From 2385aec22313bde33dd023897e6d700a386506b5 Mon Sep 17 00:00:00 2001
From: Vladimir Davydov <vdavydov.dev@gmail.com>
Date: Mon, 4 Mar 2019 14:01:51 +0300
Subject: [PATCH] engine: add switch_to_ro callback
We will use this callback to abort rw transactions in Vinyl when an
instance is switch to read-only mode.
Needed for #4016
---
src/box/blackhole.c | 1 +
src/box/box.cc | 7 +++++++
src/box/engine.c | 14 ++++++++++++++
src/box/engine.h | 13 +++++++++++++
src/box/memtx_engine.c | 1 +
src/box/sysview.c | 1 +
src/box/vinyl.c | 1 +
7 files changed, 38 insertions(+)
diff --git a/src/box/blackhole.c b/src/box/blackhole.c
index 249eb678ad..95064e1faf 100644
--- a/src/box/blackhole.c
+++ b/src/box/blackhole.c
@@ -184,6 +184,7 @@ static const struct engine_vtab blackhole_engine_vtab = {
/* .commit = */ generic_engine_commit,
/* .rollback_statement = */ generic_engine_rollback_statement,
/* .rollback = */ generic_engine_rollback,
+ /* .switch_to_ro = */ generic_engine_switch_to_ro,
/* .bootstrap = */ generic_engine_bootstrap,
/* .begin_initial_recovery = */ generic_engine_begin_initial_recovery,
/* .begin_final_recovery = */ generic_engine_begin_final_recovery,
diff --git a/src/box/box.cc b/src/box/box.cc
index a62595421c..fb8968525e 100644
--- a/src/box/box.cc
+++ b/src/box/box.cc
@@ -222,6 +222,11 @@ process_nop(struct request *request)
void
box_set_ro(bool ro)
{
+ if (ro == is_ro)
+ return; /* nothing to do */
+ if (ro)
+ engine_switch_to_ro();
+
is_ro = ro;
fiber_cond_broadcast(&ro_cond);
}
@@ -252,6 +257,8 @@ box_set_orphan(bool orphan)
{
if (is_orphan == orphan)
return; /* nothing to do */
+ if (orphan)
+ engine_switch_to_ro();
is_orphan = orphan;
fiber_cond_broadcast(&ro_cond);
diff --git a/src/box/engine.c b/src/box/engine.c
index d0a08f5cdb..a52d0ed1ba 100644
--- a/src/box/engine.c
+++ b/src/box/engine.c
@@ -65,6 +65,14 @@ engine_shutdown(void)
}
}
+void
+engine_switch_to_ro(void)
+{
+ struct engine *engine;
+ engine_foreach(engine)
+ engine->vtab->switch_to_ro(engine);
+}
+
int
engine_bootstrap(void)
{
@@ -253,6 +261,12 @@ generic_engine_rollback(struct engine *engine, struct txn *txn)
(void)txn;
}
+void
+generic_engine_switch_to_ro(struct engine *engine)
+{
+ (void)engine;
+}
+
int
generic_engine_bootstrap(struct engine *engine)
{
diff --git a/src/box/engine.h b/src/box/engine.h
index a6949d288b..a302b3bca9 100644
--- a/src/box/engine.h
+++ b/src/box/engine.h
@@ -112,6 +112,12 @@ struct engine_vtab {
* Roll back and end the transaction in the engine.
*/
void (*rollback)(struct engine *, struct txn *);
+ /**
+ * Notify the engine that the instance is about to switch
+ * to read-only mode. The engine is supposed to abort all
+ * active rw transactions when this method is called.
+ */
+ void (*switch_to_ro)(struct engine *);
/**
* Bootstrap an empty data directory
*/
@@ -292,6 +298,12 @@ engine_check_space_def(struct engine *engine, struct space_def *def)
void
engine_shutdown(void);
+/**
+ * Called before switching the instance to read-only mode.
+ */
+void
+engine_switch_to_ro(void);
+
/**
* Initialize an empty data directory
*/
@@ -361,6 +373,7 @@ void generic_engine_commit(struct engine *, struct txn *);
void generic_engine_rollback_statement(struct engine *, struct txn *,
struct txn_stmt *);
void generic_engine_rollback(struct engine *, struct txn *);
+void generic_engine_switch_to_ro(struct engine *);
int generic_engine_bootstrap(struct engine *);
int generic_engine_begin_initial_recovery(struct engine *,
const struct vclock *);
diff --git a/src/box/memtx_engine.c b/src/box/memtx_engine.c
index 049a7f7d7f..d468d1cd84 100644
--- a/src/box/memtx_engine.c
+++ b/src/box/memtx_engine.c
@@ -936,6 +936,7 @@ static const struct engine_vtab memtx_engine_vtab = {
/* .commit = */ generic_engine_commit,
/* .rollback_statement = */ memtx_engine_rollback_statement,
/* .rollback = */ memtx_engine_rollback,
+ /* .switch_to_ro = */ generic_engine_switch_to_ro,
/* .bootstrap = */ memtx_engine_bootstrap,
/* .begin_initial_recovery = */ memtx_engine_begin_initial_recovery,
/* .begin_final_recovery = */ memtx_engine_begin_final_recovery,
diff --git a/src/box/sysview.c b/src/box/sysview.c
index 29de430937..63b669d074 100644
--- a/src/box/sysview.c
+++ b/src/box/sysview.c
@@ -534,6 +534,7 @@ static const struct engine_vtab sysview_engine_vtab = {
/* .commit = */ generic_engine_commit,
/* .rollback_statement = */ generic_engine_rollback_statement,
/* .rollback = */ generic_engine_rollback,
+ /* .switch_to_ro = */ generic_engine_switch_to_ro,
/* .bootstrap = */ generic_engine_bootstrap,
/* .begin_initial_recovery = */ generic_engine_begin_initial_recovery,
/* .begin_final_recovery = */ generic_engine_begin_final_recovery,
diff --git a/src/box/vinyl.c b/src/box/vinyl.c
index 87b9eefacf..c8b02eb874 100644
--- a/src/box/vinyl.c
+++ b/src/box/vinyl.c
@@ -4463,6 +4463,7 @@ static const struct engine_vtab vinyl_engine_vtab = {
/* .commit = */ vinyl_engine_commit,
/* .rollback_statement = */ vinyl_engine_rollback_statement,
/* .rollback = */ vinyl_engine_rollback,
+ /* .switch_to_ro = */ generic_engine_switch_to_ro,
/* .bootstrap = */ vinyl_engine_bootstrap,
/* .begin_initial_recovery = */ vinyl_engine_begin_initial_recovery,
/* .begin_final_recovery = */ vinyl_engine_begin_final_recovery,
--
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