diff options
| -rw-r--r-- | fs/xfs/xfs_log_cil.c | 227 |
1 files changed, 100 insertions, 127 deletions
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c index b20b15761e9c..c1a3384406fd 100644 --- a/fs/xfs/xfs_log_cil.c +++ b/fs/xfs/xfs_log_cil.c @@ -111,6 +111,53 @@ xlog_cil_lv_item_format( } /* + * Prepare the log item for insertion into the CIL. Calculate the difference in + * log space and vectors it will consume, and if it is a new item pin it as + * well. + */ +STATIC void +xfs_cil_prepare_item( + struct xlog *log, + struct xfs_log_vec *lv, + struct xfs_log_vec *old_lv, + int *diff_len, + int *diff_iovecs) +{ + /* Account for the new LV being passed in */ + if (lv->lv_buf_len != XFS_LOG_VEC_ORDERED) { + *diff_len += lv->lv_buf_len; + *diff_iovecs += lv->lv_niovecs; + } + + /* + * If there is no old LV, this is the first time we've seen the item in + * this CIL context and so we need to pin it. If we are replacing the + * old_lv, then remove the space it accounts for and free it. + */ + if (!old_lv) + lv->lv_item->li_ops->iop_pin(lv->lv_item); + else if (old_lv != lv) { + ASSERT(lv->lv_buf_len != XFS_LOG_VEC_ORDERED); + + *diff_len -= old_lv->lv_buf_len; + *diff_iovecs -= old_lv->lv_niovecs; + kmem_free(old_lv); + } + + /* attach new log vector to log item */ + lv->lv_item->li_lv = lv; + + /* + * If this is the first time the item is being committed to the + * CIL, store the sequence number on the log item so we can + * tell in future commits whether this is the first checkpoint + * the item is being committed into. + */ + if (!lv->lv_item->li_seq) + lv->lv_item->li_seq = log->l_cilp->xc_ctx->sequence; +} + +/* * Format log item into a flat buffers * * For delayed logging, we need to hold a formatted buffer containing all the @@ -136,24 +183,26 @@ xlog_cil_lv_item_format( * format the regions into the iclog as though they are being formatted * directly out of the objects themselves. */ -static struct xfs_log_vec * -xlog_cil_prepare_log_vecs( - struct xfs_trans *tp) +static void +xlog_cil_insert_format_items( + struct xlog *log, + struct xfs_trans *tp, + int *diff_len, + int *diff_iovecs) { struct xfs_log_item_desc *lidp; - struct xfs_log_vec *prev_lv = NULL; - struct xfs_log_vec *ret_lv = NULL; /* Bail out if we didn't find a log item. */ if (list_empty(&tp->t_items)) { ASSERT(0); - return NULL; + return; } list_for_each_entry(lidp, &tp->t_items, lid_trans) { struct xfs_log_item *lip = lidp->lid_item; struct xfs_log_vec *lv; + struct xfs_log_vec *old_lv; int niovecs = 0; int nbytes = 0; int buf_size; @@ -181,6 +230,9 @@ xlog_cil_prepare_log_vecs( nbytes = 0; } + /* grab the old item if it exists for reservation accounting */ + old_lv = lip->li_lv; + /* calc buffer size */ buf_size = sizeof(struct xfs_log_vec) + nbytes + niovecs * sizeof(struct xfs_log_iovec); @@ -194,9 +246,17 @@ xlog_cil_prepare_log_vecs( if (ordered) goto insert; + /* + * set the item up as though it is a new insertion so + * that the space reservation accounting is correct. + */ + *diff_iovecs -= lv->lv_niovecs; + *diff_len -= lv->lv_buf_len; + /* Ensure the lv is set up according to ->iop_size */ lv->lv_niovecs = niovecs; lv->lv_buf = (char *)lv + buf_size - nbytes; + lv->lv_buf_len = xlog_cil_lv_item_format(lip, lv); goto insert; } @@ -222,74 +282,8 @@ xlog_cil_prepare_log_vecs( lv->lv_buf_len = xlog_cil_lv_item_format(lip, lv); insert: ASSERT(lv->lv_buf_len <= nbytes); - if (!ret_lv) - ret_lv = lv; - else - prev_lv->lv_next = lv; - prev_lv = lv; - } - - return ret_lv; -} - -/* - * Prepare the log item for insertion into the CIL. Calculate the difference in - * log space and vectors it will consume, and if it is a new item pin it as - * well. - */ -STATIC void -xfs_cil_prepare_item( - struct xlog *log, - struct xfs_log_vec *lv, - int *len, - int *diff_iovecs) -{ - struct xfs_log_vec *old = lv->lv_item->li_lv; - - if (!old) { - /* new lv, must pin the log item */ - ASSERT(!lv->lv_item->li_lv); - - if (lv->lv_buf_len != XFS_LOG_VEC_ORDERED) { - *len += lv->lv_buf_len; - *diff_iovecs += lv->lv_niovecs; - } - lv->lv_item->li_ops->iop_pin(lv->lv_item); - - } else if (old != lv) { - /* existing lv on log item, space used is a delta */ - ASSERT((old->lv_buf && old->lv_buf_len && old->lv_niovecs) || - old->lv_buf_len == XFS_LOG_VEC_ORDERED); - - /* - * If the new item is ordered, keep the old one that is already - * tracking dirty or ordered regions - */ - if (lv->lv_buf_len == XFS_LOG_VEC_ORDERED) { - ASSERT(!lv->lv_buf); - kmem_free(lv); - return; - } - - *len += lv->lv_buf_len - old->lv_buf_len; - *diff_iovecs += lv->lv_niovecs - old->lv_niovecs; - kmem_free(old); - } else { - /* re-used lv */ - /* XXX: can't account for len/diff_iovecs yet */ + xfs_cil_prepare_item(log, lv, old_lv, diff_len, diff_iovecs); } - - /* attach new log vector to log item */ - lv->lv_item->li_lv = lv; - - /* - * If this is the first time the item is being committed to the - * CIL, store the sequence number on the log item so we can - * tell in future commits whether this is the first checkpoint - * the item is being committed into. - */ - if (!lv->lv_item->li_seq) - lv->lv_item->li_seq = log->l_cilp->xc_ctx->sequence; } /* @@ -302,53 +296,47 @@ xfs_cil_prepare_item( static void xlog_cil_insert_items( struct xlog *log, - struct xfs_log_vec *log_vector, - struct xlog_ticket *ticket) + struct xfs_trans *tp) { struct xfs_cil *cil = log->l_cilp; struct xfs_cil_ctx *ctx = cil->xc_ctx; - struct xfs_log_vec *lv; + struct xfs_log_item_desc *lidp; int len = 0; int diff_iovecs = 0; int iclog_space; - ASSERT(log_vector); + ASSERT(tp); /* - * Do all the accounting aggregation and switching of log vectors - * around in a separate loop to the insertion of items into the CIL. - * Then we can do a separate loop to update the CIL within a single - * lock/unlock pair. This reduces the number of round trips on the CIL - * lock from O(nr_logvectors) to O(1) and greatly reduces the overall - * hold time for the transaction commit. - * - * If this is the first time the item is being placed into the CIL in - * this context, pin it so it can't be written to disk until the CIL is - * flushed to the iclog and the iclog written to disk. - * * We can do this safely because the context can't checkpoint until we * are done so it doesn't matter exactly how we update the CIL. */ + xlog_cil_insert_format_items(log, tp, &len, &diff_iovecs); + + /* + * Now (re-)position everything modified at the tail of the CIL. + * We do this here so we only need to take the CIL lock once during + * the transaction commit. + */ spin_lock(&cil->xc_cil_lock); - for (lv = log_vector; lv; ) { - struct xfs_log_vec *next = lv->lv_next; + list_for_each_entry(lidp, &tp->t_items, lid_trans) { + struct xfs_log_item *lip = lidp->lid_item; - ASSERT(lv->lv_item->li_lv || list_empty(&lv->lv_item->li_cil)); - lv->lv_next = NULL; + /* Skip items which aren't dirty in this transaction. */ + if (!(lidp->lid_flags & XFS_LID_DIRTY)) + continue; - /* - * xfs_cil_prepare_item() may free the lv, so move the item on - * the CIL first. - */ - list_move_tail(&lv->lv_item->li_cil, &cil->xc_cil); - xfs_cil_prepare_item(log, lv, &len, &diff_iovecs); - lv = next; + list_move_tail(&lip->li_cil, &cil->xc_cil); } /* account for space used by new iovec headers */ len += diff_iovecs * sizeof(xlog_op_header_t); ctx->nvecs += diff_iovecs; + /* attach the transaction to the CIL if it has any busy extents */ + if (!list_empty(&tp->t_busy)) + list_splice_init(&tp->t_busy, &ctx->busy_extents); + /* * Now transfer enough transaction reservation to the context ticket * for the checkpoint. The context ticket is special - the unit @@ -357,10 +345,8 @@ xlog_cil_insert_items( * during the transaction commit. */ if (ctx->ticket->t_curr_res == 0) { - /* first commit in checkpoint, steal the header reservation */ - ASSERT(ticket->t_curr_res >= ctx->ticket->t_unit_res + len); ctx->ticket->t_curr_res = ctx->ticket->t_unit_res; - ticket->t_curr_res -= ctx->ticket->t_unit_res; + tp->t_ticket->t_curr_res -= ctx->ticket->t_unit_res; } /* do we need space for more log record headers? */ @@ -374,10 +360,10 @@ xlog_cil_insert_items( hdrs *= log->l_iclog_hsize + sizeof(struct xlog_op_header); ctx->ticket->t_unit_res += hdrs; ctx->ticket->t_curr_res += hdrs; - ticket->t_curr_res -= hdrs; - ASSERT(ticket->t_curr_res >= len); + tp->t_ticket->t_curr_res -= hdrs; + ASSERT(tp->t_ticket->t_curr_res >= len); } - ticket->t_curr_res -= len; + tp->t_ticket->t_curr_res -= len; ctx->space_used += len; spin_unlock(&cil->xc_cil_lock); @@ -746,38 +732,25 @@ xfs_log_commit_cil( int flags) { struct xlog *log = mp->m_log; + struct xfs_cil *cil = log->l_cilp; int log_flags = 0; - struct xfs_log_vec *log_vector; if (flags & XFS_TRANS_RELEASE_LOG_RES) log_flags = XFS_LOG_REL_PERM_RESERV; /* lock out background commit */ - down_read(&log->l_cilp->xc_ctx_lock); + down_read(&cil->xc_ctx_lock); - log_vector = xlog_cil_prepare_log_vecs(tp); - if (!log_vector) - return ENOMEM; - - if (commit_lsn) - *commit_lsn = log->l_cilp->xc_ctx->sequence; - - /* xlog_cil_insert_items() destroys log_vector list */ - xlog_cil_insert_items(log, log_vector, tp->t_ticket); + xlog_cil_insert_items(log, tp); /* check we didn't blow the reservation */ if (tp->t_ticket->t_curr_res < 0) - xlog_print_tic_res(log->l_mp, tp->t_ticket); + xlog_print_tic_res(mp, tp->t_ticket); - /* attach the transaction to the CIL if it has any busy extents */ - if (!list_empty(&tp->t_busy)) { - spin_lock(&log->l_cilp->xc_cil_lock); - list_splice_init(&tp->t_busy, - &log->l_cilp->xc_ctx->busy_extents); - spin_unlock(&log->l_cilp->xc_cil_lock); - } + tp->t_commit_lsn = cil->xc_ctx->sequence; + if (commit_lsn) + *commit_lsn = tp->t_commit_lsn; - tp->t_commit_lsn = *commit_lsn; xfs_log_done(mp, tp->t_ticket, NULL, log_flags); xfs_trans_unreserve_and_mod_sb(tp); @@ -792,11 +765,11 @@ xfs_log_commit_cil( * the log items. This affects (at least) processing of stale buffers, * inodes and EFIs. */ - xfs_trans_free_items(tp, *commit_lsn, 0); + xfs_trans_free_items(tp, tp->t_commit_lsn, 0); xlog_cil_push_background(log); - up_read(&log->l_cilp->xc_ctx_lock); + up_read(&cil->xc_ctx_lock); return 0; } |