staging: lustre: fix bug in osc_enter_cache_try

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: 3147b26840 ("staging: lustre: osc: Automatically increase the max_dirty_mb")
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
NeilBrown 2018-03-02 10:31:25 +11:00 committed by Greg Kroah-Hartman
parent 436630983b
commit 2fab9faf9b
2 changed files with 2 additions and 2 deletions

View File

@ -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 */

View File

@ -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) {