// SPDX-License-Identifier: GPL-2.0
#include <errno.h>
#include <inttypes.h>
#include <linux/list.h>
#include <linux/compiler.h>
#include <linux/string.h>
#include "ordered-events.h"
#include "session.h"
#include "asm/bug.h"
#include "debug.h"
#include "ui/progress.h"
#define pr_N(n, fmt, ...) \
eprintf(n, debug_ordered_events, fmt, ##__VA_ARGS__)
#define pr(fmt, ...) pr_N(1, pr_fmt(fmt), ##__VA_ARGS__)
static void queue_event(struct ordered_events *oe, struct ordered_event *new)
{
struct ordered_event *last = oe->last;
u64 timestamp = new->timestamp;
struct list_head *p;
++oe->nr_events;
oe->last = new;
pr_oe_time2(timestamp, "queue_event nr_events %u\n", oe->nr_events);
if (!last) {
list_add(&new->list, &oe->events);
oe->max_timestamp = timestamp;
return;
}
/*
* last event might point to some random place in the list as it's
* the last queued event. We expect that the new event is close to
* this.
*/
if (last->timestamp <= timestamp) {
while (last->timestamp <= timestamp) {
p = last->list.next;
if (p == &oe->events) {
list_add_tail(&new->list, &oe->events);
oe->max_timestamp = timestamp;
return;
}
last = list_entry(p, struct ordered_event, list);
}
list_add_tail(&new->list, &last->list);
} else {
while (last->timestamp > timestamp) {
p = last->list.prev;
if (p == &oe->events) {
list_add(&new->list, &oe->events);
return;
}
last = list_entry(p, struct ordered_event, list);
}
list_add(&new->list, &last->list);
}
}
static union perf_event *__dup_event(struct ordered_events *oe,
union perf_event *event)
{
union perf_event *new_event = NULL;
if (oe->cur_alloc_size < oe->max_alloc_size) {
new_event = memdup(event, event->header.size);
if (new_event)
oe->cur_alloc_size += event->header.size;
}
return new_event;
}
static union perf_event *dup_event(struct ordered_events *oe,
union perf_event *event)
{
return oe->copy_on_queue ? __dup_event(oe, event) : event;
}
static void __free_dup_event(struct ordered_events *oe, union perf_event *event)
{
if (event) {
oe->cur_alloc_size -= event->header.size;
free(event);
}
}
static void free_dup_event(struct ordered_events *oe, union perf_event *event)
{
if (oe->copy_on_queue)
__free_dup_event(oe, event);
}
#define MAX_SAMPLE_BUFFER (64 * 1024 / sizeof(struct ordered_event))
static struct ordered_event *alloc_event(struct ordered_events *oe,
union perf_event *event)
{
struct list_head *cache = &oe->cache;
struct ordered_event *new = NULL;
union perf_event *new_event;
size_t size;
new_event = dup_event(oe, event);
if (!new_event)
return NULL;
/*
* We maintain the following scheme of buffers for ordered
* event allocation:
*
* to_free list -> buffer1 (64K)
* buffer2 (64K)
* ...
*
* Each buffer keeps an array of ordered events objects:
* buffer -> event[0]
* event[1]
* ...
*
* Each allocated ordered event is linked to one of
* following lists:
* - time ordered list 'events'
* - list of currently removed events 'cache'
*
* Allocation of the ordered event uses the following order
* to get the memory:
* - use recently removed object from 'cache' list
* - use available object in current allocation buffer
* - allocate new buffer if the current buffer is full
*
* Removal of ordered event object moves it from events to
* the cache list.
*/
size = sizeof(*oe->buffer) + MAX_SAMPLE_BUFFER * sizeof(*new);
if (!list_empty(cache)) {
new = list_entry(cache->next, struct ordered_event, list);
list_del_init(&new->list);
} else if (oe->buffer) {
new = &oe->buffer->event[oe->buffer_idx];
if (++oe->buffer_idx == MAX_SAMPLE_BUFFER)
oe->buffer = NULL;
} else if ((oe->cur_alloc_size + size) < oe->max_alloc_size) {
oe->buffer = malloc(size);
if (!oe->buffer) {
free_dup_event(oe, new_event);
return NULL;
}
pr("alloc size %" PRIu64 "B (+%zu), max %" PRIu64 "B\n",
oe->cur_alloc_size, size, oe->max_alloc_size);
oe->cur_alloc_size += size;
list_add(&oe->buffer->list, &oe->to_free);
oe->buffer_idx = 1;
new = &oe->buffer->event[0];
} else {
pr("allocation limit reached %" PRIu64 "B\n", oe->max_alloc_size);
return NULL;
}
new->event = new_event;
return new;
}
static struct ordered_event *
ordered_events__new_event(struct ordered_events *oe, u64 timestamp,
union perf_event *event)
{
struct ordered_event *new;
new = alloc_event(oe, event);
if (new) {
new->timestamp = timestamp;
queue_event(oe, new);
}
return new;
}
void ordered_events__delete(struct ordered_events *oe, struct ordered_event *event)
{
list_move(&event->list, &oe->cache);
oe->nr_events--;
free_dup_event(oe, event->event);
event->event = NULL;
}
int ordered_events__queue(struct ordered_events *oe, union perf_event *event,
u64 timestamp, u64 file_offset, const char *file_path)
{
struct ordered_event *oevent;
if (!timestamp || timestamp == ~0ULL)
return -ETIME;
if (timestamp < oe->last_flush) {
pr_oe_time(timestamp, "out of order event\n");
pr_oe_time(oe->last_flush, "last flush, last_flush_type %d\n",
oe->last_flush_type);
oe->nr_unordered_events++;
}
oevent = ordered_events__new_event(oe, timestamp, event);
if (!oevent) {
ordered_events__flush(oe, OE_FLUSH__HALF);
oevent = ordered_events__new_event(oe, timestamp, event);
}
if (!oevent)
return -ENOMEM;
oevent->file_offset = file_offset;
oevent->file_path = file_path;
return 0;
}
static int do_flush(struct ordered_events *oe, bool show_progress)
{
struct list_head *head = &oe->events;
struct ordered_event *tmp, *iter;
u64 limit = oe->next_flush;
u64 last_ts = oe->last ? oe->last->timestamp : 0ULL;
struct ui_progress prog;
int ret;
if (!limit)
return 0;
if (show_progress)
ui_progress__init(&prog, oe->nr_events, "Processing time ordered events...");
list_for_each_entry_safe(iter, tmp, head, list) {
if (session_done())
return 0;
if (iter->timestamp > limit)
break;
ret = oe->deliver(oe, iter);
if (ret)
return ret;
ordered_events__delete(oe, iter);
oe->last_flush = iter->timestamp;
if (show_progress)
ui_progress__update(&prog, 1);
}
if (list_empty(head))
oe->last = NULL;
else if (last_ts <= limit)
oe->last = list_entry(head->prev, struct ordered_event, list);
if (show_progress)
ui_progress__finish();
return 0;
}
static int __ordered_events__flush(struct ordered_events *oe, enum oe_flush how,
u64 timestamp)
{
static const char * const str[] = {
"NONE",
"FINAL",
"ROUND",
"HALF ",
"TOP ",
"TIME ",
};
int err;
bool show_progress = false;
if (oe->nr_events == 0)
return 0;
switch (how) {
case OE_FLUSH__FINAL:
show_progress = true;
fallthrough;
case OE_FLUSH__TOP:
oe->next_flush = ULLONG_MAX;
break;
case OE_FLUSH__HALF:
{
struct ordered_event *first, *last;
struct list_head *head = &oe->events;
first = list_entry(head->next, struct ordered_event, list);
last = oe->last;
/* Warn if we are called before any event got allocated. */
if (WARN_ONCE(!last || list_empty(head), "empty queue"))
return 0;
oe->next_flush = first->timestamp;
oe->next_flush += (last->timestamp - first->timestamp) / 2;
break;
}
case OE_FLUSH__TIME:
oe->next_flush = timestamp;
show_progress = false;
break;
case OE_FLUSH__ROUND:
case OE_FLUSH__NONE:
default:
break;
}
pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush PRE %s, nr_events %u\n",
str[how], oe->nr_events);
pr_oe_time(oe->max_timestamp, "max_timestamp\n");
err = do_flush(oe, show_progress);
if (!err) {
if (how == OE_FLUSH__ROUND)
oe->next_flush = oe->max_timestamp;
oe->last_flush_type = how;
}
pr_oe_time(oe->next_flush, "next_flush - ordered_events__flush POST %s, nr_events %u\n",
str[how], oe->nr_events);
pr_oe_time(oe->last_flush, "last_flush\n");
return err;
}
int ordered_events__flush(struct ordered_events *oe, enum oe_flush how)
{
return __ordered_events__flush(oe, how, 0);
}
int ordered_events__flush_time(struct ordered_events *oe, u64 timestamp)
{
return __ordered_events__flush(oe, OE_FLUSH__TIME, timestamp);
}
u64 ordered_events__first_time(struct ordered_events *oe)
{
struct ordered_event *event;
if (list_empty(&oe->events))
return 0;
event = list_first_entry(&oe->events, struct ordered_event, list);
return event->timestamp;
}
void ordered_events__init(struct ordered_events *oe, ordered_events__deliver_t deliver,
void *data)
{
INIT_LIST_HEAD(&oe->events);
INIT_LIST_HEAD(&oe->cache);
INIT_LIST_HEAD(&oe->to_free);
oe->max_alloc_size = (u64) -1;
oe->cur_alloc_size = 0;
oe->deliver = deliver;
oe->data = data;
}
static void
ordered_events_buffer__free(struct ordered_events_buffer *buffer,
unsigned int max, struct ordered_events *oe)
{
if (oe->copy_on_queue) {
unsigned int i;
for (i = 0; i < max; i++)
__free_dup_event(oe, buffer->event[i].event);
}
free(buffer);
}
void ordered_events__free(struct ordered_events *oe)
{
struct ordered_events_buffer *buffer, *tmp;
if (list_empty(&oe->to_free))
return;
/*
* Current buffer might not have all the events allocated
* yet, we need to free only allocated ones ...
*/
if (oe->buffer) {
list_del_init(&oe->buffer->list);
ordered_events_buffer__free(oe->buffer, oe->buffer_idx, oe);
}
/* ... and continue with the rest */
list_for_each_entry_safe(buffer, tmp, &oe->to_free, list) {
list_del_init(&buffer->list);
ordered_events_buffer__free(buffer, MAX_SAMPLE_BUFFER, oe);
}
}
void ordered_events__reinit(struct ordered_events *oe)
{
ordered_events__deliver_t old_deliver = oe->deliver;
ordered_events__free(oe);
memset(oe, '\0', sizeof(*oe));
ordered_events__init(oe, old_deliver, oe->data);
}
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