The childinfo_t union shares the 'long long error' member with a
'pthread_t threadid'. For a "sufficiently large" threadid, it's
possible that the error condition is incorrectly hit even though a valid
thread was created.
Stop conflating the error condition with legitimate thread/process
identifiers by modifying create_worker to explicitly return an error
code.
Inspired by a patch in OpenEmbedded authored by Song Li and Jesse Zhang.
Cc: Song.Li <Song.Li@xxxxxxxxxxxxx>
Cc: Jesse Zhang <sen.zhang@xxxxxxxxxxxxx>
Signed-off-by: Josh Cartwright <joshc@xxxxxx>
---
src/hackbench/hackbench.c | 36 +++++++++++++++---------------------
1 file changed, 15 insertions(+), 21 deletions(-)
diff --git a/src/hackbench/hackbench.c b/src/hackbench/hackbench.c
index c42257c..ba804f5 100644
--- a/src/hackbench/hackbench.c
+++ b/src/hackbench/hackbench.c
@@ -64,7 +64,6 @@ struct receiver_context {
typedef union {
pthread_t threadid;
pid_t pid;
- long long error;
} childinfo_t;
childinfo_t *child_tab = NULL;
@@ -189,52 +188,44 @@ again:
return NULL;
}
-static childinfo_t create_worker(void *ctx, void *(*func)(void *))
+static int create_worker(childinfo_t *child, void *ctx, void *(*func)(void *))
{
pthread_attr_t attr;
int err;
- childinfo_t child;
- pid_t childpid;
- memset(&child, 0, sizeof(child));
switch (process_mode) {
case PROCESS_MODE: /* process mode */
/* Fork the sender/receiver child. */
- switch ((childpid = fork())) {
+ switch ((child->pid = fork())) {
case -1:
sneeze("fork()");
- child.error = -1;
- return child;
+ return -1;
case 0:
(*func) (ctx);
exit(0);
}
- child.pid = childpid;
break;
case THREAD_MODE: /* threaded mode */
if (pthread_attr_init(&attr) != 0) {
sneeze("pthread_attr_init()");
- child.error = -1;
- return child;
+ return -1;
}
#ifndef __ia64__
if (pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN) != 0) {
sneeze("pthread_attr_setstacksize()");
- child.error = -1;
- return child;
+ return -1;
}
#endif
- if ((err=pthread_create(&child.threadid, &attr, func, ctx)) != 0) {
+ if ((err=pthread_create(&child->threadid, &attr, func, ctx)) != 0) {
sneeze("pthread_create failed()");
- child.error = -1;
- return child;
+ return -1;
}
break;
}
- return child;
+ return 0;
}
void signal_workers(childinfo_t *children, unsigned int num_children)
@@ -291,6 +282,7 @@ static unsigned int group(childinfo_t *child,
unsigned int i;
struct sender_context* snd_ctx = malloc (sizeof(struct sender_context)
+num_fds*sizeof(int));
+ int err;
if (!snd_ctx) {
sneeze("malloc() [sender ctx]");
@@ -317,8 +309,9 @@ static unsigned int group(childinfo_t *child,
ctx->ready_out = ready_out;
ctx->wakefd = wakefd;
- child[tab_offset+i] = create_worker(ctx, (void *)(void *)receiver);
- if( child[tab_offset+i].error < 0 ) {
+ err = create_worker(&child[tab_offset+i], ctx,
+ (void *)(void *)receiver);
+ if(err) {
return (i > 0 ? i-1 : 0);
}
snd_ctx->out_fds[i] = fds[1];
@@ -332,8 +325,9 @@ static unsigned int group(childinfo_t *child,
/* Now we have all the fds, fork the senders */
for (i = 0; i < num_fds; i++) {
- child[tab_offset+num_fds+i] = create_worker(snd_ctx, (void *)(void *)sender);
- if( child[tab_offset+num_fds+i].error < 0 ) {
+ err = create_worker(&child[tab_offset+num_fds+i], snd_ctx,
+ (void *)(void *)sender);
+ if(err) {
return (num_fds+i)-1;
}
}
--
2.5.0
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