task_struct: make journal_info conditional

journal_info in task_struct is used in journaling file system only.  So
introduce CONFIG_FS_JOURNAL_INFO and make it conditional.

Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: "Theodore Ts'o" <tytso@mit.edu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

2 files changed, 9 insertions, 1 deletions

diff --git a/include/linux/init_task.h b/include/linux/init_task.h
index 8d10aa7fd4c9..8ed0abf06f89 100644
--- a/include/linux/init_task.h
+++ b/include/linux/init_task.h
@@ -111,6 +111,12 @@ extern struct cred init_cred;
 # define INIT_PERF_EVENTS(tsk)
 #endif
 
+#ifdef CONFIG_FS_JOURNAL_INFO
+#define INIT_JOURNAL_INFO       .journal_info = NULL,
+#else
+#define INIT_JOURNAL_INFO
+#endif
+
 /*
  *  INIT_TASK is used to set up the first task table, touch at
  * your own risk!. Base=0, limit=0x1fffff (=2MB)
@@ -162,7 +168,6 @@ extern struct cred init_cred;
                 .signal = {{0}}},                                       \
         .blocked        = {{0}},                                        \
         .alloc_lock     = __SPIN_LOCK_UNLOCKED(tsk.alloc_lock),         \
-        .journal_info   = NULL,                                         \
         .cpu_timers     = INIT_CPU_TIMERS(tsk.cpu_timers),              \
         .fs_excl        = ATOMIC_INIT(0),                               \
         .pi_lock        = __SPIN_LOCK_UNLOCKED(tsk.pi_lock),            \
@@ -173,6 +178,7 @@ extern struct cred init_cred;
                 [PIDTYPE_SID]  = INIT_PID_LINK(PIDTYPE_SID),            \
         },                                                              \
         .dirties = INIT_PROP_LOCAL_SINGLE(dirties),                     \
+        INIT_JOURNAL_INFO                                               \
         INIT_IDS                                                        \
         INIT_PERF_EVENTS(tsk)                                           \
         INIT_TRACE_IRQFLAGS                                             \
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 294eb2f80144..7d388494f45d 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1446,8 +1446,10 @@ struct task_struct {
         gfp_t lockdep_reclaim_gfp;
 #endif
 
+#ifdef CONFIG_FS_JOURNAL_INFO
 /* journalling filesystem info */
         void *journal_info;
+#endif
 
 /* stacked block device info */
         struct bio *bio_list, **bio_tail;