From b4d2e39d8cfad9fe9585dd6b2382d1261122f22f Mon Sep 17 00:00:00 2001 From: cinap_lenrek Date: Sat, 28 Jul 2012 19:17:54 +0200 Subject: ndb/cs/dns: make sure never to block the 9p loop when we run out of processes, fail the request instead --- sys/src/cmd/ndb/cs.c | 4 ++++ sys/src/cmd/ndb/dnresolve.c | 8 ++++++-- 2 files changed, 10 insertions(+), 2 deletions(-) diff --git a/sys/src/cmd/ndb/cs.c b/sys/src/cmd/ndb/cs.c index 32bccff85..2cd385ed0 100644 --- a/sys/src/cmd/ndb/cs.c +++ b/sys/src/cmd/ndb/cs.c @@ -1654,6 +1654,10 @@ dnsiplookup(char *host, Ndbs *s) qunlock(&dblock); slave(host); + if(*isslave == 0){ + qlock(&dblock); + return nil; + } if(strcmp(ipattr(host), "ip") == 0) t = dnsquery(mntpt, host, "ptr"); diff --git a/sys/src/cmd/ndb/dnresolve.c b/sys/src/cmd/ndb/dnresolve.c index f5954a992..e99177d7d 100644 --- a/sys/src/cmd/ndb/dnresolve.c +++ b/sys/src/cmd/ndb/dnresolve.c @@ -1603,11 +1603,15 @@ netquery(Query *qp, int depth) return Answnone; slave(qp->req); + /* * slave might have forked. if so, the parent process longjmped to * req->mret; we're usually the child slave, but if there are too - * many children already, we're still the same process. + * many children already, we're still the same process. under no + * circumstances block the 9p loop. */ + if(!qp->req->isslave && strcmp(qp->req->from, "9p") == 0) + return Answnone; /* * don't lock before call to slave so only children can block. @@ -1636,7 +1640,7 @@ netquery(Query *qp, int depth) " dropping this one; no further logging" " of drops", dp->name); } - return 0; + return Answnone; } ++qlp->Ref.ref; qunlock(qlp); -- cgit v1.2.3