[PATCH v5 7/9] coresight-replicator: change replicator_drvdata spinlock's type to raw_spinlock_t
From: Yeoreum Yun <hidden>
Date: 2025-02-25 13:53:53
Also in:
linux-rt-devel, lkml
Subsystem:
arm/coresight framework and drivers, hardware tracing facilities, the rest · Maintainers:
Suzuki K Poulose, Alexander Shishkin, Linus Torvalds
In coresight-replicator drivers, replicator_drvdata->spinlock can be held during __schedule() by perf_event_task_sched_out()/in(). Since replicator_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 replicator_drvdata->spinlock in coresight-replicator drivers, which can be called by perf_event_task_sched_out()/in(), from spinlock_t to raw_spinlock_t. Reviewed-by: James Clark <james.clark@linaro.org> Reviewed-by: Mike Leach <redacted> Signed-off-by: Yeoreum Yun <redacted> --- drivers/hwtracing/coresight/coresight-replicator.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/hwtracing/coresight/coresight-replicator.c b/drivers/hwtracing/coresight/coresight-replicator.c
index a1181c9048c0..ee7ee79f6cf7 100644
--- a/drivers/hwtracing/coresight/coresight-replicator.c
+++ b/drivers/hwtracing/coresight/coresight-replicator.c@@ -41,7 +41,7 @@ struct replicator_drvdata { struct clk *atclk; struct clk *pclk; struct coresight_device *csdev; - spinlock_t spinlock; + raw_spinlock_t spinlock; bool check_idfilter_val; };
@@ -125,7 +125,7 @@ static int replicator_enable(struct coresight_device *csdev, unsigned long flags; bool first_enable = false; - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (out->src_refcnt == 0) { if (drvdata->base) rc = dynamic_replicator_enable(drvdata, in->dest_port,
@@ -135,7 +135,7 @@ static int replicator_enable(struct coresight_device *csdev, } if (!rc) out->src_refcnt++; - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); if (first_enable) dev_dbg(&csdev->dev, "REPLICATOR enabled\n");
@@ -179,14 +179,14 @@ static void replicator_disable(struct coresight_device *csdev, unsigned long flags; bool last_disable = false; - spin_lock_irqsave(&drvdata->spinlock, flags); + raw_spin_lock_irqsave(&drvdata->spinlock, flags); if (--out->src_refcnt == 0) { if (drvdata->base) dynamic_replicator_disable(drvdata, in->dest_port, out->src_port); last_disable = true; } - spin_unlock_irqrestore(&drvdata->spinlock, flags); + raw_spin_unlock_irqrestore(&drvdata->spinlock, flags); if (last_disable) dev_dbg(&csdev->dev, "REPLICATOR disabled\n");
@@ -277,7 +277,7 @@ static int replicator_probe(struct device *dev, struct resource *res) } dev->platform_data = pdata; - spin_lock_init(&drvdata->spinlock); + raw_spin_lock_init(&drvdata->spinlock); desc.type = CORESIGHT_DEV_TYPE_LINK; desc.subtype.link_subtype = CORESIGHT_DEV_SUBTYPE_LINK_SPLIT; desc.ops = &replicator_cs_ops;
--
LEVI:{C3F47F37-75D8-414A-A8BA-3980EC8A46D7}