File early-sync-shutdown.patch of Package systemd
From c65eb8365344eeb72ee2c0b333ab54d925263b3f Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Fri, 25 Jan 2013 22:33:33 +0100
Subject: [PATCH] shutdown: issue a sync() as soon as shutdown.target is queued
---
Makefile.am | 7 ++++--
src/core/job.c | 26 ++++++++++++++++++++
src/core/job.h | 2 ++
src/core/sync.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++++
src/core/sync.h | 24 +++++++++++++++++++
src/core/transaction.c | 1 +
6 files changed, 123 insertions(+), 2 deletions(-)
create mode 100644 src/core/sync.c
create mode 100644 src/core/sync.h
Index: systemd-195/Makefile.am
===================================================================
--- systemd-195.orig/Makefile.am
+++ systemd-195/Makefile.am
@@ -1038,7 +1038,9 @@ libsystemd_core_la_SOURCES = \
src/core/syscall-list.c \
src/core/syscall-list.h \
src/core/audit-fd.c \
- src/core/audit-fd.h
+ src/core/audit-fd.h \
+ src/core/sync.c \
+ src/core/sync.h
nodist_libsystemd_core_la_SOURCES = \
src/core/load-fragment-gperf.c \
@@ -1052,7 +1054,8 @@ libsystemd_core_la_CFLAGS = \
$(LIBWRAP_CFLAGS) \
$(PAM_CFLAGS) \
$(AUDIT_CFLAGS) \
- $(KMOD_CFLAGS)
+ $(KMOD_CFLAGS) \
+ -pthread
libsystemd_core_la_LIBADD = \
libsystemd-capability.la \
Index: systemd-195/src/core/job.c
===================================================================
--- systemd-195.orig/src/core/job.c
+++ systemd-195/src/core/job.c
@@ -34,6 +34,9 @@
#include "load-dropin.h"
#include "log.h"
#include "dbus-job.h"
+#include "special.h"
+#include "sync.h"
+#include "virt.h"
JobBusClient* job_bus_client_new(DBusConnection *connection, const char *name) {
JobBusClient *cl;
@@ -1045,6 +1048,29 @@ int job_coldplug(Job *j) {
return 0;
}
+void job_shutdown_magic(Job *j) {
+ assert(j);
+
+ /* The shutdown target gets some special treatment here: we
+ * tell the kernel to begin with flushing its disk caches, to
+ * optimize shutdown time a bit. Ideally we wouldn't hardcode
+ * this magic into PID 1. However all other processes aren't
+ * options either since they'd exit much sooner than PID 1 and
+ * asynchronous sync() would cause their exit to be
+ * delayed. */
+
+ if (!unit_has_name(j->unit, SPECIAL_SHUTDOWN_TARGET))
+ return;
+
+ if (j->type != JOB_START)
+ return;
+
+ if (detect_container(NULL) > 0)
+ return;
+
+ asynchronous_sync();
+}
+
static const char* const job_state_table[_JOB_STATE_MAX] = {
[JOB_WAITING] = "waiting",
[JOB_RUNNING] = "running"
Index: systemd-195/src/core/job.h
===================================================================
--- systemd-195.orig/src/core/job.h
+++ systemd-195/src/core/job.h
@@ -217,6 +217,8 @@ int job_finish_and_invalidate(Job *j, Jo
char *job_dbus_path(Job *j);
+void job_shutdown_magic(Job *j);
+
const char* job_type_to_string(JobType t);
JobType job_type_from_string(const char *s);
Index: systemd-195/src/core/sync.c
===================================================================
--- /dev/null
+++ systemd-195/src/core/sync.c
@@ -0,0 +1,65 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+ This file is part of systemd.
+
+ Copyright 2013 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <pthread.h>
+#include <unistd.h>
+
+#include "sync.h"
+
+static void *sync_thread(void *p) {
+ sync();
+ return NULL;
+}
+
+int asynchronous_sync(void) {
+ pthread_attr_t a;
+ pthread_t t;
+ int r;
+
+ /* It kinda sucks that we have to resort to threads to
+ * implement an asynchronous sync(), but well, such is
+ * life.
+ *
+ * Note that issuing this command right before exiting a
+ * process will cause the process to wait for the sync() to
+ * complete. This function hence is nicely asynchronous really
+ * only in long running processes. */
+
+ r = pthread_attr_init(&a);
+ if (r != 0)
+ return -r;
+
+ r = pthread_attr_setdetachstate(&a, PTHREAD_CREATE_DETACHED);
+ if (r != 0) {
+ r = -r;
+ goto finish;
+ }
+
+ r = pthread_create(&t, &a, sync_thread, NULL);
+ if (r != 0) {
+ r = -r;
+ goto finish;
+ }
+
+finish:
+ pthread_attr_destroy(&a);
+ return r;
+}
Index: systemd-195/src/core/sync.h
===================================================================
--- /dev/null
+++ systemd-195/src/core/sync.h
@@ -0,0 +1,24 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+#pragma once
+
+/***
+ This file is part of systemd.
+
+ Copyright 2013 Lennart Poettering
+
+ systemd is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published by
+ the Free Software Foundation; either version 2.1 of the License, or
+ (at your option) any later version.
+
+ systemd 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
+ Lesser General Public License for more details.
+
+ You should have received a copy of the GNU Lesser General Public License
+ along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+int asynchronous_sync(void);
Index: systemd-195/src/core/transaction.c
===================================================================
--- systemd-195.orig/src/core/transaction.c
+++ systemd-195/src/core/transaction.c
@@ -592,6 +592,7 @@ static int transaction_apply(Transaction
job_add_to_run_queue(j);
job_add_to_dbus_queue(j);
job_start_timer(j);
+ job_shutdown_magic(j);
}
return 0;
