Messages in this thread | | | From | Dexuan Cui <> | Subject | RE: [PATCH 1/3] scsi: storvsc: Fix max_outstanding_req_per_channel for Win8 and newer | Date | Thu, 17 Dec 2020 21:31:15 +0000 |
| |
> From: Andrea Parri (Microsoft) <parri.andrea@gmail.com> > Sent: Thursday, December 17, 2020 12:33 PM > > Current code overestimates the value of max_outstanding_req_per_channel > for Win8 and newer hosts, since vmscsi_size_delta is set to the initial > value of sizeof(vmscsi_win8_extension) rather than zero. This may lead > to wrong decisions when using ring_avail_percent_lowater equals to zero. > The estimate of max_outstanding_req_per_channel is 'exact' for Win7 and > older hosts. A better choice, keeping the algorithm for the estimation > simple, is to err the other way around, i.e., to underestimate for Win7 > and older but to use the exact value for Win8 and newer. > > Suggested-by: Dexuan Cui <decui@microsoft.com> > Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@gmail.com> > Cc: "James E.J. Bottomley" <jejb@linux.ibm.com> > Cc: "Martin K. Petersen" <martin.petersen@oracle.com> > Cc: linux-scsi@vger.kernel.org
Reviewed-by: Dexuan Cui <decui@microsoft.com>
| |