Use a non-blocking read with pselect to avoid hangs. BZ #1556839
Merges upstream git b552b05251980f693c729e251f93f5225b400714 https://savannah.gnu.org/bugs/?51159
This commit is contained in:
DJ Delorie
parent
a58f35f819
commit
b119ff1512
164
make-4.2.1-nonblocking-reads.patch
Normal file
164
make-4.2.1-nonblocking-reads.patch
Normal file
@ -0,0 +1,164 @@
|
||||
From b552b05251980f693c729e251f93f5225b400714 Mon Sep 17 00:00:00 2001
|
||||
From: Paul Smith <psmith@gnu.org>
|
||||
Date: Sat, 3 Jun 2017 16:20:51 -0400
|
||||
Subject: [SV 51159] Use a non-blocking read with pselect to avoid hangs.
|
||||
|
||||
* posixos.c (set_blocking): Set blocking on a file descriptor.
|
||||
(jobserver_setup): Set non-blocking on the jobserver read side.
|
||||
(jobserver_parse_auth): Ditto.
|
||||
(jobserver_acquire_all): Set blocking to avoid a busy-wait loop.
|
||||
(jobserver_acquire): If the non-blocking read() returns without
|
||||
taking a token then try again.
|
||||
|
||||
diff --git a/posixos.c b/posixos.c
|
||||
index e642d7f..dbafa51 100644
|
||||
--- a/posixos.c
|
||||
+++ b/posixos.c
|
||||
@@ -62,6 +62,24 @@ make_job_rfd (void)
|
||||
#endif
|
||||
}
|
||||
|
||||
+static void
|
||||
+set_blocking (int fd, int blocking)
|
||||
+{
|
||||
+ // If we're not using pselect() don't change the blocking
|
||||
+#ifdef HAVE_PSELECT
|
||||
+ int flags;
|
||||
+ EINTRLOOP (flags, fcntl (fd, F_GETFL));
|
||||
+ if (flags >= 0)
|
||||
+ {
|
||||
+ int r;
|
||||
+ flags = blocking ? (flags & ~O_NONBLOCK) : (flags | O_NONBLOCK);
|
||||
+ EINTRLOOP (r, fcntl (fd, F_SETFL, flags));
|
||||
+ if (r < 0)
|
||||
+ pfatal_with_name ("fcntl(O_NONBLOCK)");
|
||||
+ }
|
||||
+#endif
|
||||
+}
|
||||
+
|
||||
unsigned int
|
||||
jobserver_setup (int slots)
|
||||
{
|
||||
@@ -86,6 +104,9 @@ jobserver_setup (int slots)
|
||||
pfatal_with_name (_("init jobserver pipe"));
|
||||
}
|
||||
|
||||
+ /* When using pselect() we want the read to be non-blocking. */
|
||||
+ set_blocking (job_fds[0], 0);
|
||||
+
|
||||
return 1;
|
||||
}
|
||||
|
||||
@@ -121,6 +142,9 @@ jobserver_parse_auth (const char *auth)
|
||||
return 0;
|
||||
}
|
||||
|
||||
+ /* When using pselect() we want the read to be non-blocking. */
|
||||
+ set_blocking (job_fds[0], 0);
|
||||
+
|
||||
return 1;
|
||||
}
|
||||
|
||||
@@ -169,7 +193,10 @@ jobserver_acquire_all (void)
|
||||
{
|
||||
unsigned int tokens = 0;
|
||||
|
||||
- /* Close the write side, so the read() won't hang. */
|
||||
+ /* Use blocking reads to wait for all outstanding jobs. */
|
||||
+ set_blocking (job_fds[0], 1);
|
||||
+
|
||||
+ /* Close the write side, so the read() won't hang forever. */
|
||||
close (job_fds[1]);
|
||||
job_fds[1] = -1;
|
||||
|
||||
@@ -236,18 +263,12 @@ jobserver_pre_acquire (void)
|
||||
unsigned int
|
||||
jobserver_acquire (int timeout)
|
||||
{
|
||||
- sigset_t empty;
|
||||
- fd_set readfds;
|
||||
struct timespec spec;
|
||||
struct timespec *specp = NULL;
|
||||
- int r;
|
||||
- char intake;
|
||||
+ sigset_t empty;
|
||||
|
||||
sigemptyset (&empty);
|
||||
|
||||
- FD_ZERO (&readfds);
|
||||
- FD_SET (job_fds[0], &readfds);
|
||||
-
|
||||
if (timeout)
|
||||
{
|
||||
/* Alarm after one second (is this too granular?) */
|
||||
@@ -256,28 +277,52 @@ jobserver_acquire (int timeout)
|
||||
specp = &spec;
|
||||
}
|
||||
|
||||
- r = pselect (job_fds[0]+1, &readfds, NULL, NULL, specp, &empty);
|
||||
-
|
||||
- if (r == -1)
|
||||
+ while (1)
|
||||
{
|
||||
- /* Better be SIGCHLD. */
|
||||
- if (errno != EINTR)
|
||||
- pfatal_with_name (_("pselect jobs pipe"));
|
||||
- return 0;
|
||||
- }
|
||||
+ fd_set readfds;
|
||||
+ int r;
|
||||
+ char intake;
|
||||
|
||||
- if (r == 0)
|
||||
- /* Timeout. */
|
||||
- return 0;
|
||||
+ FD_ZERO (&readfds);
|
||||
+ FD_SET (job_fds[0], &readfds);
|
||||
|
||||
- /* The read FD is ready: read it! */
|
||||
- EINTRLOOP (r, read (job_fds[0], &intake, 1));
|
||||
- if (r < 0)
|
||||
- pfatal_with_name (_("read jobs pipe"));
|
||||
+ r = pselect (job_fds[0]+1, &readfds, NULL, NULL, specp, &empty);
|
||||
+ if (r < 0)
|
||||
+ switch (errno)
|
||||
+ {
|
||||
+ case EINTR:
|
||||
+ /* SIGCHLD will show up as an EINTR. */
|
||||
+ return 0;
|
||||
+
|
||||
+ case EBADF:
|
||||
+ /* Someone closed the jobs pipe.
|
||||
+ That shouldn't happen but if it does we're done. */
|
||||
+ O (fatal, NILF, _("job server shut down"));
|
||||
|
||||
- /* What does it mean if read() returns 0? It shouldn't happen because only
|
||||
- the master make can reap all the tokens and close the write side...?? */
|
||||
- return r > 0;
|
||||
+ default:
|
||||
+ pfatal_with_name (_("pselect jobs pipe"));
|
||||
+ }
|
||||
+
|
||||
+ if (r == 0)
|
||||
+ /* Timeout. */
|
||||
+ return 0;
|
||||
+
|
||||
+ /* The read FD is ready: read it! This is non-blocking. */
|
||||
+ EINTRLOOP (r, read (job_fds[0], &intake, 1));
|
||||
+
|
||||
+ if (r < 0)
|
||||
+ {
|
||||
+ /* Someone sniped our token! Try again. */
|
||||
+ if (errno == EAGAIN)
|
||||
+ continue;
|
||||
+
|
||||
+ pfatal_with_name (_("read jobs pipe"));
|
||||
+ }
|
||||
+
|
||||
+ /* read() should never return 0: only the master make can reap all the
|
||||
+ tokens and close the write side...?? */
|
||||
+ return r > 0;
|
||||
+ }
|
||||
}
|
||||
|
||||
#else
|
||||
@ -3,7 +3,7 @@ Summary: A GNU tool which simplifies the build process for users
|
||||
Name: make
|
||||
Epoch: 1
|
||||
Version: 4.2.1
|
||||
Release: 14%{?dist}
|
||||
Release: 15%{?dist}
|
||||
License: GPLv3+
|
||||
URL: http://www.gnu.org/software/make/
|
||||
Source: ftp://ftp.gnu.org/gnu/make/make-%{version}.tar.bz2
|
||||
@ -38,6 +38,10 @@ Patch8: make-4.2.1-test-driver.patch
|
||||
# Adds support of guile 2.2
|
||||
Patch9: 0001-configure.ac-SV-50648-Detect-Guile-2.2-packages.patch
|
||||
|
||||
# Upstream patch: https://git.savannah.gnu.org/cgit/make.git/commit/?id=b552b05251980f693c729e251f93f5225b400714
|
||||
# Avoids hangs in parallel builds
|
||||
Patch10: make-4.2.1-nonblocking-reads.patch
|
||||
|
||||
# autoreconf
|
||||
BuildRequires: autoconf, automake, gettext-devel
|
||||
BuildRequires: procps
|
||||
@ -95,6 +99,9 @@ echo ============END TESTING===========
|
||||
%{_includedir}/gnumake.h
|
||||
|
||||
%changelog
|
||||
* Fri Dec 06 2019 DJ Delorie <dj@redhat.com> - 1:4.2.1-15
|
||||
- Use a non-blocking read with pselect to avoid hangs. BZ #1556839
|
||||
|
||||
* Thu Jul 25 2019 Fedora Release Engineering <releng@fedoraproject.org> - 1:4.2.1-14
|
||||
- Rebuilt for https://fedoraproject.org/wiki/Fedora_31_Mass_Rebuild
|
||||
|
||||
|
||||
Loading…
Reference in New Issue
Block a user