Commit 774a6a11 authored by Yan, Zheng's avatar Yan, Zheng Committed by Ilya Dryomov
Browse files

ceph: reduce i_nr_by_mode array size 



Track usage count for individual fmode bit. This can reduce the
array size by half.

Signed-off-by: default avatarYan, Zheng <zyan@redhat.com>
parent a22bd5ff

fs/ceph/caps.c

+31 −14
Original line number Diff line number Diff line
@@ -849,12 +849,14 @@ int __ceph_caps_used(struct ceph_inode_info *ci) 
 */

int __ceph_caps_file_wanted(struct ceph_inode_info *ci)

{

	int want = 0;

	int mode;

	for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)

		if (ci->i_nr_by_mode[mode])

			want |= ceph_caps_for_mode(mode);

	return want;

	int i, bits = 0;

	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {

		if (ci->i_nr_by_mode[i])

			bits |= 1 << i;

	}

	if (bits == 0)

		return 0;

	return ceph_caps_for_mode(bits >> 1);

}



/*
@@ -3682,6 +3684,16 @@ void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc) 
	dout("flush_dirty_caps done\n");

}



void __ceph_get_fmode(struct ceph_inode_info *ci, int fmode)

{

	int i;

	int bits = (fmode << 1) | 1;

	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {

		if (bits & (1 << i))

			ci->i_nr_by_mode[i]++;

	}

}



/*

 * Drop open file reference.  If we were the last open file,

 * we may need to release capabilities to the MDS (or schedule
@@ -3689,15 +3701,20 @@ void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc) 
 */

void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)

{

	struct inode *inode = &ci->vfs_inode;

	int last = 0;



	int i, last = 0;

	int bits = (fmode << 1) | 1;

	spin_lock(&ci->i_ceph_lock);

	dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,

	     ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);

	BUG_ON(ci->i_nr_by_mode[fmode] == 0);

	if (--ci->i_nr_by_mode[fmode] == 0)

	for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {

		if (bits & (1 << i)) {

			BUG_ON(ci->i_nr_by_mode[i] == 0);

			if (--ci->i_nr_by_mode[i] == 0)

				last++;

		}

	}

	dout("put_fmode %p fmode %d {%d,%d,%d,%d}\n",

	     &ci->vfs_inode, fmode,

	     ci->i_nr_by_mode[0], ci->i_nr_by_mode[1],

	     ci->i_nr_by_mode[2], ci->i_nr_by_mode[3]);

	spin_unlock(&ci->i_ceph_lock);



	if (last && ci->i_vino.snap == CEPH_NOSNAP)

fs/ceph/inode.c

+1 −1
Original line number Diff line number Diff line
@@ -477,7 +477,7 @@ struct inode *ceph_alloc_inode(struct super_block *sb) 
	ci->i_head_snapc = NULL;

	ci->i_snap_caps = 0;



	for (i = 0; i < CEPH_FILE_MODE_NUM; i++)

	for (i = 0; i < CEPH_FILE_MODE_BITS; i++)

		ci->i_nr_by_mode[i] = 0;



	mutex_init(&ci->i_truncate_mutex);

fs/ceph/ioctl.c

+1 −2
Original line number Diff line number Diff line
@@ -250,9 +250,8 @@ static long ceph_ioctl_lazyio(struct file *file) 


	if ((fi->fmode & CEPH_FILE_MODE_LAZY) == 0) {

		spin_lock(&ci->i_ceph_lock);

		ci->i_nr_by_mode[fi->fmode]--;

		fi->fmode |= CEPH_FILE_MODE_LAZY;

		ci->i_nr_by_mode[fi->fmode]++;

		ci->i_nr_by_mode[ffs(CEPH_FILE_MODE_LAZY)]++;

		spin_unlock(&ci->i_ceph_lock);

		dout("ioctl_layzio: file %p marked lazy\n", file);

fs/ceph/super.h

+2 −5
Original line number Diff line number Diff line
@@ -321,7 +321,7 @@ struct ceph_inode_info { 
						    dirty|flushing caps */

	unsigned i_snap_caps;           /* cap bits for snapped files */



	int i_nr_by_mode[CEPH_FILE_MODE_NUM];  /* open file counts */

	int i_nr_by_mode[CEPH_FILE_MODE_BITS];  /* open file counts */



	struct mutex i_truncate_mutex;

	u32 i_truncate_seq;        /* last truncate to smaller size */
@@ -906,10 +906,7 @@ extern int ceph_get_caps(struct ceph_inode_info *ci, int need, int want, 
			 loff_t endoff, int *got, struct page **pinned_page);



/* for counting open files by mode */

static inline void __ceph_get_fmode(struct ceph_inode_info *ci, int mode)

{

	ci->i_nr_by_mode[mode]++;

}

extern void __ceph_get_fmode(struct ceph_inode_info *ci, int mode);

extern void ceph_put_fmode(struct ceph_inode_info *ci, int mode);



/* addr.c */

include/linux/ceph/ceph_fs.h

+1 −1
Original line number Diff line number Diff line
@@ -525,7 +525,7 @@ struct ceph_filelock { 
#define CEPH_FILE_MODE_WR         2

#define CEPH_FILE_MODE_RDWR       3  /* RD | WR */

#define CEPH_FILE_MODE_LAZY       4  /* lazy io */

#define CEPH_FILE_MODE_NUM        8  /* bc these are bit fields.. mostly */

#define CEPH_FILE_MODE_BITS       4



int ceph_flags_to_mode(int flags);