From: Bobi Jam <bobijam.xu@xxxxxxxxx> When a read ahead does not reach the end of the region reserved from ras, we'd set ras::ras_next_readahead back to where we left off; For stride read ahead, it needs to make sure that the offset is no less than ras_stride_offset, so that the stride read ahead can work correctly. Signed-off-by: Bobi Jam <bobijam.xu@xxxxxxxxx> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-5263 Reviewed-on: http://review.whamcloud.com/11181 Reviewed-by: Fan Yong <fan.yong@xxxxxxxxx> Reviewed-by: wang di <di.wang@xxxxxxxxx> Reviewed-by: Oleg Drokin <oleg.drokin@xxxxxxxxx> Signed-off-by: James Simmons <jsimmons@xxxxxxxxxxxxx> --- drivers/staging/lustre/lustre/llite/rw.c | 18 +++++++++++++++--- 1 files changed, 15 insertions(+), 3 deletions(-) diff --git a/drivers/staging/lustre/lustre/llite/rw.c b/drivers/staging/lustre/lustre/llite/rw.c index 25de3bf..de20b7d 100644 --- a/drivers/staging/lustre/lustre/llite/rw.c +++ b/drivers/staging/lustre/lustre/llite/rw.c @@ -413,7 +413,7 @@ static int ll_read_ahead_pages(const struct lu_env *env, * forward read-ahead, it will be fixed when backward * read-ahead is implemented */ - LASSERTF(page_idx > ria->ria_stoff, "Invalid page_idx %lu rs %lu re %lu ro %lu rl %lu rp %lu\n", + LASSERTF(page_idx >= ria->ria_stoff, "Invalid page_idx %lu rs %lu re %lu ro %lu rl %lu rp %lu\n", page_idx, ria->ria_start, ria->ria_end, ria->ria_stoff, ria->ria_length, ria->ria_pages); @@ -474,10 +474,22 @@ int ll_readahead(const struct lu_env *env, struct cl_io *io, } /* Reserve a part of the read-ahead window that we'll be issuing */ - if (ras->ras_window_len) { - start = ras->ras_next_readahead; + if (ras->ras_window_len > 0) { + /* + * Note: other thread might rollback the ras_next_readahead, + * if it can not get the full size of prepared pages, see the + * end of this function. For stride read ahead, it needs to + * make sure the offset is no less than ras_stride_offset, + * so that stride read ahead can work correctly. + */ + if (stride_io_mode(ras)) + start = max(ras->ras_next_readahead, + ras->ras_stride_offset); + else + start = ras->ras_next_readahead; end = ras->ras_window_start + ras->ras_window_len - 1; } + if (end != 0) { unsigned long rpc_boundary; /* -- 1.7.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
