From: Herbert Xu <herbert@gondor.apana.org.au>
To: dash@vger.kernel.org
Subject: [PATCH] jobs: Fix waitcmd busy loop
Date: Tue, 2 Jun 2020 23:46:48 +1000 [thread overview]
Message-ID: <20200602134648.GA17275@gondor.apana.org.au> (raw)
We need to clear gotsigchld in waitproc because it is used as
a loop conditional for the waitcmd case. Without it waitcmd
may busy loop after a SIGCHLD.
This patch also changes gotsigchld into a volatile sig_atomic_t
to prevent compilers from optimising its accesses away.
Fixes: 6c691b3e5099 ("jobs: Only clear gotsigchld when waiting...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/src/jobs.c b/src/jobs.c
index 94bf47e..3417633 100644
--- a/src/jobs.c
+++ b/src/jobs.c
@@ -1135,7 +1135,6 @@ static int dowait(int block, struct job *jp)
rpid = 1;
do {
- gotsigchld = 0;
pid = waitone(block, jp);
rpid &= !!pid;
@@ -1175,6 +1174,7 @@ waitproc(int block, int *status)
#endif
do {
+ gotsigchld = 0;
do
err = wait3(status, flags, NULL);
while (err < 0 && errno == EINTR);
diff --git a/src/trap.c b/src/trap.c
index 82e7ece..cd84814 100644
--- a/src/trap.c
+++ b/src/trap.c
@@ -76,7 +76,7 @@ static char gotsig[NSIG - 1];
/* last pending signal */
volatile sig_atomic_t pending_sig;
/* received SIGCHLD */
-int gotsigchld;
+volatile sig_atomic_t gotsigchld;
extern char *signal_names[];
diff --git a/src/trap.h b/src/trap.h
index 4c455a8..beaf660 100644
--- a/src/trap.h
+++ b/src/trap.h
@@ -39,7 +39,7 @@
extern int trapcnt;
extern char sigmode[];
extern volatile sig_atomic_t pending_sig;
-extern int gotsigchld;
+extern volatile sig_atomic_t gotsigchld;
int trapcmd(int, char **);
void setsignal(int);
--
Email: Herbert Xu <herbert@gondor.apana.org.au>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
reply other threads:[~2020-06-02 13:46 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20200602134648.GA17275@gondor.apana.org.au \
--to=herbert@gondor.apana.org.au \
--cc=dash@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).