diff options
Diffstat (limited to 'src/libstore')
-rw-r--r-- | src/libstore/gc.cc | 84 | ||||
-rw-r--r-- | src/libstore/local-store.cc | 6 | ||||
-rw-r--r-- | src/libstore/local-store.hh | 24 |
3 files changed, 67 insertions, 47 deletions
diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc index 5d91829f1..996f26a95 100644 --- a/src/libstore/gc.cc +++ b/src/libstore/gc.cc @@ -77,60 +77,73 @@ Path LocalFSStore::addPermRoot(const StorePath & storePath, const Path & _gcRoot } -void LocalStore::addTempRoot(const StorePath & path) +void LocalStore::createTempRootsFile() { - auto state(_state.lock()); + auto fdTempRoots(_fdTempRoots.lock()); /* Create the temporary roots file for this process. */ - if (!state->fdTempRoots) { - - while (1) { - if (pathExists(fnTempRoots)) - /* It *must* be stale, since there can be no two - processes with the same pid. */ - unlink(fnTempRoots.c_str()); + if (*fdTempRoots) return; - state->fdTempRoots = openLockFile(fnTempRoots, true); + while (1) { + if (pathExists(fnTempRoots)) + /* It *must* be stale, since there can be no two + processes with the same pid. */ + unlink(fnTempRoots.c_str()); - debug("acquiring write lock on '%s'", fnTempRoots); - lockFile(state->fdTempRoots.get(), ltWrite, true); + *fdTempRoots = openLockFile(fnTempRoots, true); - /* Check whether the garbage collector didn't get in our - way. */ - struct stat st; - if (fstat(state->fdTempRoots.get(), &st) == -1) - throw SysError("statting '%1%'", fnTempRoots); - if (st.st_size == 0) break; + debug("acquiring write lock on '%s'", fnTempRoots); + lockFile(fdTempRoots->get(), ltWrite, true); - /* The garbage collector deleted this file before we could - get a lock. (It won't delete the file after we get a - lock.) Try again. */ - } + /* Check whether the garbage collector didn't get in our + way. */ + struct stat st; + if (fstat(fdTempRoots->get(), &st) == -1) + throw SysError("statting '%1%'", fnTempRoots); + if (st.st_size == 0) break; + /* The garbage collector deleted this file before we could get + a lock. (It won't delete the file after we get a lock.) + Try again. */ } +} + - if (!state->fdGCLock) - state->fdGCLock = openGCLock(); +void LocalStore::addTempRoot(const StorePath & path) +{ + createTempRootsFile(); + + /* Open/create the global GC lock file. */ + { + auto fdGCLock(_fdGCLock.lock()); + if (!*fdGCLock) + *fdGCLock = openGCLock(); + } restart: - FdLock gcLock(state->fdGCLock.get(), ltRead, false, ""); + /* Try to acquire a shared global GC lock (non-blocking). This + only succeeds if the garbage collector is not currently + running. */ + FdLock gcLock(_fdGCLock.lock()->get(), ltRead, false, ""); if (!gcLock.acquired) { /* We couldn't get a shared global GC lock, so the garbage collector is running. So we have to connect to the garbage collector and inform it about our root. */ - if (!state->fdRootsSocket) { + auto fdRootsSocket(_fdRootsSocket.lock()); + + if (!*fdRootsSocket) { auto socketPath = stateDir.get() + gcSocketPath; debug("connecting to '%s'", socketPath); - state->fdRootsSocket = createUnixDomainSocket(); + *fdRootsSocket = createUnixDomainSocket(); try { - nix::connect(state->fdRootsSocket.get(), socketPath); + nix::connect(fdRootsSocket->get(), socketPath); } catch (SysError & e) { /* The garbage collector may have exited, so we need to restart. */ if (e.errNo == ECONNREFUSED) { debug("GC socket connection refused"); - state->fdRootsSocket.close(); + fdRootsSocket->close(); goto restart; } throw; @@ -139,9 +152,9 @@ void LocalStore::addTempRoot(const StorePath & path) try { debug("sending GC root '%s'", printStorePath(path)); - writeFull(state->fdRootsSocket.get(), printStorePath(path) + "\n", false); + writeFull(fdRootsSocket->get(), printStorePath(path) + "\n", false); char c; - readFull(state->fdRootsSocket.get(), &c, 1); + readFull(fdRootsSocket->get(), &c, 1); assert(c == '1'); debug("got ack for GC root '%s'", printStorePath(path)); } catch (SysError & e) { @@ -149,20 +162,21 @@ void LocalStore::addTempRoot(const StorePath & path) restart. */ if (e.errNo == EPIPE || e.errNo == ECONNRESET) { debug("GC socket disconnected"); - state->fdRootsSocket.close(); + fdRootsSocket->close(); goto restart; } throw; } catch (EndOfFile & e) { debug("GC socket disconnected"); - state->fdRootsSocket.close(); + fdRootsSocket->close(); goto restart; } } - /* Append the store path to the temporary roots file. */ + /* Record the store path in the temporary roots file so it will be + seen by a future run of the garbage collector. */ auto s = printStorePath(path) + '\0'; - writeFull(state->fdTempRoots.get(), s); + writeFull(_fdTempRoots.lock()->get(), s); } diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index 3bab10af9..be21e3ca0 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -441,9 +441,9 @@ LocalStore::~LocalStore() } try { - auto state(_state.lock()); - if (state->fdTempRoots) { - state->fdTempRoots = -1; + auto fdTempRoots(_fdTempRoots.lock()); + if (*fdTempRoots) { + *fdTempRoots = -1; unlink(fnTempRoots.c_str()); } } catch (...) { diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh index 4579c2f62..06d36a7d5 100644 --- a/src/libstore/local-store.hh +++ b/src/libstore/local-store.hh @@ -59,15 +59,6 @@ private: struct Stmts; std::unique_ptr<Stmts> stmts; - /* The global GC lock */ - AutoCloseFD fdGCLock; - - /* The file to which we write our temporary roots. */ - AutoCloseFD fdTempRoots; - - /* Connection to the garbage collector. */ - AutoCloseFD fdRootsSocket; - /* The last time we checked whether to do an auto-GC, or an auto-GC finished. */ std::chrono::time_point<std::chrono::steady_clock> lastGCCheck; @@ -156,6 +147,21 @@ public: void addTempRoot(const StorePath & path) override; +private: + + void createTempRootsFile(); + + /* The file to which we write our temporary roots. */ + Sync<AutoCloseFD> _fdTempRoots; + + /* The global GC lock. */ + Sync<AutoCloseFD> _fdGCLock; + + /* Connection to the garbage collector. */ + Sync<AutoCloseFD> _fdRootsSocket; + +public: + void addIndirectRoot(const Path & path) override; private: |