All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] fs: shave 8 bytes off of struct inode
@ 2018-06-12 11:11 Amir Goldstein
  2018-06-12 14:24 ` Jan Kara
  2018-07-02  5:14 ` [lkp-robot] [fs] 5c6de586e8: vm-scalability.throughput +12.4% improvement kernel test robot
  0 siblings, 2 replies; 8+ messages in thread
From: Amir Goldstein @ 2018-06-12 11:11 UTC (permalink / raw)
  To: Linus Torvalds; +Cc: Jan Kara, Al Viro, linux-fsdevel

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
---

Linus,

I tried to find some space to cram i_generation in case
I get rid of i_fsnotify_mask, but stumbled on a possible
"lossless compression".

Any caveats with this change?

Thanks,
Amir.

 include/linux/fs.h | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 760d8da1b6c7..6d0489613dc1 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -274,6 +274,7 @@ struct writeback_control;
 
 /*
  * Write life time hint values.
+ * Stored in struct inode as u8.
  */
 enum rw_hint {
 	WRITE_LIFE_NOT_SET	= 0,
@@ -607,8 +608,8 @@ struct inode {
 	struct timespec		i_ctime;
 	spinlock_t		i_lock;	/* i_blocks, i_bytes, maybe i_size */
 	unsigned short          i_bytes;
-	unsigned int		i_blkbits;
-	enum rw_hint		i_write_hint;
+	u8			i_blkbits;
+	u8			i_write_hint;
 	blkcnt_t		i_blocks;
 
 #ifdef __NEED_I_SIZE_ORDERED
-- 
2.7.4

^ permalink raw reply related	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2018-07-02  5:14 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2018-06-12 11:11 [PATCH] fs: shave 8 bytes off of struct inode Amir Goldstein
2018-06-12 14:24 ` Jan Kara
2018-06-12 14:28   ` Matthew Wilcox
2018-06-12 14:38   ` Amir Goldstein
2018-06-12 16:31     ` Linus Torvalds
2018-06-12 17:50       ` Amir Goldstein
2018-06-12 17:57         ` Linus Torvalds
2018-07-02  5:14 ` [lkp-robot] [fs] 5c6de586e8: vm-scalability.throughput +12.4% improvement kernel test robot

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.