From 60e5f23dc5d68ec01e6dae8f4311230c7d2ccb8a Mon Sep 17 00:00:00 2001 From: Junhao He Date: Tue, 14 Nov 2023 21:33:46 +0800 Subject: [PATCH] coresight: ultrasoc-smb: Use guards to cleanup Use guards to reduce gotos and simplify control flow. Signed-off-by: Junhao He Reviewed-by: James Clark Signed-off-by: Suzuki K Poulose Link: https://lore.kernel.org/r/20231114133346.30489-5-hejunhao3@huawei.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 2092433ff86e..10e886455b8b 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 @@ out: 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; }