Commit fd28754d authored by Nick Mathewson's avatar Nick Mathewson 🥔
Browse files

Actually release buffer freelists when handling OOM conditions. 

Otherwise freeing buffers won't help for a little while.
parent 79515917

src/or/buffers.c

+7 −2
Original line number Diff line number Diff line
@@ -276,12 +276,14 @@ preferred_chunk_size(size_t target) 
}



/** Remove from the freelists most chunks that have not been used since the

 * last call to buf_shrink_freelists(). */

void

 * last call to buf_shrink_freelists().   Return the amount of memory

 * freed. */

size_t

buf_shrink_freelists(int free_all)

{

#ifdef ENABLE_BUF_FREELISTS

  int i;

  size_t total_freed = 0;

  disable_control_logging();

  for (i = 0; freelists[i].alloc_size; ++i) {

    int slack = freelists[i].slack;
@@ -315,6 +317,7 @@ buf_shrink_freelists(int free_all) 
        chunk_t *next = chunk->next;

        tor_assert(total_bytes_allocated_in_chunks >= CHUNK_ALLOC_SIZE(chunk->memlen));

        total_bytes_allocated_in_chunks -= CHUNK_ALLOC_SIZE(chunk->memlen);

        total_freed += CHUNK_ALLOC_SIZE(chunk->memlen);

        tor_free(chunk);

        chunk = next;

        --n_to_free;
@@ -343,8 +346,10 @@ buf_shrink_freelists(int free_all) 
  }

 done:

  enable_control_logging();

  return total_freed;

#else

  (void) free_all;

  return 0;

#endif

}

src/or/buffers.h

+1 −1
Original line number Diff line number Diff line
@@ -18,7 +18,7 @@ void buf_free(buf_t *buf); 
void buf_clear(buf_t *buf);

buf_t *buf_copy(const buf_t *buf);

void buf_shrink(buf_t *buf);

void buf_shrink_freelists(int free_all);

size_t buf_shrink_freelists(int free_all);

void buf_dump_freelist_sizes(int severity);



size_t buf_datalen(const buf_t *buf);

src/or/circuitlist.c

+13 −0
Original line number Diff line number Diff line
@@ -1532,6 +1532,17 @@ circuits_handle_oom(size_t current_allocation) 
             "over-long queues. (This behavior is controlled by "

             "MaxMemInQueues.)");



  {

    const size_t recovered = buf_shrink_freelists(1);

    if (recovered >= current_allocation) {

      log_warn(LD_BUG, "We somehow recovered more memory from freelists "

               "than we thought we had allocated");

      current_allocation = 0;

    } else {

      current_allocation -= recovered;

    }

  }



  {

    size_t mem_target = (size_t)(get_options()->MaxMemInQueues *

                                 FRACTION_OF_DATA_TO_RETAIN_ON_OOM);
@@ -1575,6 +1586,8 @@ circuits_handle_oom(size_t current_allocation) 
  } SMARTLIST_FOREACH_END(circ);



  clean_cell_pool(); /* In case this helps. */

  buf_shrink_freelists(1); /* This is necessary to actually release buffer

                              chunks. */



  log_notice(LD_GENERAL, "Removed "U64_FORMAT" bytes by killing %d circuits.",

             U64_PRINTF_ARG(mem_recovered),