Re: [PATCH v7 10/25] coresight: etm4x: allow etm4x to be built as a module
From: Suzuki K Poulose <suzuki.poulose@arm.com>
Date: 2020-08-05 11:24:12
On 08/05/2020 03:54 AM, Tingwei Zhang wrote:
From: Kim Phillips <redacted> Allow to build coresight-etm4x 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-etm4x by the Makefile - add an etm4_remove function, for module unload - add a MODULE_DEVICE_TABLE for autoloading on boot Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Leo Yan <redacted> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Russell King <linux@armlinux.org.uk> Signed-off-by: Kim Phillips <redacted> Signed-off-by: Tingwei Zhang <redacted> Tested-by: Mike Leach <redacted> ---
+static int __exit etm4_remove(struct amba_device *adev)
+{
+ struct etmv4_drvdata *drvdata = dev_get_drvdata(&adev->dev);
+
+ etm_perf_symlink(drvdata->csdev, false);
+
+ etmdrvdata[drvdata->cpu] = NULL;I think we need to explicitly make this change visible to the other observers, to make sure that a PM notifier doesn't end up using the stale per-cpu pointer.
quoted hunk ↗ jump to hunk
+ etm4_pm_clear(); + + coresight_unregister(drvdata->csdev); + + return 0; +} + + static const struct amba_id etm4_ids[] = { CS_AMBA_ID(0x000bb95d), /* Cortex-A53 */ CS_AMBA_ID(0x000bb95e), /* Cortex-A57 */@@ -1590,12 +1605,21 @@ static const struct amba_id etm4_ids[] = { {}, }; +MODULE_DEVICE_TABLE(amba, etm4_ids); + static struct amba_driver etm4x_driver = { .drv = { .name = "coresight-etm4x", + .owner = THIS_MODULE, .suppress_bind_attrs = true, }, .probe = etm4_probe, + .remove = etm4_remove, .id_table = etm4_ids, }; -builtin_amba_driver(etm4x_driver); +module_amba_driver(etm4x_driver);
Please note that this could conflict with the following patch : https://lkml.kernel.org/r/20200729051310.18436-1-saiprakash.ranjan@codeaurora.org Otherwise looks good to me. Suzuki _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel