[PATCH] PKTGEN: Fix module load/unload races.

Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index 733d86d0a4fb7f3b97a2ae23291c34281fe4f2c8..261f8fb6a5c567dfdb6258718a83100e939a4b52 100644 (file)
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -147,6 +147,7 @@
 #include <linux/proc_fs.h>
 #include <linux/seq_file.h>
 #include <linux/wait.h>
+#include <linux/completion.h>
 #include <linux/etherdevice.h>
 #include <net/checksum.h>
 #include <net/ipv6.h>
@@ -206,6 +207,11 @@ static struct proc_dir_entry *pg_proc_dir = NULL;
 #define VLAN_TAG_SIZE(x) ((x)->vlan_id == 0xffff ? 0 : 4)
 #define SVLAN_TAG_SIZE(x) ((x)->svlan_id == 0xffff ? 0 : 4)
 
+struct pktgen_thread_info {
+       struct pktgen_thread *t;
+       struct completion *c;
+};
+
 struct flow_state {
        __u32 cur_daddr;
        int count;
@@ -3264,10 +3270,11 @@ out:;
  * Main loop of the thread goes here
  */
 
-static void pktgen_thread_worker(struct pktgen_thread *t)
+static void pktgen_thread_worker(struct pktgen_thread_info *info)
 {
        DEFINE_WAIT(wait);
        struct pktgen_dev *pkt_dev = NULL;
+       struct pktgen_thread *t = info->t;
        int cpu = t->cpu;
        sigset_t tmpsig;
        u32 max_before_softirq;
@@ -3307,6 +3314,8 @@ static void pktgen_thread_worker(struct pktgen_thread *t)
        __set_current_state(TASK_INTERRUPTIBLE);
        mb();
 
+        complete(info->c);
+
        while (1) {
 
                __set_current_state(TASK_RUNNING);
@@ -3518,6 +3527,8 @@ static struct pktgen_thread *__init pktgen_find_thread(const char *name)
 static int __init pktgen_create_thread(const char *name, int cpu)
 {
        int err;
+       struct pktgen_thread_info info;
+        struct completion started;
        struct pktgen_thread *t = NULL;
        struct proc_dir_entry *pe;
 
@@ -3558,7 +3569,11 @@ static int __init pktgen_create_thread(const char *name, int cpu)
 
        t->removed = 0;
 
-       err = kernel_thread((void *)pktgen_thread_worker, (void *)t,
+       init_completion(&started);
+        info.t = t;
+        info.c = &started;
+
+       err = kernel_thread((void *)pktgen_thread_worker, (void *)&info,
                          CLONE_FS | CLONE_FILES | CLONE_SIGHAND);
        if (err < 0) {
                printk("pktgen: kernel_thread() failed for cpu %d\n", t->cpu);
@@ -3568,6 +3583,7 @@ static int __init pktgen_create_thread(const char *name, int cpu)
                return err;
        }
 
+       wait_for_completion(&started);
        return 0;
 }