X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=include%2Flttng%2Fust-sigbus.h;fp=include%2Flttng%2Fust-sigbus.h;h=7cdc1c1f7e4541cbef2709b5bc14e4f124af4d17;hb=63b3205fe76018eb5d7656b94b54c9b662ae208f;hp=0000000000000000000000000000000000000000;hpb=a5d437c5f61a1b089e3ea76e4d124683b3aa456e;p=lttng-ust.git

diff --git a/include/lttng/ust-sigbus.h b/include/lttng/ust-sigbus.h
new file mode 100644
index 00000000..7cdc1c1f
--- /dev/null
+++ b/include/lttng/ust-sigbus.h
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2020 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * 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 only.
+ *
+ * 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 Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef _LTTNG_UST_SIGBUS_H
+#define _LTTNG_UST_SIGBUS_H
+
+#include <urcu/list.h>
+#include <setjmp.h>
+
+struct lttng_ust_sigbus_range {
+	void *start;	/* inclusive */
+	void *end;	/* exclusive */
+	struct cds_list_head node;
+};
+
+struct lttng_ust_sigbus_state {
+	int jmp_ready;
+	struct cds_list_head head;	/* struct lttng_ust_sigbus_range */
+	sigjmp_buf sj_env;
+};
+
+/*
+ * Define the lttng_ust_sigbus_state TLS variable as initial-exec model
+ * to allow using it from the SIGBUS signal handler. This variable must
+ * be defined by the executable using DEFINE_LTTNG_UST_SIGBUS_STATE()
+ * rather than internally within liblttng-ust-ctl.so to ensure we don't
+ * contribute to reach glibc limits of pre-allocated TLS IE model space
+ * for shared objects.
+ */
+#define DEFINE_LTTNG_UST_SIGBUS_STATE()	\
+	__thread __attribute__((tls_model("initial-exec"))) struct lttng_ust_sigbus_state lttng_ust_sigbus_state
+
+extern __thread __attribute__((tls_model("initial-exec"))) struct lttng_ust_sigbus_state lttng_ust_sigbus_state;
+
+#endif /* _LTTNG_UST_SIGBUS_H */