
- delta <<= TS_SHIFT;
- delta += event->time_delta;
- cpu_buffer->write_stamp += delta;
- } else
- cpu_buffer->write_stamp += event->time_delta;
- }
-}
-
-static void rb_commit(struct ring_buffer_per_cpu *cpu_buffer,
- struct ring_buffer_event *event)
-{
- local_inc(&cpu_buffer->entries);
- rb_update_write_stamp(cpu_buffer, event);
- rb_end_commit(cpu_buffer);
-}
-
-static __always_inline void
-rb_wakeups(struct ring_buffer *buffer, struct ring_buffer_per_cpu *cpu_buffer)
-{
- bool pagebusy;
-
- if (buffer->irq_work.waiters_pending) {
- buffer->irq_work.waiters_pending = false;
- /* irq_work_queue() supplies it's own memory barriers */
- irq_work_queue(&buffer->irq_work.work);
- }
-
- if (cpu_buffer->irq_work.waiters_pending) {
- cpu_buffer->irq_work.waiters_pending = false;
- /* irq_work_queue() supplies it's own memory barriers */
- irq_work_queue(&cpu_buffer->irq_work.work);
- }
-
- pagebusy = cpu_buffer->reader_page == cpu_buffer->commit_page;
-
- if (!pagebusy && cpu_buffer->irq_work.full_waiters_pending) {
- cpu_buffer->irq_work.wakeup_full = true;
- cpu_buffer->irq_work.full_waiters_pending = false;
- /* irq_work_queue() supplies it's own memory barriers */
- irq_work_queue(&cpu_buffer->irq_work.work);
- }
-}
-
-/**
- * ring_buffer_unlock_commit - commit a reserved
- * @buffer: The buffer to commit to
- * @event: The event pointer to commit.
- *
- * This commits the data to the ring buffer, and releases any locks held.
- *
- * Must be paired with ring_buffer_lock_reserve.
- */
-int ring_buffer_unlock_commit(struct ring_buffer *buffer,
- struct ring_buffer_event *event)
-{
- struct ring_buffer_per_cpu *cpu_buffer;
- int cpu = raw_smp_processor_id();
-
- cpu_buffer = buffer->buffers[cpu];
-
- rb_commit(cpu_buffer, event);
-
- rb_wakeups(buffer, cpu_buffer);
-
- trace_recursive_unlock(cpu_buffer);
-
- preempt_enable_notrace();
-
- return 0;
-}
-EXPORT_SYMBOL_GPL(ring_buffer_unlock_commit);
-
-static inline void rb_event_discard(struct ring_buffer_event *event)
-{
- if (event->type_len == RINGBUF_TYPE_TIME_EXTEND)
- event = skip_time_extend(event);
-
- /* array[0] holds the actual length for the discarded event */
- event->array[0] = rb_event_data_length(event) - RB_EVNT_HDR_SIZE;
- event->type_len = RINGBUF_TYPE_PADDING;
- /* time delta must be non zero */
- if (!event->time_delta)
- event->time_delta = 1;
-}
-
/*
* Decrement the entries to the page that an event is on.
* The event does not even need to exist, only the pointer
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index abcbf7f..6e79408 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3035,7 +3035,7 @@
if (!iter)
return ERR_PTR(-ENOMEM);
- iter->buffer_iter = kzalloc(sizeof(*iter->buffer_iter) * num_possible_cpus(),
+ iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter),
GFP_KERNEL);
if (!iter->buffer_iter)
goto release;
@@ -6990,7 +6990,7 @@
trace_init_global_iter(&iter);
for_each_tracing_cpu(cpu) {
- atomic_inc(&per_cpu_ptr(iter.tr->trace_buffer.data, cpu)->disabled);
+ atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled);
}
old_userobj = trace_flags & TRACE_ITER_SYM_USEROBJ;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 404a372..7ca09cd 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -30,6 +30,7 @@
DEFINE_MUTEX(event_mutex);
LIST_HEAD(ftrace_events);
+static LIST_HEAD(ftrace_generic_fields);
static LIST_HEAD(ftrace_common_fields);
#define GFP_TRACE (GFP_KERNEL | __GFP_ZERO)
@@ -94,6 +95,10 @@
struct ftrace_event_field *field;
struct list_head *head;
+ field = __find_event_field(&ftrace_generic_fields, name);
+ if (field)
+ return field;
+
field = __find_event_field(&ftrace_common_fields, name);
if (field)
return field;
@@ -144,6 +149,13 @@
}
EXPORT_SYMBOL_GPL(trace_define_field);
+#define __generic_field(type, item, filter_type) \
+ ret = __trace_define_field(&ftrace_generic_fields, #type, \
+ #item, 0, 0, is_signed_type(type), \
+ filter_type); \
+ if (ret) \
+ return ret;
+
#define __common_field(type, item) \
ret = __trace_define_field(&ftrace_common_fields, #type, \
"common_" #item, \
@@ -153,6 +165,16 @@
if (ret) \
return ret;
+static int trace_define_generic_fields(void)
+{
+ int ret;
+
+ __generic_field(int, cpu, FILTER_OTHER);
+ __generic_field(char *, comm, FILTER_PTR_STRING);
+
+ return ret;
+}
+
static int trace_define_common_fields(void)
{
int ret;
@@ -2671,6 +2693,9 @@
if (!entry)
pr_warn("Could not create tracefs 'available_events' entry\n");
+ if (trace_define_generic_fields())
+ pr_warn("tracing: Failed to allocated generic fields");
+
if (trace_define_common_fields())
pr_warn("tracing: Failed to allocate common fields");
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index d81d6f3..bd1bf18 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -252,6 +252,50 @@
return match;
}
+/* Filter predicate for CPUs. */
+static int filter_pred_cpu(struct filter_pred *pred, void *event)
+{
+ int cpu, cmp;
+ int match = 0;
+
+ cpu = raw_smp_processor_id();
+ cmp = pred->val;
+
+ switch (pred->op) {
+ case OP_EQ:
+ match = cpu == cmp;
+ break;
+ case OP_LT:
+ match = cpu < cmp;
+ break;
+ case OP_LE:
+ match = cpu <= cmp;
+ break;
+ case OP_GT:
+ match = cpu > cmp;
+ break;
+ case OP_GE:
+ match = cpu >= cmp;
+ break;
+ default:
+ break;
+ }
+
+ return !!match == !pred->not;
+}
+
+/* Filter predicate for COMM. */
+static int filter_pred_comm(struct filter_pred *pred, void *event)
+{
+ int cmp, match;
+
+ cmp = pred->regex.match(current->comm, &pred->regex,
+ pred->regex.field_len);
+ match = cmp ^ pred->not;
+
+ return match;
+}
+
static int filter_pred_none(struct filter_pred *pred, void *event)
{
return 0;
@@ -1002,7 +1046,10 @@
if (is_string_field(field)) {
filter_build_regex(pred);
- if (field->filter_type == FILTER_STATIC_STRING) {
+ if (!strcmp(field->name, "comm")) {
+ fn = filter_pred_comm;
+ pred->regex.field_len = TASK_COMM_LEN;
+ } else if (field->filter_type == FILTER_STATIC_STRING) {
fn = filter_pred_string;
pred->regex.field_len = field->size;
} else if (field->filter_type == FILTER_DYN_STRING)
@@ -1025,7 +1072,10 @@
}
pred->val = val;
- fn = select_comparison_fn(pred->op, field->size,
+ if (!strcmp(field->name, "cpu"))
+ fn = filter_pred_cpu;
+ else
+ fn = select_comparison_fn(pred->op, field->size,
field->is_signed);
if (!fn) {
parse_error(ps, FILT_ERR_INVALID_OP, 0);
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 8968bf7..ca98445 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -715,13 +715,13 @@
snprintf(nsecs_str, slen, "%03lu", nsecs_rem);
trace_seq_printf(s, ".%s", nsecs_str);
- len += strlen(nsecs_str);
+ len += strlen(nsecs_str) + 1;
}
trace_seq_puts(s, " us ");
/* Print remaining spaces to fit the row's width */
- for (i = len; i < 7; i++)
+ for (i = len; i < 8; i++)
trace_seq_putc(s, ' ');
}
diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c
index dfab253..8e481a8 100644
--- a/kernel/trace/trace_output.c
+++ b/kernel/trace/trace_output.c
@@ -496,6 +496,8 @@
char sym;
} mark[] = {
MARK(1000000000ULL , '$'), /* 1 sec */
+ MARK(100000000ULL , '@'), /* 100 msec */
+ MARK(10000000ULL , '*'), /* 10 msec */
MARK(1000000ULL , '#'), /* 1000 usecs */
MARK(100000ULL , '!'), /* 100 usecs */
MARK(10000ULL , '+'), /* 10 usecs */
@@ -508,7 +510,7 @@
int size = ARRAY_SIZE(mark);
for (i = 0; i < size; i++) {
- if (d >= mark[i].val)
+ if (d > mark[i].val)
break;
}
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index 3f34496..b746399 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -18,12 +18,6 @@
#define STACK_TRACE_ENTRIES 500
-#ifdef CC_USING_FENTRY
-# define fentry 1
-#else
-# define fentry 0
-#endif
-
static unsigned long stack_dump_trace[STACK_TRACE_ENTRIES+1] =
{ [0 ... (STACK_TRACE_ENTRIES)] = ULONG_MAX };
static unsigned stack_dump_index[STACK_TRACE_ENTRIES];
@@ -35,7 +29,7 @@
*/
static struct stack_trace max_stack_trace = {
.max_entries = STACK_TRACE_ENTRIES - 1,
- .entries = &stack_dump_trace[1],
+ .entries = &stack_dump_trace[0],
};
static unsigned long max_stack_size;
@@ -55,7 +49,7 @@
pr_emerg(" Depth Size Location (%d entries)\n"
" ----- ---- --------\n",
- max_stack_trace.nr_entries - 1);
+ max_stack_trace.nr_entries);
for (i = 0; i < max_stack_trace.nr_entries; i++) {
if (stack_dump_trace[i] == ULONG_MAX)
@@ -77,7 +71,7 @@
unsigned long this_size, flags; unsigned long *p, *top, *start;
static int tracer_frame;
int frame_size = ACCESS_ONCE(tracer_frame);
- int i;
+ int i, x;
this_size = ((unsigned long)stack) & (THREAD_SIZE-1);
this_size = THREAD_SIZE - this_size;
@@ -105,26 +99,20 @@
max_stack_size = this_size;
max_stack_trace.nr_entries = 0;
-
- if (using_ftrace_ops_list_func())
- max_stack_trace.skip = 4;
- else
- max_stack_trace.skip = 3;
+ max_stack_trace.skip = 3;
save_stack_trace(&max_stack_trace);
- /*
- * Add the passed in ip from the function tracer.
- * Searching for this on the stack will skip over
- * most of the overhead from the stack tracer itself.
- */
- stack_dump_trace[0] = ip;
- max_stack_trace.nr_entries++;
+ /* Skip over the overhead of the stack tracer itself */
+ for (i = 0; i < max_stack_trace.nr_entries; i++) {
+ if (stack_dump_trace[i] == ip)
+ break;
+ }
/*
* Now find where in the stack these are.
*/
- i = 0;
+ x = 0;
start = stack;
top = (unsigned long *)
(((unsigned long)start & ~(THREAD_SIZE-1)) + THREAD_SIZE);
@@ -139,12 +127,15 @@
while (i < max_stack_trace.nr_entries) {
int found = 0;
- stack_dump_index[i] = this_size;
+ stack_dump_index[x] = this_size;
p = start;
for (; p < top && i < max_stack_trace.nr_entries; p++) {
+ if (stack_dump_trace[i] == ULONG_MAX)
+ break;
if (*p == stack_dump_trace[i]) {
- this_size = stack_dump_index[i++] =
+ stack_dump_trace[x] = stack_dump_trace[i++];
+ this_size = stack_dump_index[x++] =
(top - p) * sizeof(unsigned long);
found = 1;
/* Start the search from here */
@@ -156,7 +147,7 @@
* out what that is, then figure it out
* now.
*/
- if (unlikely(!tracer_frame) && i == 1) {
+ if (unlikely(!tracer_frame)) {
tracer_frame = (p - stack) *
sizeof(unsigned long);
max_stack_size -= tracer_frame;
@@ -168,6 +159,10 @@
i++;
}
+ max_stack_trace.nr_entries = x;
+ for (; x < i; x++)
+ stack_dump_trace[x] = ULONG_MAX;
+
if (task_stack_end_corrupted(current)) {
print_max_stack();
BUG();
@@ -192,24 +187,7 @@
if (per_cpu(trace_active, cpu)++ != 0)
goto out;
- /*
- * When fentry is used, the traced function does not get
- * its stack frame set up, and we lose the parent.
- * The ip is pretty useless because the function tracer
- * was called before that function set up its stack frame.
- * In this case, we use the parent ip.
- *
- * By adding the return address of either the parent ip
- * or the current ip we can disregard most of the stack usage
- * caused by the stack tracer itself.
- *
- * The function tracer always reports the address of where the
- * mcount call was, but the stack will hold the return address.
- */
- if (fentry)
- ip = parent_ip;
- else
- ip += MCOUNT_INSN_SIZE;
+ ip += MCOUNT_INSN_SIZE;
check_stack(ip, &stack);
@@ -284,7 +262,7 @@
{
long n = *pos - 1;
- if (n >= max_stack_trace.nr_entries || stack_dump_trace[n] == ULONG_MAX)
+ if (n > max_stack_trace.nr_entries || stack_dump_trace[n] == ULONG_MAX)
return NULL;
m->private = (void *)n;
@@ -354,7 +332,7 @@
seq_printf(m, " Depth Size Location"
" (%d entries)\n"
" ----- ---- --------\n",
- max_stack_trace.nr_entries - 1);
+ max_stack_trace.nr_entries);
if (!stack_tracer_enabled && !max_stack_size)
print_disabled(m);