Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 911 insertions, 0 deletions

diff --git a/tools/perf/util/intel-bts.c b/tools/perf/util/intel-bts.c
new file mode 100644
index 000000000..02df3e460
--- /dev/null
+++ b/tools/perf/util/intel-bts.c
@@ -0,0 +1,911 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * intel-bts.c: Intel Processor Trace support
+ * Copyright (c) 2013-2015, Intel Corporation.
+ */
+
+#include <endian.h>
+#include <errno.h>
+#include <byteswap.h>
+#include <inttypes.h>
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/log2.h>
+#include <linux/zalloc.h>
+
+#include "color.h"
+#include "evsel.h"
+#include "evlist.h"
+#include "machine.h"
+#include "symbol.h"
+#include "session.h"
+#include "tool.h"
+#include "thread.h"
+#include "thread-stack.h"
+#include "debug.h"
+#include "tsc.h"
+#include "auxtrace.h"
+#include "intel-pt-decoder/intel-pt-insn-decoder.h"
+#include "intel-bts.h"
+#include "util/synthetic-events.h"
+
+#define MAX_TIMESTAMP (~0ULL)
+
+#define INTEL_BTS_ERR_NOINSN  5
+#define INTEL_BTS_ERR_LOST    9
+
+#if __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#define le64_to_cpu bswap_64
+#else
+#define le64_to_cpu
+#endif
+
+struct intel_bts {
+	struct auxtrace			auxtrace;
+	struct auxtrace_queues		queues;
+	struct auxtrace_heap		heap;
+	u32				auxtrace_type;
+	struct perf_session		*session;
+	struct machine			*machine;
+	bool				sampling_mode;
+	bool				snapshot_mode;
+	bool				data_queued;
+	u32				pmu_type;
+	struct perf_tsc_conversion	tc;
+	bool				cap_user_time_zero;
+	struct itrace_synth_opts	synth_opts;
+	bool				sample_branches;
+	u32				branches_filter;
+	u64				branches_sample_type;
+	u64				branches_id;
+	size_t				branches_event_size;
+	unsigned long			num_events;
+};
+
+struct intel_bts_queue {
+	struct intel_bts	*bts;
+	unsigned int		queue_nr;
+	struct auxtrace_buffer	*buffer;
+	bool			on_heap;
+	bool			done;
+	pid_t			pid;
+	pid_t			tid;
+	int			cpu;
+	u64			time;
+	struct intel_pt_insn	intel_pt_insn;
+	u32			sample_flags;
+};
+
+struct branch {
+	u64 from;
+	u64 to;
+	u64 misc;
+};
+
+static void intel_bts_dump(struct intel_bts *bts __maybe_unused,
+			   unsigned char *buf, size_t len)
+{
+	struct branch *branch;
+	size_t i, pos = 0, br_sz = sizeof(struct branch), sz;
+	const char *color = PERF_COLOR_BLUE;
+
+	color_fprintf(stdout, color,
+		      ". ... Intel BTS data: size %zu bytes\n",
+		      len);
+
+	while (len) {
+		if (len >= br_sz)
+			sz = br_sz;
+		else
+			sz = len;
+		printf(".");
+		color_fprintf(stdout, color, "  %08zx: ", pos);
+		for (i = 0; i < sz; i++)
+			color_fprintf(stdout, color, " %02x", buf[i]);
+		for (; i < br_sz; i++)
+			color_fprintf(stdout, color, "   ");
+		if (len >= br_sz) {
+			branch = (struct branch *)buf;
+			color_fprintf(stdout, color, " %"PRIx64" -> %"PRIx64" %s\n",
+				      le64_to_cpu(branch->from),
+				      le64_to_cpu(branch->to),
+				      le64_to_cpu(branch->misc) & 0x10 ?
+							"pred" : "miss");
+		} else {
+			color_fprintf(stdout, color, " Bad record!\n");
+		}
+		pos += sz;
+		buf += sz;
+		len -= sz;
+	}
+}
+
+static void intel_bts_dump_event(struct intel_bts *bts, unsigned char *buf,
+				 size_t len)
+{
+	printf(".\n");
+	intel_bts_dump(bts, buf, len);
+}
+
+static int intel_bts_lost(struct intel_bts *bts, struct perf_sample *sample)
+{
+	union perf_event event;
+	int err;
+
+	auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE,
+			     INTEL_BTS_ERR_LOST, sample->cpu, sample->pid,
+			     sample->tid, 0, "Lost trace data", sample->time);
+
+	err = perf_session__deliver_synth_event(bts->session, &event, NULL);
+	if (err)
+		pr_err("Intel BTS: failed to deliver error event, error %d\n",
+		       err);
+
+	return err;
+}
+
+static struct intel_bts_queue *intel_bts_alloc_queue(struct intel_bts *bts,
+						     unsigned int queue_nr)
+{
+	struct intel_bts_queue *btsq;
+
+	btsq = zalloc(sizeof(struct intel_bts_queue));
+	if (!btsq)
+		return NULL;
+
+	btsq->bts = bts;
+	btsq->queue_nr = queue_nr;
+	btsq->pid = -1;
+	btsq->tid = -1;
+	btsq->cpu = -1;
+
+	return btsq;
+}
+
+static int intel_bts_setup_queue(struct intel_bts *bts,
+				 struct auxtrace_queue *queue,
+				 unsigned int queue_nr)
+{
+	struct intel_bts_queue *btsq = queue->priv;
+
+	if (list_empty(&queue->head))
+		return 0;
+
+	if (!btsq) {
+		btsq = intel_bts_alloc_queue(bts, queue_nr);
+		if (!btsq)
+			return -ENOMEM;
+		queue->priv = btsq;
+
+		if (queue->cpu != -1)
+			btsq->cpu = queue->cpu;
+		btsq->tid = queue->tid;
+	}
+
+	if (bts->sampling_mode)
+		return 0;
+
+	if (!btsq->on_heap && !btsq->buffer) {
+		int ret;
+
+		btsq->buffer = auxtrace_buffer__next(queue, NULL);
+		if (!btsq->buffer)
+			return 0;
+
+		ret = auxtrace_heap__add(&bts->heap, queue_nr,
+					 btsq->buffer->reference);
+		if (ret)
+			return ret;
+		btsq->on_heap = true;
+	}
+
+	return 0;
+}
+
+static int intel_bts_setup_queues(struct intel_bts *bts)
+{
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < bts->queues.nr_queues; i++) {
+		ret = intel_bts_setup_queue(bts, &bts->queues.queue_array[i],
+					    i);
+		if (ret)
+			return ret;
+	}
+	return 0;
+}
+
+static inline int intel_bts_update_queues(struct intel_bts *bts)
+{
+	if (bts->queues.new_data) {
+		bts->queues.new_data = false;
+		return intel_bts_setup_queues(bts);
+	}
+	return 0;
+}
+
+static unsigned char *intel_bts_find_overlap(unsigned char *buf_a, size_t len_a,
+					     unsigned char *buf_b, size_t len_b)
+{
+	size_t offs, len;
+
+	if (len_a > len_b)
+		offs = len_a - len_b;
+	else
+		offs = 0;
+
+	for (; offs < len_a; offs += sizeof(struct branch)) {
+		len = len_a - offs;
+		if (!memcmp(buf_a + offs, buf_b, len))
+			return buf_b + len;
+	}
+
+	return buf_b;
+}
+
+static int intel_bts_do_fix_overlap(struct auxtrace_queue *queue,
+				    struct auxtrace_buffer *b)
+{
+	struct auxtrace_buffer *a;
+	void *start;
+
+	if (b->list.prev == &queue->head)
+		return 0;
+	a = list_entry(b->list.prev, struct auxtrace_buffer, list);
+	start = intel_bts_find_overlap(a->data, a->size, b->data, b->size);
+	if (!start)
+		return -EINVAL;
+	b->use_size = b->data + b->size - start;
+	b->use_data = start;
+	return 0;
+}
+
+static inline u8 intel_bts_cpumode(struct intel_bts *bts, uint64_t ip)
+{
+	return machine__kernel_ip(bts->machine, ip) ?
+	       PERF_RECORD_MISC_KERNEL :
+	       PERF_RECORD_MISC_USER;
+}
+
+static int intel_bts_synth_branch_sample(struct intel_bts_queue *btsq,
+					 struct branch *branch)
+{
+	int ret;
+	struct intel_bts *bts = btsq->bts;
+	union perf_event event;
+	struct perf_sample sample;
+
+	if (bts->synth_opts.initial_skip &&
+	    bts->num_events++ <= bts->synth_opts.initial_skip)
+		return 0;
+
+	perf_sample__init(&sample, /*all=*/true);
+	sample.ip = le64_to_cpu(branch->from);
+	sample.cpumode = intel_bts_cpumode(bts, sample.ip);
+	sample.pid = btsq->pid;
+	sample.tid = btsq->tid;
+	sample.addr = le64_to_cpu(branch->to);
+	sample.id = btsq->bts->branches_id;
+	sample.stream_id = btsq->bts->branches_id;
+	sample.period = 1;
+	sample.cpu = btsq->cpu;
+	sample.flags = btsq->sample_flags;
+	sample.insn_len = btsq->intel_pt_insn.length;
+	memcpy(sample.insn, btsq->intel_pt_insn.buf, INTEL_PT_INSN_BUF_SZ);
+
+	event.sample.header.type = PERF_RECORD_SAMPLE;
+	event.sample.header.misc = sample.cpumode;
+	event.sample.header.size = sizeof(struct perf_event_header);
+
+	if (bts->synth_opts.inject) {
+		event.sample.header.size = bts->branches_event_size;
+		ret = perf_event__synthesize_sample(&event,
+						    bts->branches_sample_type,
+						    /*read_format=*/0, /*branch_sample_type=*/0,
+						    &sample);
+		if (ret)
+			return ret;
+	}
+
+	ret = perf_session__deliver_synth_event(bts->session, &event, &sample);
+	if (ret)
+		pr_err("Intel BTS: failed to deliver branch event, error %d\n",
+		       ret);
+
+	perf_sample__exit(&sample);
+	return ret;
+}
+
+static int intel_bts_get_next_insn(struct intel_bts_queue *btsq, u64 ip)
+{
+	struct machine *machine = btsq->bts->machine;
+	struct thread *thread;
+	unsigned char buf[INTEL_PT_INSN_BUF_SZ];
+	ssize_t len;
+	bool x86_64;
+	int err = -1;
+
+	thread = machine__find_thread(machine, -1, btsq->tid);
+	if (!thread)
+		return -1;
+
+	len = thread__memcpy(thread, machine, buf, ip, INTEL_PT_INSN_BUF_SZ, &x86_64);
+	if (len <= 0)
+		goto out_put;
+
+	if (intel_pt_get_insn(buf, len, x86_64, &btsq->intel_pt_insn))
+		goto out_put;
+
+	err = 0;
+out_put:
+	thread__put(thread);
+	return err;
+}
+
+static int intel_bts_synth_error(struct intel_bts *bts, int cpu, pid_t pid,
+				 pid_t tid, u64 ip)
+{
+	union perf_event event;
+	int err;
+
+	auxtrace_synth_error(&event.auxtrace_error, PERF_AUXTRACE_ERROR_ITRACE,
+			     INTEL_BTS_ERR_NOINSN, cpu, pid, tid, ip,
+			     "Failed to get instruction", 0);
+
+	err = perf_session__deliver_synth_event(bts->session, &event, NULL);
+	if (err)
+		pr_err("Intel BTS: failed to deliver error event, error %d\n",
+		       err);
+
+	return err;
+}
+
+static int intel_bts_get_branch_type(struct intel_bts_queue *btsq,
+				     struct branch *branch)
+{
+	int err;
+
+	if (!branch->from) {
+		if (branch->to)
+			btsq->sample_flags = PERF_IP_FLAG_BRANCH |
+					     PERF_IP_FLAG_TRACE_BEGIN;
+		else
+			btsq->sample_flags = 0;
+		btsq->intel_pt_insn.length = 0;
+	} else if (!branch->to) {
+		btsq->sample_flags = PERF_IP_FLAG_BRANCH |
+				     PERF_IP_FLAG_TRACE_END;
+		btsq->intel_pt_insn.length = 0;
+	} else {
+		err = intel_bts_get_next_insn(btsq, branch->from);
+		if (err) {
+			btsq->sample_flags = 0;
+			btsq->intel_pt_insn.length = 0;
+			if (!btsq->bts->synth_opts.errors)
+				return 0;
+			err = intel_bts_synth_error(btsq->bts, btsq->cpu,
+						    btsq->pid, btsq->tid,
+						    branch->from);
+			return err;
+		}
+		btsq->sample_flags = intel_pt_insn_type(btsq->intel_pt_insn.op);
+		/* Check for an async branch into the kernel */
+		if (!machine__kernel_ip(btsq->bts->machine, branch->from) &&
+		    machine__kernel_ip(btsq->bts->machine, branch->to) &&
+		    btsq->sample_flags != (PERF_IP_FLAG_BRANCH |
+					   PERF_IP_FLAG_CALL |
+					   PERF_IP_FLAG_SYSCALLRET))
+			btsq->sample_flags = PERF_IP_FLAG_BRANCH |
+					     PERF_IP_FLAG_CALL |
+					     PERF_IP_FLAG_ASYNC |
+					     PERF_IP_FLAG_INTERRUPT;
+	}
+
+	return 0;
+}
+
+static int intel_bts_process_buffer(struct intel_bts_queue *btsq,
+				    struct auxtrace_buffer *buffer,
+				    struct thread *thread)
+{
+	struct branch *branch;
+	size_t sz, bsz = sizeof(struct branch);
+	u32 filter = btsq->bts->branches_filter;
+	int err = 0;
+
+	if (buffer->use_data) {
+		sz = buffer->use_size;
+		branch = buffer->use_data;
+	} else {
+		sz = buffer->size;
+		branch = buffer->data;
+	}
+
+	if (!btsq->bts->sample_branches)
+		return 0;
+
+	for (; sz > bsz; branch += 1, sz -= bsz) {
+		if (!branch->from && !branch->to)
+			continue;
+		intel_bts_get_branch_type(btsq, branch);
+		if (btsq->bts->synth_opts.thread_stack)
+			thread_stack__event(thread, btsq->cpu, btsq->sample_flags,
+					    le64_to_cpu(branch->from),
+					    le64_to_cpu(branch->to),
+					    btsq->intel_pt_insn.length,
+					    buffer->buffer_nr + 1, true, 0, 0);
+		if (filter && !(filter & btsq->sample_flags))
+			continue;
+		err = intel_bts_synth_branch_sample(btsq, branch);
+		if (err)
+			break;
+	}
+	return err;
+}
+
+static int intel_bts_process_queue(struct intel_bts_queue *btsq, u64 *timestamp)
+{
+	struct auxtrace_buffer *buffer = btsq->buffer, *old_buffer = buffer;
+	struct auxtrace_queue *queue;
+	struct thread *thread;
+	int err;
+
+	if (btsq->done)
+		return 1;
+
+	if (btsq->pid == -1) {
+		thread = machine__find_thread(btsq->bts->machine, -1,
+					      btsq->tid);
+		if (thread)
+			btsq->pid = thread__pid(thread);
+	} else {
+		thread = machine__findnew_thread(btsq->bts->machine, btsq->pid,
+						 btsq->tid);
+	}
+
+	queue = &btsq->bts->queues.queue_array[btsq->queue_nr];
+
+	if (!buffer)
+		buffer = auxtrace_buffer__next(queue, NULL);
+
+	if (!buffer) {
+		if (!btsq->bts->sampling_mode)
+			btsq->done = 1;
+		err = 1;
+		goto out_put;
+	}
+
+	/* Currently there is no support for split buffers */
+	if (buffer->consecutive) {
+		err = -EINVAL;
+		goto out_put;
+	}
+
+	if (!buffer->data) {
+		int fd = perf_data__fd(btsq->bts->session->data);
+
+		buffer->data = auxtrace_buffer__get_data(buffer, fd);
+		if (!buffer->data) {
+			err = -ENOMEM;
+			goto out_put;
+		}
+	}
+
+	if (btsq->bts->snapshot_mode && !buffer->consecutive &&
+	    intel_bts_do_fix_overlap(queue, buffer)) {
+		err = -ENOMEM;
+		goto out_put;
+	}
+
+	if (!btsq->bts->synth_opts.callchain &&
+	    !btsq->bts->synth_opts.thread_stack && thread &&
+	    (!old_buffer || btsq->bts->sampling_mode ||
+	     (btsq->bts->snapshot_mode && !buffer->consecutive)))
+		thread_stack__set_trace_nr(thread, btsq->cpu, buffer->buffer_nr + 1);
+
+	err = intel_bts_process_buffer(btsq, buffer, thread);
+
+	auxtrace_buffer__drop_data(buffer);
+
+	btsq->buffer = auxtrace_buffer__next(queue, buffer);
+	if (btsq->buffer) {
+		if (timestamp)
+			*timestamp = btsq->buffer->reference;
+	} else {
+		if (!btsq->bts->sampling_mode)
+			btsq->done = 1;
+	}
+out_put:
+	thread__put(thread);
+	return err;
+}
+
+static int intel_bts_flush_queue(struct intel_bts_queue *btsq)
+{
+	u64 ts = 0;
+	int ret;
+
+	while (1) {
+		ret = intel_bts_process_queue(btsq, &ts);
+		if (ret < 0)
+			return ret;
+		if (ret)
+			break;
+	}
+	return 0;
+}
+
+static int intel_bts_process_tid_exit(struct intel_bts *bts, pid_t tid)
+{
+	struct auxtrace_queues *queues = &bts->queues;
+	unsigned int i;
+
+	for (i = 0; i < queues->nr_queues; i++) {
+		struct auxtrace_queue *queue = &bts->queues.queue_array[i];
+		struct intel_bts_queue *btsq = queue->priv;
+
+		if (btsq && btsq->tid == tid)
+			return intel_bts_flush_queue(btsq);
+	}
+	return 0;
+}
+
+static int intel_bts_process_queues(struct intel_bts *bts, u64 timestamp)
+{
+	while (1) {
+		unsigned int queue_nr;
+		struct auxtrace_queue *queue;
+		struct intel_bts_queue *btsq;
+		u64 ts = 0;
+		int ret;
+
+		if (!bts->heap.heap_cnt)
+			return 0;
+
+		if (bts->heap.heap_array[0].ordinal > timestamp)
+			return 0;
+
+		queue_nr = bts->heap.heap_array[0].queue_nr;
+		queue = &bts->queues.queue_array[queue_nr];
+		btsq = queue->priv;
+
+		auxtrace_heap__pop(&bts->heap);
+
+		ret = intel_bts_process_queue(btsq, &ts);
+		if (ret < 0) {
+			auxtrace_heap__add(&bts->heap, queue_nr, ts);
+			return ret;
+		}
+
+		if (!ret) {
+			ret = auxtrace_heap__add(&bts->heap, queue_nr, ts);
+			if (ret < 0)
+				return ret;
+		} else {
+			btsq->on_heap = false;
+		}
+	}
+
+	return 0;
+}
+
+static int intel_bts_process_event(struct perf_session *session,
+				   union perf_event *event,
+				   struct perf_sample *sample,
+				   const struct perf_tool *tool)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+	u64 timestamp;
+	int err;
+
+	if (dump_trace)
+		return 0;
+
+	if (!tool->ordered_events) {
+		pr_err("Intel BTS requires ordered events\n");
+		return -EINVAL;
+	}
+
+	if (sample->time && sample->time != (u64)-1)
+		timestamp = perf_time_to_tsc(sample->time, &bts->tc);
+	else
+		timestamp = 0;
+
+	err = intel_bts_update_queues(bts);
+	if (err)
+		return err;
+
+	err = intel_bts_process_queues(bts, timestamp);
+	if (err)
+		return err;
+	if (event->header.type == PERF_RECORD_EXIT) {
+		err = intel_bts_process_tid_exit(bts, event->fork.tid);
+		if (err)
+			return err;
+	}
+
+	if (event->header.type == PERF_RECORD_AUX &&
+	    (event->aux.flags & PERF_AUX_FLAG_TRUNCATED) &&
+	    bts->synth_opts.errors)
+		err = intel_bts_lost(bts, sample);
+
+	return err;
+}
+
+static int intel_bts_process_auxtrace_event(struct perf_session *session,
+					    union perf_event *event,
+					    const struct perf_tool *tool __maybe_unused)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+
+	if (bts->sampling_mode)
+		return 0;
+
+	if (!bts->data_queued) {
+		struct auxtrace_buffer *buffer;
+		off_t data_offset;
+		int fd = perf_data__fd(session->data);
+		int err;
+
+		if (perf_data__is_pipe(session->data)) {
+			data_offset = 0;
+		} else {
+			data_offset = lseek(fd, 0, SEEK_CUR);
+			if (data_offset == -1)
+				return -errno;
+		}
+
+		err = auxtrace_queues__add_event(&bts->queues, session, event,
+						 data_offset, &buffer);
+		if (err)
+			return err;
+
+		/* Dump here now we have copied a piped trace out of the pipe */
+		if (dump_trace) {
+			if (auxtrace_buffer__get_data(buffer, fd)) {
+				intel_bts_dump_event(bts, buffer->data,
+						     buffer->size);
+				auxtrace_buffer__put_data(buffer);
+			}
+		}
+	}
+
+	return 0;
+}
+
+static int intel_bts_flush(struct perf_session *session,
+			   const struct perf_tool *tool __maybe_unused)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+	int ret;
+
+	if (dump_trace || bts->sampling_mode)
+		return 0;
+
+	if (!tool->ordered_events)
+		return -EINVAL;
+
+	ret = intel_bts_update_queues(bts);
+	if (ret < 0)
+		return ret;
+
+	return intel_bts_process_queues(bts, MAX_TIMESTAMP);
+}
+
+static void intel_bts_free_queue(void *priv)
+{
+	struct intel_bts_queue *btsq = priv;
+
+	if (!btsq)
+		return;
+	free(btsq);
+}
+
+static void intel_bts_free_events(struct perf_session *session)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+	struct auxtrace_queues *queues = &bts->queues;
+	unsigned int i;
+
+	for (i = 0; i < queues->nr_queues; i++) {
+		intel_bts_free_queue(queues->queue_array[i].priv);
+		queues->queue_array[i].priv = NULL;
+	}
+	auxtrace_queues__free(queues);
+}
+
+static void intel_bts_free(struct perf_session *session)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+
+	auxtrace_heap__free(&bts->heap);
+	intel_bts_free_events(session);
+	session->auxtrace = NULL;
+	free(bts);
+}
+
+static bool intel_bts_evsel_is_auxtrace(struct perf_session *session,
+					struct evsel *evsel)
+{
+	struct intel_bts *bts = container_of(session->auxtrace, struct intel_bts,
+					     auxtrace);
+
+	return evsel->core.attr.type == bts->pmu_type;
+}
+
+static int intel_bts_synth_events(struct intel_bts *bts,
+				  struct perf_session *session)
+{
+	struct evlist *evlist = session->evlist;
+	struct evsel *evsel;
+	struct perf_event_attr attr;
+	bool found = false;
+	u64 id;
+	int err;
+
+	evlist__for_each_entry(evlist, evsel) {
+		if (evsel->core.attr.type == bts->pmu_type && evsel->core.ids) {
+			found = true;
+			break;
+		}
+	}
+
+	if (!found) {
+		pr_debug("There are no selected events with Intel BTS data\n");
+		return 0;
+	}
+
+	memset(&attr, 0, sizeof(struct perf_event_attr));
+	attr.size = sizeof(struct perf_event_attr);
+	attr.type = PERF_TYPE_HARDWARE;
+	attr.sample_type = evsel->core.attr.sample_type & PERF_SAMPLE_MASK;
+	attr.sample_type |= PERF_SAMPLE_IP | PERF_SAMPLE_TID |
+			    PERF_SAMPLE_PERIOD;
+	attr.sample_type &= ~(u64)PERF_SAMPLE_TIME;
+	attr.sample_type &= ~(u64)PERF_SAMPLE_CPU;
+	attr.exclude_user = evsel->core.attr.exclude_user;
+	attr.exclude_kernel = evsel->core.attr.exclude_kernel;
+	attr.exclude_hv = evsel->core.attr.exclude_hv;
+	attr.exclude_host = evsel->core.attr.exclude_host;
+	attr.exclude_guest = evsel->core.attr.exclude_guest;
+	attr.sample_id_all = evsel->core.attr.sample_id_all;
+	attr.read_format = evsel->core.attr.read_format;
+
+	id = auxtrace_synth_id_range_start(evsel);
+
+	if (bts->synth_opts.branches) {
+		attr.config = PERF_COUNT_HW_BRANCH_INSTRUCTIONS;
+		attr.sample_period = 1;
+		attr.sample_type |= PERF_SAMPLE_ADDR;
+		pr_debug("Synthesizing 'branches' event with id %" PRIu64 " sample type %#" PRIx64 "\n",
+			 id, (u64)attr.sample_type);
+		err = perf_session__deliver_synth_attr_event(session, &attr, id);
+		if (err) {
+			pr_err("%s: failed to synthesize 'branches' event type\n",
+			       __func__);
+			return err;
+		}
+		bts->sample_branches = true;
+		bts->branches_sample_type = attr.sample_type;
+		bts->branches_id = id;
+		/*
+		 * We only use sample types from PERF_SAMPLE_MASK so we can use
+		 * __evsel__sample_size() here.
+		 */
+		bts->branches_event_size = sizeof(struct perf_record_sample) +
+					   __evsel__sample_size(attr.sample_type);
+	}
+
+	return 0;
+}
+
+static const char * const intel_bts_info_fmts[] = {
+	[INTEL_BTS_PMU_TYPE]		= "  PMU Type           %"PRId64"\n",
+	[INTEL_BTS_TIME_SHIFT]		= "  Time Shift         %"PRIu64"\n",
+	[INTEL_BTS_TIME_MULT]		= "  Time Multiplier    %"PRIu64"\n",
+	[INTEL_BTS_TIME_ZERO]		= "  Time Zero          %"PRIu64"\n",
+	[INTEL_BTS_CAP_USER_TIME_ZERO]	= "  Cap Time Zero      %"PRId64"\n",
+	[INTEL_BTS_SNAPSHOT_MODE]	= "  Snapshot mode      %"PRId64"\n",
+};
+
+static void intel_bts_print_info(__u64 *arr, int start, int finish)
+{
+	int i;
+
+	if (!dump_trace)
+		return;
+
+	for (i = start; i <= finish; i++)
+		fprintf(stdout, intel_bts_info_fmts[i], arr[i]);
+}
+
+int intel_bts_process_auxtrace_info(union perf_event *event,
+				    struct perf_session *session)
+{
+	struct perf_record_auxtrace_info *auxtrace_info = &event->auxtrace_info;
+	size_t min_sz = sizeof(u64) * (INTEL_BTS_SNAPSHOT_MODE + 1);
+	struct intel_bts *bts;
+	int err;
+
+	if (auxtrace_info->header.size < sizeof(struct perf_record_auxtrace_info) +
+					min_sz)
+		return -EINVAL;
+
+	bts = zalloc(sizeof(struct intel_bts));
+	if (!bts)
+		return -ENOMEM;
+
+	err = auxtrace_queues__init(&bts->queues);
+	if (err)
+		goto err_free;
+
+	bts->session = session;
+	bts->machine = &session->machines.host; /* No kvm support */
+	bts->auxtrace_type = auxtrace_info->type;
+	bts->pmu_type = auxtrace_info->priv[INTEL_BTS_PMU_TYPE];
+	bts->tc.time_shift = auxtrace_info->priv[INTEL_BTS_TIME_SHIFT];
+	bts->tc.time_mult = auxtrace_info->priv[INTEL_BTS_TIME_MULT];
+	bts->tc.time_zero = auxtrace_info->priv[INTEL_BTS_TIME_ZERO];
+	bts->cap_user_time_zero =
+			auxtrace_info->priv[INTEL_BTS_CAP_USER_TIME_ZERO];
+	bts->snapshot_mode = auxtrace_info->priv[INTEL_BTS_SNAPSHOT_MODE];
+
+	bts->sampling_mode = false;
+
+	bts->auxtrace.process_event = intel_bts_process_event;
+	bts->auxtrace.process_auxtrace_event = intel_bts_process_auxtrace_event;
+	bts->auxtrace.flush_events = intel_bts_flush;
+	bts->auxtrace.free_events = intel_bts_free_events;
+	bts->auxtrace.free = intel_bts_free;
+	bts->auxtrace.evsel_is_auxtrace = intel_bts_evsel_is_auxtrace;
+	session->auxtrace = &bts->auxtrace;
+
+	intel_bts_print_info(&auxtrace_info->priv[0], INTEL_BTS_PMU_TYPE,
+			     INTEL_BTS_SNAPSHOT_MODE);
+
+	if (dump_trace)
+		return 0;
+
+	if (session->itrace_synth_opts->set) {
+		bts->synth_opts = *session->itrace_synth_opts;
+	} else {
+		itrace_synth_opts__set_default(&bts->synth_opts,
+				session->itrace_synth_opts->default_no_sample);
+		bts->synth_opts.thread_stack =
+				session->itrace_synth_opts->thread_stack;
+	}
+
+	if (bts->synth_opts.calls)
+		bts->branches_filter |= PERF_IP_FLAG_CALL | PERF_IP_FLAG_ASYNC |
+					PERF_IP_FLAG_TRACE_END;
+	if (bts->synth_opts.returns)
+		bts->branches_filter |= PERF_IP_FLAG_RETURN |
+					PERF_IP_FLAG_TRACE_BEGIN;
+
+	err = intel_bts_synth_events(bts, session);
+	if (err)
+		goto err_free_queues;
+
+	err = auxtrace_queues__process_index(&bts->queues, session);
+	if (err)
+		goto err_free_queues;
+
+	if (bts->queues.populated)
+		bts->data_queued = true;
+
+	return 0;
+
+err_free_queues:
+	auxtrace_queues__free(&bts->queues);
+	session->auxtrace = NULL;
+err_free:
+	free(bts);
+	return err;
+}