Date: Thu, 11 Nov 2004 20:42:21 +0100 From: Poul-Henning Kamp <phk@phk.freebsd.dk> To: current@freebsd.org Subject: [TEST] make -j patch Message-ID: <80546.1100202141@critter.freebsd.dk>
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This patch makes the '-j' argument to make(1) become a global limit
on number of jobs launched for all submakes in the build.
Today a "make -j 12" may start many more than 12 jobs because each
submake interprets the 12 without reference to other makes.
The patch uses a fifo to hold tokens allowing jobstarts.
Poul-Henning
Index: job.c
===================================================================
RCS file: /home/ncvs/src/usr.bin/make/job.c,v
retrieving revision 1.55
diff -u -r1.55 job.c
--- job.c 11 Nov 2004 12:52:15 -0000 1.55
+++ job.c 11 Nov 2004 19:15:30 -0000
@@ -258,6 +258,8 @@
* jobs that were stopped due to concurrency
* limits or externally */
+STATIC int fifoFd; /* Fd of our job fifo */
+STATIC char fifoName[] = "/tmp/make_fifo_XXXXXXXXX";
#if defined(USE_PGRP) && defined(SYSV)
# define KILL(pid, sig) killpg(-(pid), (sig))
@@ -1091,6 +1093,8 @@
Punt("Cannot fork");
} else if (cpid == 0) {
+ if (fifoFd >= 0)
+ close(fifoFd);
/*
* Must duplicate the input stream down to the child's input and
* reset it to the beginning (again). Since the stream was marked
@@ -1891,9 +1895,10 @@
return;
}
- while ((pid = waitpid((pid_t) -1, &status,
- (block?0:WNOHANG)|WUNTRACED)) > 0)
- {
+ for (;;) {
+ pid = waitpid((pid_t) -1, &status, (block?0:WNOHANG)|WUNTRACED);
+ if (pid <= 0)
+ break;
DEBUGF(JOB, ("Process %d exited or stopped.\n", pid));
jnode = Lst_Find(jobs, (void *)&pid, JobCmpPid);
@@ -1915,8 +1920,17 @@
job = (Job *) Lst_Datum(jnode);
(void) Lst_Remove(jobs, jnode);
nJobs -= 1;
- DEBUGF(JOB, ("Job queue is no longer full.\n"));
- jobFull = FALSE;
+ if (fifoFd >= 0 && nJobs > 0) {
+ write(fifoFd, "+", 1);
+ maxJobs--;
+ if (nJobs >= maxJobs)
+ jobFull = TRUE;
+ else
+ jobFull = FALSE;
+ } else {
+ DEBUGF(JOB, ("Job queue is no longer full.\n"));
+ jobFull = FALSE;
+ }
}
JobFinish(job, &status);
@@ -1982,23 +1996,28 @@
readfds = outputs;
timeout.tv_sec = SEL_SEC;
timeout.tv_usec = SEL_USEC;
+ if (jobFull && fifoFd >= 0)
+ FD_SET(fifoFd, &readfds);
- if ((nfds = select(FD_SETSIZE, &readfds, (fd_set *) 0,
- (fd_set *) 0, &timeout)) <= 0)
+ nfds = select(FD_SETSIZE, &readfds, (fd_set *) 0,
+ (fd_set *) 0, &timeout);
+ if (nfds <= 0)
return;
- else {
- if (Lst_Open(jobs) == FAILURE) {
- Punt("Cannot open job table");
- }
- while (nfds && (ln = Lst_Next(jobs)) != NULL) {
- job = (Job *) Lst_Datum(ln);
- if (FD_ISSET(job->inPipe, &readfds)) {
- JobDoOutput(job, FALSE);
- nfds -= 1;
- }
+ if (fifoFd >= 0 && FD_ISSET(fifoFd, &readfds)) {
+ if (--nfds <= 0)
+ return;
+ }
+ if (Lst_Open(jobs) == FAILURE) {
+ Punt("Cannot open job table");
+ }
+ while (nfds && (ln = Lst_Next(jobs)) != NULL) {
+ job = (Job *) Lst_Datum(ln);
+ if (FD_ISSET(job->inPipe, &readfds)) {
+ JobDoOutput(job, FALSE);
+ nfds -= 1;
}
- Lst_Close(jobs);
}
+ Lst_Close(jobs);
#endif /* !USE_KQUEUE */
}
}
@@ -2055,19 +2074,62 @@
Job_Init(int maxproc)
{
GNode *begin; /* node for commands to do at the very start */
+ const char *env;
+ fifoFd = -1;
jobs = Lst_Init(FALSE);
stoppedJobs = Lst_Init(FALSE);
- maxJobs = maxproc;
+ env = getenv("MAKE_JOBS_FIFO");
+ if (env == NULL && maxproc > 1) {
+ /*
+ * We did not find the environment variable so we are the leader.
+ * Create the fifo, open it, write one char per allowed job into
+ * the pipe.
+ */
+ mktemp(fifoName);
+ if (!mkfifo(fifoName, 0600)) {
+ fifoFd = open(fifoName, O_RDWR | O_NONBLOCK, 0);
+ if (fifoFd >= 0) {
+ fcntl(fifoFd, F_SETFL, O_NONBLOCK);
+ env = fifoName;
+ setenv("MAKE_JOBS_FIFO", env, 1);
+ while (maxproc-- > 0)
+ write(fifoFd, "+", 1);
+ /*The master make does not get a magic token */
+ jobFull = TRUE;
+ maxJobs = 0;
+ } else {
+ unlink(fifoName);
+ env = NULL;
+ }
+ }
+ } else if (env != NULL) {
+ /*
+ * We had the environment variable so we are a slave.
+ * Open fifo and give ourselves a magic token which represents
+ * the token our parent make has grabbed to start his make process.
+ * Otherwise the sub-makes would gobble up tokens and the proper
+ * number of tokens to specify to -j would depend on the depth of * the tree and the order of execution.
+ */
+ fifoFd = open(env, O_RDWR, 0);
+ if (fifoFd >= 0) {
+ fcntl(fifoFd, F_SETFL, O_NONBLOCK);
+ maxJobs = 1;
+ jobFull = FALSE;
+ }
+ }
+ if (fifoFd <= 0) {
+ maxJobs = maxproc;
+ jobFull = FALSE;
+ }
nJobs = 0;
- jobFull = FALSE;
aborting = 0;
errors = 0;
lastNode = NULL;
- if (maxJobs == 1 || beVerbose == 0) {
+ if ((maxJobs == 1 && fifoFd < 0) || beVerbose == 0) {
/*
* If only one job can run at a time, there's no need for a banner,
* no is there?
@@ -2157,7 +2219,19 @@
Boolean
Job_Full(void)
{
- return(aborting || jobFull);
+ char c;
+ int i;
+
+ if (aborting)
+ return(aborting);
+ if (fifoFd >= 0 && jobFull) {
+ i = read(fifoFd, &c, 1);
+ if (i > 0) {
+ maxJobs++;
+ jobFull = FALSE;
+ }
+ }
+ return(jobFull);
}
/*-
@@ -2485,6 +2559,8 @@
}
}
}
+ if (fifoFd >= 0)
+ unlink(fifoName);
return(errors);
}
Index: make.c
===================================================================
RCS file: /home/ncvs/src/usr.bin/make/make.c,v
retrieving revision 1.24
diff -u -r1.24 make.c
--- make.c 23 Oct 2002 23:16:43 -0000 1.24
+++ make.c 11 Nov 2004 14:36:35 -0000
@@ -637,7 +637,7 @@
{
GNode *gn;
- while (!Job_Full() && !Lst_IsEmpty (toBeMade)) {
+ while (!Lst_IsEmpty (toBeMade) && !Job_Full()) {
gn = (GNode *) Lst_DeQueue (toBeMade);
DEBUGF(MAKE, ("Examining %s...", gn->name));
/*
--
Poul-Henning Kamp | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG | TCP/IP since RFC 956
FreeBSD committer | BSD since 4.3-tahoe
Never attribute to malice what can adequately be explained by incompetence.
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