ntohs(thishost->port)));
cb->status = CB_DELAYED;
} else {
- h_Hold_r(thishost);
- cba[ncbas].hp = thishost;
- cba[ncbas].thead = cb->thead;
- ncbas++;
+ if (!(thishost->hostFlags & HOSTDELETED)) {
+ h_Hold_r(thishost);
+ cba[ncbas].hp = thishost;
+ cba[ncbas].thead = cb->thead;
+ ncbas++;
+ }
TDel(cb);
HDel(cb);
CDel(cb, 1); /* Usually first; so this delete
register struct CallBack *cbnext;
for (cb = itocb(fe->firstcb); cb; cb = cbnext) {
host = h_itoh(cb->hhead);
- h_Hold_r(host);
- cbnext = itocb(cb->cnext);
- if (!tthead || (TNorm(tthead) < TNorm(cb->thead))) {
- tthead = cb->thead;
+
+ if (!(host->hostFlags & HOSTDELETED)) {
+ h_Hold_r(host);
+ if (!tthead || (TNorm(tthead) < TNorm(cb->thead))) {
+ tthead = cb->thead;
+ }
}
+ cbnext = itocb(cb->cnext);
TDel(cb);
HDel(cb);
FreeCB(cb);
cbnext = itocb(cb->cnext);
host = h_itoh(cb->hhead);
if (cb->status == CB_DELAYED) {
- h_Hold_r(host);
- if (!tthead || (TNorm(tthead) < TNorm(cb->thead))) {
- tthead = cb->thead;
+ if (!(host->hostFlags & HOSTDELETED)) {
+ h_Hold_r(host);
+ if (!tthead || (TNorm(tthead) < TNorm(cb->thead))) {
+ tthead = cb->thead;
+ }
}
TDel(cb);
HDel(cb);
return (ntimedout > 0);
}
-static struct host *lih_host;
-static int lih_host_held;
+/**
+ * parameters to pass to lih*_r from h_Enumerate_r when trying to find a host
+ * from which to clear callbacks.
+ */
+struct lih_params {
+ /**
+ * Points to the least interesting host found; try to clear callbacks on
+ * this host after h_Enumerate_r(lih*_r)'ing.
+ */
+ struct host *lih;
+
+ /**
+ * The last host we got from lih*_r, but we couldn't clear its callbacks
+ * for some reason. Choose the next-best host after this one (with the
+ * current lih*_r, this means to only select hosts that have an ActiveCall
+ * newer than lastlih).
+ */
+ struct host *lastlih;
+};
/* Value of host->refCount that allows us to reliably infer that
* host may be held by some other thread */
#define OTHER_MUSTHOLD_LIH 2
/* This version does not allow 'host' to be selected unless its ActiveCall
- * is newer than 'hostp' which is the host with the oldest ActiveCall from
- * the last pass (if it is provided). We filter out any hosts that are
- * are held by other threads.
+ * is newer than 'params->lastlih' which is the host with the oldest
+ * ActiveCall from the last pass (if it is provided). We filter out any hosts
+ * that are are held by other threads.
+ *
+ * There is a small problem here, but it may not be easily fixable. Say we
+ * select some host A, and give it back to GetSomeSpace_r. GSS_r for some
+ * reason cannot clear the callbacks on A, and so calls us again with
+ * lastlih = A. Suppose there is another host B that has the same ActiveCall
+ * time as A. We will now skip over host B, since
+ * 'hostB->ActiveCall > hostA->ActiveCall' is not true. This could result in
+ * us prematurely going to the GSS_r 2nd or 3rd pass, and making us a little
+ * inefficient. This should be pretty rare, though, except perhaps in cases
+ * with very small numbers of hosts.
+ *
+ * Also filter out any hosts with HOSTDELETED set. h_Enumerate_r should in
+ * theory not give these to us anyway, but be paranoid.
*/
static int
lih0_r(register struct host *host, register int flags, void *rock)
{
- struct host *hostp = (struct host *) rock;
+ struct lih_params *params = (struct lih_params *)rock;
+
if (host->cblist
- && (hostp && host != hostp)
+ && (!(host->hostFlags & HOSTDELETED))
&& (host->refCount < OTHER_MUSTHOLD_LIH)
- && (!lih_host || host->ActiveCall < lih_host->ActiveCall)
- && (!hostp || host->ActiveCall > hostp->ActiveCall)) {
- if (lih_host != NULL && lih_host_held) {
- h_Release_r(lih_host); /* release prev host */
- }
- lih_host = host;
- lih_host_held = !flags; /* on i==1, this === (lih_host_held = 1) */
- flags = 1; /* now flags is 1, but at next(i), it will be 0 again */
+ && (!params->lih || host->ActiveCall < params->lih->ActiveCall)
+ && (!params->lastlih || host->ActiveCall > params->lastlih->ActiveCall)) {
+
+ if (params->lih) {
+ h_Release_r(params->lih); /* release prev host */
+ }
+
+ h_Hold_r(host);
+ params->lih = host;
}
return flags;
}
-/* This version does not allow 'host' to be selected unless its ActiveCall
- * is newer than 'hostp' which is the host with the oldest ActiveCall from
- * the last pass (if it is provided). In this second varient, we do not
- * prevent held hosts from being selected.
- */
+/* same as lih0_r, except we do not prevent held hosts from being selected. */
static int
lih1_r(register struct host *host, register int flags, void *rock)
{
- struct host *hostp = (struct host *) rock;
+ struct lih_params *params = (struct lih_params *)rock;
if (host->cblist
- && (hostp && host != hostp)
- && (!lih_host || host->ActiveCall < lih_host->ActiveCall)
- && (!hostp || host->ActiveCall > hostp->ActiveCall)) {
- if (lih_host != NULL && lih_host_held) {
- h_Release_r(lih_host); /* really? */
- }
- lih_host = host;
- lih_host_held = !flags; /* see note above */
- flags = 1; /* see note above */
+ && (!(host->hostFlags & HOSTDELETED))
+ && (!params->lih || host->ActiveCall < params->lih->ActiveCall)
+ && (!params->lastlih || host->ActiveCall > params->lastlih->ActiveCall)) {
+
+ if (params->lih) {
+ h_Release_r(params->lih); /* release prev host */
+ }
+
+ h_Hold_r(host);
+ params->lih = host;
}
return flags;
}
static int
GetSomeSpace_r(struct host *hostp, int locked)
{
- register struct host *hp, *hp1, *hp2;
+ struct host *hp;
+ struct lih_params params;
int i = 0;
cbstuff.GotSomeSpaces++;
}
i = 0;
- hp1 = NULL;
- hp2 = hostList;
+ params.lastlih = NULL;
+
do {
- lih_host = 0;
- h_Enumerate_r(i == 0 ? lih0_r : lih1_r, hp2, (char *)hp1);
- hp = lih_host;
+ params.lih = NULL;
+
+ h_Enumerate_r(i == 0 ? lih0_r : lih1_r, hostList, ¶ms);
+
+ hp = params.lih;
+ if (params.lastlih) {
+ h_Release_r(params.lastlih);
+ params.lastlih = NULL;
+ }
+
if (hp) {
- /* set in lih_r! private copy before giving up H_LOCK */
- int lih_host_held2=lih_host_held;
+ /* note that 'hp' was held by lih*_r; we will need to release it */
cbstuff.GSS4++;
if ((hp != hostp) && !ClearHostCallbacks_r(hp, 0 /* not locked or held */ )) {
- if (lih_host_held2)
- h_Release_r(hp);
+ h_Release_r(hp);
return 0;
}
- if (lih_host_held2) {
- h_Release_r(hp);
- hp = NULL;
- }
- hp1 = hp;
- hp2 = hostList;
+
+ params.lastlih = hp;
+ /* params.lastlih will be released on the next iteration, after
+ * h_Enumerate_r */
+
} else {
/*
* Next time try getting callbacks from any host even if
- * it's deleted (that's actually great since we can freely
- * remove its callbacks) or it's held since the only other
- * option is starvation for the file server (i.e. until the
- * callback timeout arrives).
+ * it's held, since the only other option is starvation for
+ * the file server (i.e. until the callback timeout arrives).
*/
i++;
- hp1 = NULL;
- hp2 = hostList;
+ params.lastlih = NULL;
cbstuff.GSS1++;
ViceLog(5,
("GSS: Try harder for longest inactive host cnt= %d\n",
("GSS: Delete longest inactive host %p (%s:%d)\n",
hp, afs_inet_ntoa_r(hp->host, hoststr), ntohs(hp->port)));
+ if ((hp->hostFlags & HOSTDELETED)) {
+ /* hp could go away after reacquiring H_LOCK in h_NBLock_r, so we can't
+ * really use it; its callbacks will get cleared anyway when
+ * h_TossStuff_r gets its hands on it */
+ return 1;
+ }
+
h_Hold_r(hp);
/** Try a non-blocking lock. If the lock is already held return
git://git.openafs.org / openafs.git / blobdiff