MDEV-5247: DB locked up at btr0cur.c line 568. There is inconsistent and non logical usage of have_LRU_mutex and incorrect value on ha_innodb.cc when buf_LRU_free_block is called. Additionally, for future long semaphore wait cases added a new configuration variable innodb_use_stacktrace. If this variable is true a signal handler for SIGUSR2 is installed when InnoDB server starts and when a long semaphore wait is detected at sync/sync0array.c we send SIGUSR2 signal to waiting thread and thread that has acuired RW-latch. For both threads a full stacktrace is produced as well as its is possible.

1 files changed, 42 insertions, 0 deletions

diff --git a/storage/xtradb/include/os0stacktrace.h b/storage/xtradb/include/os0stacktrace.h
new file mode 100644
index 00000000000..15921a11be0
--- /dev/null
+++ b/storage/xtradb/include/os0stacktrace.h
@@ -0,0 +1,42 @@
+/*****************************************************************************
+
+Copyright (C) 2013 SkySQL Ab. All Rights Reserved.
+
+
+This program is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free Software
+Foundation; version 2 of the License.
+
+This program is distributed in the hope that it will be useful, but WITHOUT
+ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+this program; if not, write to the Free Software Foundation, Inc.,
+51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+*****************************************************************************/
+
+#ifndef os0stacktrace_h
+#define os0stacktrace_h
+
+#ifndef __WIN__
+#include <execinfo.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+/***************************************************************//**
+Prints stacktrace for this thread.
+*/
+void
+os_stacktrace_print(
+/*================*/
+	int        sig_num,  /*!< in: signal number */
+	siginfo_t* info,     /*!< in: signal information */
+	void*      ucontext);/*!< in: signal context */
+
+#endif /* ! __WIN__ */
+#endif /* os0stacktrace.h */