Commit 1ad38c43 authored by Steven Whitehouse's avatar Steven Whitehouse
Browse files

[GFS2] Clean up gfs2_trans_add_revoke() 



The following alters gfs2_trans_add_revoke() to take a struct
gfs2_bufdata as an argument. This eliminates the memory allocation which
was previously required by making use of the already existing struct
gfs2_bufdata. It makes some sanity checks to ensure that the
gfs2_bufdata has been removed from all the lists before its recycled as
a revoke structure. This saves one memory allocation and one free per
revoke structure.

Also as a result, and to simplify the locking, since there is no longer
any blocking code in gfs2_trans_add_revoke() we must hold the log lock
whenever this function is called. This reduces the amount of times we
take and unlock the log lock.

Signed-off-by: default avatarSteven Whitehouse <swhiteho@redhat.com>
parent 0820ab51

fs/gfs2/glops.c

+5 −9
Original line number Diff line number Diff line
@@ -41,7 +41,6 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl) 
	struct list_head *head = &gl->gl_ail_list;

	struct gfs2_bufdata *bd;

	struct buffer_head *bh;

	u64 blkno;

	int error;



	blocks = atomic_read(&gl->gl_ail_count);
@@ -57,15 +56,12 @@ static void gfs2_ail_empty_gl(struct gfs2_glock *gl) 
		bd = list_entry(head->next, struct gfs2_bufdata,

				bd_ail_gl_list);

		bh = bd->bd_bh;

		blkno = bh->b_blocknr;

		gfs2_assert_withdraw(sdp, !buffer_busy(bh));



		gfs2_remove_from_ail(NULL, bd);

		gfs2_log_unlock(sdp);



		gfs2_trans_add_revoke(sdp, blkno);



		gfs2_log_lock(sdp);

		bd->bd_bh = NULL;

		bh->b_private = NULL;

		bd->bd_blkno = bh->b_blocknr;

		gfs2_assert_withdraw(sdp, !buffer_busy(bh));

		gfs2_trans_add_revoke(sdp, bd);

	}

	gfs2_assert_withdraw(sdp, !atomic_read(&gl->gl_ail_count));

	gfs2_log_unlock(sdp);

fs/gfs2/log.c

+2 −2
Original line number Diff line number Diff line
@@ -71,8 +71,8 @@ unsigned int gfs2_struct2blk(struct gfs2_sbd *sdp, unsigned int nstruct, 
void gfs2_remove_from_ail(struct address_space *mapping, struct gfs2_bufdata *bd)

{

	bd->bd_ail = NULL;

	list_del(&bd->bd_ail_st_list);

	list_del(&bd->bd_ail_gl_list);

	list_del_init(&bd->bd_ail_st_list);

	list_del_init(&bd->bd_ail_gl_list);

	atomic_dec(&bd->bd_gl->gl_ail_count);

	if (mapping)

		gfs2_meta_cache_flush(GFS2_I(mapping->host));

fs/gfs2/lops.c

+0 −3
Original line number Diff line number Diff line
@@ -343,11 +343,8 @@ static void revoke_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) 
	tr = current->journal_info;

	tr->tr_touched = 1;

	tr->tr_num_revoke++;



	gfs2_log_lock(sdp);

	sdp->sd_log_num_revoke++;

	list_add(&le->le_list, &sdp->sd_log_le_revoke);

	gfs2_log_unlock(sdp);

}



static void revoke_lo_before_commit(struct gfs2_sbd *sdp)

fs/gfs2/meta_io.c

+12 −23
Original line number Diff line number Diff line
@@ -313,42 +313,31 @@ void gfs2_meta_wipe(struct gfs2_inode *ip, u64 bstart, u32 blen) 
	while (blen) {

		bh = getbuf(ip->i_gl, bstart, NO_CREATE);

		if (bh) {

			struct gfs2_bufdata *bd = bh->b_private;

			struct gfs2_bufdata *bd;



			lock_buffer(bh);

			gfs2_log_lock(sdp);

			bd = bh->b_private;

			if (test_clear_buffer_pinned(bh)) {

				struct gfs2_trans *tr = current->journal_info;

				struct gfs2_inode *bh_ip =

					GFS2_I(bh->b_page->mapping->host);



				gfs2_log_lock(sdp);

				list_del_init(&bd->bd_le.le_list);

				gfs2_assert_warn(sdp, sdp->sd_log_num_buf);

				sdp->sd_log_num_buf--;

				gfs2_log_unlock(sdp);

				if (bh_ip->i_inode.i_private != NULL)

					tr->tr_num_databuf_rm++;

				else

				tr->tr_num_buf_rm++;

				brelse(bh);

			}

			if (bd) {

				gfs2_log_lock(sdp);

				if (bd->bd_ail) {

					u64 blkno = bh->b_blocknr;

					bd->bd_ail = NULL;

					list_del(&bd->bd_ail_st_list);

					list_del(&bd->bd_ail_gl_list);

					atomic_dec(&bd->bd_gl->gl_ail_count);

					brelse(bh);

					gfs2_log_unlock(sdp);

					gfs2_trans_add_revoke(sdp, blkno);

				} else

					gfs2_log_unlock(sdp);

					gfs2_remove_from_ail(NULL, bd);

					bh->b_private = NULL;

					bd->bd_bh = NULL;

					bd->bd_blkno = bh->b_blocknr;

					gfs2_trans_add_revoke(sdp, bd);

				}

			}



			lock_buffer(bh);

			clear_buffer_dirty(bh);

			clear_buffer_uptodate(bh);

			gfs2_log_unlock(sdp);

			unlock_buffer(bh);



			brelse(bh);

fs/gfs2/trans.c

+5 −5
Original line number Diff line number Diff line
@@ -142,12 +142,12 @@ void gfs2_trans_add_bh(struct gfs2_glock *gl, struct buffer_head *bh, int meta) 
	lops_add(sdp, &bd->bd_le);

}



void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, u64 blkno)

void gfs2_trans_add_revoke(struct gfs2_sbd *sdp, struct gfs2_bufdata *bd)

{

	struct gfs2_bufdata *bd = kmem_cache_alloc(gfs2_bufdata_cachep,

					  GFP_NOFS | __GFP_NOFAIL);

	BUG_ON(!list_empty(&bd->bd_le.le_list));

	BUG_ON(!list_empty(&bd->bd_ail_st_list));

	BUG_ON(!list_empty(&bd->bd_ail_gl_list));

	lops_init_le(&bd->bd_le, &gfs2_revoke_lops);

	bd->bd_blkno = blkno;

	lops_add(sdp, &bd->bd_le);

}
@@ -160,7 +160,7 @@ void gfs2_trans_add_unrevoke(struct gfs2_sbd *sdp, u64 blkno) 


	list_for_each_entry(bd, &sdp->sd_log_le_revoke, bd_le.le_list) {

		if (bd->bd_blkno == blkno) {

			list_del(&bd->bd_le.le_list);

			list_del_init(&bd->bd_le.le_list);

			gfs2_assert_withdraw(sdp, sdp->sd_log_num_revoke);

			sdp->sd_log_num_revoke--;

			found = 1;

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