From: Bobi Jam <bobijam...@intel.com> It is possible that an osc_extent contains more than 256 chunks, and the IO engine won't add this extent in one RPC (try_to_add_extent_for_io) so that osc_check_rpcs() run into a loop upon this extent and never break.
This patch changes osc_max_write_chunks() to make sure the value can cover all possible osc_extent, so that all osc_extent will be added into one RPC. This patch also add another field erd_max_extents in extent_rpc_data to make sure not to add too many fragments in a single RPC. Signed-off-by: Bobi Jam <bobijam...@intel.com> Intel-bug-id: https://jira.hpdd.intel.com/browse/LU-8680 Reviewed-on: http://review.whamcloud.com/23326 Reviewed-by: Jinshan Xiong <jinshan.xi...@intel.com> Reviewed-by: Niu Yawei <yawei....@intel.com> Reviewed-by: Oleg Drokin <oleg.dro...@intel.com> Signed-off-by: James Simmons <jsimm...@infradead.org> --- drivers/staging/lustre/lustre/osc/osc_cache.c | 24 +++++++++++++++++++++--- 1 file changed, 21 insertions(+), 3 deletions(-) diff --git a/drivers/staging/lustre/lustre/osc/osc_cache.c b/drivers/staging/lustre/lustre/osc/osc_cache.c index d8a95f8..0100d27 100644 --- a/drivers/staging/lustre/lustre/osc/osc_cache.c +++ b/drivers/staging/lustre/lustre/osc/osc_cache.c @@ -1887,6 +1887,7 @@ struct extent_rpc_data { unsigned int erd_page_count; unsigned int erd_max_pages; unsigned int erd_max_chunks; + unsigned int erd_max_extents; }; static inline unsigned int osc_extent_chunks(const struct osc_extent *ext) @@ -1915,11 +1916,23 @@ static int try_to_add_extent_for_io(struct client_obd *cli, EASSERT((ext->oe_state == OES_CACHE || ext->oe_state == OES_LOCK_DONE), ext); + if (!data->erd_max_extents) + return 0; + chunk_count = osc_extent_chunks(ext); + EASSERTF(data->erd_page_count != 0 || + chunk_count <= data->erd_max_chunks, ext, + "The first extent to be fit in a RPC contains %u chunks, which is over the limit %u.\n", + chunk_count, data->erd_max_chunks); + if (chunk_count > data->erd_max_chunks) return 0; data->erd_max_pages = max(ext->oe_mppr, data->erd_max_pages); + EASSERTF(data->erd_page_count != 0 || + ext->oe_nr_pages <= data->erd_max_pages, ext, + "The first extent to be fit in a RPC contains %u pages, which is over the limit %u.\n", + ext->oe_nr_pages, data->erd_max_pages); if (data->erd_page_count + ext->oe_nr_pages > data->erd_max_pages) return 0; @@ -1943,6 +1956,7 @@ static int try_to_add_extent_for_io(struct client_obd *cli, break; } + data->erd_max_extents--; data->erd_max_chunks -= chunk_count; data->erd_page_count += ext->oe_nr_pages; list_move_tail(&ext->oe_link, data->erd_rpc_list); @@ -1972,10 +1986,12 @@ static inline unsigned int osc_max_write_chunks(const struct client_obd *cli) * * This limitation doesn't apply to ldiskfs, which allows as many * chunks in one RPC as we want. However, it won't have any benefits - * to have too many discontiguous pages in one RPC. Therefore, it - * can only have 256 chunks at most in one RPC. + * to have too many discontiguous pages in one RPC. + * + * An osc_extent won't cover over a RPC size, so the chunks in an + * osc_extent won't bigger than PTLRPC_MAX_BRW_SIZE >> chunkbits. */ - return min(PTLRPC_MAX_BRW_SIZE >> cli->cl_chunkbits, 256); + return PTLRPC_MAX_BRW_SIZE >> cli->cl_chunkbits; } /** @@ -2002,6 +2018,7 @@ static unsigned int get_write_extents(struct osc_object *obj, .erd_page_count = 0, .erd_max_pages = cli->cl_max_pages_per_rpc, .erd_max_chunks = osc_max_write_chunks(cli), + .erd_max_extents = 256, }; LASSERT(osc_object_is_locked(obj)); @@ -2140,6 +2157,7 @@ static unsigned int get_write_extents(struct osc_object *obj, .erd_page_count = 0, .erd_max_pages = cli->cl_max_pages_per_rpc, .erd_max_chunks = UINT_MAX, + .erd_max_extents = UINT_MAX, }; int rc = 0; -- 1.8.3.1 _______________________________________________ devel mailing list de...@linuxdriverproject.org http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel
