Re: [PATCH v10 09/24] coresight: etm3x: allow etm3x to be built as a module

From: Suzuki K Poulose
Date: Sun Sep 13 2020 - 09:13:52 EST


On 08/21/2020 04:44 AM, Tingwei Zhang wrote:
From: Kim Phillips <kim.phillips@xxxxxxx>

Allow to build coresight-etm3x as a module, for ease of development.

- Kconfig becomes a tristate, to allow =m
- append -core to source file name to allow module to
be called coresight-etm3x by the Makefile
- add an etm_remove function, for module unload
- add a MODULE_DEVICE_TABLE for autoloading on boot

Cc: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Cc: Leo Yan <leo.yan@xxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
Cc: Suzuki K Poulose <Suzuki.Poulose@xxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Russell King <linux@xxxxxxxxxxxxxxx>
Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
Signed-off-by: Tingwei Zhang <tingwei@xxxxxxxxxxxxxx>
Reviewed-by: Mike Leach <mike.leach@xxxxxxxxxx>


diff --git a/drivers/hwtracing/coresight/coresight-etm3x.c b/drivers/hwtracing/coresight/coresight-etm3x-core.c
similarity index 97%
rename from drivers/hwtracing/coresight/coresight-etm3x.c
rename to drivers/hwtracing/coresight/coresight-etm3x-core.c
index bf22dcfd3327..ba9c86497acb 100644
--- a/drivers/hwtracing/coresight/coresight-etm3x.c
+++ b/drivers/hwtracing/coresight/coresight-etm3x-core.c
@@ -895,6 +895,23 @@ static int etm_probe(struct amba_device *adev, const struct amba_id *id)
return ret;
}
+static int __exit etm_remove(struct amba_device *adev)
+{
+ struct etm_drvdata *drvdata = dev_get_drvdata(&adev->dev);
+
+ etm_perf_symlink(drvdata->csdev, false);
+
+ if (--etm_count == 0) {
+ cpuhp_remove_state_nocalls(CPUHP_AP_ARM_CORESIGHT_STARTING);
+ if (hp_online)
+ cpuhp_remove_state_nocalls(hp_online);
+ }
+
+ coresight_unregister(drvdata->csdev);
+
+ return 0;
+}
+

Don't we need to fix the races like we did for ETMv4 ?

Suzuki