UPSTREAM: coresight: Properly address concurrency in sink::update() functions

(Upstream commit 0916447c87).

When operating in CPU-wide trace scenarios and working with an N:1
source/sink HW topology, update() functions need to be made atomic
in order to avoid racing with start and stop operations.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Tested-by: Leo Yan <leo.yan@linaro.org>
Tested-by: Robert Walker <robert.walker@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bug: 140266694
Change-Id: If16c146cc4721acc005c7db3d88e57d38fe48ece
Signed-off-by: Yabin Cui <yabinc@google.com>
This commit is contained in:
Mathieu Poirier
2019-04-25 13:52:58 -06:00
committed by Yabin Cui
parent 14b9467147
commit 0efc646aa8
2 changed files with 6 additions and 2 deletions

View File

@@ -413,7 +413,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev,
const u32 *barrier;
u32 read_ptr, write_ptr, capacity;
u32 status, read_data;
unsigned long offset, to_read;
unsigned long offset, to_read, flags;
struct cs_buffers *buf = sink_config;
struct etb_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -422,6 +422,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev,
capacity = drvdata->buffer_depth * ETB_FRAME_SIZE_WORDS;
spin_lock_irqsave(&drvdata->spinlock, flags);
__etb_disable_hw(drvdata);
CS_UNLOCK(drvdata->base);
@@ -532,6 +533,7 @@ static unsigned long etb_update_buffer(struct coresight_device *csdev,
}
__etb_enable_hw(drvdata);
CS_LOCK(drvdata->base);
spin_unlock_irqrestore(&drvdata->spinlock, flags);
return to_read;
}

View File

@@ -416,7 +416,7 @@ 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;
unsigned long offset, to_read, flags;
struct cs_buffers *buf = sink_config;
struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent);
@@ -427,6 +427,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
if (WARN_ON_ONCE(drvdata->mode != CS_MODE_PERF))
return 0;
spin_lock_irqsave(&drvdata->spinlock, flags);
CS_UNLOCK(drvdata->base);
tmc_flush_and_stop(drvdata);
@@ -520,6 +521,7 @@ static unsigned long tmc_update_etf_buffer(struct coresight_device *csdev,
to_read = buf->nr_pages << PAGE_SHIFT;
}
CS_LOCK(drvdata->base);
spin_unlock_irqrestore(&drvdata->spinlock, flags);
return to_read;
}