[SCSI] fcoe: Use per-CPU kernel function for dev_stats instead of an array

Remove the hotplug creation of dev_stats, we allocate for all possible CPUs
now when we allocate the lport.

v2: Durring the 2.6.30 merge window, before these patches were comitted,
'percpu_ptr' was renamed 'per_cpu_ptr'. This latest update updates this
patch for the name change.

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>

diff --git a/drivers/scsi/fcoe/fcoe_sw.c b/drivers/scsi/fcoe/fcoe_sw.c
index 2bbbe3c..a675390 100644 (file)
--- a/drivers/scsi/fcoe/fcoe_sw.c
+++ b/drivers/scsi/fcoe/fcoe_sw.c
@@ -113,8 +113,6 @@ static struct scsi_host_template fcoe_sw_shost_template = {
  */
 static int fcoe_sw_lport_config(struct fc_lport *lp)
 {
-       int i = 0;
-
        lp->link_up = 0;
        lp->qfull = 0;
        lp->max_retry_count = 3;
@@ -123,12 +121,7 @@ static int fcoe_sw_lport_config(struct fc_lport *lp)
        lp->service_params = (FCP_SPPF_INIT_FCN | FCP_SPPF_RD_XRDY_DIS |
                              FCP_SPPF_RETRY | FCP_SPPF_CONF_COMPL);
 
-       /*
-        * allocate per cpu stats block
-        */
-       for_each_online_cpu(i)
-               lp->dev_stats[i] = kzalloc(sizeof(struct fcoe_dev_stats),
-                                          GFP_KERNEL);
+       fc_lport_init_stats(lp);
 
        /* lport fc_lport related configuration */
        fc_lport_config(lp);
@@ -311,7 +304,6 @@ static inline int fcoe_sw_em_config(struct fc_lport *lp)
  */
 static int fcoe_sw_destroy(struct net_device *netdev)
 {
-       int cpu;
        struct fc_lport *lp = NULL;
        struct fcoe_softc *fc;
        u8 flogi_maddr[ETH_ALEN];
@@ -363,8 +355,7 @@ static int fcoe_sw_destroy(struct net_device *netdev)
        fcoe_clean_pending_queue(lp);
 
        /* Free memory used by statistical counters */
-       for_each_online_cpu(cpu)
-               kfree(lp->dev_stats[cpu]);
+       fc_lport_free_stats(lp);
 
        /* Release the net_device and Scsi_Host */
        dev_put(fc->real_dev);

diff --git a/drivers/scsi/fcoe/libfcoe.c b/drivers/scsi/fcoe/libfcoe.c
index d22275b..648a2fc 100644 (file)
--- a/drivers/scsi/fcoe/libfcoe.c
+++ b/drivers/scsi/fcoe/libfcoe.c
@@ -71,9 +71,6 @@ DEFINE_PER_CPU(struct fcoe_percpu_s, fcoe_percpu);
 /* Function Prototyes */
 static int fcoe_check_wait_queue(struct fc_lport *);
 static void fcoe_recv_flogi(struct fcoe_softc *, struct fc_frame *, u8 *);
-#ifdef CONFIG_HOTPLUG_CPU
-static int fcoe_cpu_callback(struct notifier_block *, ulong, void *);
-#endif /* CONFIG_HOTPLUG_CPU */
 static int fcoe_device_notification(struct notifier_block *, ulong, void *);
 static void fcoe_dev_setup(void);
 static void fcoe_dev_cleanup(void);
@@ -83,87 +80,6 @@ static struct notifier_block fcoe_notifier = {
        .notifier_call = fcoe_device_notification,
 };
 
-
-#ifdef CONFIG_HOTPLUG_CPU
-static struct notifier_block fcoe_cpu_notifier = {
-       .notifier_call = fcoe_cpu_callback,
-};
-
-/**
- * fcoe_create_percpu_data() - creates the associated cpu data
- * @cpu: index for the cpu where fcoe cpu data will be created
- *
- * create percpu stats block, from cpu add notifier
- *
- * Returns: none
- */
-static void fcoe_create_percpu_data(unsigned int cpu)
-{
-       struct fc_lport *lp;
-       struct fcoe_softc *fc;
-
-       write_lock_bh(&fcoe_hostlist_lock);
-       list_for_each_entry(fc, &fcoe_hostlist, list) {
-               lp = fc->lp;
-               if (lp->dev_stats[cpu] == NULL)
-                       lp->dev_stats[cpu] =
-                               kzalloc(sizeof(struct fcoe_dev_stats),
-                                       GFP_KERNEL);
-       }
-       write_unlock_bh(&fcoe_hostlist_lock);
-}
-
-/**
- * fcoe_destroy_percpu_data() - destroys the associated cpu data
- * @cpu: index for the cpu where fcoe cpu data will destroyed
- *
- * destroy percpu stats block called by cpu add/remove notifier
- *
- * Retuns: none
- */
-static void fcoe_destroy_percpu_data(unsigned int cpu)
-{
-       struct fc_lport *lp;
-       struct fcoe_softc *fc;
-
-       write_lock_bh(&fcoe_hostlist_lock);
-       list_for_each_entry(fc, &fcoe_hostlist, list) {
-               lp = fc->lp;
-               kfree(lp->dev_stats[cpu]);
-               lp->dev_stats[cpu] = NULL;
-       }
-       write_unlock_bh(&fcoe_hostlist_lock);
-}
-
-/**
- * fcoe_cpu_callback() - fcoe cpu hotplug event callback
- * @nfb: callback data block
- * @action: event triggering the callback
- * @hcpu: index for the cpu of this event
- *
- * this creates or destroys per cpu data for fcoe
- *
- * Returns NOTIFY_OK always.
- */
-static int fcoe_cpu_callback(struct notifier_block *nfb, unsigned long action,
-                            void *hcpu)
-{
-       unsigned int cpu = (unsigned long)hcpu;
-
-       switch (action) {
-       case CPU_ONLINE:
-               fcoe_create_percpu_data(cpu);
-               break;
-       case CPU_DEAD:
-               fcoe_destroy_percpu_data(cpu);
-               break;
-       default:
-               break;
-       }
-       return NOTIFY_OK;
-}
-#endif /* CONFIG_HOTPLUG_CPU */
-
 /**
  * fcoe_rcv() - this is the fcoe receive function called by NET_RX_SOFTIRQ
  * @skb: the receive skb
@@ -181,7 +97,6 @@ int fcoe_rcv(struct sk_buff *skb, struct net_device *dev,
        struct fc_lport *lp;
        struct fcoe_rcv_info *fr;
        struct fcoe_softc *fc;
-       struct fcoe_dev_stats *stats;
        struct fc_frame_header *fh;
        struct fcoe_percpu_s *fps;
        unsigned short oxid;
@@ -252,13 +167,7 @@ int fcoe_rcv(struct sk_buff *skb, struct net_device *dev,
 
        return 0;
 err:
-#ifdef CONFIG_SMP
-       stats = lp->dev_stats[smp_processor_id()];
-#else
-       stats = lp->dev_stats[0];
-#endif
-       if (stats)
-               stats->ErrorFrames++;
+       fc_lport_get_stats(lp)->ErrorFrames++;
 
 err2:
        kfree_skb(skb);
@@ -495,11 +404,9 @@ int fcoe_xmit(struct fc_lport *lp, struct fc_frame *fp)
        }
 #endif
        /* update tx stats: regardless if LLD fails */
-       stats = lp->dev_stats[smp_processor_id()];
-       if (stats) {
-               stats->TxFrames++;
-               stats->TxWords += wlen;
-       }
+       stats = fc_lport_get_stats(lp);
+       stats->TxFrames++;
+       stats->TxWords += wlen;
 
        /* send down to lld */
        fr_dev(fp) = lp;
@@ -565,8 +472,6 @@ int fcoe_percpu_receive_thread(void *arg)
                        continue;
                }
 
-               stats = lp->dev_stats[smp_processor_id()];
-
                if (unlikely(debug_fcoe)) {
                        FC_DBG("skb_info: len:%d data_len:%d head:%p data:%p "
                               "tail:%p end:%p sum:%d dev:%s",
@@ -593,13 +498,16 @@ int fcoe_percpu_receive_thread(void *arg)
                hp = (struct fcoe_hdr *) skb_network_header(skb);
                fh = (struct fc_frame_header *) skb_transport_header(skb);
 
+               stats = fc_lport_get_stats(lp);
                if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) {
-                       if (stats) {
-                               if (stats->ErrorFrames < 5)
-                                       FC_DBG("unknown FCoE version %x",
-                                              FC_FCOE_DECAPS_VER(hp));
-                               stats->ErrorFrames++;
-                       }
+                       if (stats->ErrorFrames < 5)
+                               printk(KERN_WARNING "FCoE version "
+                                      "mismatch: The frame has "
+                                      "version %x, but the "
+                                      "initiator supports version "
+                                      "%x\n", FC_FCOE_DECAPS_VER(hp),
+                                      FC_FCOE_VER);
+                       stats->ErrorFrames++;
                        kfree_skb(skb);
                        continue;
                }
@@ -607,10 +515,8 @@ int fcoe_percpu_receive_thread(void *arg)
                skb_pull(skb, sizeof(struct fcoe_hdr));
                fr_len = skb->len - sizeof(struct fcoe_crc_eof);
 
-               if (stats) {
-                       stats->RxFrames++;
-                       stats->RxWords += fr_len / FCOE_WORD_TO_BYTE;
-               }
+               stats->RxFrames++;
+               stats->RxWords += fr_len / FCOE_WORD_TO_BYTE;
 
                fp = (struct fc_frame *)skb;
                fc_frame_init(fp);
@@ -885,9 +791,8 @@ static int fcoe_device_notification(struct notifier_block *notifier,
                if (new_link_up)
                        fc_linkup(lp);
                else {
-                       stats = lp->dev_stats[smp_processor_id()];
-                       if (stats)
-                               stats->LinkFailureCount++;
+                       stats = fc_lport_get_stats(lp);
+                       stats->LinkFailureCount++;
                        fc_linkdown(lp);
                        fcoe_clean_pending_queue(lp);
                }
@@ -1371,10 +1276,6 @@ static int __init fcoe_init(void)
        INIT_LIST_HEAD(&fcoe_hostlist);
        rwlock_init(&fcoe_hostlist_lock);
 
-#ifdef CONFIG_HOTPLUG_CPU
-       register_cpu_notifier(&fcoe_cpu_notifier);
-#endif /* CONFIG_HOTPLUG_CPU */
-
        for_each_possible_cpu(cpu) {
                p = &per_cpu(fcoe_percpu, cpu);
                skb_queue_head_init(&p->fcoe_rx_list);
@@ -1430,17 +1331,9 @@ static void __exit fcoe_exit(void)
        struct fcoe_percpu_s *p;
        struct sk_buff *skb;
 
-       /*
-        * Stop all call back interfaces
-        */
-#ifdef CONFIG_HOTPLUG_CPU
-       unregister_cpu_notifier(&fcoe_cpu_notifier);
-#endif /* CONFIG_HOTPLUG_CPU */
        fcoe_dev_cleanup();
 
-       /*
-        * stop timer
-        */
+       /* Stop the timer */
        del_timer_sync(&fcoe_timer);
 
        /* releases the associated fcoe transport for each lport */

diff --git a/drivers/scsi/libfc/fc_fcp.c b/drivers/scsi/libfc/fc_fcp.c
index a5725f3..0997e8b 100644 (file)
--- a/drivers/scsi/libfc/fc_fcp.c
+++ b/drivers/scsi/libfc/fc_fcp.c
@@ -407,10 +407,12 @@ static void fc_fcp_recv_data(struct fc_fcp_pkt *fsp, struct fc_frame *fp)
 
                if (~crc != le32_to_cpu(fr_crc(fp))) {
 crc_err:
-                       stats = lp->dev_stats[smp_processor_id()];
+                       stats = fc_lport_get_stats(lp);
                        stats->ErrorFrames++;
+                       /* FIXME - per cpu count, not total count! */
                        if (stats->InvalidCRCCount++ < 5)
-                               FC_DBG("CRC error on data frame\n");
+                               printk(KERN_WARNING "CRC error on data frame for port (%6x)\n",
+                                      fc_host_port_id(lp->host));
                        /*
                         * Assume the frame is total garbage.
                         * We may have copied it over the good part
@@ -1752,7 +1754,7 @@ int fc_queuecommand(struct scsi_cmnd *sc_cmd, void (*done)(struct scsi_cmnd *))
        /*
         * setup the data direction
         */
-       stats = lp->dev_stats[smp_processor_id()];
+       stats = fc_lport_get_stats(lp);
        if (sc_cmd->sc_data_direction == DMA_FROM_DEVICE) {
                fsp->req_flags = FC_SRB_READ;
                stats->InputRequests++;

diff --git a/drivers/scsi/libfc/fc_lport.c b/drivers/scsi/libfc/fc_lport.c
index 7ef4450..b8178ef 100644 (file)
--- a/drivers/scsi/libfc/fc_lport.c
+++ b/drivers/scsi/libfc/fc_lport.c
@@ -267,10 +267,10 @@ EXPORT_SYMBOL(fc_get_host_speed);
 
 struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost)
 {
-       int i;
        struct fc_host_statistics *fcoe_stats;
        struct fc_lport *lp = shost_priv(shost);
        struct timespec v0, v1;
+       unsigned int cpu;
 
        fcoe_stats = &lp->host_stats;
        memset(fcoe_stats, 0, sizeof(struct fc_host_statistics));
@@ -279,10 +279,11 @@ struct fc_host_statistics *fc_get_host_stats(struct Scsi_Host *shost)
        jiffies_to_timespec(lp->boot_time, &v1);
        fcoe_stats->seconds_since_last_reset = (v0.tv_sec - v1.tv_sec);
 
-       for_each_online_cpu(i) {
-               struct fcoe_dev_stats *stats = lp->dev_stats[i];
-               if (stats == NULL)
-                       continue;
+       for_each_possible_cpu(cpu) {
+               struct fcoe_dev_stats *stats;
+
+               stats = per_cpu_ptr(lp->dev_stats, cpu);
+
                fcoe_stats->tx_frames += stats->TxFrames;
                fcoe_stats->tx_words += stats->TxWords;
                fcoe_stats->rx_frames += stats->RxFrames;

diff --git a/include/scsi/libfc.h b/include/scsi/libfc.h
index a70eafa..4e1d394 100644 (file)
--- a/include/scsi/libfc.h
+++ b/include/scsi/libfc.h
@@ -22,6 +22,7 @@
 
 #include <linux/timer.h>
 #include <linux/if.h>
+#include <linux/percpu.h>
 
 #include <scsi/scsi_transport.h>
 #include <scsi/scsi_transport_fc.h>
@@ -661,7 +662,8 @@ struct fc_lport {
        unsigned long           boot_time;
 
        struct fc_host_statistics host_stats;
-       struct fcoe_dev_stats   *dev_stats[NR_CPUS];
+       struct fcoe_dev_stats   *dev_stats;
+
        u64                     wwpn;
        u64                     wwnn;
        u8                      retry_count;
@@ -722,6 +724,25 @@ static inline void fc_lport_state_enter(struct fc_lport *lp,
        lp->state = state;
 }
 
+static inline int fc_lport_init_stats(struct fc_lport *lp)
+{
+       /* allocate per cpu stats block */
+       lp->dev_stats = alloc_percpu(struct fcoe_dev_stats);
+       if (!lp->dev_stats)
+               return -ENOMEM;
+       return 0;
+}
+
+static inline void fc_lport_free_stats(struct fc_lport *lp)
+{
+       free_percpu(lp->dev_stats);
+}
+
+static inline struct fcoe_dev_stats *fc_lport_get_stats(struct fc_lport *lp)
+{
+       return per_cpu_ptr(lp->dev_stats, smp_processor_id());
+}
+
 
 /*
  * LOCAL PORT LAYER