Changeset cd37cdc for libwandio/ior-thread.c

Timestamp:

04/01/15 11:37:41 (6 years ago)

Author:

Shane Alcock <salcock@…>

Branches:

4.0.1-hotfixes, cachetimestamps, develop, dpdk-ndag, etsilive, libtrace4, master, ndag_format, pfring, rc-4.0.1, rc-4.0.2, rc-4.0.3, rc-4.0.4, ringdecrementfix, ringperformance, ringtimestampfixes

Children:

03f8943

Parents:

3e5518a

Message:

Block all signals in libwandio threads.

It is probably better for the main processing thread(s) to do
signal handling, rather than libwandio threads. This fixes a potential
race condition reported by helgrind for tracestats (and presumably
other tools) where the libwandio thread could modify the 'done' flag
while the main thread was checking it.

File:

• libwandio/ior-thread.c (modified) (4 diffs)

libwandio/ior-thread.c

@@ -44 +44 @@
 #include <stdbool.h>
 #include <errno.h>
+#include <signal.h>
 #ifdef HAVE_SYS_PRCTL_H
 #include <sys/prctl.h>
@@ -167 +168 @@
 {
         io_t *state;
+        sigset_t set;
+        int s;
 
         if (!parent) {
@@ -172 +175 @@
         }
         
-
+        sigfillset(&set);
         state = malloc(sizeof(io_t));
         state->data = calloc(1,sizeof(struct state_t));
@@ -189 +192 @@
 
         /* Create the reading thread */
+        s = pthread_sigmask(SIG_SETMASK, &set, NULL);
         pthread_create(&DATA(state)->producer,NULL,thread_producer,state);
+        sigemptyset(&set);
+        s = pthread_sigmask(SIG_SETMASK, &set, NULL);
 
         return state;