From: Christoph Hellwig Date: Fri, 20 Mar 2020 15:49:20 +0000 (-0700) Subject: xfs: refactor xlog_state_clean_iclog X-Git-Tag: v5.10.7~2829^2~33 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c814b4f24ebacafb889e7975cb4a7136a5306921;p=platform%2Fkernel%2Flinux-rpi.git xfs: refactor xlog_state_clean_iclog Factor out a few self-contained helpers from xlog_state_clean_iclog, and update the documentation so it primarily documents why things happens instead of how. Signed-off-by: Christoph Hellwig Reviewed-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index 4f93035..6facbb9 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -2540,111 +2540,107 @@ next_lv: ***************************************************************************** */ +static void +xlog_state_activate_iclog( + struct xlog_in_core *iclog, + int *iclogs_changed) +{ + ASSERT(list_empty_careful(&iclog->ic_callbacks)); + + /* + * If the number of ops in this iclog indicate it just contains the + * dummy transaction, we can change state into IDLE (the second time + * around). Otherwise we should change the state into NEED a dummy. + * We don't need to cover the dummy. + */ + if (*iclogs_changed == 0 && + iclog->ic_header.h_num_logops == cpu_to_be32(XLOG_COVER_OPS)) { + *iclogs_changed = 1; + } else { + /* + * We have two dirty iclogs so start over. This could also be + * num of ops indicating this is not the dummy going out. + */ + *iclogs_changed = 2; + } + + iclog->ic_state = XLOG_STATE_ACTIVE; + iclog->ic_offset = 0; + iclog->ic_header.h_num_logops = 0; + memset(iclog->ic_header.h_cycle_data, 0, + sizeof(iclog->ic_header.h_cycle_data)); + iclog->ic_header.h_lsn = 0; +} + /* - * An iclog has just finished IO completion processing, so we need to update - * the iclog state and propagate that up into the overall log state. Hence we - * prepare the iclog for cleaning, and then clean all the pending dirty iclogs - * starting from the head, and then wake up any threads that are waiting for the - * iclog to be marked clean. - * - * The ordering of marking iclogs ACTIVE must be maintained, so an iclog - * doesn't become ACTIVE beyond one that is SYNCING. This is also required to - * maintain the notion that we use a ordered wait queue to hold off would be - * writers to the log when every iclog is trying to sync to disk. - * - * Caller must hold the icloglock before calling us. - * - * State Change: !IOERROR -> DIRTY -> ACTIVE + * Loop through all iclogs and mark all iclogs currently marked DIRTY as + * ACTIVE after iclog I/O has completed. */ -STATIC void -xlog_state_clean_iclog( +static void +xlog_state_activate_iclogs( struct xlog *log, - struct xlog_in_core *dirty_iclog) + int *iclogs_changed) { - struct xlog_in_core *iclog; - int changed = 0; - - /* Prepare the completed iclog. */ - if (dirty_iclog->ic_state != XLOG_STATE_IOERROR) - dirty_iclog->ic_state = XLOG_STATE_DIRTY; + struct xlog_in_core *iclog = log->l_iclog; - /* Walk all the iclogs to update the ordered active state. */ - iclog = log->l_iclog; do { - if (iclog->ic_state == XLOG_STATE_DIRTY) { - iclog->ic_state = XLOG_STATE_ACTIVE; - iclog->ic_offset = 0; - ASSERT(list_empty_careful(&iclog->ic_callbacks)); - /* - * If the number of ops in this iclog indicate it just - * contains the dummy transaction, we can - * change state into IDLE (the second time around). - * Otherwise we should change the state into - * NEED a dummy. - * We don't need to cover the dummy. - */ - if (!changed && - (be32_to_cpu(iclog->ic_header.h_num_logops) == - XLOG_COVER_OPS)) { - changed = 1; - } else { - /* - * We have two dirty iclogs so start over - * This could also be num of ops indicates - * this is not the dummy going out. - */ - changed = 2; - } - iclog->ic_header.h_num_logops = 0; - memset(iclog->ic_header.h_cycle_data, 0, - sizeof(iclog->ic_header.h_cycle_data)); - iclog->ic_header.h_lsn = 0; - } else if (iclog->ic_state == XLOG_STATE_ACTIVE) - /* do nothing */; - else - break; /* stop cleaning */ - iclog = iclog->ic_next; - } while (iclog != log->l_iclog); - + if (iclog->ic_state == XLOG_STATE_DIRTY) + xlog_state_activate_iclog(iclog, iclogs_changed); + /* + * The ordering of marking iclogs ACTIVE must be maintained, so + * an iclog doesn't become ACTIVE beyond one that is SYNCING. + */ + else if (iclog->ic_state != XLOG_STATE_ACTIVE) + break; + } while ((iclog = iclog->ic_next) != log->l_iclog); +} +static int +xlog_covered_state( + int prev_state, + int iclogs_changed) +{ /* - * Wake up threads waiting in xfs_log_force() for the dirty iclog - * to be cleaned. + * We usually go to NEED. But we go to NEED2 if the changed indicates we + * are done writing the dummy record. If we are done with the second + * dummy recored (DONE2), then we go to IDLE. */ - wake_up_all(&dirty_iclog->ic_force_wait); + switch (prev_state) { + case XLOG_STATE_COVER_IDLE: + case XLOG_STATE_COVER_NEED: + case XLOG_STATE_COVER_NEED2: + break; + case XLOG_STATE_COVER_DONE: + if (iclogs_changed == 1) + return XLOG_STATE_COVER_NEED2; + break; + case XLOG_STATE_COVER_DONE2: + if (iclogs_changed == 1) + return XLOG_STATE_COVER_IDLE; + break; + default: + ASSERT(0); + } - /* - * Change state for the dummy log recording. - * We usually go to NEED. But we go to NEED2 if the changed indicates - * we are done writing the dummy record. - * If we are done with the second dummy recored (DONE2), then - * we go to IDLE. - */ - if (changed) { - switch (log->l_covered_state) { - case XLOG_STATE_COVER_IDLE: - case XLOG_STATE_COVER_NEED: - case XLOG_STATE_COVER_NEED2: - log->l_covered_state = XLOG_STATE_COVER_NEED; - break; + return XLOG_STATE_COVER_NEED; +} - case XLOG_STATE_COVER_DONE: - if (changed == 1) - log->l_covered_state = XLOG_STATE_COVER_NEED2; - else - log->l_covered_state = XLOG_STATE_COVER_NEED; - break; +STATIC void +xlog_state_clean_iclog( + struct xlog *log, + struct xlog_in_core *dirty_iclog) +{ + int iclogs_changed = 0; - case XLOG_STATE_COVER_DONE2: - if (changed == 1) - log->l_covered_state = XLOG_STATE_COVER_IDLE; - else - log->l_covered_state = XLOG_STATE_COVER_NEED; - break; + if (dirty_iclog->ic_state != XLOG_STATE_IOERROR) + dirty_iclog->ic_state = XLOG_STATE_DIRTY; - default: - ASSERT(0); - } + xlog_state_activate_iclogs(log, &iclogs_changed); + wake_up_all(&dirty_iclog->ic_force_wait); + + if (iclogs_changed) { + log->l_covered_state = xlog_covered_state(log->l_covered_state, + iclogs_changed); } }