[PATCH 02/14] fcoe: Use percpu kernel funcs for struct fcoe_percpu_s

Robert Love
2009-03-17T18:41:51Z

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>
---

drivers/scsi/fcoe/libfcoe.c | 94 ++++++++++++++++++++-----------------------
include/scsi/libfcoe.h | 1
2 files changed, 43 insertions(+), 52 deletions(-)

diff --git a/drivers/scsi/fcoe/libfcoe.c b/drivers/scsi/fcoe/libfcoe.c
index 3865d93..d22275b 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 124dc5b..1ad4f93 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;