[SCSI] fcoe: Use percpu kernel funcs for struct fcoe_percpu_s

Convert fcoe_percpu array to use the per-cpu variables
that the kernel provides. Use the kernel's functions to
access this structure.

The cpu member of the fcoe_percpu_s is no longer needed,
so this patch removes it too.

Signed-off-by: Yi Zou <yi.zou@intel.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

2 files changed, 43 insertions, 52 deletions

diff --git a/drivers/scsi/fcoe/libfcoe.c b/drivers/scsi/fcoe/libfcoe.c
index 3865d936dee8..d22275bf57f8 100644
--- a/drivers/scsi/fcoe/libfcoe.c
+++ b/drivers/scsi/fcoe/libfcoe.c
@@ -65,7 +65,7 @@ MODULE_LICENSE("GPL");
 LIST_HEAD(fcoe_hostlist);
 DEFINE_RWLOCK(fcoe_hostlist_lock);
 DEFINE_TIMER(fcoe_timer, NULL, 0, 0);
-struct fcoe_percpu_s *fcoe_percpu[NR_CPUS];
+DEFINE_PER_CPU(struct fcoe_percpu_s, fcoe_percpu);
 
 
 /* Function Prototyes */
@@ -226,6 +226,7 @@ int fcoe_rcv(struct sk_buff *skb, struct net_device *dev,
         fr->fr_dev = lp;
         fr->ptype = ptype;
         cpu_idx = 0;
+
 #ifdef CONFIG_SMP
         /*
          * The incoming frame exchange id(oxid) is ANDed with num of online
@@ -235,10 +236,12 @@ int fcoe_rcv(struct sk_buff *skb, struct net_device *dev,
          * initialize to first online cpu index.
          */
         cpu_idx = oxid & (num_online_cpus() - 1);
-        if (!fcoe_percpu[cpu_idx] || !cpu_online(cpu_idx))
+        if (!cpu_online(cpu_idx))
                 cpu_idx = first_cpu(cpu_online_map);
+
 #endif
-        fps = fcoe_percpu[cpu_idx];
+
+        fps = &per_cpu(fcoe_percpu, cpu_idx);
 
         spin_lock_bh(&fps->fcoe_rx_list.lock);
         __skb_queue_tail(&fps->fcoe_rx_list, skb);
@@ -292,15 +295,13 @@ static int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen)
 {
         struct fcoe_percpu_s *fps;
         struct page *page;
-        unsigned int cpu_idx;
 
-        cpu_idx = get_cpu();
-        fps = fcoe_percpu[cpu_idx];
+        fps = &get_cpu_var(fcoe_percpu);
         page = fps->crc_eof_page;
         if (!page) {
                 page = alloc_page(GFP_ATOMIC);
                 if (!page) {
-                        put_cpu();
+                        put_cpu_var(fcoe_percpu);
                         return -ENOMEM;
                 }
                 fps->crc_eof_page = page;
@@ -320,7 +321,7 @@ static int fcoe_get_paged_crc_eof(struct sk_buff *skb, int tlen)
                 fps->crc_eof_offset = 0;
                 put_page(page);
         }
-        put_cpu();
+        put_cpu_var(fcoe_percpu);
         return 0;
 }
 
@@ -1122,30 +1123,28 @@ EXPORT_SYMBOL_GPL(fcoe_link_ok);
  */
 void fcoe_percpu_clean(struct fc_lport *lp)
 {
-        int idx;
         struct fcoe_percpu_s *pp;
         struct fcoe_rcv_info *fr;
         struct sk_buff_head *list;
         struct sk_buff *skb, *next;
         struct sk_buff *head;
+        unsigned int cpu;
 
-        for (idx = 0; idx < NR_CPUS; idx++) {
-                if (fcoe_percpu[idx]) {
-                        pp = fcoe_percpu[idx];
-                        spin_lock_bh(&pp->fcoe_rx_list.lock);
-                        list = &pp->fcoe_rx_list;
-                        head = list->next;
-                        for (skb = head; skb != (struct sk_buff *)list;
-                             skb = next) {
-                                next = skb->next;
-                                fr = fcoe_dev_from_skb(skb);
-                                if (fr->fr_dev == lp) {
-                                        __skb_unlink(skb, list);
-                                        kfree_skb(skb);
-                                }
+        for_each_possible_cpu(cpu) {
+                pp = &per_cpu(fcoe_percpu, cpu);
+                spin_lock_bh(&pp->fcoe_rx_list.lock);
+                list = &pp->fcoe_rx_list;
+                head = list->next;
+                for (skb = head; skb != (struct sk_buff *)list;
+                     skb = next) {
+                        next = skb->next;
+                        fr = fcoe_dev_from_skb(skb);
+                        if (fr->fr_dev == lp) {
+                                __skb_unlink(skb, list);
+                                kfree_skb(skb);
                         }
-                        spin_unlock_bh(&pp->fcoe_rx_list.lock);
                 }
+                spin_unlock_bh(&pp->fcoe_rx_list.lock);
         }
 }
 EXPORT_SYMBOL_GPL(fcoe_percpu_clean);
@@ -1377,8 +1376,7 @@ static int __init fcoe_init(void)
 #endif /* CONFIG_HOTPLUG_CPU */
 
         for_each_possible_cpu(cpu) {
-                p = fcoe_percpu[cpu];
-                p->cpu = cpu;
+                p = &per_cpu(fcoe_percpu, cpu);
                 skb_queue_head_init(&p->fcoe_rx_list);
         }
 
@@ -1386,24 +1384,19 @@ static int __init fcoe_init(void)
          * initialize per CPU interrupt thread
          */
         for_each_online_cpu(cpu) {
-                p = kzalloc(sizeof(struct fcoe_percpu_s), GFP_KERNEL);
-                if (p) {
-                        p->thread = kthread_create(fcoe_percpu_receive_thread,
-                                                   (void *)p,
-                                                   "fcoethread/%d", cpu);
+                p = &per_cpu(fcoe_percpu, cpu);
+                p->thread = kthread_create(fcoe_percpu_receive_thread,
+                                           (void *)p, "fcoethread/%d", cpu);
 
-                        /*
-                         * if there is no error then bind the thread to the cpu
-                         * initialize the semaphore and skb queue head
-                         */
-                        if (likely(!IS_ERR(p->thread))) {
-                                fcoe_percpu[cpu] = p;
-                                kthread_bind(p->thread, cpu);
-                                wake_up_process(p->thread);
-                        } else {
-                                fcoe_percpu[cpu] = NULL;
-                                kfree(p);
-                        }
+                /*
+                 * If there is no error then bind the thread to the CPU
+                 * and wake it up.
+                 */
+                if (!IS_ERR(p->thread)) {
+                        kthread_bind(p->thread, cpu);
+                        wake_up_process(p->thread);
+                } else {
+                        p->thread = NULL;
                 }
         }
 
@@ -1432,7 +1425,7 @@ module_init(fcoe_init);
  */
 static void __exit fcoe_exit(void)
 {
-        u32 idx;
+        unsigned int cpu;
         struct fcoe_softc *fc, *tmp;
         struct fcoe_percpu_s *p;
         struct sk_buff *skb;
@@ -1454,17 +1447,16 @@ static void __exit fcoe_exit(void)
         list_for_each_entry_safe(fc, tmp, &fcoe_hostlist, list)
                 fcoe_transport_release(fc->real_dev);
 
-        for (idx = 0; idx < NR_CPUS; idx++) {
-                if (fcoe_percpu[idx]) {
-                        kthread_stop(fcoe_percpu[idx]->thread);
-                        p = fcoe_percpu[idx];
+        for_each_possible_cpu(cpu) {
+                p = &per_cpu(fcoe_percpu, cpu);
+                if (p->thread) {
+                        kthread_stop(p->thread);
                         spin_lock_bh(&p->fcoe_rx_list.lock);
                         while ((skb = __skb_dequeue(&p->fcoe_rx_list)) != NULL)
                                 kfree_skb(skb);
                         spin_unlock_bh(&p->fcoe_rx_list.lock);
-                        if (fcoe_percpu[idx]->crc_eof_page)
-                                put_page(fcoe_percpu[idx]->crc_eof_page);
-                        kfree(fcoe_percpu[idx]);
+                        if (p->crc_eof_page)
+                                put_page(p->crc_eof_page);
                 }
         }
 
diff --git a/include/scsi/libfcoe.h b/include/scsi/libfcoe.h
index 124dc5bd9f87..1ad4f93d5548 100644
--- a/include/scsi/libfcoe.h
+++ b/include/scsi/libfcoe.h
@@ -29,7 +29,6 @@
  * this percpu struct for fcoe
  */
 struct fcoe_percpu_s {
-        unsigned int cpu;
         struct task_struct *thread;
         struct sk_buff_head fcoe_rx_list;
         struct page *crc_eof_page;