diff options
Diffstat (limited to 'sys/kern/vfs_subr.c')
| -rw-r--r-- | sys/kern/vfs_subr.c | 21 |
1 files changed, 19 insertions, 2 deletions
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c index 76bd584..059ca2a 100644 --- a/sys/kern/vfs_subr.c +++ b/sys/kern/vfs_subr.c @@ -1208,6 +1208,7 @@ reassignbuf(bp, newvp) tbp = TAILQ_FIRST(listheadp); if (tbp == NULL || bp->b_lblkno == 0 || + (bp->b_lblkno > 0 && tbp->b_lblkno < 0) || (bp->b_lblkno > 0 && bp->b_lblkno < tbp->b_lblkno)) { TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); ++reassignbufsortgood; @@ -1217,14 +1218,30 @@ reassignbuf(bp, newvp) } else if (reassignbufmethod == 1) { /* * New sorting algorithm, only handle sequential case, - * otherwise guess. + * otherwise append to end (but before metadata) */ if ((tbp = gbincore(newvp, bp->b_lblkno - 1)) != NULL && (tbp->b_xflags & BX_VNDIRTY)) { + /* + * Found the best place to insert the buffer + */ TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); ++reassignbufsortgood; } else { - TAILQ_INSERT_HEAD(listheadp, bp, b_vnbufs); + /* + * Missed, append to end, but before meta-data. + * We know that the head buffer in the list is + * not meta-data due to prior conditionals. + * + * Indirect effects: NFS second stage write + * tends to wind up here, giving maximum + * distance between the unstable write and the + * commit rpc. + */ + tbp = TAILQ_LAST(listheadp, buflists); + while (tbp && tbp->b_lblkno < 0) + tbp = TAILQ_PREV(tbp, buflists, b_vnbufs); + TAILQ_INSERT_AFTER(listheadp, tbp, bp, b_vnbufs); ++reassignbufsortbad; } } else { |
