Commit 60e5f23d authored by Junhao He's avatar Junhao He Committed by Suzuki K Poulose
Browse files

coresight: ultrasoc-smb: Use guards to cleanup 



Use guards to reduce gotos and simplify control flow.

Signed-off-by: default avatarJunhao He <hejunhao3@huawei.com>
Reviewed-by: default avatarJames Clark <james.clark@arm.com>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20231114133346.30489-5-hejunhao3@huawei.com
parent 32d9a78b

drivers/hwtracing/coresight/ultrasoc-smb.c

+22 −48
Original line number Diff line number Diff line
@@ -97,27 +97,19 @@ static int smb_open(struct inode *inode, struct file *file) 
{

	struct smb_drv_data *drvdata = container_of(file->private_data,

					struct smb_drv_data, miscdev);

	int ret = 0;



	spin_lock(&drvdata->spinlock);

	guard(spinlock)(&drvdata->spinlock);



	if (drvdata->reading) {

		ret = -EBUSY;

		goto out;

	}

	if (drvdata->reading)

		return -EBUSY;



	if (atomic_read(&drvdata->csdev->refcnt)) {

		ret = -EBUSY;

		goto out;

	}

	if (atomic_read(&drvdata->csdev->refcnt))

		return -EBUSY;



	smb_update_data_size(drvdata);



	drvdata->reading = true;

out:

	spin_unlock(&drvdata->spinlock);



	return ret;

	return 0;

}



static ssize_t smb_read(struct file *file, char __user *data, size_t len,
@@ -160,9 +152,8 @@ static int smb_release(struct inode *inode, struct file *file) 
	struct smb_drv_data *drvdata = container_of(file->private_data,

					struct smb_drv_data, miscdev);



	spin_lock(&drvdata->spinlock);

	guard(spinlock)(&drvdata->spinlock);

	drvdata->reading = false;

	spin_unlock(&drvdata->spinlock);



	return 0;

}
@@ -255,19 +246,15 @@ static int smb_enable(struct coresight_device *csdev, enum cs_mode mode, 
	struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent);

	int ret = 0;



	spin_lock(&drvdata->spinlock);

	guard(spinlock)(&drvdata->spinlock);



	/* Do nothing, the trace data is reading by other interface now */

	if (drvdata->reading) {

		ret = -EBUSY;

		goto out;

	}

	if (drvdata->reading)

		return -EBUSY;



	/* Do nothing, the SMB is already enabled as other mode */

	if (drvdata->mode != CS_MODE_DISABLED && drvdata->mode != mode) {

		ret = -EBUSY;

		goto out;

	}

	if (drvdata->mode != CS_MODE_DISABLED && drvdata->mode != mode)

		return -EBUSY;



	switch (mode) {

	case CS_MODE_SYSFS:
@@ -281,13 +268,10 @@ static int smb_enable(struct coresight_device *csdev, enum cs_mode mode, 
	}



	if (ret)

		goto out;

		return ret;



	atomic_inc(&csdev->refcnt);



	dev_dbg(&csdev->dev, "Ultrasoc SMB enabled\n");

out:

	spin_unlock(&drvdata->spinlock);



	return ret;

}
@@ -295,19 +279,14 @@ static int smb_enable(struct coresight_device *csdev, enum cs_mode mode, 
static int smb_disable(struct coresight_device *csdev)

{

	struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent);

	int ret = 0;



	spin_lock(&drvdata->spinlock);

	guard(spinlock)(&drvdata->spinlock);



	if (drvdata->reading) {

		ret = -EBUSY;

		goto out;

	}

	if (drvdata->reading)

		return -EBUSY;



	if (atomic_dec_return(&csdev->refcnt)) {

		ret = -EBUSY;

		goto out;

	}

	if (atomic_dec_return(&csdev->refcnt))

		return -EBUSY;



	/* Complain if we (somehow) got out of sync */

	WARN_ON_ONCE(drvdata->mode == CS_MODE_DISABLED);
@@ -317,12 +296,9 @@ static int smb_disable(struct coresight_device *csdev) 
	/* Dissociate from the target process. */

	drvdata->pid = -1;

	drvdata->mode = CS_MODE_DISABLED;



	dev_dbg(&csdev->dev, "Ultrasoc SMB disabled\n");

out:

	spin_unlock(&drvdata->spinlock);



	return ret;

	return 0;

}



static void *smb_alloc_buffer(struct coresight_device *csdev,
@@ -395,17 +371,17 @@ static unsigned long smb_update_buffer(struct coresight_device *csdev, 
	struct smb_drv_data *drvdata = dev_get_drvdata(csdev->dev.parent);

	struct smb_data_buffer *sdb = &drvdata->sdb;

	struct cs_buffers *buf = sink_config;

	unsigned long data_size = 0;

	unsigned long data_size;

	bool lost = false;



	if (!buf)

		return 0;



	spin_lock(&drvdata->spinlock);

	guard(spinlock)(&drvdata->spinlock);



	/* Don't do anything if another tracer is using this sink. */

	if (atomic_read(&csdev->refcnt) != 1)

		goto out;

		return 0;



	smb_disable_hw(drvdata);

	smb_update_data_size(drvdata);
@@ -424,8 +400,6 @@ static unsigned long smb_update_buffer(struct coresight_device *csdev, 
	smb_sync_perf_buffer(drvdata, buf, handle->head);

	if (!buf->snapshot && lost)

		perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED);

out:

	spin_unlock(&drvdata->spinlock);



	return data_size;

}