[LU-14543] tgt_grant_discard(): avoid tgd->tgd_tot_granted overflowing

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.12.8, Lustre 2.15.0
• Severity: 3
• Assignee: Vladimir Saveliev
• Reporter: Vladimir Saveliev

Description

void tgt_grant_discard(struct obd_export *exp)
...
        if (tgd->tgd_tot_granted < ted->ted_grant) {
                CERROR("%s: tot_granted %llu < cli %s/%p ted_grant %ld\n",
                       obd->obd_name, tgd->tgd_tot_granted,
                       exp->exp_client_uuid.uuid, exp, ted->ted_grant);
        }
        tgd->tgd_tot_granted -= ted->ted_grant;
...

If tgd->tgd_tot_granted < ted->ted_grant the decrement makes tgd_tot_granted too big.

Issue Links

• is related to: LU-15095 lctl: error invoking upcall /usr/sbin/lctl set_param *.*.lbug_on_grant_miscount=1
• is related to: LU-14125 client starved for grant but OST has plenty of free space