* True parallel builds. Nix can now run as many build jobs in

parallel as possible (similar to GNU Make's `-j' switch).  This is
  useful on SMP systems, but it is especially useful for doing builds
  on multiple machines.  The idea is that a large derivation is
  initiated on one master machine, which then distributes
  sub-derivations to any number of slave machines.  This should not
  happen synchronously or in lock-step, so the master must be capable
  of dealing with multiple parallel build jobs.  We now have the
  infrastructure to support this.

  TODO: substitutes are currently broken.
This commit is contained in:
Eelco Dolstra 2004-05-11 18:05:44 +00:00
parent aea436503e
commit c8d3882cdc
12 changed files with 696 additions and 309 deletions

View file

@ -15,9 +15,15 @@ extern "C" {
#include "config.h" #include "config.h"
volatile sig_atomic_t blockInt = 0;
void sigintHandler(int signo) void sigintHandler(int signo)
{ {
_isInterrupted = 1; if (!blockInt) {
_isInterrupted = 1;
blockInt = 1;
}
} }
@ -150,7 +156,17 @@ int main(int argc, char * * argv)
#endif #endif
try { try {
initAndRun(argc, argv); try {
initAndRun(argc, argv);
} catch (...) {
/* Subtle: we have to make sure that any `interrupted'
condition is discharged before we reach printMsg()
below, since otherwise it will throw an (uncaught)
exception. */
blockInt = 1; /* ignore further SIGINTs */
_isInterrupted = 0;
throw;
}
} catch (UsageError & e) { } catch (UsageError & e) {
printMsg(lvlError, printMsg(lvlError,
format( format(

View file

@ -2,7 +2,7 @@ noinst_LIBRARIES = libstore.a
libstore_a_SOURCES = \ libstore_a_SOURCES = \
store.cc store.hh storeexpr.cc storeexpr.hh \ store.cc store.hh storeexpr.cc storeexpr.hh \
normalise.cc normalise.hh exec.cc exec.hh \ normalise.cc normalise.hh \
globals.cc globals.hh db.cc db.hh \ globals.cc globals.hh db.cc db.hh \
references.cc references.hh pathlocks.cc pathlocks.hh references.cc references.hh pathlocks.cc pathlocks.hh

View file

@ -1,140 +0,0 @@
#include <iostream>
#include <cstdio>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <unistd.h>
#include <fcntl.h>
#include "exec.hh"
#include "util.hh"
#include "globals.hh"
static string pathNullDevice = "/dev/null";
/* Run a program. */
void runProgram(const string & program,
const Strings & args, Environment env,
const string & logFileName)
{
/* Create a log file. */
string logCommand =
verbosity >= buildVerbosity
? "tee " + logFileName + " >&2"
: "cat > " + logFileName;
/* !!! auto-pclose on exit */
FILE * logFile = popen(logCommand.c_str(), "w"); /* !!! escaping */
if (!logFile)
throw SysError(format("creating log file `%1%'") % logFileName);
/* Create a temporary directory where the build will take
place. */
Path tmpDir = createTempDir();
AutoDelete delTmpDir(tmpDir);
/* For convenience, set an environment pointing to the top build
directory. */
env["NIX_BUILD_TOP"] = tmpDir;
/* Also set TMPDIR and variants to point to this directory. */
env["TMPDIR"] = tmpDir;
env["TEMPDIR"] = tmpDir;
env["TMP"] = tmpDir;
env["TEMP"] = tmpDir;
/* Fork a child to build the package. */
pid_t pid;
switch (pid = fork()) {
case -1:
throw SysError("unable to fork");
case 0:
try { /* child */
if (chdir(tmpDir.c_str()) == -1)
throw SysError(format("changing into to `%1%'") % tmpDir);
/* Fill in the arguments. */
const char * argArr[args.size() + 2];
const char * * p = argArr;
string progName = baseNameOf(program);
*p++ = progName.c_str();
for (Strings::const_iterator i = args.begin();
i != args.end(); i++)
*p++ = i->c_str();
*p = 0;
/* Fill in the environment. */
Strings envStrs;
const char * envArr[env.size() + 1];
p = envArr;
for (Environment::const_iterator i = env.begin();
i != env.end(); i++)
*p++ = envStrs.insert(envStrs.end(),
i->first + "=" + i->second)->c_str();
*p = 0;
/* Dup the log handle into stderr. */
if (dup2(fileno(logFile), STDERR_FILENO) == -1)
throw SysError("cannot pipe standard error into log file");
/* Dup stderr to stdin. */
if (dup2(STDERR_FILENO, STDOUT_FILENO) == -1)
throw SysError("cannot dup stderr into stdout");
/* Reroute stdin to /dev/null. */
int fdDevNull = open(pathNullDevice.c_str(), O_RDWR);
if (fdDevNull == -1)
throw SysError(format("cannot open `%1%'") % pathNullDevice);
if (dup2(fdDevNull, STDIN_FILENO) == -1)
throw SysError("cannot dup null device into stdin");
/* Execute the program. This should not return. */
execve(program.c_str(), (char * *) argArr, (char * *) envArr);
throw SysError(format("unable to execute %1%") % program);
} catch (exception & e) {
cerr << format("build error: %1%\n") % e.what();
}
_exit(1);
}
/* parent */
/* Close the logging pipe. Note that this should not cause
the logger to exit until builder exits (because the latter
has an open file handle to the former). */
pclose(logFile);
/* Wait for the child to finish. */
int status;
if (waitpid(pid, &status, 0) != pid)
throw Error("unable to wait for child");
checkInterrupt();
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
if (keepFailed) {
printMsg(lvlTalkative,
format("program `%1%' failed; keeping build directory `%2%'")
% program % tmpDir);
delTmpDir.cancel();
}
if (WIFEXITED(status))
throw Error(format("program `%1%' failed with exit code %2%")
% program % WEXITSTATUS(status));
else if (WIFSIGNALED(status))
throw Error(format("program `%1%' failed due to signal %2%")
% program % WTERMSIG(status));
else
throw Error(format("program `%1%' died abnormally") % program);
}
}

View file

@ -1,22 +0,0 @@
#ifndef __EXEC_H
#define __EXEC_H
#include <string>
#include <map>
#include "util.hh"
using namespace std;
/* A Unix environment is a mapping from strings to strings. */
typedef map<string, string> Environment;
/* Run a program. */
void runProgram(const string & program,
const Strings & args, Environment env,
const string & logFileName);
#endif /* !__EXEC_H */

View file

@ -1,12 +1,190 @@
#include <map> #include <map>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <fcntl.h>
#include <signal.h>
#include <unistd.h>
#include "normalise.hh" #include "normalise.hh"
#include "references.hh" #include "references.hh"
#include "exec.hh"
#include "pathlocks.hh" #include "pathlocks.hh"
#include "globals.hh" #include "globals.hh"
static string pathNullDevice = "/dev/null";
/* A goal is a store expression that still has to be normalised. */
struct Goal
{
/* The path of the store expression. */
Path nePath;
/* The store expression stored at nePath. */
StoreExpr expr;
/* The unfinished inputs are the input store expressions that
still have to be normalised. */
PathSet unfinishedInputs;
/* The waiters are the store expressions that have this one as an
unfinished input. */
PathSet waiters;
/* The remainder is state held during the build. */
/* Locks on the output paths. */
PathLocks outputLocks;
/* Input paths, with their closure elements. */
ClosureElems inClosures;
/* Referenceable paths (i.e., input and output paths). */
PathSet allPaths;
/* The process ID of the builder. */
pid_t pid;
/* The temporary directory. */
Path tmpDir;
/* File descriptor for the log file. */
int fdLogFile;
/* Pipe for the builder's standard output/error. */
int fdsLogger[2];
Goal();
~Goal();
void deleteTmpDir(bool force);
};
Goal::Goal()
: pid(0)
, tmpDir("")
, fdLogFile(0)
{
fdsLogger[0] = 0;
fdsLogger[1] = 0;
}
Goal::~Goal()
{
/* Careful: we should never ever throw an exception from a
destructor. */
if (pid) {
printMsg(lvlError, format("killing child process %1% (%2%)")
% pid % nePath);
/* Send a KILL signal to every process in the child
process group (which hopefully includes *all* its
children). */
if (kill(-pid, SIGKILL) != 0)
printMsg(lvlError, format("killing process %1%") % pid);
else {
/* Wait until the child dies, disregarding the exit
status. */
int status;
while (waitpid(pid, &status, 0) == -1)
if (errno != EINTR) printMsg(lvlError,
format("waiting for process %1%") % pid);
}
}
if (fdLogFile && (close(fdLogFile) != 0))
printMsg(lvlError, format("cannot close fd"));
if (fdsLogger[0] && close(fdsLogger[0]) != 0)
printMsg(lvlError, format("cannot close fd"));
if (fdsLogger[1] && close(fdsLogger[1]) != 0)
printMsg(lvlError, format("cannot close fd"));
try {
deleteTmpDir(false);
} catch (Error & e) {
printMsg(lvlError, format("error (ignored): %1%") % e.msg());
}
}
void Goal::deleteTmpDir(bool force)
{
if (tmpDir != "") {
if (keepFailed && !force)
printMsg(lvlTalkative,
format("builder for `%1%' failed; keeping build directory `%2%'")
% nePath % tmpDir);
else
deletePath(tmpDir);
tmpDir = "";
}
}
/* A set of goals keyed on the path of the store expression. */
typedef map<Path, Goal> Goals;
/* A mapping used to remember for each child process what derivation
store expression it is building. */
typedef map<pid_t, Path> Building;
/* The normaliser class. */
class Normaliser
{
private:
/* The goals of the normaliser. This describes a dependency graph
of derivation expressions that have yet to be normalised. */
Goals goals;
/* The set of `buildable' goals, which are the ones with an empty
list of unfinished inputs. */
PathSet buildable;
/* Child processes currently running. */
Building building;
public:
Normaliser();
/* Add the normalisation of a store expression of a goal. Returns
true if the expression has been added; false if it's
unnecessary (the expression is a closure, or already has a
known successor). */
bool addGoal(Path nePath);
/* Perform build actions until all goals have been realised. */
void run();
private:
/* Start building a derivation. Returns false if we decline to
build it right now. */
bool startBuild(Path nePath);
void startBuildChild(Goal & goal);
/* Read from the logger pipes, and watch for child termination as
a side effect. */
void wait();
/* Wait for child processes to finish building a derivation. */
void reapChild(Goal & goal);
/* Called when a build has finished succesfully. */
void finishGoal(Goal & goal);
/* Removes a goal from the graph and wakes up all waiters. */
void removeGoal(Goal & goal);
};
static Path useSuccessor(const Path & path) static Path useSuccessor(const Path & path)
{ {
string pathSucc; string pathSucc;
@ -18,99 +196,201 @@ static Path useSuccessor(const Path & path)
} }
Path normaliseStoreExpr(const Path & _nePath, PathSet pending) Normaliser::Normaliser()
{ {
startNest(nest, lvlTalkative, }
format("normalising store expression in `%1%'") % (string) _nePath);
/* Try to substitute the expression by any known successors in
order to speed up the rewrite process. */ bool Normaliser::addGoal(Path nePath)
Path nePath = useSuccessor(_nePath); {
checkInterrupt();
Goal goal;
goal.nePath = nePath;
/* If this already a goal, return. */
if (goals.find(nePath) != goals.end()) return true;
/* If we already have a successor, then we are done already; don't
add the expression as a goal. */
Path nfPath;
if (querySuccessor(nePath, nfPath)) return false;
/* Get the store expression. */ /* Get the store expression. */
StoreExpr ne = storeExprFromPath(nePath, pending); goal.expr = storeExprFromPath(nePath);
/* If this is a normal form (i.e., a closure) we are done. */ /* If this is a normal form (i.e., a closure) we are also done. */
if (ne.type == StoreExpr::neClosure) return nePath; if (goal.expr.type == StoreExpr::neClosure) return false;
if (ne.type != StoreExpr::neDerivation) abort(); if (goal.expr.type != StoreExpr::neDerivation) abort();
/* Otherwise, it's a derivation expression for which the successor
is not known, and we have to build it to determine its normal
form. So add it as a goal. */
startNest(nest, lvlChatty,
format("adding build goal `%1%'") % nePath);
/* Inputs may also need to be added as goals if they haven't been
normalised yet. */
for (PathSet::iterator i = goal.expr.derivation.inputs.begin();
i != goal.expr.derivation.inputs.end(); ++i)
if (addGoal(*i)) {
goal.unfinishedInputs.insert(*i);
goals[*i].waiters.insert(nePath);
}
/* Maintain the invariant that all goals with no unfinished inputs
are in the `buildable' set. */
if (goal.unfinishedInputs.empty())
buildable.insert(nePath);
/* Add the goal to the goal graph. */
goals[nePath] = goal;
return true;
}
void Normaliser::run()
{
startNest(nest, lvlChatty, format("running normaliser"));
while (!goals.empty()) {
printMsg(lvlVomit, "loop");
/* Start building as many buildable goals as possible. */
bool madeProgress = false;
for (PathSet::iterator i = buildable.begin();
i != buildable.end(); ++i)
if (startBuild(*i)) {
madeProgress = true;
buildable.erase(*i);
}
if (building.empty())
assert(madeProgress); /* shouldn't happen */
else
wait();
}
assert(buildable.empty() && building.empty());
}
bool Normaliser::startBuild(Path nePath)
{
checkInterrupt();
Goals::iterator goalIt = goals.find(nePath);
assert(goalIt != goals.end());
Goal & goal(goalIt->second);
assert(goal.unfinishedInputs.empty());
startNest(nest, lvlTalkative,
format("starting normalisation of goal `%1%'") % nePath);
/* Otherwise, it's a derivation expression, and we have to build it to
determine its normal form. */
/* Some variables. */
/* Input paths, with their closure elements. */
ClosureElems inClosures;
/* Referenceable paths (i.e., input and output paths). */
PathSet allPaths;
/* The environment to be passed to the builder. */
Environment env;
/* The result. */
StoreExpr nf;
nf.type = StoreExpr::neClosure;
/* The outputs are referenceable paths. */ /* The outputs are referenceable paths. */
for (PathSet::iterator i = ne.derivation.outputs.begin(); for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != ne.derivation.outputs.end(); i++) i != goal.expr.derivation.outputs.end(); ++i)
{ {
debug(format("building path `%1%'") % *i); debug(format("building path `%1%'") % *i);
allPaths.insert(*i); goal.allPaths.insert(*i);
} }
/* Obtain locks on all output paths. The locks are automatically /* Obtain locks on all output paths. The locks are automatically
released when we exit this function or Nix crashes. */ released when we exit this function or Nix crashes. */
PathLocks outputLocks(ne.derivation.outputs); goal.outputLocks.lockPaths(goal.expr.derivation.outputs);
/* Now check again whether there is a successor. This is because /* Now check again whether there is a successor. This is because
another process may have started building in parallel. After another process may have started building in parallel. After
it has finished and released the locks, we can (and should) it has finished and released the locks, we can (and should)
reuse its results. (Strictly speaking the first successor reuse its results. (Strictly speaking the first successor
check above can be omitted, but that would be less efficient.) check can be omitted, but that would be less efficient.) Note
Note that since we now hold the locks on the output paths, no that since we now hold the locks on the output paths, no other
other process can build this expression, so no further checks process can build this expression, so no further checks are
are necessary. */ necessary. */
{ Path nfPath;
Path nePath2 = useSuccessor(nePath); if (querySuccessor(nePath, nfPath)) {
if (nePath != nePath2) { debug(format("skipping build of expression `%1%', someone beat us to it")
StoreExpr ne = storeExprFromPath(nePath2, pending); % nePath);
debug(format("skipping build of expression `%1%', someone beat us to it") goal.outputLocks.setDeletion(true);
% (string) nePath); removeGoal(goal);
if (ne.type != StoreExpr::neClosure) abort(); return true;
outputLocks.setDeletion(true);
return nePath2;
}
} }
/* Right platform? */ /* Right platform? */
if (ne.derivation.platform != thisSystem) if (goal.expr.derivation.platform != thisSystem)
throw Error(format("a `%1%' is required, but I am a `%2%'") throw Error(format("a `%1%' is required, but I am a `%2%'")
% ne.derivation.platform % thisSystem); % goal.expr.derivation.platform % thisSystem);
/* Realise inputs (and remember all input paths). */ /* Realise inputs (and remember all input paths). */
for (PathSet::iterator i = ne.derivation.inputs.begin(); for (PathSet::iterator i = goal.expr.derivation.inputs.begin();
i != ne.derivation.inputs.end(); i++) i != goal.expr.derivation.inputs.end(); ++i)
{ {
checkInterrupt(); checkInterrupt();
Path nfPath = normaliseStoreExpr(*i, pending); Path nfPath = useSuccessor(*i);
realiseClosure(nfPath, pending); realiseClosure(nfPath);
/* !!! nfPath should be a root of the garbage collector while /* !!! nfPath should be a root of the garbage collector while
we are building */ we are building */
StoreExpr ne = storeExprFromPath(nfPath, pending); StoreExpr ne = storeExprFromPath(nfPath);
if (ne.type != StoreExpr::neClosure) abort(); if (ne.type != StoreExpr::neClosure) abort();
for (ClosureElems::iterator j = ne.closure.elems.begin(); for (ClosureElems::iterator j = ne.closure.elems.begin();
j != ne.closure.elems.end(); j++) j != ne.closure.elems.end(); ++j)
{ {
inClosures[j->first] = j->second; goal.inClosures[j->first] = j->second;
allPaths.insert(j->first); goal.allPaths.insert(j->first);
} }
} }
/* We can skip running the builder if all output paths are already
valid. */
bool fastBuild = true;
for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != goal.expr.derivation.outputs.end(); ++i)
{
if (!isValidPath(*i)) {
fastBuild = false;
break;
}
}
if (fastBuild) {
printMsg(lvlChatty, format("skipping build; output paths already exist"));
finishGoal(goal);
return true;
}
/* Otherwise, start the build in a child process. */
startBuildChild(goal);
return true;
}
void Normaliser::startBuildChild(Goal & goal)
{
/* If any of the outputs already exist but are not registered,
delete them. */
for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != goal.expr.derivation.outputs.end(); ++i)
{
Path path = *i;
if (isValidPath(path))
throw Error(format("obstructed build: path `%1%' exists") % path);
if (pathExists(path)) {
debug(format("removing unregistered path `%1%'") % path);
deletePath(path);
}
}
/* Construct the environment passed to the builder. */
typedef map<string, string> Environment;
Environment env;
/* Most shells initialise PATH to some default (/bin:/usr/bin:...) when /* Most shells initialise PATH to some default (/bin:/usr/bin:...) when
PATH is not set. We don't want this, so we fill it in with some dummy PATH is not set. We don't want this, so we fill it in with some dummy
value. */ value. */
@ -130,58 +410,253 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
in the store or in the build directory). */ in the store or in the build directory). */
env["NIX_STORE"] = nixStore; env["NIX_STORE"] = nixStore;
/* Build the environment. */ /* Add all bindings specified in the derivation expression. */
for (StringPairs::iterator i = ne.derivation.env.begin(); for (StringPairs::iterator i = goal.expr.derivation.env.begin();
i != ne.derivation.env.end(); i++) i != goal.expr.derivation.env.end(); ++i)
env[i->first] = i->second; env[i->first] = i->second;
/* We can skip running the builder if all output paths are already /* Create a temporary directory where the build will take
valid. */ place. */
bool fastBuild = true; goal.tmpDir = createTempDir();
for (PathSet::iterator i = ne.derivation.outputs.begin();
i != ne.derivation.outputs.end(); i++) /* For convenience, set an environment pointing to the top build
{ directory. */
if (!isValidPath(*i)) { env["NIX_BUILD_TOP"] = goal.tmpDir;
fastBuild = false;
break; /* Also set TMPDIR and variants to point to this directory. */
env["TMPDIR"] = env["TEMPDIR"] = env["TMP"] = env["TEMP"] = goal.tmpDir;
/* Run the builder. */
printMsg(lvlChatty, format("executing builder `%1%'") %
goal.expr.derivation.builder);
/* Create a log file. */
Path logFileName = nixLogDir + "/" + baseNameOf(goal.nePath);
int fdLogFile = open(logFileName.c_str(),
O_CREAT | O_WRONLY | O_TRUNC, 0666);
if (fdLogFile == -1)
throw SysError(format("creating log file `%1%'") % logFileName);
goal.fdLogFile = fdLogFile;
/* Create a pipe to get the output of the child. */
if (pipe(goal.fdsLogger) != 0)
throw SysError("creating logger pipe");
/* Fork a child to build the package. Note that while we
currently use forks to run and wait for the children, it
shouldn't be hard to use threads for this on systems where
fork() is unavailable or inefficient. */
switch (goal.pid = fork()) {
case -1:
throw SysError("unable to fork");
case 0:
/* Warning: in the child we should absolutely not make any
Berkeley DB calls! */
try { /* child */
/* Put the child in a separate process group so that it
doesn't receive terminal signals. */
if (setpgrp() == -1)
throw SysError(format("setting process group"));
if (chdir(goal.tmpDir.c_str()) == -1)
throw SysError(format("changing into to `%1%'") % goal.tmpDir);
/* Fill in the arguments. */
Strings & args(goal.expr.derivation.args);
const char * argArr[args.size() + 2];
const char * * p = argArr;
string progName = baseNameOf(goal.expr.derivation.builder);
*p++ = progName.c_str();
for (Strings::const_iterator i = args.begin();
i != args.end(); i++)
*p++ = i->c_str();
*p = 0;
/* Fill in the environment. */
Strings envStrs;
const char * envArr[env.size() + 1];
p = envArr;
for (Environment::const_iterator i = env.begin();
i != env.end(); i++)
*p++ = envStrs.insert(envStrs.end(),
i->first + "=" + i->second)->c_str();
*p = 0;
/* Dup the write side of the logger pipe into stderr. */
if (dup2(goal.fdsLogger[1], STDERR_FILENO) == -1)
throw SysError("cannot pipe standard error into log file");
if (close(goal.fdsLogger[0]) != 0) /* close read side */
throw SysError("closing fd");
/* Dup stderr to stdin. */
if (dup2(STDERR_FILENO, STDOUT_FILENO) == -1)
throw SysError("cannot dup stderr into stdout");
/* Reroute stdin to /dev/null. */
int fdDevNull = open(pathNullDevice.c_str(), O_RDWR);
if (fdDevNull == -1)
throw SysError(format("cannot open `%1%'") % pathNullDevice);
if (dup2(fdDevNull, STDIN_FILENO) == -1)
throw SysError("cannot dup null device into stdin");
/* Close all other file descriptors. */
int maxFD = 0;
maxFD = sysconf(_SC_OPEN_MAX);
debug(format("closing fds up to %1%") % (int) maxFD);
for (int fd = 0; fd < maxFD; ++fd)
if (fd != STDIN_FILENO && fd != STDOUT_FILENO && fd != STDERR_FILENO)
close(fd); /* ignore result */
/* Execute the program. This should not return. */
execve(goal.expr.derivation.builder.c_str(),
(char * *) argArr, (char * *) envArr);
throw SysError(format("unable to execute %1%")
% goal.expr.derivation.builder);
} catch (exception & e) {
cerr << format("build error: %1%\n") % e.what();
} }
_exit(1);
} }
if (!fastBuild) { /* parent */
/* If any of the outputs already exist but are not registered, building[goal.pid] = goal.nePath;
delete them. */
for (PathSet::iterator i = ne.derivation.outputs.begin(); /* Close the write side of the logger pipe. */
i != ne.derivation.outputs.end(); i++) if (close(goal.fdsLogger[1]) != 0)
{ throw SysError("closing fd");
Path path = *i; goal.fdsLogger[1] = 0;
if (isValidPath(path)) }
throw Error(format("obstructed build: path `%1%' exists") % path);
if (pathExists(path)) {
debug(format("removing unregistered path `%1%'") % path); void Normaliser::wait()
deletePath(path); {
checkInterrupt();
/* Process log output from the children. We also use this to
detect child termination: if we get EOF on the logger pipe of a
build, we assume that the builder has terminated. */
/* Use select() to wait for the input side of any logger pipe to
become `available'. Note that `available' (i.e., non-blocking)
includes EOF. */
fd_set fds;
FD_ZERO(&fds);
int fdMax = 0;
for (Building::iterator i = building.begin();
i != building.end(); ++i)
{
Goal & goal(goals[i->second]);
int fd = goal.fdsLogger[0];
FD_SET(fd, &fds);
if (fd >= fdMax) fdMax = fd + 1;
}
if (select(fdMax, &fds, 0, 0, 0) == -1) {
if (errno == EINTR) return;
throw SysError("waiting for input");
}
/* Process all available file descriptors. */
for (Building::iterator i = building.begin();
i != building.end(); ++i)
{
checkInterrupt();
Goal & goal(goals[i->second]);
int fd = goal.fdsLogger[0];
if (FD_ISSET(fd, &fds)) {
unsigned char buffer[1024];
ssize_t rd = read(fd, buffer, sizeof(buffer));
if (rd == -1) {
if (errno != EINTR)
throw SysError(format("reading from `%1%'")
% goal.nePath);
} else if (rd == 0) {
debug(format("EOF on `%1%'") % goal.nePath);
reapChild(goal);
} else {
printMsg(lvlVomit, format("read %1% bytes from `%2%'")
% rd % goal.nePath);
writeFull(goal.fdLogFile, buffer, rd);
if (verbosity >= buildVerbosity)
writeFull(STDERR_FILENO, buffer, rd);
} }
} }
}
}
/* Run the builder. */
startNest(nest2, lvlChatty, void Normaliser::reapChild(Goal & goal)
format("executing builder `%1%'") % ne.derivation.builder); {
runProgram(ne.derivation.builder, ne.derivation.args, env, int status;
nixLogDir + "/" + baseNameOf(nePath));
printMsg(lvlChatty, format("builder completed")); /* Since we got an EOF on the logger pipe, the builder is presumed
nest2.close(); to have terminated. In fact, the builder could also have
simply have closed its end of the pipe --- just don't do that
:-) */
if (waitpid(goal.pid, &status, WNOHANG) != goal.pid)
throw SysError(format("builder for `%1%' should have terminated")
% goal.nePath);
/* So the child is gone now. */
pid_t pid = goal.pid;
goal.pid = 0;
/* Close the read side of the logger pipe. */
if (close(goal.fdsLogger[0]) != 0)
throw SysError("closing fd");
goal.fdsLogger[0] = 0;
/* Close the log file. */
if (close(goal.fdLogFile) != 0)
throw SysError("closing fd");
goal.fdLogFile = 0;
debug(format("builder process %1% finished") % pid);
/* Check the exit status. */
if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
goal.deleteTmpDir(false);
if (WIFEXITED(status))
throw Error(format("builder for `%1%' failed with exit code %2%")
% goal.nePath % WEXITSTATUS(status));
else if (WIFSIGNALED(status))
throw Error(format("builder for `%1%' failed due to signal %2%")
% goal.nePath % WTERMSIG(status));
else
throw Error(format("builder for `%1%' failed died abnormally") % goal.nePath);
} else } else
printMsg(lvlChatty, format("fast build succesful")); goal.deleteTmpDir(true);
startNest(nest3, lvlChatty, format("determining closure value")); finishGoal(goal);
building.erase(pid);
}
void Normaliser::finishGoal(Goal & goal)
{
/* The resulting closure expression. */
StoreExpr nf;
nf.type = StoreExpr::neClosure;
startNest(nest, lvlTalkative,
format("finishing normalisation of goal `%1%'") % goal.nePath);
/* Check whether the output paths were created, and grep each /* Check whether the output paths were created, and grep each
output path to determine what other paths it references. Also make all output path to determine what other paths it references. Also make all
output paths read-only. */ output paths read-only. */
PathSet usedPaths; PathSet usedPaths;
for (PathSet::iterator i = ne.derivation.outputs.begin(); for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != ne.derivation.outputs.end(); i++) i != goal.expr.derivation.outputs.end(); ++i)
{ {
Path path = *i; Path path = *i;
if (!pathExists(path)) if (!pathExists(path))
@ -193,9 +668,9 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
/* For this output path, find the references to other paths contained /* For this output path, find the references to other paths contained
in it. */ in it. */
startNest(nest2, lvlChatty, startNest(nest2, lvlChatty,
format("scanning for store references in `%1%'") % ne.derivation.builder); format("scanning for store references in `%1%'") % path);
Strings refPaths = filterReferences(path, Strings refPaths = filterReferences(path,
Strings(allPaths.begin(), allPaths.end())); Strings(goal.allPaths.begin(), goal.allPaths.end()));
nest2.close(); nest2.close();
/* Construct a closure element for this output path. */ /* Construct a closure element for this output path. */
@ -205,14 +680,15 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
closure element and add the id to the `usedPaths' set (so that the closure element and add the id to the `usedPaths' set (so that the
elements referenced by *its* closure are added below). */ elements referenced by *its* closure are added below). */
for (Paths::iterator j = refPaths.begin(); for (Paths::iterator j = refPaths.begin();
j != refPaths.end(); j++) j != refPaths.end(); ++j)
{ {
checkInterrupt(); checkInterrupt();
Path path = *j; Path path = *j;
elem.refs.insert(path); elem.refs.insert(path);
if (inClosures.find(path) != inClosures.end()) if (goal.inClosures.find(path) != goal.inClosures.end())
usedPaths.insert(path); usedPaths.insert(path);
else if (ne.derivation.outputs.find(path) == ne.derivation.outputs.end()) else if (goal.expr.derivation.outputs.find(path) ==
goal.expr.derivation.outputs.end())
abort(); abort();
} }
@ -232,8 +708,8 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
if (donePaths.find(path) != donePaths.end()) continue; if (donePaths.find(path) != donePaths.end()) continue;
donePaths.insert(path); donePaths.insert(path);
ClosureElems::iterator j = inClosures.find(path); ClosureElems::iterator j = goal.inClosures.find(path);
if (j == inClosures.end()) abort(); if (j == goal.inClosures.end()) abort();
nf.closure.elems[path] = j->second; nf.closure.elems[path] = j->second;
@ -243,8 +719,8 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
} }
/* For debugging, print out the referenced and unreferenced paths. */ /* For debugging, print out the referenced and unreferenced paths. */
for (ClosureElems::iterator i = inClosures.begin(); for (ClosureElems::iterator i = goal.inClosures.begin();
i != inClosures.end(); i++) i != goal.inClosures.end(); ++i)
{ {
PathSet::iterator j = donePaths.find(i->first); PathSet::iterator j = donePaths.find(i->first);
if (j == donePaths.end()) if (j == donePaths.end())
@ -253,15 +729,13 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
debug(format("referenced input: `%1%'") % i->first); debug(format("referenced input: `%1%'") % i->first);
} }
nest3.close();
/* Write the normal form. This does not have to occur in the /* Write the normal form. This does not have to occur in the
transaction below because writing terms is idem-potent. */ transaction below because writing terms is idem-potent. */
ATerm nfTerm = unparseStoreExpr(nf); ATerm nfTerm = unparseStoreExpr(nf);
printMsg(lvlVomit, format("normal form: %1%") % atPrint(nfTerm)); printMsg(lvlVomit, format("normal form: %1%") % atPrint(nfTerm));
Path nfPath = writeTerm(nfTerm, "-s"); Path nfPath = writeTerm(nfTerm, "-s");
/* Register each outpat path, and register the normal form. This /* Register each output path, and register the normal form. This
is wrapped in one database transaction to ensure that if we is wrapped in one database transaction to ensure that if we
crash, either everything is registered or nothing is. This is crash, either everything is registered or nothing is. This is
for recoverability: unregistered paths in the store can be for recoverability: unregistered paths in the store can be
@ -269,40 +743,79 @@ Path normaliseStoreExpr(const Path & _nePath, PathSet pending)
by running the garbage collector. */ by running the garbage collector. */
Transaction txn; Transaction txn;
createStoreTransaction(txn); createStoreTransaction(txn);
for (PathSet::iterator i = ne.derivation.outputs.begin(); for (PathSet::iterator i = goal.expr.derivation.outputs.begin();
i != ne.derivation.outputs.end(); i++) i != goal.expr.derivation.outputs.end(); ++i)
registerValidPath(txn, *i); registerValidPath(txn, *i);
registerSuccessor(txn, nePath, nfPath); registerSuccessor(txn, goal.nePath, nfPath);
txn.commit(); txn.commit();
/* It is now safe to delete the lock files, since all future /* It is now safe to delete the lock files, since all future
lockers will see the successor; they will not create new lock lockers will see the successor; they will not create new lock
files with the same names as the old (unlinked) lock files. */ files with the same names as the old (unlinked) lock files. */
outputLocks.setDeletion(true); goal.outputLocks.setDeletion(true);
removeGoal(goal);
}
void Normaliser::removeGoal(Goal & goal)
{
/* Remove this goal from those goals to which it is an input. */
for (PathSet::iterator i = goal.waiters.begin();
i != goal.waiters.end(); ++i)
{
Goal & waiter(goals[*i]);
PathSet::iterator j = waiter.unfinishedInputs.find(goal.nePath);
assert(j != waiter.unfinishedInputs.end());
waiter.unfinishedInputs.erase(j);
/* If there are not inputs left, the goal has become
buildable. */
if (waiter.unfinishedInputs.empty()) {
debug(format("waking up goal `%1%'") % waiter.nePath);
buildable.insert(waiter.nePath);
}
}
/* Remove this goal from the graph. Careful: after this `goal' is
probably no longer valid. */
goals.erase(goal.nePath);
}
Path normaliseStoreExpr(const Path & nePath)
{
Normaliser normaliser;
normaliser.addGoal(nePath);
normaliser.run();
Path nfPath;
if (!querySuccessor(nePath, nfPath)) abort();
return nfPath; return nfPath;
} }
void realiseClosure(const Path & nePath, PathSet pending) void realiseClosure(const Path & nePath)
{ {
startNest(nest, lvlDebug, format("realising closure `%1%'") % nePath); startNest(nest, lvlDebug, format("realising closure `%1%'") % nePath);
StoreExpr ne = storeExprFromPath(nePath, pending); StoreExpr ne = storeExprFromPath(nePath);
if (ne.type != StoreExpr::neClosure) if (ne.type != StoreExpr::neClosure)
throw Error(format("expected closure in `%1%'") % nePath); throw Error(format("expected closure in `%1%'") % nePath);
for (ClosureElems::const_iterator i = ne.closure.elems.begin(); for (ClosureElems::const_iterator i = ne.closure.elems.begin();
i != ne.closure.elems.end(); i++) i != ne.closure.elems.end(); ++i)
ensurePath(i->first, pending); ensurePath(i->first);
} }
void ensurePath(const Path & path, PathSet pending) void ensurePath(const Path & path)
{ {
/* If the path is already valid, we're done. */ /* If the path is already valid, we're done. */
if (isValidPath(path)) return; if (isValidPath(path)) return;
#if 0
if (pending.find(path) != pending.end()) if (pending.find(path) != pending.end())
throw Error(format( throw Error(format(
"path `%1%' already being realised (possible substitute cycle?)") "path `%1%' already being realised (possible substitute cycle?)")
@ -313,7 +826,7 @@ void ensurePath(const Path & path, PathSet pending)
Paths subPaths = querySubstitutes(path); Paths subPaths = querySubstitutes(path);
for (Paths::iterator i = subPaths.begin(); for (Paths::iterator i = subPaths.begin();
i != subPaths.end(); i++) i != subPaths.end(); ++i)
{ {
checkInterrupt(); checkInterrupt();
try { try {
@ -327,16 +840,17 @@ void ensurePath(const Path & path, PathSet pending)
% *i % path % e.what()); % *i % path % e.what());
} }
} }
#endif
throw Error(format("path `%1%' is required, " throw Error(format("path `%1%' is required, "
"but there are no (successful) substitutes") % path); "but there are no (successful) substitutes") % path);
} }
StoreExpr storeExprFromPath(const Path & path, PathSet pending) StoreExpr storeExprFromPath(const Path & path)
{ {
assertStorePath(path); assertStorePath(path);
ensurePath(path, pending); ensurePath(path);
ATerm t = ATreadFromNamedFile(path.c_str()); ATerm t = ATreadFromNamedFile(path.c_str());
if (!t) throw Error(format("cannot read aterm from `%1%'") % path); if (!t) throw Error(format("cannot read aterm from `%1%'") % path);
return parseStoreExpr(t); return parseStoreExpr(t);
@ -373,12 +887,12 @@ static void requisitesWorker(const Path & nePath,
if (ne.type == StoreExpr::neClosure) if (ne.type == StoreExpr::neClosure)
for (ClosureElems::iterator i = ne.closure.elems.begin(); for (ClosureElems::iterator i = ne.closure.elems.begin();
i != ne.closure.elems.end(); i++) i != ne.closure.elems.end(); ++i)
paths.insert(i->first); paths.insert(i->first);
else if (ne.type == StoreExpr::neDerivation) else if (ne.type == StoreExpr::neDerivation)
for (PathSet::iterator i = ne.derivation.inputs.begin(); for (PathSet::iterator i = ne.derivation.inputs.begin();
i != ne.derivation.inputs.end(); i++) i != ne.derivation.inputs.end(); ++i)
requisitesWorker(*i, requisitesWorker(*i,
includeExprs, includeSuccessors, paths, doneSet); includeExprs, includeSuccessors, paths, doneSet);

View file

@ -8,7 +8,7 @@
derivation, a path containing an equivalent closure expression is derivation, a path containing an equivalent closure expression is
returned. This requires that the derivation is performed, unless a returned. This requires that the derivation is performed, unless a
successor is known. */ successor is known. */
Path normaliseStoreExpr(const Path & nePath, PathSet pending = PathSet()); Path normaliseStoreExpr(const Path & nePath);
/* Realise a closure store expression in the file system. /* Realise a closure store expression in the file system.
@ -16,15 +16,15 @@ Path normaliseStoreExpr(const Path & nePath, PathSet pending = PathSet());
prevents infinite recursion for paths realised through a substitute prevents infinite recursion for paths realised through a substitute
(since when we build the substitute, we would first try to realise (since when we build the substitute, we would first try to realise
its output paths through substitutes... kaboom!). */ its output paths through substitutes... kaboom!). */
void realiseClosure(const Path & nePath, PathSet pending = PathSet()); void realiseClosure(const Path & nePath);
/* Ensure that a path exists, possibly by instantiating it by /* Ensure that a path exists, possibly by instantiating it by
realising a substitute. */ realising a substitute. */
void ensurePath(const Path & path, PathSet pending = PathSet()); void ensurePath(const Path & path);
/* Read a store expression, after ensuring its existence through /* Read a store expression, after ensuring its existence through
ensurePath(). */ ensurePath(). */
StoreExpr storeExprFromPath(const Path & path, PathSet pending = PathSet()); StoreExpr storeExprFromPath(const Path & path);
/* Get the list of root (output) paths of the given store /* Get the list of root (output) paths of the given store
expression. */ expression. */

View file

@ -45,9 +45,24 @@ bool lockFile(int fd, LockType lockType, bool wait)
static StringSet lockedPaths; /* !!! not thread-safe */ static StringSet lockedPaths; /* !!! not thread-safe */
PathLocks::PathLocks(const PathSet & _paths) PathLocks::PathLocks()
: deletePaths(false) : deletePaths(false)
{ {
}
PathLocks::PathLocks(const PathSet & paths)
: deletePaths(false)
{
lockPaths(paths);
}
void PathLocks::lockPaths(const PathSet & _paths)
{
/* May be called only once! */
assert(this->paths.empty());
/* Note that `fds' is built incrementally so that the destructor /* Note that `fds' is built incrementally so that the destructor
will only release those locks that we have already acquired. */ will only release those locks that we have already acquired. */
@ -80,6 +95,8 @@ PathLocks::PathLocks(const PathSet & _paths)
/* Acquire an exclusive lock. */ /* Acquire an exclusive lock. */
lockFile(fd, ltWrite, true); lockFile(fd, ltWrite, true);
debug(format("lock acquired on `%1%'") % lockPath);
lockedPaths.insert(lockPath); lockedPaths.insert(lockPath);
} }
} }
@ -88,7 +105,7 @@ PathLocks::PathLocks(const PathSet & _paths)
PathLocks::~PathLocks() PathLocks::~PathLocks()
{ {
for (list<int>::iterator i = fds.begin(); i != fds.end(); i++) for (list<int>::iterator i = fds.begin(); i != fds.end(); i++)
close(*i); if (close(*i) != 0) throw SysError("closing fd");
for (Paths::iterator i = paths.begin(); i != paths.end(); i++) { for (Paths::iterator i = paths.begin(); i != paths.end(); i++) {
checkInterrupt(); checkInterrupt();
@ -99,6 +116,7 @@ PathLocks::~PathLocks()
the lock file is an optimisation, not a necessity. */ the lock file is an optimisation, not a necessity. */
} }
lockedPaths.erase(*i); lockedPaths.erase(*i);
debug(format("lock released on `%1%'") % *i);
} }
} }

View file

@ -17,7 +17,9 @@ private:
bool deletePaths; bool deletePaths;
public: public:
PathLocks(const PathSet & _paths); PathLocks();
PathLocks(const PathSet & paths);
void lockPaths(const PathSet & _paths);
~PathLocks(); ~PathLocks();
void setDeletion(bool deletePaths); void setDeletion(bool deletePaths);
}; };

View file

@ -17,10 +17,9 @@ dependencies.sh: dependencies.nix
locking.sh: locking.nix locking.sh: locking.nix
parallel.sh: parallel.nix parallel.sh: parallel.nix
TESTS = init.sh simple.sh dependencies.sh parallel.sh TESTS = init.sh simple.sh dependencies.sh locking.sh parallel.sh
#locking.sh parallel.sh
XFAIL_TESTS = parallel.sh XFAIL_TESTS =
include ../substitute.mk include ../substitute.mk

View file

@ -4,7 +4,7 @@ echo "store expr is $storeExpr"
for i in $(seq 1 5); do for i in $(seq 1 5); do
echo "WORKER $i" echo "WORKER $i"
$TOP/src/nix-store/nix-store -rvvB "$storeExpr" & $TOP/src/nix-store/nix-store -rvvvvvB "$storeExpr" &
done done
sleep 5 sleep 5

View file

@ -11,9 +11,9 @@ let {
a = mkDrv "a" []; a = mkDrv "a" [];
b = mkDrv "b" [a]; b = mkDrv "b" [a];
c = mkDrv "c" [b]; c = mkDrv "c" [a];
d = mkDrv "d" [c]; d = mkDrv "d" [a];
e = mkDrv "e" [b c d]; e = mkDrv "e" [b c d];
body = e; body = e;
} }

View file

@ -2,19 +2,19 @@ storeExpr=$($TOP/src/nix-instantiate/nix-instantiate parallel.nix)
echo "store expr is $storeExpr" echo "store expr is $storeExpr"
for i in $(seq 1 5); do #for i in $(seq 1 5); do
echo "WORKER $i" # echo "WORKER $i"
$TOP/src/nix-store/nix-store -rvvB "$storeExpr" & # $TOP/src/nix-store/nix-store -rvvB "$storeExpr" &
done #done
sleep 5 #sleep 5
outPath=$($TOP/src/nix-store/nix-store -qnfvvvvv "$storeExpr") outPath=$($TOP/src/nix-store/nix-store -qnfvvvvvvK "$storeExpr")
echo "output path is $outPath" echo "output path is $outPath"
text=$(cat "$outPath") text=$(cat "$outPath")
if test "$text" != "aabcade"; then exit 1; fi if test "$text" != "abacade"; then exit 1; fi
if test "$(cat $SHARED.cur)" != 0; then exit 1; fi if test "$(cat $SHARED.cur)" != 0; then exit 1; fi
if test "$(cat $SHARED.max)" != 3; then exit 1; fi if test "$(cat $SHARED.max)" != 3; then exit 1; fi