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coresight-replicator: change replicator_drvdata spinlock's type to raw_spinlock_t

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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 <mike.leach@linaro.org>
Signed-off-by: Yeoreum Yun <yeoreum.yun@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20250306121110.1647948-8-yeoreum.yun@arm.com
This commit is contained in:
Yeoreum Yun
2025-03-06 12:11:08 +00:00
committed by Suzuki K Poulose
parent 56eb02f0b0
commit 982d0a0e08
1 changed files with 6 additions and 6 deletions
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12
drivers/hwtracing/coresight/coresight-replicator.c
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@@ -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;