On Mar 1, 2018, at 16:31, NeilBrown <ne...@suse.com> wrote:
>
> The lustre-release patch commit bdc5bb52c554 ("LU-4933 osc:
> Automatically increase the max_dirty_mb") changed
>
> - if (cli->cl_dirty + PAGE_CACHE_SIZE <= cli->cl_dirty_max &&
> + if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
>
> When this patch landed in Linux a couple of years later, it landed as
>
> - if (cli->cl_dirty + PAGE_SIZE <= cli->cl_dirty_max &&
> + if (cli->cl_dirty_pages <= cli->cl_dirty_max_pages &&
>
> which is clearly different ('<=' vs '<'), and allows cl_dirty_pages to
> increase beyond cl_dirty_max_pages - which causes a latter assertion
> to fails.
>
> Fixes: 3147b268400a ("staging: lustre: osc: Automatically increase the
> max_dirty_mb")
> Signed-off-by: NeilBrown <ne...@suse.com>
Reviewed-by: Andreas Dilger <andreas.dil...@intel.com>
> ---
> drivers/staging/lustre/lustre/include/obd.h | 2 +-
> drivers/staging/lustre/lustre/osc/osc_cache.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/staging/lustre/lustre/include/obd.h
> b/drivers/staging/lustre/lustre/include/obd.h
> index 4368f4e9f208..f1233ca7d337 100644
> --- a/drivers/staging/lustre/lustre/include/obd.h
> +++ b/drivers/staging/lustre/lustre/include/obd.h
> @@ -191,7 +191,7 @@ struct client_obd {
> struct sptlrpc_flavor cl_flvr_mgc; /* fixed flavor of mgc->mgs */
>
> /* the grant values are protected by loi_list_lock below */
> - unsigned long cl_dirty_pages; /* all _dirty_ in
> pahges */
> + unsigned long cl_dirty_pages; /* all _dirty_ in pages
> */
> unsigned long cl_dirty_max_pages; /* allowed w/o rpc */
> unsigned long cl_dirty_transit; /* dirty synchronous */
> unsigned long cl_avail_grant; /* bytes of credit for
> ost */
> diff --git a/drivers/staging/lustre/lustre/osc/osc_cache.c
> b/drivers/staging/lustre/lustre/osc/osc_cache.c
> index 1c70a504ee89..459503727ce3 100644
> --- a/drivers/staging/lustre/lustre/osc/osc_cache.c
> +++ b/drivers/staging/lustre/lustre/osc/osc_cache.c
> @@ -1529,7 +1529,7 @@ static int osc_enter_cache_try(struct client_obd *cli,
> if (rc < 0)
> return 0;
>
> - if (cli->cl_dirty_pages <= cli->cl_dirty_max_pages &&
> + if (cli->cl_dirty_pages < cli->cl_dirty_max_pages &&
> atomic_long_read(&obd_dirty_pages) + 1 <= obd_max_dirty_pages) {
> osc_consume_write_grant(cli, &oap->oap_brw_page);
> if (transient) {
>
>
Cheers, Andreas
--
Andreas Dilger
Lustre Principal Architect
Intel Corporation
