Commit 0916447c authored by Mathieu Poirier's avatar Mathieu Poirier Committed by Greg Kroah-Hartman
Browse files

coresight: Properly address concurrency in sink::update() functions 



When operating in CPU-wide trace scenarios and working with an N:1
source/sink HW topology, update() functions need to be made atomic
in order to avoid racing with start and stop operations.

Signed-off-by: default avatarMathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: default avatarLeo Yan <leo.yan@linaro.org>
Tested-by: default avatarRobert Walker <robert.walker@arm.com>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 12dfc9e0

drivers/hwtracing/coresight/coresight-etb10.c

+3 −1
Original line number Diff line number Diff line
@@ -405,7 +405,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, 
	const u32 *barrier;

	u32 read_ptr, write_ptr, capacity;

	u32 status, read_data;

	unsigned long offset, to_read;

	unsigned long offset, to_read, flags;

	struct cs_buffers *buf = sink_config;

	struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -414,6 +414,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, 


	capacity = drvdata->buffer_depth * ETB_FRAME_SIZE_WORDS;



	spin_lock_irqsave(&drvdata->spinlock, flags);

	__etb_disable_hw(drvdata);

	CS_UNLOCK(drvdata->base);
@@ -524,6 +525,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev, 
	}

	__etb_enable_hw(drvdata);

	CS_LOCK(drvdata->base);

	spin_unlock_irqrestore(&drvdata->spinlock, flags);



	return to_read;

}

drivers/hwtracing/coresight/coresight-tmc-etf.c

+3 −1
Original line number Diff line number Diff line
@@ -413,7 +413,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, 
	u32 *buf_ptr;

	u64 read_ptr, write_ptr;

	u32 status;

	unsigned long offset, to_read;

	unsigned long offset, to_read, flags;

	struct cs_buffers *buf = sink_config;

	struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -424,6 +424,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, 
	if (WARN_ON_ONCE(drvdata->mode != CS_MODE_PERF))

		return 0;



	spin_lock_irqsave(&drvdata->spinlock, flags);

	CS_UNLOCK(drvdata->base);



	tmc_flush_and_stop(drvdata);
@@ -517,6 +518,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev, 
		to_read = buf->nr_pages << PAGE_SHIFT;

	}

	CS_LOCK(drvdata->base);

	spin_unlock_irqrestore(&drvdata->spinlock, flags);



	return to_read;

}

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