Merge 10.2 into 10.3

Author: dr-m

storage/innobase/include/log0log.h

@@ -527,7 +527,7 @@ struct log_t{
 to the first half before freeing/resizing
 must be undertaken. */
 boolfirst_in_use;/*!< true if buf points to the first
-half of the aligned(buf_ptr), false
+half of the buffer, false
 if the second half */
 ulong	max_buf_free;/*!< recommended maximum value of
 buf_free for the buffer in use, after
@@ -611,8 +611,6 @@ struct log_t{
 later; this is advanced when a flush
 operation is completed to all the log
 groups */
-volatile boolis_extending;/*!< this is set to true during extend
-the log buffer size */
 lsn_twrite_lsn;/*!< last written lsn */
 lsn_tcurrent_flush_lsn;/*!< end lsn for the current running
 write + flush operation */

storage/innobase/log/log0log.cc

@@ -161,87 +161,42 @@ log_buf_pool_get_oldest_modification(void)
 @param[in]	len	requested minimum size in bytes */
 void log_buffer_extend(ulong len)
 {
-byte	tmp_buf[OS_FILE_LOG_BLOCK_SIZE];
+const ulong new_buf_size = ut_calc_align(len, srv_page_size);
+byte* new_buf = static_cast<byte*>(
+ut_malloc_dontdump(new_buf_size * 2));
+TRASH_ALLOC(new_buf, new_buf_size * 2);
 
-log_mutex_enter_all();
-
-while (log_sys.is_extending) {
-/* Another thread is trying to extend already.
-Needs to wait for. */
-log_mutex_exit_all();
-
-log_buffer_flush_to_disk();
-
-log_mutex_enter_all();
-
-if (srv_log_buffer_size > len) {
-/* Already extended enough by the others */
-log_mutex_exit_all();
-return;
-}
-}
-
-if (len >= srv_log_buffer_size / 2) {
-DBUG_EXECUTE_IF("ib_log_buffer_is_short_crash",
-DBUG_SUICIDE(););
-
-/* log_buffer is too small. try to extend instead of crash. */
-ib::warn() << "The redo log transaction size " << len <<
-" exceeds innodb_log_buffer_size="
-<< srv_log_buffer_size << " / 2). Trying to extend it.";
-}
-
-log_sys.is_extending = true;
-
-while ((log_sys.buf_free ^ log_sys.buf_next_to_write)
- & (OS_FILE_LOG_BLOCK_SIZE - 1)) {
-/* Buffer might have >1 blocks to write still. */
-log_mutex_exit_all();
-
-log_buffer_flush_to_disk();
-
-log_mutex_enter_all();
-}
-
-ulong move_start = ut_2pow_round(log_sys.buf_free,
- ulong(OS_FILE_LOG_BLOCK_SIZE));
-ulong move_end = log_sys.buf_free;
-
-/* store the last log block in buffer */
-ut_memcpy(tmp_buf, log_sys.buf + move_start,
- move_end - move_start);
-
-log_sys.buf_free -= move_start;
-log_sys.buf_next_to_write -= move_start;
+log_mutex_enter();
 
-/* free previous after getting the right address */
-if (!log_sys.first_in_use) {
-log_sys.buf -= srv_log_buffer_size;
+if (len <= srv_log_buffer_size) {
+/* Already extended enough by the others */
+log_mutex_exit();
+ut_free_dodump(new_buf, new_buf_size * 2);
+return;
 }
-ut_free_dodump(log_sys.buf, srv_log_buffer_size * 2);
-
-/* reallocate log buffer */
-srv_log_buffer_size = len;
 
-log_sys.buf = static_cast<byte*>(
-ut_malloc_dontdump(srv_log_buffer_size * 2));
-TRASH_ALLOC(log_sys.buf, srv_log_buffer_size * 2);
+ib::warn() << "The redo log transaction size " << len <<
+" exceeds innodb_log_buffer_size="
+<< srv_log_buffer_size << " / 2). Trying to extend it.";
 
+const byte* old_buf_begin = log_sys.buf;
+const ulong old_buf_size = srv_log_buffer_size;
+byte* old_buf = log_sys.first_in_use
+? log_sys.buf : log_sys.buf - old_buf_size;
+srv_log_buffer_size = new_buf_size;
+log_sys.buf = new_buf;
 log_sys.first_in_use = true;
+memcpy(log_sys.buf, old_buf_begin, log_sys.buf_free);
 
-log_sys.max_buf_free = srv_log_buffer_size / LOG_BUF_FLUSH_RATIO
+log_sys.max_buf_free = new_buf_size / LOG_BUF_FLUSH_RATIO
 - LOG_BUF_FLUSH_MARGIN;
 
-/* restore the last log block */
-ut_memcpy(log_sys.buf, tmp_buf, move_end - move_start);
-
-ut_ad(log_sys.is_extending);
-log_sys.is_extending = false;
+log_mutex_exit();
 
-log_mutex_exit_all();
+ut_free_dodump(old_buf, old_buf_size);
 
 ib::info() << "innodb_log_buffer_size was extended to "
-<< srv_log_buffer_size << ".";
+<< new_buf_size << ".";
 }
 
 /** Calculate actual length in redo buffer and file including
@@ -350,20 +305,6 @@ log_reserve_and_open(
 loop:
 ut_ad(log_mutex_own());
 
-if (log_sys.is_extending) {
-log_mutex_exit();
-
-/* Log buffer size is extending. Writing up to the next block
-should wait for the extending finished. */
-
-os_thread_sleep(100000);
-
-ut_ad(++count < 50);
-
-log_mutex_enter();
-goto loop;
-}
-
 /* Calculate an upper limit for the space the string may take in the
 log buffer */
 
@@ -619,7 +560,6 @@ void log_t::create()
  last_printout_time= time(NULL);
 
  buf_next_to_write= 0;
- is_extending= false;
  write_lsn= lsn;
  flushed_to_disk_lsn= 0;
  n_pending_flushes= 0;