Report cache_peer context in probe and standby pool messages

src/CachePeer.cc

@@ -8,13 +8,15 @@
 
 #include "squid.h"
 #include "acl/Gadgets.h"
+#include "base/PrecomputedCodeContext.h"
 #include "CachePeer.h"
 #include "defines.h"
 #include "neighbors.h"
 #include "NeighborTypeDomainList.h"
 #include "pconn.h"
 #include "PeerDigest.h"
 #include "PeerPoolMgr.h"
+#include "sbuf/Stream.h"
 #include "SquidConfig.h"
 #include "util.h"
 
@@ -23,7 +25,8 @@ CBDATA_CLASS_INIT(CachePeer);
 CachePeer::CachePeer(const char * const hostname):
     name(xstrdup(hostname)),
     host(xstrdup(hostname)),
-    tlsContext(secure, sslContext)
+    tlsContext(secure, sslContext),
+    probeCodeContext(new PrecomputedCodeContext("cache_peer probe", ToSBuf("current cache_peer probe: ", *this)))
 {
     Tolower(host); // but .name preserves original spelling
 }

src/CachePeer.h

@@ -11,6 +11,7 @@
 
 #include "acl/forward.h"
 #include "base/CbcPointer.h"
+#include "base/forward.h"
 #include "enums.h"
 #include "http/StatusCode.h"
 #include "icp_opcode.h"
@@ -224,6 +225,8 @@ class CachePeer
     int front_end_https = 0; ///< 0 - off, 1 - on, 2 - auto
     int connection_auth = 2; ///< 0 - off, 1 - on, 2 - auto
 
+    PrecomputedCodeContextPointer probeCodeContext;
+
 private:
     void countFailure();
 };

src/PeerPoolMgr.cc

@@ -9,6 +9,7 @@
 #include "squid.h"
 #include "AccessLogEntry.h"
 #include "base/AsyncCallbacks.h"
+#include "base/PrecomputedCodeContext.h"
 #include "base/RunnersRegistry.h"
 #include "CachePeer.h"
 #include "CachePeers.h"
@@ -23,18 +24,27 @@
 #include "neighbors.h"
 #include "pconn.h"
 #include "PeerPoolMgr.h"
+#include "sbuf/Stream.h"
 #include "security/BlindPeerConnector.h"
 #include "SquidConfig.h"
 
 CBDATA_CLASS_INIT(PeerPoolMgr);
 
 PeerPoolMgr::PeerPoolMgr(CachePeer *aPeer): AsyncJob("PeerPoolMgr"),
     peer(cbdataReference(aPeer)),
-    request(),
     transportWait(),
     encryptionWait(),
     addrUsed(0)
 {
+    const auto mx = MasterXaction::MakePortless<XactionInitiator::initPeerPool>();
+
+    codeContext = new PrecomputedCodeContext("cache_peer standby pool", ToSBuf("current cache_peer standby pool: ", *peer,
+            Debug::Extra, "current master transaction: ", mx->id));
+
+    // ErrorState, getOutgoingAddress(), and other APIs may require a request.
+    // We fake one. TODO: Optionally send this request to peers?
+    request = new HttpRequest(Http::METHOD_OPTIONS, AnyP::PROTO_HTTP, "http", "*", mx);
+    request->url.host(peer->host);
 }
 
 PeerPoolMgr::~PeerPoolMgr()
@@ -46,13 +56,6 @@ void
 PeerPoolMgr::start()
 {
     AsyncJob::start();
-
-    const auto mx = MasterXaction::MakePortless<XactionInitiator::initPeerPool>();
-    // ErrorState, getOutgoingAddress(), and other APIs may require a request.
-    // We fake one. TODO: Optionally send this request to peers?
-    request = new HttpRequest(Http::METHOD_OPTIONS, AnyP::PROTO_HTTP, "http", "*", mx);
-    request->url.host(peer->host);
-
     checkpoint("peer initialized");
 }
 
@@ -228,7 +231,14 @@ PeerPoolMgr::checkpoint(const char *reason)
 void
 PeerPoolMgr::Checkpoint(const Pointer &mgr, const char *reason)
 {
-    CallJobHere1(48, 5, mgr, PeerPoolMgr, checkpoint, reason);
+    if (!mgr.valid()) {
+        debugs(48, 5, reason << " but no mgr");
+        return;
+    }
+
+    CallService(mgr->codeContext, [&] {
+        CallJobHere1(48, 5, mgr, PeerPoolMgr, checkpoint, reason);
+    });
 }
 
 /// launches PeerPoolMgrs for peers configured with standby.limit
@@ -254,7 +264,9 @@ PeerPoolMgrsRr::syncConfig()
         if (p->standby.limit) {
             p->standby.mgr = new PeerPoolMgr(p);
             p->standby.pool = new PconnPool(p->name, p->standby.mgr);
-            AsyncJob::Start(p->standby.mgr.get());
+            CallService(p->standby.mgr->codeContext, [&] {
+                AsyncJob::Start(p->standby.mgr.get());
+            });
         }
     }
 }

src/PeerPoolMgr.h

@@ -10,6 +10,7 @@
 #define SQUID_SRC_PEERPOOLMGR_H
 
 #include "base/AsyncJob.h"
+#include "base/forward.h"
 #include "base/JobWait.h"
 #include "comm/forward.h"
 #include "security/forward.h"
@@ -32,6 +33,8 @@ class PeerPoolMgr: public AsyncJob
     explicit PeerPoolMgr(CachePeer *aPeer);
     ~PeerPoolMgr() override;
 
+    PrecomputedCodeContextPointer codeContext;
+
 protected:
     /* AsyncJob API */
     void start() override;

src/base/Makefile.am

@@ -51,6 +51,7 @@ libbase_la_SOURCES = \
 	OnOff.h \
 	Packable.h \
 	PackableStream.h \
+	PrecomputedCodeContext.h \
 	Random.cc \
 	Random.h \
 	RandomUuid.cc \

src/base/PrecomputedCodeContext.h

@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 1996-2024 The Squid Software Foundation and contributors
+ *
+ * Squid software is distributed under GPLv2+ license and includes
+ * contributions from numerous individuals and organizations.
+ * Please see the COPYING and CONTRIBUTORS files for details.
+ */
+
+#ifndef SQUID_SRC_BASE_PRECOMPUTEDCODECONTEXT_H
+#define SQUID_SRC_BASE_PRECOMPUTEDCODECONTEXT_H
+
+#include "base/CodeContext.h"
+#include "base/InstanceId.h"
+#include "sbuf/SBuf.h"
+
+#include <ostream>
+
+/// CodeContext with constant details known at construction time
+class PrecomputedCodeContext: public CodeContext
+{
+public:
+    typedef RefCount<PrecomputedCodeContext> Pointer;
+
+    PrecomputedCodeContext(const char *gist, const SBuf &detail): gist_(gist), detail_(detail)
+    {}
+
+    /* CodeContext API */
+    ScopedId codeContextGist() const override { return ScopedId(gist_); }
+    std::ostream &detailCodeContext(std::ostream &os) const override { return os << Debug::Extra << detail_; }
+
+private:
+    const char *gist_; ///< the id used in codeContextGist()
+    const SBuf detail_; ///< the detail used in detailCodeContext()
+};
+
+#endif /* SQUID_SRC_BASE_PRECOMPUTEDCODECONTEXT_H */
+

src/base/forward.h

@@ -15,6 +15,7 @@ class AsyncJob;
 class CallDialer;
 class CodeContext;
 class DelayedAsyncCalls;
+class PrecomputedCodeContext;
 class Raw;
 class RegexPattern;
 class ScopedId;
@@ -28,6 +29,7 @@ template<class Answer> class AsyncCallback;
 typedef CbcPointer<AsyncJob> AsyncJobPointer;
 typedef RefCount<CodeContext> CodeContextPointer;
 using AsyncCallPointer = RefCount<AsyncCall>;
+using PrecomputedCodeContextPointer = RefCount<PrecomputedCodeContext>;
 
 #endif /* SQUID_SRC_BASE_FORWARD_H */
 

src/neighbors.cc

@@ -14,6 +14,7 @@
 #include "base/EnumIterator.h"
 #include "base/IoManip.h"
 #include "base/PackableStream.h"
+#include "base/PrecomputedCodeContext.h"
 #include "CacheDigest.h"
 #include "CachePeer.h"
 #include "CachePeers.h"
@@ -570,9 +571,12 @@ neighborsUdpPing(HttpRequest * request,
 
     reqnum = icpSetCacheKey((const cache_key *)entry->key);
 
+    const auto savedContext = CodeContext::Current();
     for (size_t i = 0; i < Config.peers->size(); ++i) {
         const auto p = &Config.peers->nextPeerToPing(i);
 
+        CodeContext::Reset(p->probeCodeContext);
+
         debugs(15, 5, "candidate: " << *p);
 
         if (!peerWouldBePinged(p, ps))
@@ -661,6 +665,7 @@ neighborsUdpPing(HttpRequest * request,
         if ((p->type != PEER_MULTICAST) && (p->stats.probe_start == 0))
             p->stats.probe_start = squid_curtime;
     }
+    CodeContext::Reset(savedContext);
 
     /*
      * How many replies to expect?
@@ -1054,8 +1059,7 @@ int
 neighborUp(const CachePeer * p)
 {
     if (!p->tcp_up) {
-        // TODO: When CachePeer gets its own CodeContext, pass that context instead of nullptr
-        CallService(nullptr, [&] {
+        CallService(p->probeCodeContext, [&] {
             peerProbeConnect(const_cast<CachePeer*>(p));
         });
         return 0;
@@ -1171,8 +1175,12 @@ peerDnsRefreshCheck(void *)
 static void
 peerDnsRefreshStart()
 {
-    for (const auto &p: CurrentCachePeers())
+    const auto savedContext = CodeContext::Current();
+    for (const auto &p: CurrentCachePeers()) {
+        CodeContext::Reset(p->probeCodeContext);
         ipcache_nbgethostbyname(p->host, peerDNSConfigure, p.get());
+    }
+    CodeContext::Reset(savedContext);
 
     peerScheduleDnsRefreshCheck(3600.0);
 }