From 9b9107a5a8b190e6cf09bbdf893869c6a9c482cc Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 27 Aug 2007 13:54:05 +0100 Subject: [GFS2] Move pin/unpin into lops.c, clean up locking gfs2_pin and gfs2_unpin are only used in lops.c, despite being defined in meta_io.c, so this patch moves them into lops.c and makes them static. At the same time, its possible to clean up the locking in the buf and databuf _lo_add() functions so that we only need to grab the spinlock once. Also we have to move lock_buffer() around the _lo_add() functions since we can't do that in gfs2_pin() any more since we hold the spinlock for the duration of that function. As a result, the code shrinks by 12 lines and we do far fewer operations when adding buffers to the log. It also makes the code somewhat easier to read & understand. Signed-off-by: Steven Whitehouse --- fs/gfs2/lops.c | 117 +++++++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 89 insertions(+), 28 deletions(-) (limited to 'fs/gfs2/lops.c') diff --git a/fs/gfs2/lops.c b/fs/gfs2/lops.c index 7ef335623373..3ec587135d46 100644 --- a/fs/gfs2/lops.c +++ b/fs/gfs2/lops.c @@ -27,7 +27,71 @@ #include "trans.h" #include "util.h" -static void glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) +/** + * gfs2_pin - Pin a buffer in memory + * @sdp: The superblock + * @bh: The buffer to be pinned + * + * The log lock must be held when calling this function + */ +static void gfs2_pin(struct gfs2_sbd *sdp, struct buffer_head *bh) +{ + struct gfs2_bufdata *bd; + + gfs2_assert_withdraw(sdp, test_bit(SDF_JOURNAL_LIVE, &sdp->sd_flags)); + + clear_buffer_dirty(bh); + if (test_set_buffer_pinned(bh)) + gfs2_assert_withdraw(sdp, 0); + if (!buffer_uptodate(bh)) + gfs2_io_error_bh(sdp, bh); + bd = bh->b_private; + /* If this buffer is in the AIL and it has already been written + * to in-place disk block, remove it from the AIL. + */ + if (bd->bd_ail) + list_move(&bd->bd_ail_st_list, &bd->bd_ail->ai_ail2_list); + get_bh(bh); +} + +/** + * gfs2_unpin - Unpin a buffer + * @sdp: the filesystem the buffer belongs to + * @bh: The buffer to unpin + * @ai: + * + */ + +static void gfs2_unpin(struct gfs2_sbd *sdp, struct buffer_head *bh, + struct gfs2_ail *ai) +{ + struct gfs2_bufdata *bd = bh->b_private; + + gfs2_assert_withdraw(sdp, buffer_uptodate(bh)); + + if (!buffer_pinned(bh)) + gfs2_assert_withdraw(sdp, 0); + + lock_buffer(bh); + mark_buffer_dirty(bh); + clear_buffer_pinned(bh); + + gfs2_log_lock(sdp); + if (bd->bd_ail) { + list_del(&bd->bd_ail_st_list); + brelse(bh); + } else { + struct gfs2_glock *gl = bd->bd_gl; + list_add(&bd->bd_ail_gl_list, &gl->gl_ail_list); + atomic_inc(&gl->gl_ail_count); + } + bd->bd_ail = ai; + list_add(&bd->bd_ail_st_list, &ai->ai_ail1_list); + gfs2_log_unlock(sdp); + unlock_buffer(bh); +} + +static void __glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) { struct gfs2_glock *gl; struct gfs2_trans *tr = current->journal_info; @@ -38,15 +102,19 @@ static void glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) if (gfs2_assert_withdraw(sdp, gfs2_glock_is_held_excl(gl))) return; - gfs2_log_lock(sdp); - if (!list_empty(&le->le_list)){ - gfs2_log_unlock(sdp); + if (!list_empty(&le->le_list)) return; - } + gfs2_glock_hold(gl); set_bit(GLF_DIRTY, &gl->gl_flags); sdp->sd_log_num_gl++; list_add(&le->le_list, &sdp->sd_log_le_gl); +} + +static void glock_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) +{ + gfs2_log_lock(sdp); + __glock_lo_add(sdp, le); gfs2_log_unlock(sdp); } @@ -71,30 +139,25 @@ static void buf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) struct gfs2_bufdata *bd = container_of(le, struct gfs2_bufdata, bd_le); struct gfs2_trans *tr; + lock_buffer(bd->bd_bh); gfs2_log_lock(sdp); - if (!list_empty(&bd->bd_list_tr)) { - gfs2_log_unlock(sdp); - return; - } + if (!list_empty(&bd->bd_list_tr)) + goto out; tr = current->journal_info; tr->tr_touched = 1; tr->tr_num_buf++; list_add(&bd->bd_list_tr, &tr->tr_list_buf); - gfs2_log_unlock(sdp); - if (!list_empty(&le->le_list)) - return; - - gfs2_trans_add_gl(bd->bd_gl); - + goto out; + __glock_lo_add(sdp, &bd->bd_gl->gl_le); gfs2_meta_check(sdp, bd->bd_bh); gfs2_pin(sdp, bd->bd_bh); - gfs2_log_lock(sdp); sdp->sd_log_num_buf++; list_add(&le->le_list, &sdp->sd_log_le_buf); - gfs2_log_unlock(sdp); - tr->tr_num_buf_new++; +out: + gfs2_log_unlock(sdp); + unlock_buffer(bd->bd_bh); } static void buf_lo_incore_commit(struct gfs2_sbd *sdp, struct gfs2_trans *tr) @@ -476,31 +539,29 @@ static void databuf_lo_add(struct gfs2_sbd *sdp, struct gfs2_log_element *le) struct address_space *mapping = bd->bd_bh->b_page->mapping; struct gfs2_inode *ip = GFS2_I(mapping->host); + lock_buffer(bd->bd_bh); gfs2_log_lock(sdp); - if (!list_empty(&bd->bd_list_tr)) { - gfs2_log_unlock(sdp); - return; - } + if (!list_empty(&bd->bd_list_tr)) + goto out; tr->tr_touched = 1; if (gfs2_is_jdata(ip)) { tr->tr_num_buf++; list_add(&bd->bd_list_tr, &tr->tr_list_buf); } - gfs2_log_unlock(sdp); if (!list_empty(&le->le_list)) - return; + goto out; - gfs2_trans_add_gl(bd->bd_gl); + __glock_lo_add(sdp, &bd->bd_gl->gl_le); if (gfs2_is_jdata(ip)) { gfs2_pin(sdp, bd->bd_bh); tr->tr_num_databuf_new++; - } - gfs2_log_lock(sdp); - if (gfs2_is_jdata(ip)) sdp->sd_log_num_jdata++; + } sdp->sd_log_num_databuf++; list_add(&le->le_list, &sdp->sd_log_le_databuf); +out: gfs2_log_unlock(sdp); + unlock_buffer(bd->bd_bh); } static int gfs2_check_magic(struct buffer_head *bh) -- cgit v1.2.3-58-ga151