diff options
Diffstat (limited to 'fs/xfs/xfs_log_cil.c')
-rw-r--r-- | fs/xfs/xfs_log_cil.c | 55 |
1 files changed, 42 insertions, 13 deletions
diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c index 8a83d901e465..880ea9536f82 100644 --- a/fs/xfs/xfs_log_cil.c +++ b/fs/xfs/xfs_log_cil.c @@ -44,9 +44,20 @@ xlog_cil_ticket_alloc( * transaction overhead reservation from the first transaction commit. */ tic->t_curr_res = 0; + tic->t_iclog_hdrs = 0; return tic; } +static inline void +xlog_cil_set_iclog_hdr_count(struct xfs_cil *cil) +{ + struct xlog *log = cil->xc_log; + + atomic_set(&cil->xc_iclog_hdrs, + (XLOG_CIL_BLOCKING_SPACE_LIMIT(log) / + (log->l_iclog_size - log->l_iclog_hsize))); +} + /* * Check if the current log item was first committed in this sequence. * We can't rely on just the log item being in the CIL, we have to check @@ -102,6 +113,7 @@ xlog_cil_ctx_switch( struct xfs_cil *cil, struct xfs_cil_ctx *ctx) { + xlog_cil_set_iclog_hdr_count(cil); set_bit(XLOG_CIL_EMPTY, &cil->xc_flags); ctx->sequence = ++cil->xc_current_sequence; ctx->cil = cil; @@ -124,6 +136,7 @@ xlog_cil_init_post_recovery( { log->l_cilp->xc_ctx->ticket = xlog_cil_ticket_alloc(log); log->l_cilp->xc_ctx->sequence = 1; + xlog_cil_set_iclog_hdr_count(log->l_cilp); } static inline int @@ -451,7 +464,6 @@ xlog_cil_insert_items( struct xfs_cil_ctx *ctx = cil->xc_ctx; struct xfs_log_item *lip; int len = 0; - int iclog_space; int iovhdr_res = 0, split_res = 0, ctx_res = 0; ASSERT(tp); @@ -474,19 +486,36 @@ xlog_cil_insert_items( test_and_clear_bit(XLOG_CIL_EMPTY, &cil->xc_flags)) ctx_res = ctx->ticket->t_unit_res; - spin_lock(&cil->xc_cil_lock); - - /* do we need space for more log record headers? */ - iclog_space = log->l_iclog_size - log->l_iclog_hsize; - if (len > 0 && (ctx->space_used / iclog_space != - (ctx->space_used + len) / iclog_space)) { - split_res = (len + iclog_space - 1) / iclog_space; - /* need to take into account split region headers, too */ - split_res *= log->l_iclog_hsize + sizeof(struct xlog_op_header); - ctx->ticket->t_unit_res += split_res; + /* + * Check if we need to steal iclog headers. atomic_read() is not a + * locked atomic operation, so we can check the value before we do any + * real atomic ops in the fast path. If we've already taken the CIL unit + * reservation from this commit, we've already got one iclog header + * space reserved so we have to account for that otherwise we risk + * overrunning the reservation on this ticket. + * + * If the CIL is already at the hard limit, we might need more header + * space that originally reserved. So steal more header space from every + * commit that occurs once we are over the hard limit to ensure the CIL + * push won't run out of reservation space. + * + * This can steal more than we need, but that's OK. + */ + if (atomic_read(&cil->xc_iclog_hdrs) > 0 || + ctx->space_used + len >= XLOG_CIL_BLOCKING_SPACE_LIMIT(log)) { + int split_res = log->l_iclog_hsize + + sizeof(struct xlog_op_header); + if (ctx_res) + ctx_res += split_res * (tp->t_ticket->t_iclog_hdrs - 1); + else + ctx_res = split_res * tp->t_ticket->t_iclog_hdrs; + atomic_sub(tp->t_ticket->t_iclog_hdrs, &cil->xc_iclog_hdrs); } - tp->t_ticket->t_curr_res -= split_res + ctx_res + len; - ctx->ticket->t_curr_res += split_res + ctx_res; + + spin_lock(&cil->xc_cil_lock); + tp->t_ticket->t_curr_res -= ctx_res + len; + ctx->ticket->t_unit_res += ctx_res; + ctx->ticket->t_curr_res += ctx_res; ctx->space_used += len; tp->t_ticket->t_curr_res += released_space; |