crypto: talitos - align locks on cache lines
authorKim Phillips <kim.phillips@freescale.com>
Thu, 13 Aug 2009 01:50:38 +0000 (11:50 +1000)
committerHerbert Xu <herbert@gondor.apana.org.au>
Thu, 13 Aug 2009 01:50:38 +0000 (11:50 +1000)
align channel access locks onto separate cache lines (for performance
reasons).  This is done by placing per-channel variables into their own
private struct, and using the cacheline_aligned attribute within that
struct.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
drivers/crypto/talitos.c

index b1a651c61829a757effc6988b81f0eca94dff2d0..5013a2dd47ed767753a8255db99d334a9d81aed3 100644 (file)
@@ -86,6 +86,25 @@ struct talitos_request {
        void *context;
 };
 
+/* per-channel fifo management */
+struct talitos_channel {
+       /* request fifo */
+       struct talitos_request *fifo;
+
+       /* number of requests pending in channel h/w fifo */
+       atomic_t submit_count ____cacheline_aligned;
+
+       /* request submission (head) lock */
+       spinlock_t head_lock ____cacheline_aligned;
+       /* index to next free descriptor request */
+       int head;
+
+       /* request release (tail) lock */
+       spinlock_t tail_lock ____cacheline_aligned;
+       /* index to next in-progress/done descriptor request */
+       int tail;
+};
+
 struct talitos_private {
        struct device *dev;
        struct of_device *ofdev;
@@ -101,15 +120,6 @@ struct talitos_private {
        /* SEC Compatibility info */
        unsigned long features;
 
-       /* next channel to be assigned next incoming descriptor */
-       atomic_t last_chan;
-
-       /* per-channel number of requests pending in channel h/w fifo */
-       atomic_t *submit_count;
-
-       /* per-channel request fifo */
-       struct talitos_request **fifo;
-
        /*
         * length of the request fifo
         * fifo_len is chfifo_len rounded up to next power of 2
@@ -117,15 +127,10 @@ struct talitos_private {
         */
        unsigned int fifo_len;
 
-       /* per-channel index to next free descriptor request */
-       int *head;
-
-       /* per-channel index to next in-progress/done descriptor request */
-       int *tail;
+       struct talitos_channel *chan;
 
-       /* per-channel request submission (head) and release (tail) locks */
-       spinlock_t *head_lock;
-       spinlock_t *tail_lock;
+       /* next channel to be assigned next incoming descriptor */
+       atomic_t last_chan ____cacheline_aligned;
 
        /* request callback tasklet */
        struct tasklet_struct done_task;
@@ -282,16 +287,16 @@ static int talitos_submit(struct device *dev, struct talitos_desc *desc,
        /* emulate SEC's round-robin channel fifo polling scheme */
        ch = atomic_inc_return(&priv->last_chan) & (priv->num_channels - 1);
 
-       spin_lock_irqsave(&priv->head_lock[ch], flags);
+       spin_lock_irqsave(&priv->chan[ch].head_lock, flags);
 
-       if (!atomic_inc_not_zero(&priv->submit_count[ch])) {
+       if (!atomic_inc_not_zero(&priv->chan[ch].submit_count)) {
                /* h/w fifo is full */
-               spin_unlock_irqrestore(&priv->head_lock[ch], flags);
+               spin_unlock_irqrestore(&priv->chan[ch].head_lock, flags);
                return -EAGAIN;
        }
 
-       head = priv->head[ch];
-       request = &priv->fifo[ch][head];
+       head = priv->chan[ch].head;
+       request = &priv->chan[ch].fifo[head];
 
        /* map descriptor and save caller data */
        request->dma_desc = dma_map_single(dev, desc, sizeof(*desc),
@@ -300,7 +305,7 @@ static int talitos_submit(struct device *dev, struct talitos_desc *desc,
        request->context = context;
 
        /* increment fifo head */
-       priv->head[ch] = (priv->head[ch] + 1) & (priv->fifo_len - 1);
+       priv->chan[ch].head = (priv->chan[ch].head + 1) & (priv->fifo_len - 1);
 
        smp_wmb();
        request->desc = desc;
@@ -309,7 +314,7 @@ static int talitos_submit(struct device *dev, struct talitos_desc *desc,
        wmb();
        out_be32(priv->reg + TALITOS_FF_LO(ch), request->dma_desc);
 
-       spin_unlock_irqrestore(&priv->head_lock[ch], flags);
+       spin_unlock_irqrestore(&priv->chan[ch].head_lock, flags);
 
        return -EINPROGRESS;
 }
@@ -324,11 +329,11 @@ static void flush_channel(struct device *dev, int ch, int error, int reset_ch)
        unsigned long flags;
        int tail, status;
 
-       spin_lock_irqsave(&priv->tail_lock[ch], flags);
+       spin_lock_irqsave(&priv->chan[ch].tail_lock, flags);
 
-       tail = priv->tail[ch];
-       while (priv->fifo[ch][tail].desc) {
-               request = &priv->fifo[ch][tail];
+       tail = priv->chan[ch].tail;
+       while (priv->chan[ch].fifo[tail].desc) {
+               request = &priv->chan[ch].fifo[tail];
 
                /* descriptors with their done bits set don't get the error */
                rmb();
@@ -354,22 +359,22 @@ static void flush_channel(struct device *dev, int ch, int error, int reset_ch)
                request->desc = NULL;
 
                /* increment fifo tail */
-               priv->tail[ch] = (tail + 1) & (priv->fifo_len - 1);
+               priv->chan[ch].tail = (tail + 1) & (priv->fifo_len - 1);
 
-               spin_unlock_irqrestore(&priv->tail_lock[ch], flags);
+               spin_unlock_irqrestore(&priv->chan[ch].tail_lock, flags);
 
-               atomic_dec(&priv->submit_count[ch]);
+               atomic_dec(&priv->chan[ch].submit_count);
 
                saved_req.callback(dev, saved_req.desc, saved_req.context,
                                   status);
                /* channel may resume processing in single desc error case */
                if (error && !reset_ch && status == error)
                        return;
-               spin_lock_irqsave(&priv->tail_lock[ch], flags);
-               tail = priv->tail[ch];
+               spin_lock_irqsave(&priv->chan[ch].tail_lock, flags);
+               tail = priv->chan[ch].tail;
        }
 
-       spin_unlock_irqrestore(&priv->tail_lock[ch], flags);
+       spin_unlock_irqrestore(&priv->chan[ch].tail_lock, flags);
 }
 
 /*
@@ -397,20 +402,20 @@ static void talitos_done(unsigned long data)
 static struct talitos_desc *current_desc(struct device *dev, int ch)
 {
        struct talitos_private *priv = dev_get_drvdata(dev);
-       int tail = priv->tail[ch];
+       int tail = priv->chan[ch].tail;
        dma_addr_t cur_desc;
 
        cur_desc = in_be32(priv->reg + TALITOS_CDPR_LO(ch));
 
-       while (priv->fifo[ch][tail].dma_desc != cur_desc) {
+       while (priv->chan[ch].fifo[tail].dma_desc != cur_desc) {
                tail = (tail + 1) & (priv->fifo_len - 1);
-               if (tail == priv->tail[ch]) {
+               if (tail == priv->chan[ch].tail) {
                        dev_err(dev, "couldn't locate current descriptor\n");
                        return NULL;
                }
        }
 
-       return priv->fifo[ch][tail].desc;
+       return priv->chan[ch].fifo[tail].desc;
 }
 
 /*
@@ -1740,17 +1745,11 @@ static int talitos_remove(struct of_device *ofdev)
        if (hw_supports(dev, DESC_HDR_SEL0_RNG))
                talitos_unregister_rng(dev);
 
-       kfree(priv->submit_count);
-       kfree(priv->tail);
-       kfree(priv->head);
-
-       if (priv->fifo)
-               for (i = 0; i < priv->num_channels; i++)
-                       kfree(priv->fifo[i]);
+       for (i = 0; i < priv->num_channels; i++)
+               if (priv->chan[i].fifo)
+                       kfree(priv->chan[i].fifo);
 
-       kfree(priv->fifo);
-       kfree(priv->head_lock);
-       kfree(priv->tail_lock);
+       kfree(priv->chan);
 
        if (priv->irq != NO_IRQ) {
                free_irq(priv->irq, dev);
@@ -1870,58 +1869,34 @@ static int talitos_probe(struct of_device *ofdev,
        if (of_device_is_compatible(np, "fsl,sec2.1"))
                priv->features |= TALITOS_FTR_HW_AUTH_CHECK;
 
-       priv->head_lock = kmalloc(sizeof(spinlock_t) * priv->num_channels,
-                                 GFP_KERNEL);
-       priv->tail_lock = kmalloc(sizeof(spinlock_t) * priv->num_channels,
-                                 GFP_KERNEL);
-       if (!priv->head_lock || !priv->tail_lock) {
-               dev_err(dev, "failed to allocate fifo locks\n");
+       priv->chan = kzalloc(sizeof(struct talitos_channel) *
+                            priv->num_channels, GFP_KERNEL);
+       if (!priv->chan) {
+               dev_err(dev, "failed to allocate channel management space\n");
                err = -ENOMEM;
                goto err_out;
        }
 
        for (i = 0; i < priv->num_channels; i++) {
-               spin_lock_init(&priv->head_lock[i]);
-               spin_lock_init(&priv->tail_lock[i]);
-       }
-
-       priv->fifo = kmalloc(sizeof(struct talitos_request *) *
-                            priv->num_channels, GFP_KERNEL);
-       if (!priv->fifo) {
-               dev_err(dev, "failed to allocate request fifo\n");
-               err = -ENOMEM;
-               goto err_out;
+               spin_lock_init(&priv->chan[i].head_lock);
+               spin_lock_init(&priv->chan[i].tail_lock);
        }
 
        priv->fifo_len = roundup_pow_of_two(priv->chfifo_len);
 
        for (i = 0; i < priv->num_channels; i++) {
-               priv->fifo[i] = kzalloc(sizeof(struct talitos_request) *
-                                       priv->fifo_len, GFP_KERNEL);
-               if (!priv->fifo[i]) {
+               priv->chan[i].fifo = kzalloc(sizeof(struct talitos_request) *
+                                            priv->fifo_len, GFP_KERNEL);
+               if (!priv->chan[i].fifo) {
                        dev_err(dev, "failed to allocate request fifo %d\n", i);
                        err = -ENOMEM;
                        goto err_out;
                }
        }
 
-       priv->submit_count = kmalloc(sizeof(atomic_t) * priv->num_channels,
-                                    GFP_KERNEL);
-       if (!priv->submit_count) {
-               dev_err(dev, "failed to allocate fifo submit count space\n");
-               err = -ENOMEM;
-               goto err_out;
-       }
        for (i = 0; i < priv->num_channels; i++)
-               atomic_set(&priv->submit_count[i], -(priv->chfifo_len - 1));
-
-       priv->head = kzalloc(sizeof(int) * priv->num_channels, GFP_KERNEL);
-       priv->tail = kzalloc(sizeof(int) * priv->num_channels, GFP_KERNEL);
-       if (!priv->head || !priv->tail) {
-               dev_err(dev, "failed to allocate request index space\n");
-               err = -ENOMEM;
-               goto err_out;
-       }
+               atomic_set(&priv->chan[i].submit_count,
+                          -(priv->chfifo_len - 1));
 
        /* reset and initialize the h/w */
        err = init_device(dev);