ptp: Replace timestamp event queue with linked list

Introduce linked lists to access the timestamp event queue.

Signed-off-by: Xabier Marquiegui <reibax@gmail.com>
Suggested-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/ptp/ptp_chardev.c b/drivers/ptp/ptp_chardev.c
index 0ba3e7064df281ba7d462696c4ac60bdb403c0e4..aa1990d2ab46a1b43311f8f3984734a135833e2b 100644 (file)
--- a/drivers/ptp/ptp_chardev.c
+++ b/drivers/ptp/ptp_chardev.c
@@ -439,10 +439,14 @@ __poll_t ptp_poll(struct posix_clock_context *pccontext, struct file *fp,
 {
        struct ptp_clock *ptp =
                container_of(pccontext->clk, struct ptp_clock, clock);
+       struct timestamp_event_queue *queue;
 
        poll_wait(fp, &ptp->tsev_wq, wait);
 
-       return queue_cnt(&ptp->tsevq) ? EPOLLIN : 0;
+       /* Extract only the first element in the queue list */
+       queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue, qlist);
+
+       return queue_cnt(queue) ? EPOLLIN : 0;
 }
 
 #define EXTTS_BUFSIZE (PTP_BUF_TIMESTAMPS * sizeof(struct ptp_extts_event))
@@ -452,12 +456,16 @@ ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags,
 {
        struct ptp_clock *ptp =
                container_of(pccontext->clk, struct ptp_clock, clock);
-       struct timestamp_event_queue *queue = &ptp->tsevq;
+       struct timestamp_event_queue *queue;
        struct ptp_extts_event *event;
        unsigned long flags;
        size_t qcnt, i;
        int result;
 
+       /* Extract only the first element in the queue list */
+       queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
+                                qlist);
+
        if (cnt % sizeof(struct ptp_extts_event) != 0)
                return -EINVAL;
 

diff --git a/drivers/ptp/ptp_clock.c b/drivers/ptp/ptp_clock.c
index 80f74e38c2da4b5fac16a560dea2049455829fbe..157ef25bc1b10919f9523c5736df0966c45a78b3 100644 (file)
--- a/drivers/ptp/ptp_clock.c
+++ b/drivers/ptp/ptp_clock.c
@@ -169,12 +169,21 @@ static struct posix_clock_operations ptp_clock_ops = {
 static void ptp_clock_release(struct device *dev)
 {
        struct ptp_clock *ptp = container_of(dev, struct ptp_clock, dev);
+       struct timestamp_event_queue *tsevq;
+       unsigned long flags;
 
        ptp_cleanup_pin_groups(ptp);
        kfree(ptp->vclock_index);
        mutex_destroy(&ptp->tsevq_mux);
        mutex_destroy(&ptp->pincfg_mux);
        mutex_destroy(&ptp->n_vclocks_mux);
+       /* Delete first entry */
+       tsevq = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
+                                qlist);
+       spin_lock_irqsave(&tsevq->lock, flags);
+       list_del(&tsevq->qlist);
+       spin_unlock_irqrestore(&tsevq->lock, flags);
+       kfree(tsevq);
        ida_free(&ptp_clocks_map, ptp->index);
        kfree(ptp);
 }
@@ -206,6 +215,7 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
                                     struct device *parent)
 {
        struct ptp_clock *ptp;
+       struct timestamp_event_queue *queue = NULL;
        int err = 0, index, major = MAJOR(ptp_devt);
        size_t size;
 
@@ -228,7 +238,12 @@ struct ptp_clock *ptp_clock_register(struct ptp_clock_info *info,
        ptp->info = info;
        ptp->devid = MKDEV(major, index);
        ptp->index = index;
-       spin_lock_init(&ptp->tsevq.lock);
+       INIT_LIST_HEAD(&ptp->tsevqs);
+       queue = kzalloc(sizeof(*queue), GFP_KERNEL);
+       if (!queue)
+               goto no_memory_queue;
+       spin_lock_init(&queue->lock);
+       list_add_tail(&queue->qlist, &ptp->tsevqs);
        mutex_init(&ptp->tsevq_mux);
        mutex_init(&ptp->pincfg_mux);
        mutex_init(&ptp->n_vclocks_mux);
@@ -333,6 +348,9 @@ kworker_err:
        mutex_destroy(&ptp->tsevq_mux);
        mutex_destroy(&ptp->pincfg_mux);
        mutex_destroy(&ptp->n_vclocks_mux);
+       list_del(&queue->qlist);
+       kfree(queue);
+no_memory_queue:
        ida_free(&ptp_clocks_map, index);
 no_slot:
        kfree(ptp);
@@ -375,6 +393,7 @@ EXPORT_SYMBOL(ptp_clock_unregister);
 
 void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
 {
+       struct timestamp_event_queue *tsevq;
        struct pps_event_time evt;
 
        switch (event->type) {
@@ -383,7 +402,10 @@ void ptp_clock_event(struct ptp_clock *ptp, struct ptp_clock_event *event)
                break;
 
        case PTP_CLOCK_EXTTS:
-               enqueue_external_timestamp(&ptp->tsevq, event);
+               /* Enqueue timestamp on all queues */
+               list_for_each_entry(tsevq, &ptp->tsevqs, qlist) {
+                       enqueue_external_timestamp(tsevq, event);
+               }
                wake_up_interruptible(&ptp->tsev_wq);
                break;
 

diff --git a/drivers/ptp/ptp_private.h b/drivers/ptp/ptp_private.h
index a3110c85f694ff0234a12a3f13665c3f9b10fb51..cc8186a92eec65b08f2d5afc3466d79ee0f463b2 100644 (file)
--- a/drivers/ptp/ptp_private.h
+++ b/drivers/ptp/ptp_private.h
@@ -15,6 +15,7 @@
 #include <linux/ptp_clock.h>
 #include <linux/ptp_clock_kernel.h>
 #include <linux/time.h>
+#include <linux/list.h>
 
 #define PTP_MAX_TIMESTAMPS 128
 #define PTP_BUF_TIMESTAMPS 30
@@ -25,6 +26,7 @@ struct timestamp_event_queue {
        int head;
        int tail;
        spinlock_t lock;
+       struct list_head qlist;
 };
 
 struct ptp_clock {
@@ -35,7 +37,7 @@ struct ptp_clock {
        int index; /* index into clocks.map */
        struct pps_device *pps_source;
        long dialed_frequency; /* remembers the frequency adjustment */
-       struct timestamp_event_queue tsevq; /* simple fifo for time stamps */
+       struct list_head tsevqs; /* timestamp fifo list */
        struct mutex tsevq_mux; /* one process at a time reading the fifo */
        struct mutex pincfg_mux; /* protect concurrent info->pin_config access */
        wait_queue_head_t tsev_wq;

diff --git a/drivers/ptp/ptp_sysfs.c b/drivers/ptp/ptp_sysfs.c
index 6e4d5456a8851199ed60095ecd92fc4cd45876eb..2675f383cd0ad4ffb69caf07d1e485fabb2c4603 100644 (file)
--- a/drivers/ptp/ptp_sysfs.c
+++ b/drivers/ptp/ptp_sysfs.c
@@ -75,12 +75,16 @@ static ssize_t extts_fifo_show(struct device *dev,
                               struct device_attribute *attr, char *page)
 {
        struct ptp_clock *ptp = dev_get_drvdata(dev);
-       struct timestamp_event_queue *queue = &ptp->tsevq;
+       struct timestamp_event_queue *queue;
        struct ptp_extts_event event;
        unsigned long flags;
        size_t qcnt;
        int cnt = 0;
 
+       /* The sysfs fifo will always draw from the fist queue */
+       queue = list_first_entry(&ptp->tsevqs, struct timestamp_event_queue,
+                                qlist);
+
        memset(&event, 0, sizeof(event));
 
        if (mutex_lock_interruptible(&ptp->tsevq_mux))