diff options
| author | Mathieu Poirier <mathieu.poirier@linaro.org> | 2016-05-03 11:33:53 -0600 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-05-03 14:59:30 -0700 |
| commit | f74debbea0885ebb65fb3fa4e598323f40b03f5f (patch) | |
| tree | e103d1b63fa7d710354ca2ec80e7ec38cf47fe60 /drivers/hwtracing/coresight/coresight-tmc.h | |
| parent | de5461970b3e9e19470b821f5feaa3235ceb35f5 (diff) | |
coresight: tmc: getting rid of multiple read access
Allowing multiple readers to access the trace data simultaniously
via sysFS provides no shortage of opportunity for race condition,
mandates two variable to be maintained (drvdata::read_count and
drvdata::reading), makes the code complex and provide little
advantages, if any.
This patch streamlines the read process by restricting trace data
access to a single user. That way drvdata::read_count can
be eliminated and race conditions (along with faulty error handling)
in function tmc_open() and tmc_release() eliminated.
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing/coresight/coresight-tmc.h')
| -rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc.h | 2 |
1 files changed, 0 insertions, 2 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc.h b/drivers/hwtracing/coresight/coresight-tmc.h index df661903f83c..592eb149fe3a 100644 --- a/drivers/hwtracing/coresight/coresight-tmc.h +++ b/drivers/hwtracing/coresight/coresight-tmc.h @@ -94,7 +94,6 @@ enum tmc_mem_intf_width { * @csdev: component vitals needed by the framework. * @miscdev: specifics to handle "/dev/xyz.tmc" entry. * @spinlock: only one at a time pls. - * @read_count: manages preparation of buffer for reading. * @buf: area of memory where trace data get sent. * @paddr: DMA start location in RAM. * @vaddr: virtual representation of @paddr. @@ -109,7 +108,6 @@ struct tmc_drvdata { struct coresight_device *csdev; struct miscdevice miscdev; spinlock_t spinlock; - int read_count; bool reading; char *buf; dma_addr_t paddr; |