[PATCH 11/89] sched/headers, delayacct: Move the 'struct task_delay_info' definition from to

Ingo Molnar
2017-02-06T13:56:12Z

The 'struct task_delay_info' definition does not have to be in sched.h,
because task_struct only has a pointer to it.

So move it to <linux/delayacct.h> to reduce the size of <linux/sched.h>.

As an additional improvement make the type defined but empty in the
!CONFIG_TASK_DELAY_ACCT case - to eliminate the ugly #ifdef
around the task_struct field as well.

Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
include/linux/delayacct.h | 38 ++++++++++++++++++++++++++++++++++++--
include/linux/sched.h | 37 ++-----------------------------------
2 files changed, 38 insertions(+), 37 deletions(-)

diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h
index 00e60f79a9cc..a2192de5d428 100644
--- a/include/linux/delayacct.h
+++ b/include/linux/delayacct.h
@@ -18,8 +18,6 @@
#define _LINUX_DELAYACCT_H

#include <uapi/linux/taskstats.h>
-#include <linux/sched.h>
-#include <linux/slab.h>

/*
* Per-task flags relevant to delay accounting
@@ -29,8 +27,44 @@
#define DELAYACCT_PF_SWAPIN 0x00000001 /* I am doing a swapin */
#define DELAYACCT_PF_BLKIO 0x00000002 /* I am waiting on IO */

+struct task_delay_info {
#ifdef CONFIG_TASK_DELAY_ACCT
+ spinlock_t lock;
+ unsigned int flags; /* Private per-task flags */
+
+ /* For each stat XXX, add following, aligned appropriately
+ *
+ * struct timespec XXX_start, XXX_end;
+ * u64 XXX_delay;
+ * u32 XXX_count;
+ *
+ * Atomicity of updates to XXX_delay, XXX_count protected by
+ * single lock above (split into XXX_lock if contention is an issue).
+ */
+
+ /*
+ * XXX_count is incremented on every XXX operation, the delay
+ * associated with the operation is added to XXX_delay.
+ * XXX_delay contains the accumulated delay time in nanoseconds.
+ */
+ u64 blkio_start; /* Shared by blkio, swapin */
+ u64 blkio_delay; /* wait for sync block io completion */
+ u64 swapin_delay; /* wait for swapin block io completion */
+ u32 blkio_count; /* total count of the number of sync block */
+ /* io operations performed */
+ u32 swapin_count; /* total count of the number of swapin block */
+ /* io operations performed */
+
+ u64 freepages_start;
+ u64 freepages_delay; /* wait for memory reclaim */
+ u32 freepages_count; /* total count of memory reclaim */
+#endif
+};

+#include <linux/sched.h>
+#include <linux/slab.h>
+
+#ifdef CONFIG_TASK_DELAY_ACCT
extern int delayacct_on; /* Delay accounting turned on/off */
extern struct kmem_cache *delayacct_cache;
extern void delayacct_init(void);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 4b49d159f4d5..15971b1e3f57 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -901,39 +901,7 @@ struct sched_info {
};
#endif /* CONFIG_SCHED_INFO */

-#ifdef CONFIG_TASK_DELAY_ACCT
-struct task_delay_info {
- spinlock_t lock;
- unsigned int flags; /* Private per-task flags */
-
- /* For each stat XXX, add following, aligned appropriately
- *
- * struct timespec XXX_start, XXX_end;
- * u64 XXX_delay;
- * u32 XXX_count;
- *
- * Atomicity of updates to XXX_delay, XXX_count protected by
- * single lock above (split into XXX_lock if contention is an issue).
- */
-
- /*
- * XXX_count is incremented on every XXX operation, the delay
- * associated with the operation is added to XXX_delay.
- * XXX_delay contains the accumulated delay time in nanoseconds.
- */
- u64 blkio_start; /* Shared by blkio, swapin */
- u64 blkio_delay; /* wait for sync block io completion */
- u64 swapin_delay; /* wait for swapin block io completion */
- u32 blkio_count; /* total count of the number of sync block */
- /* io operations performed */
- u32 swapin_count; /* total count of the number of swapin block */
- /* io operations performed */
-
- u64 freepages_start;
- u64 freepages_delay; /* wait for memory reclaim */
- u32 freepages_count; /* total count of memory reclaim */
-};
-#endif /* CONFIG_TASK_DELAY_ACCT */
+struct task_delay_info;

static inline int sched_info_on(void)
{
@@ -1615,9 +1583,8 @@ struct task_struct {

struct page_frag task_frag;

-#ifdef CONFIG_TASK_DELAY_ACCT
struct task_delay_info *delays;
-#endif
+
#ifdef CONFIG_FAULT_INJECTION
int make_it_fail;
#endif
--
2.7.4