[PKTGEN]: Ports thread list to Kernel list implementation.

The final result is a simpler and smaller code.

Note that I'm adding a new member in the struct pktgen_thread called
'removed'. The reason is that I didn't find a better wait condition to
be used in the place of the replaced one.

Signed-off-by: Luiz Capitulino <lcapitulino@mandriva.com.br>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 41 insertions, 55 deletions

diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index e49b006a7654..f2c0e965c139 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -125,6 +125,7 @@
 #include <linux/capability.h>
 #include <linux/delay.h>
 #include <linux/timer.h>
+#include <linux/list.h>
 #include <linux/init.h>
 #include <linux/skbuff.h>
 #include <linux/netdevice.h>
@@ -330,7 +331,8 @@ struct pktgen_hdr {
 struct pktgen_thread {
         spinlock_t if_lock;
         struct pktgen_dev *if_list;     /* All device here */
-        struct pktgen_thread *next;
+        struct list_head th_list;
+        int removed;
         char name[32];
         char result[512];
         u32 max_before_softirq; /* We'll call do_softirq to prevent starvation. */
@@ -492,7 +494,7 @@ static int pg_clone_skb_d;
 static int debug;
 
 static DECLARE_MUTEX(pktgen_sem);
-static struct pktgen_thread *pktgen_threads = NULL;
+static LIST_HEAD(pktgen_threads);
 
 static struct notifier_block pktgen_notifier_block = {
         .notifier_call = pktgen_device_event,
@@ -1522,9 +1524,7 @@ static struct pktgen_dev *__pktgen_NN_threads(const char *ifname, int remove)
         struct pktgen_thread *t;
         struct pktgen_dev *pkt_dev = NULL;
 
-        t = pktgen_threads;
-
-        while (t) {
+        list_for_each_entry(t, &pktgen_threads, th_list) {
                 pkt_dev = pktgen_find_dev(t, ifname);
                 if (pkt_dev) {
                         if (remove) {
@@ -1535,7 +1535,6 @@ static struct pktgen_dev *__pktgen_NN_threads(const char *ifname, int remove)
                         }
                         break;
                 }
-                t = t->next;
         }
         return pkt_dev;
 }
@@ -2455,15 +2454,15 @@ static void pktgen_run(struct pktgen_thread *t)
 
 static void pktgen_stop_all_threads_ifs(void)
 {
-        struct pktgen_thread *t = pktgen_threads;
+        struct pktgen_thread *t;
 
         PG_DEBUG(printk("pktgen: entering pktgen_stop_all_threads_ifs.\n"));
 
         thread_lock();
-        while (t) {
+
+        list_for_each_entry(t, &pktgen_threads, th_list)
                 t->control |= T_STOP;
-                t = t->next;
-        }
+
         thread_unlock();
 }
 
@@ -2503,40 +2502,36 @@ signal:
 
 static int pktgen_wait_all_threads_run(void)
 {
-        struct pktgen_thread *t = pktgen_threads;
+        struct pktgen_thread *t;
         int sig = 1;
 
-        while (t) {
+        thread_lock();
+
+        list_for_each_entry(t, &pktgen_threads, th_list) {
                 sig = pktgen_wait_thread_run(t);
                 if (sig == 0)
                         break;
-                thread_lock();
-                t = t->next;
-                thread_unlock();
         }
-        if (sig == 0) {
-                thread_lock();
-                while (t) {
+
+        if (sig == 0)
+                list_for_each_entry(t, &pktgen_threads, th_list)
                         t->control |= (T_STOP);
-                        t = t->next;
-                }
-                thread_unlock();
-        }
+
+        thread_unlock();
         return sig;
 }
 
 static void pktgen_run_all_threads(void)
 {
-        struct pktgen_thread *t = pktgen_threads;
+        struct pktgen_thread *t;
 
         PG_DEBUG(printk("pktgen: entering pktgen_run_all_threads.\n"));
 
         thread_lock();
 
-        while (t) {
+        list_for_each_entry(t, &pktgen_threads, th_list)
                 t->control |= (T_RUN);
-                t = t->next;
-        }
+
         thread_unlock();
 
         schedule_timeout_interruptible(msecs_to_jiffies(125));  /* Propagate thread->control  */
@@ -2693,24 +2688,12 @@ static void pktgen_rem_thread(struct pktgen_thread *t)
 {
         /* Remove from the thread list */
 
-        struct pktgen_thread *tmp = pktgen_threads;
-
         remove_proc_entry(t->name, pg_proc_dir);
 
         thread_lock();
 
-        if (tmp == t)
-                pktgen_threads = tmp->next;
-        else {
-                while (tmp) {
-                        if (tmp->next == t) {
-                                tmp->next = t->next;
-                                t->next = NULL;
-                                break;
-                        }
-                        tmp = tmp->next;
-                }
-        }
+        list_del(&t->th_list);
+
         thread_unlock();
 }
 
@@ -2969,6 +2952,8 @@ static void pktgen_thread_worker(struct pktgen_thread *t)
 
         PG_DEBUG(printk("pktgen: %s removing thread.\n", t->name));
         pktgen_rem_thread(t);
+
+        t->removed = 1;
 }
 
 static struct pktgen_dev *pktgen_find_dev(struct pktgen_thread *t,
@@ -3081,19 +3066,18 @@ static int pktgen_add_device(struct pktgen_thread *t, const char *ifname)
 
 static struct pktgen_thread *__init pktgen_find_thread(const char *name)
 {
-        struct pktgen_thread *t = NULL;
+        struct pktgen_thread *t;
 
         thread_lock();
 
-        t = pktgen_threads;
-        while (t) {
-                if (strcmp(t->name, name) == 0)
-                        break;
+        list_for_each_entry(t, &pktgen_threads, th_list)
+                if (strcmp(t->name, name) == 0) {
+                        thread_unlock();
+                        return t;
+                }
 
-                t = t->next;
-        }
         thread_unlock();
-        return t;
+        return NULL;
 }
 
 static int __init pktgen_create_thread(const char *name, int cpu)
@@ -3132,8 +3116,9 @@ static int __init pktgen_create_thread(const char *name, int cpu)
         pe->proc_fops = &pktgen_thread_fops;
         pe->data = t;
 
-        t->next = pktgen_threads;
-        pktgen_threads = t;
+        list_add_tail(&t->th_list, &pktgen_threads);
+
+        t->removed = 0;
 
         if (kernel_thread((void *)pktgen_thread_worker, (void *)t,
                           CLONE_FS | CLONE_FILES | CLONE_SIGHAND) < 0)
@@ -3234,17 +3219,18 @@ static int __init pg_init(void)
 
 static void __exit pg_cleanup(void)
 {
+        struct pktgen_thread *t;
+        struct list_head *q, *n;
         wait_queue_head_t queue;
         init_waitqueue_head(&queue);
 
         /* Stop all interfaces & threads */
 
-        while (pktgen_threads) {
-                struct pktgen_thread *t = pktgen_threads;
-                pktgen_threads->control |= (T_TERMINATE);
+        list_for_each_safe(q, n, &pktgen_threads) {
+                t = list_entry(q, struct pktgen_thread, th_list);
+                t->control |= (T_TERMINATE);
 
-                wait_event_interruptible_timeout(queue, (t != pktgen_threads),
-                                                 HZ);
+                wait_event_interruptible_timeout(queue, (t->removed == 1), HZ);
         }
 
         /* Un-register us from receiving netdevice events */