From mboxrd@z Thu Jan 1 00:00:00 1970 From: Bob Peterson Date: Mon, 13 Jan 2020 08:04:20 -0600 Subject: [Cluster-devel] [GFS2 PATCH 1/2 v3] Revert "gfs2: eliminate tr_num_revoke_rm" In-Reply-To: <20200113140421.867659-1-rpeterso@redhat.com> References: <20200113140421.867659-1-rpeterso@redhat.com> Message-ID: <20200113140421.867659-2-rpeterso@redhat.com> List-Id: To: cluster-devel.redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit This reverts commit e955537e3262de8e56f070b13817f525f472fa00. Before patch e955537e32, tr_num_revoke tracked the number of revokes added to the transaction, and tr_num_revoke_rm tracked how many revokes were removed. But since revokes are queued off the sdp (superblock) pointer, some transactions could remove more revokes than they added. (e.g. revokes added by a different process). Commit e955537e32 eliminated transaction variable tr_num_revoke_rm, but in order to do so, it changed the accounting to always use tr_num_revoke for its math. Since you can remove more revokes than you add, tr_num_revoke could now become a negative value. This negative value broke the assert in function gfs2_trans_end: if (gfs2_assert_withdraw(sdp, (nbuf <= tr->tr_blocks) && (tr->tr_num_revoke <= tr->tr_revokes))) One way to fix this is to simply remove the tr_num_revoke clause from the assert and allow the value to become negative. Andreas didn't like that idea, so instead, we decided to revert e955537e32. Signed-off-by: Bob Peterson --- fs/gfs2/incore.h | 1 + fs/gfs2/log.c | 3 ++- fs/gfs2/trans.c | 6 +++--- 3 files changed, 6 insertions(+), 4 deletions(-) diff --git a/fs/gfs2/incore.h b/fs/gfs2/incore.h index b5d9c11f4901..a5d81a261f77 100644 --- a/fs/gfs2/incore.h +++ b/fs/gfs2/incore.h @@ -505,6 +505,7 @@ struct gfs2_trans { unsigned int tr_num_buf_rm; unsigned int tr_num_databuf_rm; unsigned int tr_num_revoke; + unsigned int tr_num_revoke_rm; struct list_head tr_list; struct list_head tr_databuf; diff --git a/fs/gfs2/log.c b/fs/gfs2/log.c index 66189ae62c1d..6e2728416b6b 100644 --- a/fs/gfs2/log.c +++ b/fs/gfs2/log.c @@ -895,6 +895,7 @@ static void gfs2_merge_trans(struct gfs2_trans *old, struct gfs2_trans *new) old->tr_num_buf_rm += new->tr_num_buf_rm; old->tr_num_databuf_rm += new->tr_num_databuf_rm; old->tr_num_revoke += new->tr_num_revoke; + old->tr_num_revoke_rm += new->tr_num_revoke_rm; list_splice_tail_init(&new->tr_databuf, &old->tr_databuf); list_splice_tail_init(&new->tr_buf, &old->tr_buf); @@ -916,7 +917,7 @@ static void log_refund(struct gfs2_sbd *sdp, struct gfs2_trans *tr) set_bit(TR_ATTACHED, &tr->tr_flags); } - sdp->sd_log_commited_revoke += tr->tr_num_revoke; + sdp->sd_log_commited_revoke += tr->tr_num_revoke - tr->tr_num_revoke_rm; reserved = calc_reserved(sdp); maxres = sdp->sd_log_blks_reserved + tr->tr_reserved; gfs2_assert_withdraw(sdp, maxres >= reserved); diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index 4d01fe19c125..a685637a5b55 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -76,10 +76,10 @@ static void gfs2_print_trans(struct gfs2_sbd *sdp, const struct gfs2_trans *tr) fs_warn(sdp, "blocks=%u revokes=%u reserved=%u touched=%u\n", tr->tr_blocks, tr->tr_revokes, tr->tr_reserved, test_bit(TR_TOUCHED, &tr->tr_flags)); - fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u\n", + fs_warn(sdp, "Buf %u/%u Databuf %u/%u Revoke %u/%u\n", tr->tr_num_buf_new, tr->tr_num_buf_rm, tr->tr_num_databuf_new, tr->tr_num_databuf_rm, - tr->tr_num_revoke); + tr->tr_num_revoke, tr->tr_num_revoke_rm); } void gfs2_trans_end(struct gfs2_sbd *sdp) @@ -264,7 +264,7 @@ void gfs2_trans_remove_revoke(struct gfs2_sbd *sdp, u64 blkno, unsigned int len) if (bd->bd_gl) gfs2_glock_remove_revoke(bd->bd_gl); kmem_cache_free(gfs2_bufdata_cachep, bd); - tr->tr_num_revoke--; + tr->tr_num_revoke_rm++; if (--n == 0) break; } -- 2.24.1