Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64D5EC64EC4 for ; Wed, 8 Mar 2023 17:40:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229937AbjCHRkf (ORCPT ); Wed, 8 Mar 2023 12:40:35 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229906AbjCHRkJ (ORCPT ); Wed, 8 Mar 2023 12:40:09 -0500 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 172D8CDA05 for ; Wed, 8 Mar 2023 09:39:41 -0800 (PST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 4DE1B106F; Wed, 8 Mar 2023 09:40:23 -0800 (PST) Received: from e127643.arm.com (unknown [10.57.48.148]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 510943F67D; Wed, 8 Mar 2023 09:39:38 -0800 (PST) From: James Clark To: coresight@lists.linaro.org Cc: James Clark , Mathieu Poirier , Suzuki K Poulose , Mike Leach , Leo Yan , Alexander Shishkin , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH 8/8] coresight: Fix CTI module refcount leak by making it a helper device Date: Wed, 8 Mar 2023 17:39:02 +0000 Message-Id: <20230308173904.3449231-9-james.clark@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230308173904.3449231-1-james.clark@arm.com> References: <20230308173904.3449231-1-james.clark@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The CTI module has some hard coded refcounting code that has a leak. For example running perf and then trying to unload it fails: perf record -e cs_etm// -a -- ls rmmod coresight_cti rmmod: ERROR: Module coresight_cti is in use The coresight core already handles references of devices in use, so by making CTI a normal helper device, we get working refcounting for free. Signed-off-by: James Clark --- drivers/hwtracing/coresight/coresight-core.c | 73 +++---------------- .../hwtracing/coresight/coresight-cti-core.c | 56 +++++++++----- .../hwtracing/coresight/coresight-cti-sysfs.c | 4 +- drivers/hwtracing/coresight/coresight-cti.h | 4 +- include/linux/coresight.h | 28 +------ 5 files changed, 53 insertions(+), 112 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c index 7554307f0d88..07bcb972fe15 100644 --- a/drivers/hwtracing/coresight/coresight-core.c +++ b/drivers/hwtracing/coresight/coresight-core.c @@ -253,48 +253,6 @@ void coresight_disclaim_device(struct coresight_device *csdev) } EXPORT_SYMBOL_GPL(coresight_disclaim_device); -/* enable or disable an associated CTI device of the supplied CS device */ -static int -coresight_control_assoc_ectdev(struct coresight_device *csdev, bool enable) -{ - int ect_ret = 0; - struct coresight_device *ect_csdev = csdev->ect_dev; - struct module *mod; - - if (!ect_csdev) - return 0; - if ((!ect_ops(ect_csdev)->enable) || (!ect_ops(ect_csdev)->disable)) - return 0; - - mod = ect_csdev->dev.parent->driver->owner; - if (enable) { - if (try_module_get(mod)) { - ect_ret = ect_ops(ect_csdev)->enable(ect_csdev); - if (ect_ret) { - module_put(mod); - } else { - get_device(ect_csdev->dev.parent); - csdev->ect_enabled = true; - } - } else - ect_ret = -ENODEV; - } else { - if (csdev->ect_enabled) { - ect_ret = ect_ops(ect_csdev)->disable(ect_csdev); - put_device(ect_csdev->dev.parent); - module_put(mod); - csdev->ect_enabled = false; - } - } - - /* output warning if ECT enable is preventing trace operation */ - if (ect_ret) - dev_info(&csdev->dev, "Associated ECT device (%s) %s failed\n", - dev_name(&ect_csdev->dev), - enable ? "enable" : "disable"); - return ect_ret; -} - /* * Set the associated ect / cti device while holding the coresight_mutex * to avoid a race with coresight_enable that may try to use this value. @@ -302,8 +260,14 @@ coresight_control_assoc_ectdev(struct coresight_device *csdev, bool enable) void coresight_set_assoc_ectdev_mutex(struct coresight_device *csdev, struct coresight_device *ect_csdev) { + struct coresight_connection conn = {}; + mutex_lock(&coresight_mutex); - csdev->ect_dev = ect_csdev; + conn.child_fwnode = fwnode_handle_get(dev_fwnode(&ect_csdev->dev)); + conn.child_dev = ect_csdev; + conn.child_port = conn.outport = -1; + coresight_add_conn(csdev->dev.parent, csdev->pdata, &conn); + coresight_fixup_inputs(csdev); mutex_unlock(&coresight_mutex); } EXPORT_SYMBOL_GPL(coresight_set_assoc_ectdev_mutex); @@ -320,12 +284,8 @@ static int coresight_enable_sink(struct coresight_device *csdev, if (!sink_ops(csdev)->enable) return -EINVAL; - ret = coresight_control_assoc_ectdev(csdev, true); - if (ret) - return ret; ret = sink_ops(csdev)->enable(csdev, mode, data); if (ret) { - coresight_control_assoc_ectdev(csdev, false); return ret; } csdev->enable = true; @@ -343,7 +303,6 @@ static void coresight_disable_sink(struct coresight_device *csdev) ret = sink_ops(csdev)->disable(csdev); if (ret) return; - coresight_control_assoc_ectdev(csdev, false); csdev->enable = false; } @@ -368,17 +327,11 @@ static int coresight_enable_link(struct coresight_device *csdev, return outport; if (link_ops(csdev)->enable) { - ret = coresight_control_assoc_ectdev(csdev, true); - if (!ret) { - ret = link_ops(csdev)->enable(csdev, inport, outport); - if (ret) - coresight_control_assoc_ectdev(csdev, false); - } + ret = link_ops(csdev)->enable(csdev, inport, outport); + if (!ret) + csdev->enable = true; } - if (!ret) - csdev->enable = true; - return ret; } @@ -407,7 +360,6 @@ static void coresight_disable_link(struct coresight_device *csdev, if (link_ops(csdev)->disable) { link_ops(csdev)->disable(csdev, inport, outport); - coresight_control_assoc_ectdev(csdev, false); } for (i = 0; i < nr_conns; i++) @@ -424,12 +376,8 @@ static int coresight_enable_source(struct coresight_device *csdev, if (!csdev->enable) { if (source_ops(csdev)->enable) { - ret = coresight_control_assoc_ectdev(csdev, true); - if (ret) - return ret; ret = source_ops(csdev)->enable(csdev, NULL, mode); if (ret) { - coresight_control_assoc_ectdev(csdev, false); return ret; } } @@ -482,7 +430,6 @@ static bool coresight_disable_source(struct coresight_device *csdev) if (atomic_dec_return(csdev->refcnt) == 0) { if (source_ops(csdev)->disable) source_ops(csdev)->disable(csdev, NULL); - coresight_control_assoc_ectdev(csdev, false); csdev->enable = false; } return !csdev->enable; diff --git a/drivers/hwtracing/coresight/coresight-cti-core.c b/drivers/hwtracing/coresight/coresight-cti-core.c index 277c890a1f1f..3f3dfb528188 100644 --- a/drivers/hwtracing/coresight/coresight-cti-core.c +++ b/drivers/hwtracing/coresight/coresight-cti-core.c @@ -555,7 +555,10 @@ static void cti_add_assoc_to_csdev(struct coresight_device *csdev) mutex_lock(&ect_mutex); /* exit if current is an ECT device.*/ - if ((csdev->type == CORESIGHT_DEV_TYPE_ECT) || list_empty(&ect_net)) + if ((csdev->type == CORESIGHT_DEV_TYPE_HELPER && + csdev->subtype.helper_subtype == + CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI) || + list_empty(&ect_net)) goto cti_add_done; /* if we didn't find the csdev previously we used the fwnode name */ @@ -580,6 +583,22 @@ static void cti_add_assoc_to_csdev(struct coresight_device *csdev) mutex_unlock(&ect_mutex); } +struct coresight_device *cti__get_cti_device(struct coresight_device *csdev) +{ + int i; + struct coresight_device *tmp; + + for (i = 0; i < csdev->pdata->nr_outconns; i++) { + tmp = csdev->pdata->out_conns[i].child_dev; + + if (tmp && tmp->type == CORESIGHT_DEV_TYPE_HELPER && + tmp->subtype.helper_subtype == + CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI) + return tmp; + } + return NULL; +} + /* * Removing the associated devices is easier. * A CTI will not have a value for csdev->ect_dev. @@ -588,20 +607,21 @@ static void cti_remove_assoc_from_csdev(struct coresight_device *csdev) { struct cti_drvdata *ctidrv; struct cti_trig_con *tc; + struct coresight_device *cti_csdev = cti__get_cti_device(csdev); struct cti_device *ctidev; + if (!cti_csdev) + return; + mutex_lock(&ect_mutex); - if (csdev->ect_dev) { - ctidrv = csdev_to_cti_drvdata(csdev->ect_dev); - ctidev = &ctidrv->ctidev; - list_for_each_entry(tc, &ctidev->trig_cons, node) { - if (tc->con_dev == csdev) { - cti_remove_sysfs_link(ctidrv, tc); - tc->con_dev = NULL; - break; - } + ctidrv = csdev_to_cti_drvdata(cti_csdev); + ctidev = &ctidrv->ctidev; + list_for_each_entry(tc, &ctidev->trig_cons, node) { + if (tc->con_dev == csdev) { + cti_remove_sysfs_link(ctidrv, tc); + tc->con_dev = NULL; + break; } - csdev->ect_dev = NULL; } mutex_unlock(&ect_mutex); } @@ -646,8 +666,6 @@ static void cti_remove_conn_xrefs(struct cti_drvdata *drvdata) list_for_each_entry(tc, &ctidev->trig_cons, node) { if (tc->con_dev) { - coresight_set_assoc_ectdev_mutex(tc->con_dev, - NULL); cti_remove_sysfs_link(drvdata, tc); tc->con_dev = NULL; } @@ -795,27 +813,27 @@ static void cti_pm_release(struct cti_drvdata *drvdata) } /** cti ect operations **/ -int cti_enable(struct coresight_device *csdev) +int cti_enable(struct coresight_device *csdev, enum cs_mode mode, void *data) { struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev); return cti_enable_hw(drvdata); } -int cti_disable(struct coresight_device *csdev) +int cti_disable(struct coresight_device *csdev, void *data) { struct cti_drvdata *drvdata = csdev_to_cti_drvdata(csdev); return cti_disable_hw(drvdata); } -static const struct coresight_ops_ect cti_ops_ect = { +static const struct coresight_ops_helper cti_ops_ect = { .enable = cti_enable, .disable = cti_disable, }; static const struct coresight_ops cti_ops = { - .ect_ops = &cti_ops_ect, + .helper_ops = &cti_ops_ect, }; /* @@ -922,8 +940,8 @@ static int cti_probe(struct amba_device *adev, const struct amba_id *id) /* set up coresight component description */ cti_desc.pdata = pdata; - cti_desc.type = CORESIGHT_DEV_TYPE_ECT; - cti_desc.subtype.ect_subtype = CORESIGHT_DEV_SUBTYPE_ECT_CTI; + cti_desc.type = CORESIGHT_DEV_TYPE_HELPER; + cti_desc.subtype.helper_subtype = CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI; cti_desc.ops = &cti_ops; cti_desc.groups = drvdata->ctidev.con_groups; cti_desc.dev = dev; diff --git a/drivers/hwtracing/coresight/coresight-cti-sysfs.c b/drivers/hwtracing/coresight/coresight-cti-sysfs.c index e528cff9d4e2..d25dd2737b49 100644 --- a/drivers/hwtracing/coresight/coresight-cti-sysfs.c +++ b/drivers/hwtracing/coresight/coresight-cti-sysfs.c @@ -112,11 +112,11 @@ static ssize_t enable_store(struct device *dev, ret = pm_runtime_resume_and_get(dev->parent); if (ret) return ret; - ret = cti_enable(drvdata->csdev); + ret = cti_enable(drvdata->csdev, CS_MODE_SYSFS, NULL); if (ret) pm_runtime_put(dev->parent); } else { - ret = cti_disable(drvdata->csdev); + ret = cti_disable(drvdata->csdev, NULL); if (!ret) pm_runtime_put(dev->parent); } diff --git a/drivers/hwtracing/coresight/coresight-cti.h b/drivers/hwtracing/coresight/coresight-cti.h index 8b106b13a244..cb9ee616d01f 100644 --- a/drivers/hwtracing/coresight/coresight-cti.h +++ b/drivers/hwtracing/coresight/coresight-cti.h @@ -215,8 +215,8 @@ int cti_add_connection_entry(struct device *dev, struct cti_drvdata *drvdata, const char *assoc_dev_name); struct cti_trig_con *cti_allocate_trig_con(struct device *dev, int in_sigs, int out_sigs); -int cti_enable(struct coresight_device *csdev); -int cti_disable(struct coresight_device *csdev); +int cti_enable(struct coresight_device *csdev, enum cs_mode mode, void *data); +int cti_disable(struct coresight_device *csdev, void *data); void cti_write_all_hw_regs(struct cti_drvdata *drvdata); void cti_write_intack(struct device *dev, u32 ackval); void cti_write_single_reg(struct cti_drvdata *drvdata, int offset, u32 value); diff --git a/include/linux/coresight.h b/include/linux/coresight.h index d61b0d12542e..815e0776c1cb 100644 --- a/include/linux/coresight.h +++ b/include/linux/coresight.h @@ -40,8 +40,7 @@ enum coresight_dev_type { CORESIGHT_DEV_TYPE_LINK, CORESIGHT_DEV_TYPE_LINKSINK, CORESIGHT_DEV_TYPE_SOURCE, - CORESIGHT_DEV_TYPE_HELPER, - CORESIGHT_DEV_TYPE_ECT, + CORESIGHT_DEV_TYPE_HELPER }; enum coresight_dev_subtype_sink { @@ -66,12 +65,7 @@ enum coresight_dev_subtype_source { enum coresight_dev_subtype_helper { CORESIGHT_DEV_SUBTYPE_HELPER_CATU, -}; - -/* Embedded Cross Trigger (ECT) sub-types */ -enum coresight_dev_subtype_ect { - CORESIGHT_DEV_SUBTYPE_ECT_NONE, - CORESIGHT_DEV_SUBTYPE_ECT_CTI, + CORESIGHT_DEV_SUBTYPE_HELPER_ECT_CTI }; /** @@ -84,8 +78,6 @@ enum coresight_dev_subtype_ect { * by @coresight_dev_subtype_source. * @helper_subtype: type of helper this component is, as defined * by @coresight_dev_subtype_helper. - * @ect_subtype: type of cross trigger this component is, as - * defined by @coresight_dev_subtype_ect */ union coresight_dev_subtype { /* We have some devices which acts as LINK and SINK */ @@ -95,7 +87,6 @@ union coresight_dev_subtype { }; enum coresight_dev_subtype_source source_subtype; enum coresight_dev_subtype_helper helper_subtype; - enum coresight_dev_subtype_ect ect_subtype; }; /** @@ -261,12 +252,9 @@ struct coresight_device { bool activated; /* true only if a sink is part of a path */ struct dev_ext_attribute *ea; struct coresight_device *def_sink; - /* cross trigger handling */ - struct coresight_device *ect_dev; /* sysfs links between components */ int nr_links; bool has_conns_grp; - bool ect_enabled; /* true only if associated ect device is enabled */ /* system configuration and feature lists */ struct list_head feature_csdev_list; struct list_head config_csdev_list; @@ -374,23 +362,11 @@ struct coresight_ops_helper { int (*disable)(struct coresight_device *csdev, void *data); }; -/** - * struct coresight_ops_ect - Ops for an embedded cross trigger device - * - * @enable : Enable the device - * @disable : Disable the device - */ -struct coresight_ops_ect { - int (*enable)(struct coresight_device *csdev); - int (*disable)(struct coresight_device *csdev); -}; - struct coresight_ops { const struct coresight_ops_sink *sink_ops; const struct coresight_ops_link *link_ops; const struct coresight_ops_source *source_ops; const struct coresight_ops_helper *helper_ops; - const struct coresight_ops_ect *ect_ops; }; #if IS_ENABLED(CONFIG_CORESIGHT) -- 2.34.1