diff options
| author | Mathieu Poirier <mathieu.poirier@linaro.org> | 2019-03-30 16:54:58 -0600 |
|---|---|---|
| committer | Mathieu Poirier <mathieu.poirier@linaro.org> | 2019-04-03 04:17:30 -0600 |
| commit | c635822c8dbdb6be347b0e85bf492834236b4c51 (patch) | |
| tree | fa929bcf12e023decc711d240d50f9b93e382419 | |
| parent | 3f2df3026227cc17c89e5039e9e7f2fa45599c62 (diff) | |
coresight: tmc-etr: Introduce the notion of reference counting to ETR devices
This patch adds reference counting to struct etr_buf so that, in CPU-wide
trace scenarios, shared buffers can be disposed of when no longer used.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc-etr.c | 5 | ||||
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc.h | 3 |
2 files changed, 8 insertions, 0 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index e1774d4bb5f3..1346474ac019 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -8,6 +8,7 @@ #include <linux/coresight.h> #include <linux/dma-mapping.h> #include <linux/iommu.h> +#include <linux/refcount.h> #include <linux/slab.h> #include <linux/types.h> #include <linux/vmalloc.h> @@ -1221,7 +1222,11 @@ get_perf_etr_buf_per_thread(struct tmc_drvdata *drvdata, * with memory allocation. */ etr_buf = alloc_etr_buf(drvdata, event, nr_pages, pages, snapshot); + if (IS_ERR(etr_buf)) + goto out; + refcount_set(&etr_buf->refcount, 1); +out: return etr_buf; } diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h index 487c53701e9c..ee44906dffe8 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.h +++ b/drivers/hwtracing/coresight/coresight-tmc.h @@ -9,6 +9,7 @@ #include <linux/dma-mapping.h> #include <linux/miscdevice.h> +#include <linux/refcount.h> #define TMC_RSZ 0x004 #define TMC_STS 0x00c @@ -133,6 +134,7 @@ struct etr_buf_operations; /** * struct etr_buf - Details of the buffer used by ETR + * refcount ; Number of sources currently using this etr_buf. * @mode : Mode of the ETR buffer, contiguous, Scatter Gather etc. * @full : Trace data overflow * @size : Size of the buffer. @@ -143,6 +145,7 @@ struct etr_buf_operations; * @private : Backend specific information for the buf */ struct etr_buf { + refcount_t refcount; enum etr_mode mode; bool full; ssize_t size; |