diff options
Diffstat (limited to 'fs/xfs/xfs_log.c')
| -rw-r--r-- | fs/xfs/xfs_log.c | 739 |
1 files changed, 335 insertions, 404 deletions
diff --git a/fs/xfs/xfs_log.c b/fs/xfs/xfs_log.c index cee4ab9f8a9..0bf24b11d0c 100644 --- a/fs/xfs/xfs_log.c +++ b/fs/xfs/xfs_log.c @@ -47,7 +47,7 @@ STATIC xlog_t * xlog_alloc_log(xfs_mount_t *mp, xfs_buftarg_t *log_target, xfs_daddr_t blk_offset, int num_bblks); -STATIC int xlog_space_left(xlog_t *log, int cycle, int bytes); +STATIC int xlog_space_left(struct log *log, atomic64_t *head); STATIC int xlog_sync(xlog_t *log, xlog_in_core_t *iclog); STATIC void xlog_dealloc_log(xlog_t *log); @@ -70,7 +70,7 @@ STATIC void xlog_state_want_sync(xlog_t *log, xlog_in_core_t *iclog); /* local functions to manipulate grant head */ STATIC int xlog_grant_log_space(xlog_t *log, xlog_ticket_t *xtic); -STATIC void xlog_grant_push_ail(xfs_mount_t *mp, +STATIC void xlog_grant_push_ail(struct log *log, int need_bytes); STATIC void xlog_regrant_reserve_log_space(xlog_t *log, xlog_ticket_t *ticket); @@ -81,98 +81,73 @@ STATIC void xlog_ungrant_log_space(xlog_t *log, #if defined(DEBUG) STATIC void xlog_verify_dest_ptr(xlog_t *log, char *ptr); -STATIC void xlog_verify_grant_head(xlog_t *log, int equals); +STATIC void xlog_verify_grant_tail(struct log *log); STATIC void xlog_verify_iclog(xlog_t *log, xlog_in_core_t *iclog, int count, boolean_t syncing); STATIC void xlog_verify_tail_lsn(xlog_t *log, xlog_in_core_t *iclog, xfs_lsn_t tail_lsn); #else #define xlog_verify_dest_ptr(a,b) -#define xlog_verify_grant_head(a,b) +#define xlog_verify_grant_tail(a) #define xlog_verify_iclog(a,b,c,d) #define xlog_verify_tail_lsn(a,b,c) #endif STATIC int xlog_iclogs_empty(xlog_t *log); - static void -xlog_ins_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic) +xlog_grant_sub_space( + struct log *log, + atomic64_t *head, + int bytes) { - if (*qp) { - tic->t_next = (*qp); - tic->t_prev = (*qp)->t_prev; - (*qp)->t_prev->t_next = tic; - (*qp)->t_prev = tic; - } else { - tic->t_prev = tic->t_next = tic; - *qp = tic; - } + int64_t head_val = atomic64_read(head); + int64_t new, old; - tic->t_flags |= XLOG_TIC_IN_Q; -} + do { + int cycle, space; -static void -xlog_del_ticketq(struct xlog_ticket **qp, struct xlog_ticket *tic) -{ - if (tic == tic->t_next) { - *qp = NULL; - } else { - *qp = tic->t_next; - tic->t_next->t_prev = tic->t_prev; - tic->t_prev->t_next = tic->t_next; - } + xlog_crack_grant_head_val(head_val, &cycle, &space); - tic->t_next = tic->t_prev = NULL; - tic->t_flags &= ~XLOG_TIC_IN_Q; + space -= bytes; + if (space < 0) { + space += log->l_logsize; + cycle--; + } + + old = head_val; + new = xlog_assign_grant_head_val(cycle, space); + head_val = atomic64_cmpxchg(head, old, new); + } while (head_val != old); } static void -xlog_grant_sub_space(struct log *log, int bytes) +xlog_grant_add_space( + struct log *log, + atomic64_t *head, + int bytes) { - log->l_grant_write_bytes -= bytes; - if (log->l_grant_write_bytes < 0) { - log->l_grant_write_bytes += log->l_logsize; - log->l_grant_write_cycle--; - } - - log->l_grant_reserve_bytes -= bytes; - if ((log)->l_grant_reserve_bytes < 0) { - log->l_grant_reserve_bytes += log->l_logsize; - log->l_grant_reserve_cycle--; - } + int64_t head_val = atomic64_read(head); + int64_t new, old; -} + do { + int tmp; + int cycle, space; -static void -xlog_grant_add_space_write(struct log *log, int bytes) -{ - int tmp = log->l_logsize - log->l_grant_write_bytes; - if (tmp > bytes) - log->l_grant_write_bytes += bytes; - else { - log->l_grant_write_cycle++; - log->l_grant_write_bytes = bytes - tmp; - } -} + xlog_crack_grant_head_val(head_val, &cycle, &space); -static void -xlog_grant_add_space_reserve(struct log *log, int bytes) -{ - int tmp = log->l_logsize - log->l_grant_reserve_bytes; - if (tmp > bytes) - log->l_grant_reserve_bytes += bytes; - else { - log->l_grant_reserve_cycle++; - log->l_grant_reserve_bytes = bytes - tmp; - } -} + tmp = log->l_logsize - space; + if (tmp > bytes) + space += bytes; + else { + space = bytes - tmp; + cycle++; + } -static inline void -xlog_grant_add_space(struct log *log, int bytes) -{ - xlog_grant_add_space_write(log, bytes); - xlog_grant_add_space_reserve(log, bytes); + old = head_val; + new = xlog_assign_grant_head_val(cycle, space); + head_val = atomic64_cmpxchg(head, old, new); + } while (head_val != old); } static void @@ -355,7 +330,7 @@ xfs_log_reserve( trace_xfs_log_reserve(log, internal_ticket); - xlog_grant_push_ail(mp, internal_ticket->t_unit_res); + xlog_grant_push_ail(log, internal_ticket->t_unit_res); retval = xlog_regrant_write_log_space(log, internal_ticket); } else { /* may sleep if need to allocate more tickets */ @@ -369,7 +344,7 @@ xfs_log_reserve( trace_xfs_log_reserve(log, internal_ticket); - xlog_grant_push_ail(mp, + xlog_grant_push_ail(log, (internal_ticket->t_unit_res * internal_ticket->t_cnt)); retval = xlog_grant_log_space(log, internal_ticket); @@ -584,8 +559,8 @@ xfs_log_unmount_write(xfs_mount_t *mp) if (!(iclog->ic_state == XLOG_STATE_ACTIVE || iclog->ic_state == XLOG_STATE_DIRTY)) { if (!XLOG_FORCED_SHUTDOWN(log)) { - sv_wait(&iclog->ic_force_wait, PMEM, - &log->l_icloglock, s); + xlog_wait(&iclog->ic_force_wait, + &log->l_icloglock); } else { spin_unlock(&log->l_icloglock); } @@ -625,8 +600,8 @@ xfs_log_unmount_write(xfs_mount_t *mp) || iclog->ic_state == XLOG_STATE_DIRTY || iclog->ic_state == XLOG_STATE_IOERROR) ) { - sv_wait(&iclog->ic_force_wait, PMEM, - &log->l_icloglock, s); + xlog_wait(&iclog->ic_force_wait, + &log->l_icloglock); } else { spin_unlock(&log->l_icloglock); } @@ -703,55 +678,46 @@ xfs_log_move_tail(xfs_mount_t *mp, { xlog_ticket_t *tic; xlog_t *log = mp->m_log; - int need_bytes, free_bytes, cycle, bytes; + int need_bytes, free_bytes; if (XLOG_FORCED_SHUTDOWN(log)) return; - if (tail_lsn == 0) { - /* needed since sync_lsn is 64 bits */ - spin_lock(&log->l_icloglock); - tail_lsn = log->l_last_sync_lsn; - spin_unlock(&log->l_icloglock); - } - - spin_lock(&log->l_grant_lock); + if (tail_lsn == 0) + tail_lsn = atomic64_read(&log->l_last_sync_lsn); - /* Also an invalid lsn. 1 implies that we aren't passing in a valid - * tail_lsn. - */ - if (tail_lsn != 1) { - log->l_tail_lsn = tail_lsn; - } + /* tail_lsn == 1 implies that we weren't passed a valid value. */ + if (tail_lsn != 1) + atomic64_set(&log->l_tail_lsn, tail_lsn); - if ((tic = log->l_write_headq)) { + if (!list_empty_careful(&log->l_writeq)) { #ifdef DEBUG if (log->l_flags & XLOG_ACTIVE_RECOVERY) panic("Recovery problem"); #endif - cycle = log->l_grant_write_cycle; - bytes = log->l_grant_write_bytes; - free_bytes = xlog_space_left(log, cycle, bytes); - do { + spin_lock(&log->l_grant_write_lock); + free_bytes = xlog_space_left(log, &log->l_grant_write_head); + list_for_each_entry(tic, &log->l_writeq, t_queue) { ASSERT(tic->t_flags & XLOG_TIC_PERM_RESERV); if (free_bytes < tic->t_unit_res && tail_lsn != 1) break; tail_lsn = 0; free_bytes -= tic->t_unit_res; - sv_signal(&tic->t_wait); - tic = tic->t_next; - } while (tic != log->l_write_headq); + trace_xfs_log_regrant_write_wake_up(log, tic); + wake_up(&tic->t_wait); + } + spin_unlock(&log->l_grant_write_lock); } - if ((tic = log->l_reserve_headq)) { + + if (!list_empty_careful(&log->l_reserveq)) { #ifdef DEBUG if (log->l_flags & XLOG_ACTIVE_RECOVERY) panic("Recovery problem"); #endif - cycle = log->l_grant_reserve_cycle; - bytes = log->l_grant_reserve_bytes; - free_bytes = xlog_space_left(log, cycle, bytes); - do { + spin_lock(&log->l_grant_reserve_lock); + free_bytes = xlog_space_left(log, &log->l_grant_reserve_head); + list_for_each_entry(tic, &log->l_reserveq, t_queue) { if (tic->t_flags & XLOG_TIC_PERM_RESERV) need_bytes = tic->t_unit_res*tic->t_cnt; else @@ -760,12 +726,12 @@ xfs_log_move_tail(xfs_mount_t *mp, break; tail_lsn = 0; free_bytes -= need_bytes; - sv_signal(&tic->t_wait); - tic = tic->t_next; - } while (tic != log->l_reserve_headq); + trace_xfs_log_grant_wake_up(log, tic); + wake_up(&tic->t_wait); + } + spin_unlock(&log->l_grant_reserve_lock); } - spin_unlock(&log->l_grant_lock); -} /* xfs_log_move_tail */ +} /* * Determine if we have a transaction that has gone to disk @@ -831,23 +797,19 @@ xfs_log_need_covered(xfs_mount_t *mp) * We may be holding the log iclog lock upon entering this routine. */ xfs_lsn_t -xlog_assign_tail_lsn(xfs_mount_t *mp) +xlog_assign_tail_lsn( + struct xfs_mount *mp) { - xfs_lsn_t tail_lsn; - xlog_t *log = mp->m_log; + xfs_lsn_t tail_lsn; + struct log *log = mp->m_log; tail_lsn = xfs_trans_ail_tail(mp->m_ail); - spin_lock(&log->l_grant_lock); - if (tail_lsn != 0) { - log->l_tail_lsn = tail_lsn; - } else { - tail_lsn = log->l_tail_lsn = log->l_last_sync_lsn; - } - spin_unlock(&log->l_grant_lock); + if (!tail_lsn) + tail_lsn = atomic64_read(&log->l_last_sync_lsn); + atomic64_set(&log->l_tail_lsn, tail_lsn); return tail_lsn; -} /* xlog_assign_tail_lsn */ - +} /* * Return the space in the log between the tail and the head. The head @@ -864,21 +826,26 @@ xlog_assign_tail_lsn(xfs_mount_t *mp) * result is that we return the size of the log as the amount of space left. */ STATIC int -xlog_space_left(xlog_t *log, int cycle, int bytes) -{ - int free_bytes; - int tail_bytes; - int tail_cycle; - - tail_bytes = BBTOB(BLOCK_LSN(log->l_tail_lsn)); - tail_cycle = CYCLE_LSN(log->l_tail_lsn); - if ((tail_cycle == cycle) && (bytes >= tail_bytes)) { - free_bytes = log->l_logsize - (bytes - tail_bytes); - } else if ((tail_cycle + 1) < cycle) { +xlog_space_left( + struct log *log, + atomic64_t *head) +{ + int free_bytes; + int tail_bytes; + int tail_cycle; + int head_cycle; + int head_bytes; + + xlog_crack_grant_head(head, &head_cycle, &head_bytes); + xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_bytes); + tail_bytes = BBTOB(tail_bytes); + if (tail_cycle == head_cycle && head_bytes >= tail_bytes) + free_bytes = log->l_logsize - (head_bytes - tail_bytes); + else if (tail_cycle + 1 < head_cycle) return 0; - } else if (tail_cycle < cycle) { - ASSERT(tail_cycle == (cycle - 1)); - free_bytes = tail_bytes - bytes; + else if (tail_cycle < head_cycle) { + ASSERT(tail_cycle == (head_cycle - 1)); + free_bytes = tail_bytes - head_bytes; } else { /* * The reservation head is behind the tail. @@ -889,12 +856,12 @@ xlog_space_left(xlog_t *log, int cycle, int bytes) "xlog_space_left: head behind tail\n" " tail_cycle = %d, tail_bytes = %d\n" " GH cycle = %d, GH bytes = %d", - tail_cycle, tail_bytes, cycle, bytes); + tail_cycle, tail_bytes, head_cycle, head_bytes); ASSERT(0); free_bytes = log->l_logsize; } return free_bytes; -} /* xlog_space_left */ +} /* @@ -1047,12 +1014,16 @@ xlog_alloc_log(xfs_mount_t *mp, log->l_flags |= XLOG_ACTIVE_RECOVERY; log->l_prev_block = -1; - log->l_tail_lsn = xlog_assign_lsn(1, 0); /* log->l_tail_lsn = 0x100000000LL; cycle = 1; current block = 0 */ - log->l_last_sync_lsn = log->l_tail_lsn; + xlog_assign_atomic_lsn(&log->l_tail_lsn, 1, 0); + xlog_assign_atomic_lsn(&log->l_last_sync_lsn, 1, 0); log->l_curr_cycle = 1; /* 0 is bad since this is initial value */ - log->l_grant_reserve_cycle = 1; - log->l_grant_write_cycle = 1; + xlog_assign_grant_head(&log->l_grant_reserve_head, 1, 0); + xlog_assign_grant_head(&log->l_grant_write_head, 1, 0); + INIT_LIST_HEAD(&log->l_reserveq); + INIT_LIST_HEAD(&log->l_writeq); + spin_lock_init(&log->l_grant_reserve_lock); + spin_lock_init(&log->l_grant_write_lock); error = EFSCORRUPTED; if (xfs_sb_version_hassector(&mp->m_sb)) { @@ -1094,8 +1065,7 @@ xlog_alloc_log(xfs_mount_t *mp, log->l_xbuf = bp; spin_lock_init(&log->l_icloglock); - spin_lock_init(&log->l_grant_lock); - sv_init(&log->l_flush_wait, 0, "flush_wait"); + init_waitqueue_head(&log->l_flush_wait); /* log record size must be multiple of BBSIZE; see xlog_rec_header_t */ ASSERT((XFS_BUF_SIZE(bp) & BBMASK) == 0); @@ -1151,8 +1121,8 @@ xlog_alloc_log(xfs_mount_t *mp, ASSERT(XFS_BUF_ISBUSY(iclog->ic_bp)); ASSERT(XFS_BUF_VALUSEMA(iclog->ic_bp) <= 0); - sv_init(&iclog->ic_force_wait, SV_DEFAULT, "iclog-force"); - sv_init(&iclog->ic_write_wait, SV_DEFAULT, "iclog-write"); + init_waitqueue_head(&iclog->ic_force_wait); + init_waitqueue_head(&iclog->ic_write_wait); iclogp = &iclog->ic_next; } @@ -1167,15 +1137,11 @@ xlog_alloc_log(xfs_mount_t *mp, out_free_iclog: for (iclog = log->l_iclog; iclog; iclog = prev_iclog) { prev_iclog = iclog->ic_next; - if (iclog->ic_bp) { - sv_destroy(&iclog->ic_force_wait); - sv_destroy(&iclog->ic_write_wait); + if (iclog->ic_bp) xfs_buf_free(iclog->ic_bp); - } kmem_free(iclog); } spinlock_destroy(&log->l_icloglock); - spinlock_destroy(&log->l_grant_lock); xfs_buf_free(log->l_xbuf); out_free_log: kmem_free(log); @@ -1223,61 +1189,60 @@ xlog_commit_record( * water mark. In this manner, we would be creating a low water mark. */ STATIC void -xlog_grant_push_ail(xfs_mount_t *mp, - int need_bytes) +xlog_grant_push_ail( + struct log *log, + int need_bytes) { - xlog_t *log = mp->m_log; /* pointer to the log */ - xfs_lsn_t tail_lsn; /* lsn of the log tail */ - xfs_lsn_t threshold_lsn = 0; /* lsn we'd like to be at */ - int free_blocks; /* free blocks left to write to */ - int free_bytes; /* free bytes left to write to */ - int threshold_block; /* block in lsn we'd like to be at */ - int threshold_cycle; /* lsn cycle we'd like to be at */ - int free_threshold; - - ASSERT(BTOBB(need_bytes) < log->l_logBBsize); - - spin_lock(&log->l_grant_lock); - free_bytes = xlog_space_left(log, - log->l_grant_reserve_cycle, - log->l_grant_reserve_bytes); - tail_lsn = log->l_tail_lsn; - free_blocks = BTOBBT(free_bytes); - - /* - * Set the threshold for the minimum number of free blocks in the - * log to the maximum of what the caller needs, one quarter of the - * log, and 256 blocks. - */ - free_threshold = BTOBB(need_bytes); - free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2)); - free_threshold = MAX(free_threshold, 256); - if (free_blocks < free_threshold) { - threshold_block = BLOCK_LSN(tail_lsn) + free_threshold; - threshold_cycle = CYCLE_LSN(tail_lsn); + xfs_lsn_t threshold_lsn = 0; + xfs_lsn_t last_sync_lsn; + int free_blocks; + int free_bytes; + int threshold_block; + int threshold_cycle; + int free_threshold; + + ASSERT(BTOBB(need_bytes) < log->l_logBBsize); + + free_bytes = xlog_space_left(log, &log->l_grant_reserve_head); + free_blocks = BTOBBT(free_bytes); + + /* + * Set the threshold for the minimum number of free blocks in the + * log to the maximum of what the caller needs, one quarter of the + * log, and 256 blocks. + */ + free_threshold = BTOBB(need_bytes); + free_threshold = MAX(free_threshold, (log->l_logBBsize >> 2)); + free_threshold = MAX(free_threshold, 256); + if (free_blocks >= free_threshold) + return; + + xlog_crack_atomic_lsn(&log->l_tail_lsn, &threshold_cycle, + &threshold_block); + threshold_block += free_threshold; if (threshold_block >= log->l_logBBsize) { - threshold_block -= log->l_logBBsize; - threshold_cycle += 1; + threshold_block -= log->l_logBBsize; + threshold_cycle += 1; } - threshold_lsn = xlog_assign_lsn(threshold_cycle, threshold_block); + threshold_lsn = xlog_assign_lsn(threshold_cycle, + threshold_block); + /* + * Don't pass in an lsn greater than the lsn of the last + * log record known to be on disk. Use a snapshot of the last sync lsn + * so that it doesn't change between the compare and the set. + */ + last_sync_lsn = atomic64_read(&log->l_last_sync_lsn); + if (XFS_LSN_CMP(threshold_lsn, last_sync_lsn) > 0) + threshold_lsn = last_sync_lsn; - /* Don't pass in an lsn greater than the lsn of the last - * log record known to be on disk. + /* + * Get the transaction layer to kick the dirty buffers out to + * disk asynchronously. No point in trying to do this if + * the filesystem is shutting down. */ - if (XFS_LSN_CMP(threshold_lsn, log->l_last_sync_lsn) > 0) - threshold_lsn = log->l_last_sync_lsn; - } - spin_unlock(&log->l_grant_lock); - - /* - * Get the transaction layer to kick the dirty buffers out to - * disk asynchronously. No point in trying to do this if - * the filesystem is shutting down. - */ - if (threshold_lsn && - !XLOG_FORCED_SHUTDOWN(log)) - xfs_trans_ail_push(log->l_ailp, threshold_lsn); -} /* xlog_grant_push_ail */ + if (!XLOG_FORCED_SHUTDOWN(log)) + xfs_trans_ail_push(log->l_ailp, threshold_lsn); +} /* * The bdstrat callback function for log bufs. This gives us a central @@ -1372,9 +1337,8 @@ xlog_sync(xlog_t *log, roundoff < BBTOB(1))); /* move grant heads by roundoff in sync */ - spin_lock(&log->l_grant_lock); - xlog_grant_add_space(log, roundoff); - spin_unlock(&log->l_grant_lock); + xlog_grant_add_space(log, &log->l_grant_reserve_head, roundoff); + xlog_grant_add_space(log, &log->l_grant_write_head, roundoff); /* put cycle number in every block */ xlog_pack_data(log, iclog, roundoff); @@ -1489,15 +1453,12 @@ xlog_dealloc_log(xlog_t *log) iclog = log->l_iclog; for (i=0; i<log->l_iclog_bufs; i++) { - sv_destroy(&iclog->ic_force_wait); - sv_destroy(&iclog->ic_write_wait); xfs_buf_free(iclog->ic_bp); next_iclog = iclog->ic_next; kmem_free(iclog); iclog = next_iclog; } spinlock_destroy(&log->l_icloglock); - spinlock_destroy(&log->l_grant_lock); xfs_buf_free(log->l_xbuf); log->l_mp->m_log = NULL; @@ -2232,7 +2193,7 @@ xlog_state_do_callback( lowest_lsn = xlog_get_lowest_lsn(log); if (lowest_lsn && XFS_LSN_CMP(lowest_lsn, - be64_to_cpu(iclog->ic_header.h_lsn)) < 0) { + be64_to_cpu(iclog->ic_header.h_lsn)) < 0) { iclog = iclog->ic_next; continue; /* Leave this iclog for * another thread */ @@ -2240,23 +2201,21 @@ xlog_state_do_callback( iclog->ic_state = XLOG_STATE_CALLBACK; - spin_unlock(&log->l_icloglock); - /* l_last_sync_lsn field protected by - * l_grant_lock. Don't worry about iclog's lsn. - * No one else can be here except us. + /* + * update the last_sync_lsn before we drop the + * icloglock to ensure we are the only one that + * can update it. */ - spin_lock(&log->l_grant_lock); - ASSERT(XFS_LSN_CMP(log->l_last_sync_lsn, - be64_to_cpu(iclog->ic_header.h_lsn)) <= 0); - log->l_last_sync_lsn = - be64_to_cpu(iclog->ic_header.h_lsn); - spin_unlock(&log->l_grant_lock); + ASSERT(XFS_LSN_CMP(atomic64_read(&log->l_last_sync_lsn), + be64_to_cpu(iclog->ic_header.h_lsn)) <= 0); + atomic64_set(&log->l_last_sync_lsn, + be64_to_cpu(iclog->ic_header.h_lsn)); - } else { - spin_unlock(&log->l_icloglock); + } else ioerrors++; - } + + spin_unlock(&log->l_icloglock); /* * Keep processing entries in the callback list until @@ -2297,7 +2256,7 @@ xlog_state_do_callback( xlog_state_clean_log(log); /* wake up threads waiting in xfs_log_force() */ - sv_broadcast(&iclog->ic_force_wait); + wake_up_all(&iclog->ic_force_wait); iclog = iclog->ic_next; } while (first_iclog != iclog); @@ -2344,7 +2303,7 @@ xlog_state_do_callback( spin_unlock(&log->l_icloglock); if (wake) - sv_broadcast(&log->l_flush_wait); + wake_up_all(&log->l_flush_wait); } @@ -2395,7 +2354,7 @@ xlog_state_done_syncing( * iclog buffer, we wake them all, one will get to do the * I/O, the others get to wait for the result. */ - sv_broadcast(&iclog->ic_write_wait); + wake_up_all(&iclog->ic_write_wait); spin_unlock(&log->l_icloglock); xlog_state_do_callback(log, aborted, iclog); /* also cleans log */ } /* xlog_state_done_syncing */ @@ -2444,7 +2403,7 @@ restart: XFS_STATS_INC(xs_log_noiclogs); /* Wait for log writes to have flushed */ - sv_wait(&log->l_flush_wait, 0, &log->l_icloglock, 0); + xlog_wait(&log->l_flush_wait, &log->l_icloglock); goto restart; } @@ -2527,6 +2486,18 @@ restart: * * Once a ticket gets put onto the reserveq, it will only return after * the needed reservation is satisfied. + * + * This function is structured so that it has a lock free fast path. This is + * necessary because every new transaction reservation will come through this + * path. Hence any lock will be globally hot if we take it unconditionally on + * every pass. + * + * As tickets are only ever moved on and off the reserveq under the + * l_grant_reserve_lock, we only need to take that lock if we are going + * to add the ticket to the queue and sleep. We can avoid taking the lock if the + * ticket was never added to the reserveq because the t_queue list head will be + * empty and we hold the only reference to it so it can safely be checked + * unlocked. */ STATIC int xlog_grant_log_space(xlog_t *log, @@ -2534,24 +2505,27 @@ xlog_grant_log_space(xlog_t *log, { int free_bytes; int need_bytes; -#ifdef DEBUG - xfs_lsn_t tail_lsn; -#endif - #ifdef DEBUG if (log->l_flags & XLOG_ACTIVE_RECOVERY) panic("grant Recovery problem"); #endif - /* Is there space or do we need to sleep? */ - spin_lock(&log->l_grant_lock); - trace_xfs_log_grant_enter(log, tic); + need_bytes = tic->t_unit_res; + if (tic->t_flags & XFS_LOG_PERM_RESERV) + need_bytes *= tic->t_ocnt; + /* something is already sleeping; insert new transaction at end */ - if (log->l_reserve_headq) { - xlog_ins_ticketq(&log->l_reserve_headq, tic); + if (!list_empty_careful(&log->l_reserveq)) { + spin_lock(&log->l_grant_reserve_lock); + /* recheck the queue now we are locked */ + if (list_empty(&log->l_reserveq)) { + spin_unlock(&log->l_grant_reserve_lock); + goto redo; + } + list_add_tail(&tic->t_queue, &log->l_reserveq); trace_xfs_log_grant_sleep1(log, tic); @@ -2563,72 +2537,57 @@ xlog_grant_log_space(xlog_t *log, goto error_return; XFS_STATS_INC(xs_sleep_logspace); - sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); + xlog_wait(&tic->t_wait, &log->l_grant_reserve_lock); + /* * If we got an error, and the filesystem is shutting down, * we'll catch it down below. So just continue... */ trace_xfs_log_grant_wake1(log, tic); - spin_lock(&log->l_grant_lock); } - if (tic->t_flags & XFS_LOG_PERM_RESERV) - need_bytes = tic->t_unit_res*tic->t_ocnt; - else - need_bytes = tic->t_unit_res; redo: if (XLOG_FORCED_SHUTDOWN(log)) - goto error_return; + goto error_return_unlocked; - free_bytes = xlog_space_left(log, log->l_grant_reserve_cycle, - log->l_grant_reserve_bytes); + free_bytes = xlog_space_left(log, &log->l_grant_reserve_head); if (free_bytes < need_bytes) { - if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) - xlog_ins_ticketq(&log->l_reserve_headq, tic); + spin_lock(&log->l_grant_reserve_lock); + if (list_empty(&tic->t_queue)) + list_add_tail(&tic->t_queue, &log->l_reserveq); trace_xfs_log_grant_sleep2(log, tic); - spin_unlock(&log->l_grant_lock); - xlog_grant_push_ail(log->l_mp, need_bytes); - spin_lock(&log->l_grant_lock); - - XFS_STATS_INC(xs_sleep_logspace); - sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); - - spin_lock(&log->l_grant_lock); if (XLOG_FORCED_SHUTDOWN(log)) goto error_return; - trace_xfs_log_grant_wake2(log, tic); + xlog_grant_push_ail(log, need_bytes); + + XFS_STATS_INC(xs_sleep_logspace); + xlog_wait(&tic->t_wait, &log->l_grant_reserve_lock); + trace_xfs_log_grant_wake2(log, tic); goto redo; - } else if (tic->t_flags & XLOG_TIC_IN_Q) - xlog_del_ticketq(&log->l_reserve_headq, tic); + } - /* we've got enough space */ - xlog_grant_add_space(log, need_bytes); -#ifdef DEBUG - tail_lsn = log->l_tail_lsn; - /* - * Check to make sure the grant write head didn't just over lap the - * tail. If the cycles are the same, we can't be overlapping. - * Otherwise, make sure that the cycles differ by exactly one and - * check the byte count. - */ - if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { - ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); - ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); + if (!list_empty(&tic->t_queue)) { + spin_lock(&log->l_grant_reserve_lock); + list_del_init(&tic->t_queue); + spin_unlock(&log->l_grant_reserve_lock); } -#endif + + /* we've got enough space */ + xlog_grant_add_space(log, &log->l_grant_reserve_head, need_bytes); + xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes); trace_xfs_log_grant_exit(log, tic); - xlog_verify_grant_head(log, 1); - spin_unlock(&log->l_grant_lock); + xlog_verify_grant_tail(log); return 0; - error_return: - if (tic->t_flags & XLOG_TIC_IN_Q) - xlog_del_ticketq(&log->l_reserve_headq, tic); - +error_return_unlocked: + spin_lock(&log->l_grant_reserve_lock); +error_return: + list_del_init(&tic->t_queue); + spin_unlock(&log->l_grant_reserve_lock); trace_xfs_log_grant_error(log, tic); /* @@ -2638,7 +2597,6 @@ redo: */ tic->t_curr_res = 0; tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ - spin_unlock(&log->l_grant_lock); return XFS_ERROR(EIO); } /* xlog_grant_log_space */ @@ -2646,17 +2604,14 @@ redo: /* * Replenish the byte reservation required by moving the grant write head. * - * + * Similar to xlog_grant_log_space, the function is structured to have a lock + * free fast path. */ STATIC int xlog_regrant_write_log_space(xlog_t *log, xlog_ticket_t *tic) { int free_bytes, need_bytes; - xlog_ticket_t *ntic; -#ifdef DEBUG - xfs_lsn_t tail_lsn; -#endif tic->t_curr_res = tic->t_unit_res; xlog_tic_reset_res(tic); @@ -2669,12 +2624,9 @@ xlog_regrant_write_log_space(xlog_t *log, panic("regrant Recovery problem"); #endif - spin_lock(&log->l_grant_lock); - trace_xfs_log_regrant_write_enter(log, tic); - if (XLOG_FORCED_SHUTDOWN(log)) - goto error_return; + goto error_return_unlocked; /* If there are other waiters on the queue then give them a * chance at logspace before us. Wake up the first waiters, @@ -2683,92 +2635,76 @@ xlog_regrant_write_log_space(xlog_t *log, * this transaction. */ need_bytes = tic->t_unit_res; - if ((ntic = log->l_write_headq)) { - free_bytes = xlog_space_left(log, log->l_grant_write_cycle, - log->l_grant_write_bytes); - do { + if (!list_empty_careful(&log->l_writeq)) { + struct xlog_ticket *ntic; + + spin_lock(&log->l_grant_write_lock); + free_bytes = xlog_space_left(log, &log->l_grant_write_head); + list_for_each_entry(ntic, &log->l_writeq, t_queue) { ASSERT(ntic->t_flags & XLOG_TIC_PERM_RESERV); if (free_bytes < ntic->t_unit_res) break; free_bytes -= ntic->t_unit_res; - sv_signal(&ntic->t_wait); - ntic = ntic->t_next; - } while (ntic != log->l_write_headq); - - if (ntic != log->l_write_headq) { - if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) - xlog_ins_ticketq(&log->l_write_headq, tic); + wake_up(&ntic->t_wait); + } + if (ntic != list_first_entry(&log->l_writeq, + struct xlog_ticket, t_queue)) { + if (list_empty(&tic->t_queue)) + list_add_tail(&tic->t_queue, &log->l_writeq); trace_xfs_log_regrant_write_sleep1(log, tic); - spin_unlock(&log->l_grant_lock); - xlog_grant_push_ail(log->l_mp, need_bytes); - spin_lock(&log->l_grant_lock); + xlog_grant_push_ail(log, need_bytes); XFS_STATS_INC(xs_sleep_logspace); - sv_wait(&tic->t_wait, PINOD|PLTWAIT, - &log->l_grant_lock, s); - - /* If we're shutting down, this tic is already - * off the queue */ - spin_lock(&log->l_grant_lock); - if (XLOG_FORCED_SHUTDOWN(log)) - goto error_return; - + xlog_wait(&tic->t_wait, &log->l_grant_write_lock); trace_xfs_log_regrant_write_wake1(log, tic); - } + } else + spin_unlock(&log->l_grant_write_lock); } redo: if (XLOG_FORCED_SHUTDOWN(log)) - goto error_return; + goto error_return_unlocked; - free_bytes = xlog_space_left(log, log->l_grant_write_cycle, - log->l_grant_write_bytes); + free_bytes = xlog_space_left(log, &log->l_grant_write_head); if (free_bytes < need_bytes) { - if ((tic->t_flags & XLOG_TIC_IN_Q) == 0) - xlog_ins_ticketq(&log->l_write_headq, tic); - spin_unlock(&log->l_grant_lock); - xlog_grant_push_ail(log->l_mp, need_bytes); - spin_lock(&log->l_grant_lock); - - XFS_STATS_INC(xs_sleep_logspace); - trace_xfs_log_regrant_write_sleep2(log, tic); - - sv_wait(&tic->t_wait, PINOD|PLTWAIT, &log->l_grant_lock, s); + spin_lock(&log->l_grant_write_lock); + if (list_empty(&tic->t_queue)) + list_add_tail(&tic->t_queue, &log->l_writeq); - /* If we're shutting down, this tic is already off the queue */ - spin_lock(&log->l_grant_lock); if (XLOG_FORCED_SHUTDOWN(log)) goto error_return; + xlog_grant_push_ail(log, need_bytes); + + XFS_STATS_INC(xs_sleep_logspace); + trace_xfs_log_regrant_write_sleep2(log, tic); + xlog_wait(&tic->t_wait, &log->l_grant_write_lock); + trace_xfs_log_regrant_write_wake2(log, tic); goto redo; - } else if (tic->t_flags & XLOG_TIC_IN_Q) - xlog_del_ticketq(&log->l_write_headq, tic); + } - /* we've got enough space */ - xlog_grant_add_space_write(log, need_bytes); -#ifdef DEBUG - tail_lsn = log->l_tail_lsn; - if (CYCLE_LSN(tail_lsn) != log->l_grant_write_cycle) { - ASSERT(log->l_grant_write_cycle-1 == CYCLE_LSN(tail_lsn)); - ASSERT(log->l_grant_write_bytes <= BBTOB(BLOCK_LSN(tail_lsn))); + if (!list_empty(&tic->t_queue)) { + spin_lock(&log->l_grant_write_lock); + list_del_init(&tic->t_queue); + spin_unlock(&log->l_grant_write_lock); } -#endif + /* we've got enough space */ + xlog_grant_add_space(log, &log->l_grant_write_head, need_bytes); trace_xfs_log_regrant_write_exit(log, tic); - - xlog_verify_grant_head(log, 1); - spin_unlock(&log->l_grant_lock); + xlog_verify_grant_tail(log); return 0; + error_return_unlocked: + spin_lock(&log->l_grant_write_lock); error_return: - if (tic->t_flags & XLOG_TIC_IN_Q) - xlog_del_ticketq(&log->l_reserve_headq, tic); - + list_del_init(&tic->t_queue); + spin_unlock(&log->l_grant_write_lock); trace_xfs_log_regrant_write_error(log, tic); /* @@ -2778,7 +2714,6 @@ redo: */ tic->t_curr_res = 0; tic->t_cnt = 0; /* ungrant will give back unit_res * t_cnt. */ - spin_unlock(&log->l_grant_lock); return XFS_ERROR(EIO); } /* xlog_regrant_write_log_space */ @@ -2799,27 +2734,24 @@ xlog_regrant_reserve_log_space(xlog_t *log, if (ticket->t_cnt > 0) ticket->t_cnt--; - spin_lock(&log->l_grant_lock); - xlog_grant_sub_space(log, ticket->t_curr_res); + xlog_grant_sub_space(log, &log->l_grant_reserve_head, + ticket->t_curr_res); + xlog_grant_sub_space(log, &log->l_grant_write_head, + ticket->t_curr_res); ticket->t_curr_res = ticket->t_unit_res; xlog_tic_reset_res(ticket); trace_xfs_log_regrant_reserve_sub(log, ticket); - xlog_verify_grant_head(log, 1); - /* just return if we still have some of the pre-reserved space */ - if (ticket->t_cnt > 0) { - spin_unlock(&log->l_grant_lock); + if (ticket->t_cnt > 0) return; - } - xlog_grant_add_space_reserve(log, ticket->t_unit_res); + xlog_grant_add_space(log, &log->l_grant_reserve_head, + ticket->t_unit_res); trace_xfs_log_regrant_reserve_exit(log, ticket); - xlog_verify_grant_head(log, 0); - spin_unlock(&log->l_grant_lock); ticket->t_curr_res = ticket->t_unit_res; xlog_tic_reset_res(ticket); } /* xlog_regrant_reserve_log_space */ @@ -2843,28 +2775,29 @@ STATIC void xlog_ungrant_log_space(xlog_t *log, xlog_ticket_t *ticket) { + int bytes; + if (ticket->t_cnt > 0) ticket->t_cnt--; - spin_lock(&log->l_grant_lock); trace_xfs_log_ungrant_enter(log, ticket); - - xlog_grant_sub_space(log, ticket->t_curr_res); - trace_xfs_log_ungrant_sub(log, ticket); - /* If this is a permanent reservation ticket, we may be able to free + /* + * If this is a permanent reservation ticket, we may be able to free * up more space based on the remaining count. */ + bytes = ticket->t_curr_res; if (ticket->t_cnt > 0) { ASSERT(ticket->t_flags & XLOG_TIC_PERM_RESERV); - xlog_grant_sub_space(log, ticket->t_unit_res*ticket->t_cnt); + bytes += ticket->t_unit_res*ticket->t_cnt; } + xlog_grant_sub_space(log, &log->l_grant_reserve_head, bytes); + xlog_grant_sub_space(log, &log->l_grant_write_head, bytes); + trace_xfs_log_ungrant_exit(log, ticket); - xlog_verify_grant_head(log, 1); - spin_unlock(&log->l_grant_lock); xfs_log_move_tail(log->l_mp, 1); } /* xlog_ungrant_log_space */ @@ -2901,11 +2834,11 @@ xlog_state_release_iclog( if (iclog->ic_state == XLOG_STATE_WANT_SYNC) { /* update tail before writing to iclog */ - xlog_assign_tail_lsn(log->l_mp); + xfs_lsn_t tail_lsn = xlog_assign_tail_lsn(log->l_mp); sync++; iclog->ic_state = XLOG_STATE_SYNCING; - iclog->ic_header.h_tail_lsn = cpu_to_be64(log->l_tail_lsn); - xlog_verify_tail_lsn(log, iclog, log->l_tail_lsn); + iclog->ic_header.h_tail_lsn = cpu_to_be64(tail_lsn); + xlog_verify_tail_lsn(log, iclog, tail_lsn); /* cycle incremented when incrementing curr_block */ } spin_unlock(&log->l_icloglock); @@ -3088,7 +3021,7 @@ maybe_sleep: return XFS_ERROR(EIO); } XFS_STATS_INC(xs_log_force_sleep); - sv_wait(&iclog->ic_force_wait, PINOD, &log->l_icloglock, s); + xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); /* * No need to grab the log lock here since we're * only deciding whether or not to return EIO @@ -3206,8 +3139,8 @@ try_again: XFS_STATS_INC(xs_log_force_sleep); - sv_wait(&iclog->ic_prev->ic_write_wait, - PSWP, &log->l_icloglock, s); + xlog_wait(&iclog->ic_prev->ic_write_wait, + &log->l_icloglock); if (log_flushed) *log_flushed = 1; already_slept = 1; @@ -3235,7 +3168,7 @@ try_again: return XFS_ERROR(EIO); } XFS_STATS_INC(xs_log_force_sleep); - sv_wait(&iclog->ic_force_wait, PSWP, &log->l_icloglock, s); + xlog_wait(&iclog->ic_force_wait, &log->l_icloglock); /* * No need to grab the log lock here since we're * only deciding whether or not to return EIO @@ -3310,10 +3243,8 @@ xfs_log_ticket_put( xlog_ticket_t *ticket) { ASSERT(atomic_read(&ticket->t_ref) > 0); - if (atomic_dec_and_test(&ticket->t_ref)) { - sv_destroy(&ticket->t_wait); + if (atomic_dec_and_test(&ticket->t_ref)) kmem_zone_free(xfs_log_ticket_zone, ticket); - } } xlog_ticket_t * @@ -3435,6 +3366,7 @@ xlog_ticket_alloc( } atomic_set(&tic->t_ref, 1); + INIT_LIST_HEAD(&tic->t_queue); tic->t_unit_res = unit_bytes; tic->t_curr_res = unit_bytes; tic->t_cnt = cnt; @@ -3445,7 +3377,7 @@ xlog_ticket_alloc( tic->t_trans_type = 0; if (xflags & XFS_LOG_PERM_RESERV) tic->t_flags |= XLOG_TIC_PERM_RESERV; - sv_init(&tic->t_wait, SV_DEFAULT, "logtick"); + init_waitqueue_head(&tic->t_wait); xlog_tic_reset_res(tic); @@ -3484,18 +3416,25 @@ xlog_verify_dest_ptr( } STATIC void -xlog_verify_grant_head(xlog_t *log, int equals) +xlog_verify_grant_tail( + struct log *log) { - if (log->l_grant_reserve_cycle == log->l_grant_write_cycle) { - if (equals) - ASSERT(log->l_grant_reserve_bytes >= log->l_grant_write_bytes); - else - ASSERT(log->l_grant_reserve_bytes > log->l_grant_write_bytes); - } else { - ASSERT(log->l_grant_reserve_cycle-1 == log->l_grant_write_cycle); - ASSERT(log->l_grant_write_bytes >= log->l_grant_reserve_bytes); - } -} /* xlog_verify_grant_head */ + int tail_cycle, tail_blocks; + int cycle, space; + + /* + * Check to make sure the grant write head didn't just over lap the + * tail. If the cycles are the same, we can't be overlapping. + * Otherwise, make sure that the cycles differ by exactly one and + * check the byte count. + */ + xlog_crack_grant_head(&log->l_grant_write_head, &cycle, &space); + xlog_crack_atomic_lsn(&log->l_tail_lsn, &tail_cycle, &tail_blocks); + if (tail_cycle != cycle) { + ASSERT(cycle - 1 == tail_cycle); + ASSERT(space <= BBTOB(tail_blocks)); + } +} /* check if it will fit */ STATIC void @@ -3716,12 +3655,10 @@ xfs_log_force_umount( xlog_cil_force(log); /* - * We must hold both the GRANT lock and the LOG lock, - * before we mark the filesystem SHUTDOWN and wake - * everybody up to tell the bad news. + * mark the filesystem and the as in a shutdown state and wake + * everybody up to tell them the bad news. */ spin_lock(&log->l_icloglock); - spin_lock(&log->l_grant_lock); mp->m_flags |= XFS_MOUNT_FS_SHUTDOWN; if (mp->m_sb_bp) XFS_BUF_DONE(mp->m_sb_bp); @@ -3742,27 +3679,21 @@ xfs_log_force_umount( spin_unlock(&log->l_icloglock); /* - * We don't want anybody waiting for log reservations - * after this. That means we have to wake up everybody - * queued up on reserve_headq as well as write_headq. - * In addition, we make sure in xlog_{re}grant_log_space - * that we don't enqueue anything once the SHUTDOWN flag - * is set, and this action is protected by the GRANTLOCK. + * We don't want anybody waiting for log reservations after this. That + * means we have to wake up everybody queued up on reserveq as well as + * writeq. In addition, we make sure in xlog_{re}grant_log_space that + * we don't enqueue anything once the SHUTDOWN flag is set, and this + * action is protected by the grant locks. */ - if ((tic = log->l_reserve_headq)) { - do { - sv_signal(&tic->t_wait); - tic = tic->t_next; - } while (tic != log->l_reserve_headq); - } - - if ((tic = log->l_write_headq)) { - do { - sv_signal(&tic->t_wait); - tic = tic->t_next; - } while (tic != log->l_write_headq); - } - spin_unlock(&log->l_grant_lock); + spin_lock(&log->l_grant_reserve_lock); + list_for_each_entry(tic, &log->l_reserveq, t_queue) + wake_up(&tic->t_wait); + spin_unlock(&log->l_grant_reserve_lock); + + spin_lock(&log->l_grant_write_lock); + list_for_each_entry(tic, &log->l_writeq, t_queue) + wake_up(&tic->t_wait); + spin_unlock(&log->l_grant_write_lock); if (!(log->l_iclog->ic_state & XLOG_STATE_IOERROR)) { ASSERT(!logerror); |