/*
- * Copyright (C) 1996-2017 The Squid Software Foundation and contributors
+ * Copyright (C) 1996-2020 The Squid Software Foundation and contributors
*
* Squid software is distributed under GPLv2+ license and includes
* contributions from numerous individuals and organizations.
static IOCB helperHandleRead;
static IOCB helperStatefulHandleRead;
-static void helperServerFree(helper_server *srv);
-static void helperStatefulServerFree(helper_stateful_server *srv);
static void Enqueue(helper * hlp, Helper::Xaction *);
static helper_server *GetFirstAvailable(const helper * hlp);
-static helper_stateful_server *StatefulGetFirstAvailable(const statefulhelper * hlp);
+static helper_stateful_server *StatefulGetFirstAvailable(statefulhelper * hlp);
static void helperDispatch(helper_server * srv, Helper::Xaction * r);
static void helperStatefulDispatch(helper_stateful_server * srv, Helper::Xaction * r);
static void helperKickQueue(helper * hlp);
#endif
}
+void
+HelperServerBase::dropQueued()
+{
+ while (!requests.empty()) {
+ // XXX: re-schedule these on another helper?
+ Helper::Xaction *r = requests.front();
+ requests.pop_front();
+ void *cbdata;
+ if (cbdataReferenceValidDone(r->request.data, &cbdata)) {
+ r->reply.result = Helper::Unknown;
+ r->request.callback(cbdata, r->reply);
+ }
+
+ delete r;
+ }
+}
+
+HelperServerBase::~HelperServerBase()
+{
+ if (rbuf) {
+ memFreeBuf(rbuf_sz, rbuf);
+ rbuf = NULL;
+ }
+}
+
+helper_server::~helper_server()
+{
+ wqueue->clean();
+ delete wqueue;
+
+ if (writebuf) {
+ writebuf->clean();
+ delete writebuf;
+ writebuf = NULL;
+ }
+
+ if (Comm::IsConnOpen(writePipe))
+ closeWritePipeSafely(parent->id_name);
+
+ dlinkDelete(&link, &parent->servers);
+
+ assert(parent->childs.n_running > 0);
+ -- parent->childs.n_running;
+
+ assert(requests.empty());
+ cbdataReferenceDone(parent);
+}
+
+void
+helper_server::dropQueued()
+{
+ HelperServerBase::dropQueued();
+ requestsIndex.clear();
+}
+
+helper_stateful_server::~helper_stateful_server()
+{
+ /* TODO: walk the local queue of requests and carry them all out */
+ if (Comm::IsConnOpen(writePipe))
+ closeWritePipeSafely(parent->id_name);
+
+ parent->cancelReservation(reservationId);
+
+ dlinkDelete(&link, &parent->servers);
+
+ assert(parent->childs.n_running > 0);
+ -- parent->childs.n_running;
+
+ assert(requests.empty());
+
+ cbdataReferenceDone(parent);
+}
+
void
helperOpenServers(helper * hlp)
{
if (wfd != rfd)
commSetNonBlocking(wfd);
- AsyncCall::Pointer closeCall = asyncCall(5,4, "helperServerFree", cbdataDialer(helperServerFree, srv));
+ AsyncCall::Pointer closeCall = asyncCall(5,4, "helper_server::HelperServerClosed", cbdataDialer(helper_server::HelperServerClosed, srv));
comm_add_close_handler(rfd, closeCall);
if (hlp->timeout && hlp->childs.concurrency) {
helper_stateful_server *srv = new helper_stateful_server;
srv->hIpc = hIpc;
srv->pid = pid;
- srv->flags.reserved = false;
srv->initStats();
srv->addr = hlp->addr;
srv->readPipe = new Comm::Connection;
srv->rbuf = (char *)memAllocBuf(ReadBufSize, &srv->rbuf_sz);
srv->roffset = 0;
srv->parent = cbdataReference(hlp);
-
- if (hlp->datapool != NULL)
- srv->data = hlp->datapool->alloc();
+ srv->reservationStart = 0;
dlinkAddTail(srv, &srv->link, &hlp->servers);
if (wfd != rfd)
commSetNonBlocking(wfd);
- AsyncCall::Pointer closeCall = asyncCall(5,4, "helperStatefulServerFree", cbdataDialer(helperStatefulServerFree, srv));
+ AsyncCall::Pointer closeCall = asyncCall(5,4, "helper_stateful_server::HelperServerClosed", cbdataDialer(helper_stateful_server::HelperServerClosed, srv));
comm_add_close_handler(rfd, closeCall);
AsyncCall::Pointer call = commCbCall(5,4, "helperStatefulHandleRead",
debugs(84, DBG_DATA, Raw("buf", buf, strlen(buf)));
}
-/// lastserver = "server last used as part of a reserved request sequence"
+/// Submit request or callback the caller with a Helper::Error error.
+/// If the reservation is not set then reserves a new helper.
void
-helperStatefulSubmit(statefulhelper * hlp, const char *buf, HLPCB * callback, void *data, helper_stateful_server * lastserver)
+helperStatefulSubmit(statefulhelper * hlp, const char *buf, HLPCB * callback, void *data, const Helper::ReservationId & reservation)
{
- if (!hlp || !hlp->trySubmit(buf, callback, data, lastserver))
+ if (!hlp || !hlp->trySubmit(buf, callback, data, reservation))
SubmissionFailure(hlp, callback, data);
}
/// If possible, submit request. Otherwise, either kill Squid or return false.
bool
-statefulhelper::trySubmit(const char *buf, HLPCB * callback, void *data, helper_stateful_server *lastserver)
+statefulhelper::trySubmit(const char *buf, HLPCB * callback, void *data, const Helper::ReservationId & reservation)
{
if (!prepSubmit())
return false; // request was dropped
- submit(buf, callback, data, lastserver); // will send or queue
+ submit(buf, callback, data, reservation); // will send or queue
return true; // request submitted or queued
}
-void statefulhelper::submit(const char *buf, HLPCB * callback, void *data, helper_stateful_server * lastserver)
+void
+statefulhelper::reserveServer(helper_stateful_server * srv)
{
- Helper::Xaction *r = new Helper::Xaction(callback, data, buf);
+ // clear any old reservation
+ if (srv->reserved()) {
+ reservations.erase(srv->reservationId);
+ srv->clearReservation();
+ }
- if ((buf != NULL) && lastserver) {
- debugs(84, 5, "StatefulSubmit with lastserver " << lastserver);
- assert(lastserver->flags.reserved);
- assert(!lastserver->requests.size());
+ srv->reserve();
+ reservations.insert(Reservations::value_type(srv->reservationId, srv));
+}
+
+void
+statefulhelper::cancelReservation(const Helper::ReservationId reservation)
+{
+ const auto it = reservations.find(reservation);
+ if (it == reservations.end())
+ return;
+
+ helper_stateful_server *srv = it->second;
+ reservations.erase(it);
+ srv->clearReservation();
+
+ // schedule a queue kick
+ AsyncCall::Pointer call = asyncCall(5,4, "helperStatefulServerDone", cbdataDialer(helperStatefulServerDone, srv));
+ ScheduleCallHere(call);
+}
+helper_stateful_server *
+statefulhelper::findServer(const Helper::ReservationId & reservation)
+{
+ const auto it = reservations.find(reservation);
+ if (it == reservations.end())
+ return nullptr;
+ return it->second;
+}
+
+void
+helper_stateful_server::reserve()
+{
+ assert(!reservationId);
+ reservationStart = squid_curtime;
+ reservationId = Helper::ReservationId::Next();
+ debugs(84, 3, "srv-" << index << " reservation id = " << reservationId);
+}
+
+void
+helper_stateful_server::clearReservation()
+{
+ debugs(84, 3, "srv-" << index << " reservation id = " << reservationId);
+ if (!reservationId)
+ return;
+
+ ++stats.releases;
+
+ reservationId.clear();
+ reservationStart = 0;
+}
+
+void
+statefulhelper::submit(const char *buf, HLPCB * callback, void *data, const Helper::ReservationId & reservation)
+{
+ Helper::Xaction *r = new Helper::Xaction(callback, data, buf);
+
+ if (buf && reservation) {
+ debugs(84, 5, reservation);
+ helper_stateful_server *lastServer = findServer(reservation);
+ if (!lastServer) {
+ debugs(84, DBG_CRITICAL, "ERROR: Helper " << id_name << " reservation expired (" << reservation << ")");
+ r->reply.result = Helper::TimedOut;
+ r->request.callback(r->request.data, r->reply);
+ delete r;
+ return;
+ }
debugs(84, 5, "StatefulSubmit dispatching");
- helperStatefulDispatch(lastserver, r);
+ helperStatefulDispatch(lastServer, r);
} else {
helper_stateful_server *srv;
if ((srv = StatefulGetFirstAvailable(this))) {
+ reserveServer(srv);
helperStatefulDispatch(srv, r);
} else
StatefulEnqueue(this, r);
syncQueueStats();
}
-/**
- * DPW 2007-05-08
- *
- * helperStatefulReleaseServer tells the helper that whoever was
- * using it no longer needs its services.
- */
-void
-helperStatefulReleaseServer(helper_stateful_server * srv)
-{
- debugs(84, 3, HERE << "srv-" << srv->index << " flags.reserved = " << srv->flags.reserved);
- if (!srv->flags.reserved)
- return;
-
- ++ srv->stats.releases;
-
- srv->flags.reserved = false;
-
- helperStatefulServerDone(srv);
-}
-
-/** return a pointer to the stateful routines data area */
-void *
-helperStatefulServerGetData(helper_stateful_server * srv)
-{
- return srv->data;
-}
-
void
helper::packStatsInto(Packable *p, const char *label) const
{
srv->stats.pending ? 'B' : ' ',
srv->flags.writing ? 'W' : ' ',
srv->flags.closing ? 'C' : ' ',
- srv->flags.reserved ? 'R' : ' ',
+ srv->reserved() ? 'R' : ' ',
srv->flags.shutdown ? 'S' : ' ',
xaction && xaction->request.placeholder ? 'P' : ' ',
tt < 0.0 ? 0.0 : tt,
continue;
}
- if (srv->flags.reserved) {
+ if (srv->reserved()) {
if (shutting_down) {
debugs(84, 3, "helperStatefulShutdown: " << hlp->id_name << " #" << srv->index << " is RESERVED. Closing anyway.");
} else {
debugs(84, DBG_CRITICAL, "WARNING: freeing " << id_name << " helper with " << stats.queue_size << " requests queued");
}
-/* ====================================================================== */
-/* LOCAL FUNCTIONS */
-/* ====================================================================== */
-
-static void
-helperServerFree(helper_server *srv)
+void
+helper::handleKilledServer(HelperServerBase *srv, bool &needsNewServers)
{
- helper *hlp = srv->parent;
- int concurrency = hlp->childs.concurrency;
-
- if (!concurrency)
- concurrency = 1;
-
- if (srv->rbuf) {
- memFreeBuf(srv->rbuf_sz, srv->rbuf);
- srv->rbuf = NULL;
- }
-
- srv->wqueue->clean();
- delete srv->wqueue;
-
- if (srv->writebuf) {
- srv->writebuf->clean();
- delete srv->writebuf;
- srv->writebuf = NULL;
- }
-
- if (Comm::IsConnOpen(srv->writePipe))
- srv->closeWritePipeSafely(hlp->id_name);
-
- dlinkDelete(&srv->link, &hlp->servers);
-
- assert(hlp->childs.n_running > 0);
- -- hlp->childs.n_running;
-
+ needsNewServers = false;
if (!srv->flags.shutdown) {
- assert(hlp->childs.n_active > 0);
- -- hlp->childs.n_active;
- debugs(84, DBG_CRITICAL, "WARNING: " << hlp->id_name << " #" << srv->index << " exited");
+ assert(childs.n_active > 0);
+ --childs.n_active;
+ debugs(84, DBG_CRITICAL, "WARNING: " << id_name << " #" << srv->index << " exited");
- if (hlp->childs.needNew() > 0) {
- debugs(80, DBG_IMPORTANT, "Too few " << hlp->id_name << " processes are running (need " << hlp->childs.needNew() << "/" << hlp->childs.n_max << ")");
+ if (childs.needNew() > 0) {
+ debugs(80, DBG_IMPORTANT, "Too few " << id_name << " processes are running (need " << childs.needNew() << "/" << childs.n_max << ")");
- if (hlp->childs.n_active < hlp->childs.n_startup && hlp->last_restart > squid_curtime - 30) {
+ if (childs.n_active < childs.n_startup && last_restart > squid_curtime - 30) {
if (srv->stats.replies < 1)
- fatalf("The %s helpers are crashing too rapidly, need help!\n", hlp->id_name);
+ fatalf("The %s helpers are crashing too rapidly, need help!\n", id_name);
else
- debugs(80, DBG_CRITICAL, "ERROR: The " << hlp->id_name << " helpers are crashing too rapidly, need help!");
+ debugs(80, DBG_CRITICAL, "ERROR: The " << id_name << " helpers are crashing too rapidly, need help!");
}
-
- debugs(80, DBG_IMPORTANT, "Starting new helpers");
- helperOpenServers(hlp);
- }
- }
-
- while (!srv->requests.empty()) {
- // XXX: re-schedule these on another helper?
- Helper::Xaction *r = srv->requests.front();
- srv->requests.pop_front();
- void *cbdata;
-
- if (cbdataReferenceValidDone(r->request.data, &cbdata)) {
- r->reply.result = Helper::Unknown;
- r->request.callback(cbdata, r->reply);
+ srv->flags.shutdown = true;
+ needsNewServers = true;
}
-
- delete r;
}
- srv->requestsIndex.clear();
-
- cbdataReferenceDone(srv->parent);
- delete srv;
}
-static void
-helperStatefulServerFree(helper_stateful_server *srv)
+void
+helper_server::HelperServerClosed(helper_server *srv)
{
- statefulhelper *hlp = srv->parent;
+ helper *hlp = srv->getParent();
- if (srv->rbuf) {
- memFreeBuf(srv->rbuf_sz, srv->rbuf);
- srv->rbuf = NULL;
+ bool needsNewServers = false;
+ hlp->handleKilledServer(srv, needsNewServers);
+ if (needsNewServers) {
+ debugs(80, DBG_IMPORTANT, "Starting new helpers");
+ helperOpenServers(hlp);
}
-#if 0
- srv->wqueue->clean();
-
- delete srv->wqueue;
-
-#endif
-
- /* TODO: walk the local queue of requests and carry them all out */
- if (Comm::IsConnOpen(srv->writePipe))
- srv->closeWritePipeSafely(hlp->id_name);
-
- dlinkDelete(&srv->link, &hlp->servers);
-
- assert(hlp->childs.n_running > 0);
- -- hlp->childs.n_running;
-
- if (!srv->flags.shutdown) {
- assert( hlp->childs.n_active > 0);
- -- hlp->childs.n_active;
- debugs(84, DBG_CRITICAL, "WARNING: " << hlp->id_name << " #" << srv->index << " exited");
+ srv->dropQueued();
- if (hlp->childs.needNew() > 0) {
- debugs(80, DBG_IMPORTANT, "Too few " << hlp->id_name << " processes are running (need " << hlp->childs.needNew() << "/" << hlp->childs.n_max << ")");
-
- if (hlp->childs.n_active < hlp->childs.n_startup && hlp->last_restart > squid_curtime - 30) {
- if (srv->stats.replies < 1)
- fatalf("The %s helpers are crashing too rapidly, need help!\n", hlp->id_name);
- else
- debugs(80, DBG_CRITICAL, "ERROR: The " << hlp->id_name << " helpers are crashing too rapidly, need help!");
- }
-
- debugs(80, DBG_IMPORTANT, "Starting new helpers");
- helperStatefulOpenServers(hlp);
- }
- }
-
- while (!srv->requests.empty()) {
- // XXX: re-schedule these on another helper?
- Helper::Xaction *r = srv->requests.front();
- srv->requests.pop_front();
- void *cbdata;
+ delete srv;
+}
- if (cbdataReferenceValidDone(r->request.data, &cbdata)) {
- r->reply.result = Helper::Unknown;
- r->request.callback(cbdata, r->reply);
- }
+// XXX: Almost duplicates helper_server::HelperServerClosed() because helperOpenServers() is not a virtual method of the `helper` class
+// TODO: Fix the `helper` class hierarchy to use CbdataParent and virtual functions.
+void
+helper_stateful_server::HelperServerClosed(helper_stateful_server *srv)
+{
+ statefulhelper *hlp = static_cast<statefulhelper *>(srv->getParent());
- delete r;
+ bool needsNewServers = false;
+ hlp->handleKilledServer(srv, needsNewServers);
+ if (needsNewServers) {
+ debugs(80, DBG_IMPORTANT, "Starting new helpers");
+ helperStatefulOpenServers(hlp);
}
- if (srv->data != NULL)
- hlp->datapool->freeOne(srv->data);
-
- cbdataReferenceDone(srv->parent);
+ srv->dropQueued();
delete srv;
}
HLPCB *callback = r->request.callback;
r->request.callback = nullptr;
void *cbdata = nullptr;
- cbdataReferenceValidDone(r->request.data, &cbdata);
- callback(cbdata, r->reply);
+ if (cbdataReferenceValidDone(r->request.data, &cbdata))
+ callback(cbdata, r->reply);
}
}
if (r && cbdataReferenceValid(r->request.data)) {
r->reply.finalize();
- r->reply.whichServer = srv;
+ r->reply.reservationId = srv->reservationId;
r->request.callback(r->request.data, r->reply);
} else {
debugs(84, DBG_IMPORTANT, "StatefulHandleRead: no callback data registered");
if (called)
helperStatefulServerDone(srv);
else
- helperStatefulReleaseServer(srv);
+ hlp->cancelReservation(srv->reservationId);
}
if (Comm::IsConnOpen(srv->readPipe) && !fd_table[srv->readPipe->fd].closing()) {
}
static helper_stateful_server *
-StatefulGetFirstAvailable(const statefulhelper * hlp)
+StatefulGetFirstAvailable(statefulhelper * hlp)
{
dlink_node *n;
helper_stateful_server *srv = NULL;
+ helper_stateful_server *oldestReservedServer = nullptr;
debugs(84, 5, "StatefulGetFirstAvailable: Running servers " << hlp->childs.n_running);
if (hlp->childs.n_running == 0)
if (srv->stats.pending)
continue;
- if (srv->flags.reserved)
+ if (srv->reserved()) {
+ if ((squid_curtime - srv->reservationStart) > hlp->childs.reservationTimeout) {
+ if (!oldestReservedServer)
+ oldestReservedServer = srv;
+ else if (oldestReservedServer->reservationStart < srv->reservationStart)
+ oldestReservedServer = srv;
+ debugs(84, 5, "the earlier reserved server is the srv-" << oldestReservedServer->index);
+ }
continue;
+ }
if (srv->flags.shutdown)
continue;
return srv;
}
+ if (oldestReservedServer) {
+ debugs(84, 5, "expired reservation " << oldestReservedServer->reservationId << " for srv-" << oldestReservedServer->index);
+ return oldestReservedServer;
+ }
+
debugs(84, 5, "StatefulGetFirstAvailable: None available.");
- return NULL;
+ return nullptr;
}
static void
if (!cbdataReferenceValid(r->request.data)) {
debugs(84, DBG_IMPORTANT, "helperStatefulDispatch: invalid callback data");
delete r;
- helperStatefulReleaseServer(srv);
+ hlp->cancelReservation(srv->reservationId);
return;
}
debugs(84, 9, "helperStatefulDispatch busying helper " << hlp->id_name << " #" << srv->index);
+ assert(srv->reservationId);
+ r->reply.reservationId = srv->reservationId;
+
if (r->request.placeholder == 1) {
/* a callback is needed before this request can _use_ a helper. */
/* we don't care about releasing this helper. The request NEVER
* gets to the helper. So we throw away the return code */
r->reply.result = Helper::Unknown;
- r->reply.whichServer = srv;
r->request.callback(r->request.data, r->reply);
/* throw away the placeholder */
delete r;
return;
}
- srv->flags.reserved = true;
srv->requests.push_back(r);
srv->dispatch_time = current_time;
AsyncCall::Pointer call = commCbCall(5,5, "helperStatefulDispatchWriteDone",
{
Helper::Xaction *r;
helper_stateful_server *srv;
-
- while ((srv = StatefulGetFirstAvailable(hlp)) && (r = hlp->nextRequest()))
+ while ((srv = StatefulGetFirstAvailable(hlp)) && (r = hlp->nextRequest())) {
+ debugs(84, 5, "found srv-" << srv->index);
+ hlp->reserveServer(srv);
helperStatefulDispatch(srv, r);
+ }
}
static void
{
if (!srv->flags.shutdown) {
helperStatefulKickQueue(srv->parent);
- } else if (!srv->flags.closing && !srv->flags.reserved && !srv->stats.pending) {
+ } else if (!srv->flags.closing && !srv->reserved() && !srv->stats.pending) {
srv->closeWritePipeSafely(srv->parent->id_name);
return;
}
debugs(26, 3, HERE << io.conn);
helper_server *srv = static_cast<helper_server *>(io.data);
- if (!cbdataReferenceValid(srv))
- return;
-
srv->checkForTimedOutRequests(srv->parent->retryTimedOut);
debugs(84, 3, HERE << io.conn << " establish new helper_server::requestTimeout");