Commit 4838bc9e authored by Thomas Gleixner's avatar Thomas Gleixner Committed by Jakub Kicinski
Browse files

ptp: Convert chardev code to lock guards 



Convert the various spin_lock_irqsave() protected critical regions to
scoped guards. Use spinlock_irq instead of spinlock_irqsave as all the
functions are invoked in thread context with interrupts enabled.

No functional change intended.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20250625115133.425029269@linutronix.de


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 745e3c75

drivers/ptp/ptp_chardev.c

+13 −21
Original line number Diff line number Diff line
@@ -110,7 +110,6 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode) 
		container_of(pccontext->clk, struct ptp_clock, clock);

	struct timestamp_event_queue *queue;

	char debugfsname[32];

	unsigned long flags;



	queue = kzalloc(sizeof(*queue), GFP_KERNEL);

	if (!queue)
@@ -122,9 +121,8 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode) 
	}

	bitmap_set(queue->mask, 0, PTP_MAX_CHANNELS);

	spin_lock_init(&queue->lock);

	spin_lock_irqsave(&ptp->tsevqs_lock, flags);

	scoped_guard(spinlock_irq, &ptp->tsevqs_lock)

		list_add_tail(&queue->qlist, &ptp->tsevqs);

	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);

	pccontext->private_clkdata = queue;



	/* Debugfs contents */
@@ -143,15 +141,13 @@ int ptp_open(struct posix_clock_context *pccontext, fmode_t fmode) 
int ptp_release(struct posix_clock_context *pccontext)

{

	struct timestamp_event_queue *queue = pccontext->private_clkdata;

	unsigned long flags;

	struct ptp_clock *ptp =

		container_of(pccontext->clk, struct ptp_clock, clock);



	debugfs_remove(queue->debugfs_instance);

	pccontext->private_clkdata = NULL;

	spin_lock_irqsave(&ptp->tsevqs_lock, flags);

	scoped_guard(spinlock_irq, &ptp->tsevqs_lock)

		list_del(&queue->qlist);

	spin_unlock_irqrestore(&ptp->tsevqs_lock, flags);

	bitmap_free(queue->mask);

	kfree(queue);

	return 0;
@@ -544,8 +540,6 @@ ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags, 
		container_of(pccontext->clk, struct ptp_clock, clock);

	struct timestamp_event_queue *queue;

	struct ptp_extts_event *event;

	unsigned long flags;

	size_t qcnt, i;

	int result;



	queue = pccontext->private_clkdata;
@@ -580,20 +574,18 @@ ssize_t ptp_read(struct posix_clock_context *pccontext, uint rdflags, 
		goto exit;

	}



	spin_lock_irqsave(&queue->lock, flags);



	qcnt = queue_cnt(queue);

	scoped_guard(spinlock_irq, &queue->lock) {

		size_t qcnt = queue_cnt(queue);



		if (cnt > qcnt)

			cnt = qcnt;



	for (i = 0; i < cnt; i++) {

		for (size_t i = 0; i < cnt; i++) {

			event[i] = queue->buf[queue->head];

			/* Paired with READ_ONCE() in queue_cnt() */

			WRITE_ONCE(queue->head, (queue->head + 1) % PTP_MAX_TIMESTAMPS);

		}



	spin_unlock_irqrestore(&queue->lock, flags);

	}



	cnt = cnt * sizeof(struct ptp_extts_event);