Merge pull request iovisor#3817 from chenhengqi/update-perf-buffer

bcc: Update perf buffer C++ API
GaoHuijian · Jan 17, 2022 · 3ac3c5d · 3ac3c5d
2 parents 5e8125c + a517668
commit 3ac3c5d
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Showing 2 changed files with 35 additions and 11 deletions.
diff --git a/src/cc/api/BPFTable.cc b/src/cc/api/BPFTable.cc
@@ -397,21 +397,21 @@ BPFPerfBuffer::BPFPerfBuffer(const TableDesc& desc)
  "' is not a perf buffer");
 }
 
-StatusTuple BPFPerfBuffer::open_on_cpu(perf_reader_raw_cb cb,
- perf_reader_lost_cb lost_cb, int cpu,
- void* cb_cookie, int page_cnt) {
- if (cpu_readers_.find(cpu) != cpu_readers_.end())
- return StatusTuple(-1, "Perf buffer already open on CPU %d", cpu);
+StatusTuple BPFPerfBuffer::open_on_cpu(perf_reader_raw_cb cb, perf_reader_lost_cb lost_cb,
+ void* cb_cookie, int page_cnt,
+ struct bcc_perf_buffer_opts& opts) {
+ if (cpu_readers_.find(opts.cpu) != cpu_readers_.end())
+ return StatusTuple(-1, "Perf buffer already open on CPU %d", opts.cpu);
 
  auto reader = static_cast<perf_reader*>(
- bpf_open_perf_buffer(cb, lost_cb, cb_cookie, -1, cpu, page_cnt));
+ bpf_open_perf_buffer_opts(cb, lost_cb, cb_cookie, page_cnt, &opts));
  if (reader == nullptr)
  return StatusTuple(-1, "Unable to construct perf reader");
 
  int reader_fd = perf_reader_fd(reader);
- if (!update(&cpu, &reader_fd)) {
+ if (!update(&opts.cpu, &reader_fd)) {
  perf_reader_free(static_cast<void*>(reader));
- return StatusTuple(-1, "Unable to open perf buffer on CPU %d: %s", cpu,
+ return StatusTuple(-1, "Unable to open perf buffer on CPU %d: %s", opts.cpu,
  std::strerror(errno));
  }
 
@@ -424,13 +424,21 @@ StatusTuple BPFPerfBuffer::open_on_cpu(perf_reader_raw_cb cb,
  std::strerror(errno));
  }
 
- cpu_readers_[cpu] = reader;
+ cpu_readers_[opts.cpu] = reader;
  return StatusTuple::OK();
 }
 
 StatusTuple BPFPerfBuffer::open_all_cpu(perf_reader_raw_cb cb,
  perf_reader_lost_cb lost_cb,
  void* cb_cookie, int page_cnt) {
+ return open_all_cpu(cb, lost_cb, cb_cookie, page_cnt, 1);
+}
+
+StatusTuple BPFPerfBuffer::open_all_cpu(perf_reader_raw_cb cb,
+ perf_reader_lost_cb lost_cb,
+ void* cb_cookie, int page_cnt,
+ int wakeup_events)
+{
  if (cpu_readers_.size() != 0 || epfd_ != -1)
  return StatusTuple(-1, "Previously opened perf buffer not cleaned");
 
@@ -439,7 +447,12 @@ StatusTuple BPFPerfBuffer::open_all_cpu(perf_reader_raw_cb cb,
  epfd_ = epoll_create1(EPOLL_CLOEXEC);
 
  for (int i : cpus) {
- auto res = open_on_cpu(cb, lost_cb, i, cb_cookie, page_cnt);
+ struct bcc_perf_buffer_opts opts = {
+ .pid = -1,
+ .cpu = i,
+ .wakeup_events = wakeup_events,
+ };
+ auto res = open_on_cpu(cb, lost_cb, cb_cookie, page_cnt, opts);
  if (!res.ok()) {
  TRY2(close_all_cpu());
  return res;
@@ -500,6 +513,14 @@ int BPFPerfBuffer::poll(int timeout_ms) {
  return cnt;
 }
 
+int BPFPerfBuffer::consume() {
+ if (epfd_ < 0)
+ return -1;
+ for (auto it : cpu_readers_)
+ perf_reader_event_read(it.second);
+ return 0;
+}
+
 BPFPerfBuffer::~BPFPerfBuffer() {
  auto res = close_all_cpu();
  if (!res.ok())

diff --git a/src/cc/api/BPFTable.h b/src/cc/api/BPFTable.h
@@ -415,12 +415,15 @@ class BPFPerfBuffer : public BPFTableBase<int, int> {
 
  StatusTuple open_all_cpu(perf_reader_raw_cb cb, perf_reader_lost_cb lost_cb,
  void* cb_cookie, int page_cnt);
+ StatusTuple open_all_cpu(perf_reader_raw_cb cb, perf_reader_lost_cb lost_cb,
+ void* cb_cookie, int page_cnt, int wakeup_events);
  StatusTuple close_all_cpu();
  int poll(int timeout_ms);
+ int consume();
 
  private:
  StatusTuple open_on_cpu(perf_reader_raw_cb cb, perf_reader_lost_cb lost_cb,
- int cpu, void* cb_cookie, int page_cnt);
+ void* cb_cookie, int page_cnt, struct bcc_perf_buffer_opts& opts);
  StatusTuple close_on_cpu(int cpu);
 
  std::map<int, perf_reader*> cpu_readers_;