[PATCH 8/9] coresight-tmc: change tmc_drvdata spinlock's type to raw_spinlock_t
Yeoreum Yun
yeoreum.yun at arm.com
Mon Nov 25 01:48:15 PST 2024
From: Levi Yun <yeoreum.yun at arm.com>
In coresight-tmc drivers, tmc_drvdata->spinlock can be held
during __schedule() by perf_event_task_sched_out()/in().
Since tmc_drvdata->spinlock type is spinlock_t and
perf_event_task_sched_out()/in() is called after acquiring rq_lock,
which is raw_spinlock_t (an unsleepable lock),
this poses an issue in PREEMPT_RT kernel where spinlock_t is sleepable.
To address this, change type tmc_drvdata->spinlock in coresight-tmc drivers,
which can be called by perf_event_task_sched_out()/in(),
from spinlock_t to raw_spinlock_t.
Signed-off-by: Yeoreum Yun <yeoreum.yun at arm.com>
---
.../hwtracing/coresight/coresight-tmc-core.c | 9 +-
.../hwtracing/coresight/coresight-tmc-etf.c | 195 +++++++----------
.../hwtracing/coresight/coresight-tmc-etr.c | 199 ++++++++----------
drivers/hwtracing/coresight/coresight-tmc.h | 2 +-
4 files changed, 169 insertions(+), 236 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-core.c b/drivers/hwtracing/coresight/coresight-tmc-core.c
index 3a482fd2cb22..d6499eb14745 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-core.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-core.c
@@ -492,7 +492,7 @@ static int __tmc_probe(struct device *dev, struct resource *res)
drvdata->base = base;
desc.access = CSDEV_ACCESS_IOMEM(base);
- spin_lock_init(&drvdata->spinlock);
+ raw_spin_lock_init(&drvdata->spinlock);
devid = readl_relaxed(drvdata->base + CORESIGHT_DEVID);
drvdata->config_type = BMVAL(devid, 6, 7);
@@ -593,13 +593,12 @@ static int tmc_probe(struct amba_device *adev, const struct amba_id *id)
static void tmc_shutdown(struct amba_device *adev)
{
- unsigned long flags;
struct tmc_drvdata *drvdata = amba_get_drvdata(adev);
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
if (coresight_get_mode(drvdata->csdev) == CS_MODE_DISABLED)
- goto out;
+ return;
if (drvdata->config_type == TMC_CONFIG_TYPE_ETR)
tmc_etr_disable_hw(drvdata);
@@ -609,8 +608,6 @@ static void tmc_shutdown(struct amba_device *adev)
* callback which is required for making coresight modular since
* the system is going down after this.
*/
-out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
}
static void __tmc_remove(struct device *dev)
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etf.c b/drivers/hwtracing/coresight/coresight-tmc-etf.c
index d4f641cd9de6..b2f97defbba2 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etf.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etf.c
@@ -182,9 +182,9 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
* If we don't have a buffer release the lock and allocate memory.
* Otherwise keep the lock and move along.
*/
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ raw_spin_lock_irqsave(&drvdata->spinlock, flags);
if (!drvdata->buf) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
/* Allocating the memory here while outside of the spinlock */
buf = kzalloc(drvdata->size, GFP_KERNEL);
@@ -192,7 +192,7 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
return -ENOMEM;
/* Let's try again */
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ raw_spin_lock_irqsave(&drvdata->spinlock, flags);
}
if (drvdata->reading) {
@@ -235,7 +235,7 @@ static int tmc_enable_etf_sink_sysfs(struct coresight_device *csdev)
used = false;
}
out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
/* Free memory outside the spinlock if need be */
if (!used)
@@ -248,12 +248,12 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
{
int ret = 0;
pid_t pid;
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct perf_output_handle *handle = data;
struct cs_buffers *buf = etm_perf_sink_config(handle);
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
+
do {
ret = -EINVAL;
if (drvdata->reading)
@@ -296,7 +296,6 @@ static int tmc_enable_etf_sink_perf(struct coresight_device *csdev, void *data)
csdev->refcnt++;
}
} while (0);
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
return ret;
}
@@ -328,31 +327,24 @@ static int tmc_enable_etf_sink(struct coresight_device *csdev,
static int tmc_disable_etf_sink(struct coresight_device *csdev)
{
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ if (drvdata->reading)
+ return -EBUSY;
- if (drvdata->reading) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EBUSY;
- }
+ csdev->refcnt--;
+ if (csdev->refcnt)
+ return -EBUSY;
- csdev->refcnt--;
- if (csdev->refcnt) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EBUSY;
+ /* Complain if we (somehow) got out of sync */
+ WARN_ON_ONCE(coresight_get_mode(csdev) == CS_MODE_DISABLED);
+ tmc_etb_disable_hw(drvdata);
+ /* Dissociate from monitored process. */
+ drvdata->pid = -1;
+ coresight_set_mode(csdev, CS_MODE_DISABLED);
}
- /* Complain if we (somehow) got out of sync */
- WARN_ON_ONCE(coresight_get_mode(csdev) == CS_MODE_DISABLED);
- tmc_etb_disable_hw(drvdata);
- /* Dissociate from monitored process. */
- drvdata->pid = -1;
- coresight_set_mode(csdev, CS_MODE_DISABLED);
-
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
dev_dbg(&csdev->dev, "TMC-ETB/ETF disabled\n");
return 0;
}
@@ -362,26 +354,23 @@ static int tmc_enable_etf_link(struct coresight_device *csdev,
struct coresight_connection *out)
{
int ret = 0;
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
bool first_enable = false;
- spin_lock_irqsave(&drvdata->spinlock, flags);
- if (drvdata->reading) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EBUSY;
- }
-
- if (csdev->refcnt == 0) {
- ret = tmc_etf_enable_hw(drvdata);
- if (!ret) {
- coresight_set_mode(csdev, CS_MODE_SYSFS);
- first_enable = true;
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ if (drvdata->reading)
+ return -EBUSY;
+
+ if (csdev->refcnt == 0) {
+ ret = tmc_etf_enable_hw(drvdata);
+ if (!ret) {
+ coresight_set_mode(csdev, CS_MODE_SYSFS);
+ first_enable = true;
+ }
}
+ if (!ret)
+ csdev->refcnt++;
}
- if (!ret)
- csdev->refcnt++;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
if (first_enable)
dev_dbg(&csdev->dev, "TMC-ETF enabled\n");
@@ -392,23 +381,20 @@ static void tmc_disable_etf_link(struct coresight_device *csdev,
struct coresight_connection *in,
struct coresight_connection *out)
{
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
bool last_disable = false;
- spin_lock_irqsave(&drvdata->spinlock, flags);
- if (drvdata->reading) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return;
- }
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ if (drvdata->reading)
+ return;
- csdev->refcnt--;
- if (csdev->refcnt == 0) {
- tmc_etf_disable_hw(drvdata);
- coresight_set_mode(csdev, CS_MODE_DISABLED);
- last_disable = true;
+ csdev->refcnt--;
+ if (csdev->refcnt == 0) {
+ tmc_etf_disable_hw(drvdata);
+ coresight_set_mode(csdev, CS_MODE_DISABLED);
+ last_disable = true;
+ }
}
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
if (last_disable)
dev_dbg(&csdev->dev, "TMC-ETF disabled\n");
@@ -477,7 +463,7 @@ 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 = 0, flags;
+ unsigned long offset, to_read = 0;
struct cs_buffers *buf = sink_config;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -488,11 +474,11 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
if (WARN_ON_ONCE(coresight_get_mode(csdev) != CS_MODE_PERF))
return 0;
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
/* Don't do anything if another tracer is using this sink */
if (csdev->refcnt != 1)
- goto out;
+ return 0;
CS_UNLOCK(drvdata->base);
@@ -584,8 +570,6 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
* is expected by the perf ring buffer.
*/
CS_LOCK(drvdata->base);
-out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
return to_read;
}
@@ -615,56 +599,43 @@ const struct coresight_ops tmc_etf_cs_ops = {
int tmc_read_prepare_etb(struct tmc_drvdata *drvdata)
{
enum tmc_mode mode;
- int ret = 0;
- unsigned long flags;
/* config types are set a boot time and never change */
if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETB &&
drvdata->config_type != TMC_CONFIG_TYPE_ETF))
return -EINVAL;
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
- if (drvdata->reading) {
- ret = -EBUSY;
- goto out;
- }
+ if (drvdata->reading)
+ return -EBUSY;
/* Don't interfere if operated from Perf */
- if (coresight_get_mode(drvdata->csdev) == CS_MODE_PERF) {
- ret = -EINVAL;
- goto out;
- }
+ if (coresight_get_mode(drvdata->csdev) == CS_MODE_PERF)
+ return -EINVAL;
/* If drvdata::buf is NULL the trace data has been read already */
- if (drvdata->buf == NULL) {
- ret = -EINVAL;
- goto out;
- }
+ if (drvdata->buf == NULL)
+ return -EINVAL;
/* Disable the TMC if need be */
if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS) {
/* There is no point in reading a TMC in HW FIFO mode */
mode = readl_relaxed(drvdata->base + TMC_MODE);
- if (mode != TMC_MODE_CIRCULAR_BUFFER) {
- ret = -EINVAL;
- goto out;
- }
+ if (mode != TMC_MODE_CIRCULAR_BUFFER)
+ return -EINVAL;
__tmc_etb_disable_hw(drvdata);
}
drvdata->reading = true;
-out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return ret;
+ return 0;
}
int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
{
char *buf = NULL;
enum tmc_mode mode;
- unsigned long flags;
int rc = 0;
/* config types are set a boot time and never change */
@@ -672,41 +643,37 @@ int tmc_read_unprepare_etb(struct tmc_drvdata *drvdata)
drvdata->config_type != TMC_CONFIG_TYPE_ETF))
return -EINVAL;
- spin_lock_irqsave(&drvdata->spinlock, flags);
-
- /* Re-enable the TMC if need be */
- if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS) {
- /* There is no point in reading a TMC in HW FIFO mode */
- mode = readl_relaxed(drvdata->base + TMC_MODE);
- if (mode != TMC_MODE_CIRCULAR_BUFFER) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EINVAL;
- }
- /*
- * The trace run will continue with the same allocated trace
- * buffer. As such zero-out the buffer so that we don't end
- * up with stale data.
- *
- * Since the tracer is still enabled drvdata::buf
- * can't be NULL.
- */
- memset(drvdata->buf, 0, drvdata->size);
- rc = __tmc_etb_enable_hw(drvdata);
- if (rc) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return rc;
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ /* Re-enable the TMC if need be */
+ if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS) {
+ /* There is no point in reading a TMC in HW FIFO mode */
+ mode = readl_relaxed(drvdata->base + TMC_MODE);
+ if (mode != TMC_MODE_CIRCULAR_BUFFER)
+ return -EINVAL;
+
+ /*
+ * The trace run will continue with the same allocated trace
+ * buffer. As such zero-out the buffer so that we don't end
+ * up with stale data.
+ *
+ * Since the tracer is still enabled drvdata::buf
+ * can't be NULL.
+ */
+ memset(drvdata->buf, 0, drvdata->size);
+ rc = __tmc_etb_enable_hw(drvdata);
+ if (rc)
+ return rc;
+ } else {
+ /*
+ * The ETB/ETF is not tracing and the buffer was just read.
+ * As such prepare to free the trace buffer.
+ */
+ buf = drvdata->buf;
+ drvdata->buf = NULL;
}
- } else {
- /*
- * The ETB/ETF is not tracing and the buffer was just read.
- * As such prepare to free the trace buffer.
- */
- buf = drvdata->buf;
- drvdata->buf = NULL;
- }
- drvdata->reading = false;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ drvdata->reading = false;
+ }
/*
* Free allocated memory outside of the spinlock. There is no need
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c
index a48bb85d0e7f..6672bea4d2b9 100644
--- a/drivers/hwtracing/coresight/coresight-tmc-etr.c
+++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c
@@ -1176,10 +1176,10 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)
* buffer, provided the size matches. Any allocation has to be done
* with the lock released.
*/
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ raw_spin_lock_irqsave(&drvdata->spinlock, flags);
sysfs_buf = READ_ONCE(drvdata->sysfs_buf);
if (!sysfs_buf || (sysfs_buf->size != drvdata->size)) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
/* Allocate memory with the locks released */
free_buf = new_buf = tmc_etr_setup_sysfs_buf(drvdata);
@@ -1187,7 +1187,7 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)
return new_buf;
/* Let's try again */
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ raw_spin_lock_irqsave(&drvdata->spinlock, flags);
}
if (drvdata->reading || coresight_get_mode(csdev) == CS_MODE_PERF) {
@@ -1206,7 +1206,7 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)
}
out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ raw_spin_unlock_irqrestore(&drvdata->spinlock, flags);
/* Free memory outside the spinlock if need be */
if (free_buf)
@@ -1216,35 +1216,31 @@ static struct etr_buf *tmc_etr_get_sysfs_buffer(struct coresight_device *csdev)
static int tmc_enable_etr_sink_sysfs(struct coresight_device *csdev)
{
- int ret = 0;
- unsigned long flags;
+ int ret;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct etr_buf *sysfs_buf = tmc_etr_get_sysfs_buffer(csdev);
if (IS_ERR(sysfs_buf))
return PTR_ERR(sysfs_buf);
- spin_lock_irqsave(&drvdata->spinlock, flags);
-
- /*
- * In sysFS mode we can have multiple writers per sink. Since this
- * sink is already enabled no memory is needed and the HW need not be
- * touched, even if the buffer size has changed.
- */
- if (coresight_get_mode(csdev) == CS_MODE_SYSFS) {
- csdev->refcnt++;
- goto out;
- }
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ /*
+ * In sysFS mode we can have multiple writers per sink. Since this
+ * sink is already enabled no memory is needed and the HW need not be
+ * touched, even if the buffer size has changed.
+ */
+ if (coresight_get_mode(csdev) == CS_MODE_SYSFS) {
+ csdev->refcnt++;
+ return 0;
+ }
- ret = tmc_etr_enable_hw(drvdata, sysfs_buf);
- if (!ret) {
- coresight_set_mode(csdev, CS_MODE_SYSFS);
- csdev->refcnt++;
+ ret = tmc_etr_enable_hw(drvdata, sysfs_buf);
+ if (!ret) {
+ coresight_set_mode(csdev, CS_MODE_SYSFS);
+ csdev->refcnt++;
+ }
}
-out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
if (!ret)
dev_dbg(&csdev->dev, "TMC-ETR enabled\n");
@@ -1557,32 +1553,28 @@ tmc_update_etr_buffer(struct coresight_device *csdev,
void *config)
{
bool lost = false;
- unsigned long flags, offset, size = 0;
+ unsigned long offset, size = 0;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct etr_perf_buffer *etr_perf = config;
struct etr_buf *etr_buf = etr_perf->etr_buf;
- spin_lock_irqsave(&drvdata->spinlock, flags);
-
- /* Don't do anything if another tracer is using this sink */
- if (csdev->refcnt != 1) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- goto out;
- }
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ /* Don't do anything if another tracer is using this sink */
+ if (csdev->refcnt != 1)
+ goto out;
- if (WARN_ON(drvdata->perf_buf != etr_buf)) {
- lost = true;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- goto out;
- }
+ if (WARN_ON(drvdata->perf_buf != etr_buf)) {
+ lost = true;
+ goto out;
+ }
- CS_UNLOCK(drvdata->base);
+ CS_UNLOCK(drvdata->base);
- tmc_flush_and_stop(drvdata);
- tmc_sync_etr_buf(drvdata);
+ tmc_flush_and_stop(drvdata);
+ tmc_sync_etr_buf(drvdata);
- CS_LOCK(drvdata->base);
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
+ CS_LOCK(drvdata->base);
+ }
lost = etr_buf->full;
offset = etr_buf->offset;
@@ -1644,33 +1636,27 @@ tmc_update_etr_buffer(struct coresight_device *csdev,
static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
{
- int rc = 0;
+ int rc;
pid_t pid;
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
struct perf_output_handle *handle = data;
struct etr_perf_buffer *etr_perf = etm_perf_sink_config(handle);
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
+
/* Don't use this sink if it is already claimed by sysFS */
- if (coresight_get_mode(csdev) == CS_MODE_SYSFS) {
- rc = -EBUSY;
- goto unlock_out;
- }
+ if (coresight_get_mode(csdev) == CS_MODE_SYSFS)
+ return -EBUSY;
- if (WARN_ON(!etr_perf || !etr_perf->etr_buf)) {
- rc = -EINVAL;
- goto unlock_out;
- }
+ if (WARN_ON(!etr_perf || !etr_perf->etr_buf))
+ return -EINVAL;
/* Get a handle on the pid of the session owner */
pid = etr_perf->pid;
/* Do not proceed if this device is associated with another session */
- if (drvdata->pid != -1 && drvdata->pid != pid) {
- rc = -EBUSY;
- goto unlock_out;
- }
+ if (drvdata->pid != -1 && drvdata->pid != pid)
+ return -EBUSY;
/*
* No HW configuration is needed if the sink is already in
@@ -1678,7 +1664,7 @@ static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
*/
if (drvdata->pid == pid) {
csdev->refcnt++;
- goto unlock_out;
+ return 0;
}
rc = tmc_etr_enable_hw(drvdata, etr_perf->etr_buf);
@@ -1690,8 +1676,6 @@ static int tmc_enable_etr_sink_perf(struct coresight_device *csdev, void *data)
csdev->refcnt++;
}
-unlock_out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
return rc;
}
@@ -1710,33 +1694,26 @@ static int tmc_enable_etr_sink(struct coresight_device *csdev,
static int tmc_disable_etr_sink(struct coresight_device *csdev)
{
- unsigned long flags;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
- spin_lock_irqsave(&drvdata->spinlock, flags);
-
- if (drvdata->reading) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EBUSY;
- }
-
- csdev->refcnt--;
- if (csdev->refcnt) {
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
- return -EBUSY;
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ if (drvdata->reading)
+ return -EBUSY;
+
+ csdev->refcnt--;
+ if (csdev->refcnt)
+ return -EBUSY;
+
+ /* Complain if we (somehow) got out of sync */
+ WARN_ON_ONCE(coresight_get_mode(csdev) == CS_MODE_DISABLED);
+ tmc_etr_disable_hw(drvdata);
+ /* Dissociate from monitored process. */
+ drvdata->pid = -1;
+ coresight_set_mode(csdev, CS_MODE_DISABLED);
+ /* Reset perf specific data */
+ drvdata->perf_buf = NULL;
}
- /* Complain if we (somehow) got out of sync */
- WARN_ON_ONCE(coresight_get_mode(csdev) == CS_MODE_DISABLED);
- tmc_etr_disable_hw(drvdata);
- /* Dissociate from monitored process. */
- drvdata->pid = -1;
- coresight_set_mode(csdev, CS_MODE_DISABLED);
- /* Reset perf specific data */
- drvdata->perf_buf = NULL;
-
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
dev_dbg(&csdev->dev, "TMC-ETR disabled\n");
return 0;
}
@@ -1756,70 +1733,62 @@ const struct coresight_ops tmc_etr_cs_ops = {
int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
{
int ret = 0;
- unsigned long flags;
/* config types are set a boot time and never change */
if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
return -EINVAL;
- spin_lock_irqsave(&drvdata->spinlock, flags);
- if (drvdata->reading) {
- ret = -EBUSY;
- goto out;
- }
+ guard(raw_spinlock_irqsave)(&drvdata->spinlock);
+
+ if (drvdata->reading)
+ return -EBUSY;
/*
* We can safely allow reads even if the ETR is operating in PERF mode,
* since the sysfs session is captured in mode specific data.
* If drvdata::sysfs_data is NULL the trace data has been read already.
*/
- if (!drvdata->sysfs_buf) {
- ret = -EINVAL;
- goto out;
- }
+ if (!drvdata->sysfs_buf)
+ return -EINVAL;
/* Disable the TMC if we are trying to read from a running session. */
if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS)
__tmc_etr_disable_hw(drvdata);
drvdata->reading = true;
-out:
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
return ret;
}
int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
{
- unsigned long flags;
struct etr_buf *sysfs_buf = NULL;
/* config types are set a boot time and never change */
if (WARN_ON_ONCE(drvdata->config_type != TMC_CONFIG_TYPE_ETR))
return -EINVAL;
- spin_lock_irqsave(&drvdata->spinlock, flags);
+ scoped_guard(raw_spinlock_irqsave, &drvdata->spinlock) {
+ /* RE-enable the TMC if need be */
+ if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS) {
+ /*
+ * The trace run will continue with the same allocated trace
+ * buffer. Since the tracer is still enabled drvdata::buf can't
+ * be NULL.
+ */
+ __tmc_etr_enable_hw(drvdata);
+ } else {
+ /*
+ * The ETR is not tracing and the buffer was just read.
+ * As such prepare to free the trace buffer.
+ */
+ sysfs_buf = drvdata->sysfs_buf;
+ drvdata->sysfs_buf = NULL;
+ }
- /* RE-enable the TMC if need be */
- if (coresight_get_mode(drvdata->csdev) == CS_MODE_SYSFS) {
- /*
- * The trace run will continue with the same allocated trace
- * buffer. Since the tracer is still enabled drvdata::buf can't
- * be NULL.
- */
- __tmc_etr_enable_hw(drvdata);
- } else {
- /*
- * The ETR is not tracing and the buffer was just read.
- * As such prepare to free the trace buffer.
- */
- sysfs_buf = drvdata->sysfs_buf;
- drvdata->sysfs_buf = NULL;
+ drvdata->reading = false;
}
- drvdata->reading = false;
- spin_unlock_irqrestore(&drvdata->spinlock, flags);
-
/* Free allocated memory out side of the spinlock */
if (sysfs_buf)
tmc_etr_free_sysfs_buf(sysfs_buf);
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h
index 2671926be62a..60b395025bc4 100644
--- a/drivers/hwtracing/coresight/coresight-tmc.h
+++ b/drivers/hwtracing/coresight/coresight-tmc.h
@@ -195,7 +195,7 @@ struct tmc_drvdata {
void __iomem *base;
struct coresight_device *csdev;
struct miscdevice miscdev;
- spinlock_t spinlock;
+ raw_spinlock_t spinlock;
pid_t pid;
bool reading;
union {
--
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}
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