On 14/11/2023 13:33, Junhao He wrote:
Use guards to reduce gotos and simplify control flow.
Signed-off-by: Junhao He hejunhao3@huawei.com
Nice cleanup!
Reviewed-by: James Clark james.clark@arm.com
drivers/hwtracing/coresight/ultrasoc-smb.c | 70 +++++++--------------- 1 file changed, 22 insertions(+), 48 deletions(-)
diff --git a/drivers/hwtracing/coresight/ultrasoc-smb.c b/drivers/hwtracing/coresight/ultrasoc-smb.c index 6e32d31a95fe..cd14b2eded4e 100644 --- a/drivers/hwtracing/coresight/ultrasoc-smb.c +++ b/drivers/hwtracing/coresight/ultrasoc-smb.c @@ -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; }