xen/grant-table: log the lack of grants
authorWengang Wang <wen.gang.wang@oracle.com>
Tue, 18 Jul 2017 07:40:35 +0000 (09:40 +0200)
committerJuergen Gross <jgross@suse.com>
Sun, 23 Jul 2017 06:09:43 +0000 (08:09 +0200)
commit29d11cfd8698038b87458ba4d1329b9da81150a5
tree916c500fd8617537daafa63975da37b9d5f713b9
parent0e4d394fe50308f69eb061eb89de78279df1e9dc
xen/grant-table: log the lack of grants

log a message when we enter this situation:
1) we already allocated the max number of available grants from hypervisor
and
2) we still need more (but the request fails because of 1)).

Sometimes the lack of grants causes IO hangs in xen_blkfront devices.
Adding this log would help debuging.

Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Reviewed-by: Junxiao Bi <junxiao.bi@oracle.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Juergen Gross <jgross@suse.com>
drivers/xen/grant-table.c