From patchwork Wed Apr 13 06:01:49 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12811525 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id ED37E23CA for ; Wed, 13 Apr 2022 06:01:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1649829710; x=1681365710; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=vtmksge+PxxfmYNS5fXJl4pdxkZNhem2rCAEcMLmAY4=; b=Vvwh2z/57j12jkG1xB+kE4A4e2EmyYGCCN71jGIHyb/ppnGDbDIPnEdc azX681coxCjVgI3bY5c7vN+IRiHL5ZDpFhdI8IUzervTbDZvwY992YpLd /GVlsMXt78vKw8PFh91g8sL5sMLCOGsdsJtANVDUR8T00nueWhPsnlLIF WqP3zgTRylq/380wy1xpbaaS4uizjF3aK7ZQVXjW2FnwfEfpcCGFS6K9z qpsvKmHo67+nVaxUprYT8FeSQMPvuJfbp9EW7e3izgVFfSRz6O9SWBzQz dWyv553exCTva8swb1eBEZZmemrAmyURQyHC83gsR+BsIxUrvPNSG2ajJ g==; X-IronPort-AV: E=McAfee;i="6400,9594,10315"; a="287608119" X-IronPort-AV: E=Sophos;i="5.90,255,1643702400"; d="scan'208";a="287608119" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Apr 2022 23:01:50 -0700 X-IronPort-AV: E=Sophos;i="5.90,255,1643702400"; d="scan'208";a="645039160" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Apr 2022 23:01:50 -0700 Subject: [PATCH v2 04/12] cxl/core: Remove cxl_device_lock() From: Dan Williams To: linux-cxl@vger.kernel.org Cc: Alison Schofield , Vishal Verma , Ira Weiny , Ben Widawsky , Jonathan Cameron , Dave Jiang , Kevin Tian , peterz@infradead.org, gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, nvdimm@lists.linux.dev Date: Tue, 12 Apr 2022 23:01:49 -0700 Message-ID: <164982970986.684294.11190977495722089239.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <164982968798.684294.15817853329823976469.stgit@dwillia2-desk3.amr.corp.intel.com> References: <164982968798.684294.15817853329823976469.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 In preparation for moving lockdep_mutex nested lock acquisition into the core, remove the cxl_device_lock() wrapper, but preserve cxl_lock_class() that will be used to inform the core of the subsystem's lock ordering rules. Note that this reverts back to the default state of unvalidated device_lock(). A follow-on change to use the new dev->lock_class facility re-enables lockdep validation. Cc: Alison Schofield Cc: Vishal Verma Cc: Ira Weiny Cc: Ben Widawsky Reviewed-by: Jonathan Cameron Reviewed-by: Dave Jiang Reviewed-by: Kevin Tian Signed-off-by: Dan Williams --- drivers/cxl/core/pmem.c | 4 ++- drivers/cxl/core/port.c | 54 ++++++++++++++++++++--------------------------- drivers/cxl/cxl.h | 46 ---------------------------------------- drivers/cxl/mem.c | 4 ++- drivers/cxl/pmem.c | 12 +++++----- lib/Kconfig.debug | 2 +- 6 files changed, 34 insertions(+), 88 deletions(-) diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c index 8de240c4d96b..60f71caa5dbd 100644 --- a/drivers/cxl/core/pmem.c +++ b/drivers/cxl/core/pmem.c @@ -121,10 +121,10 @@ static void unregister_nvb(void *_cxl_nvb) * work to flush. Once the state has been changed to 'dead' then no new * work can be queued by user-triggered bind. */ - cxl_device_lock(&cxl_nvb->dev); + device_lock(&cxl_nvb->dev); flush = cxl_nvb->state != CXL_NVB_NEW; cxl_nvb->state = CXL_NVB_DEAD; - cxl_device_unlock(&cxl_nvb->dev); + device_unlock(&cxl_nvb->dev); /* * Even though the device core will trigger device_release_driver() diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 2ab1ba4499b3..437e8a71e5dc 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -312,10 +312,10 @@ static void cxl_port_release(struct device *dev) struct cxl_port *port = to_cxl_port(dev); struct cxl_ep *ep, *_e; - cxl_device_lock(dev); + device_lock(dev); list_for_each_entry_safe(ep, _e, &port->endpoints, list) cxl_ep_release(ep); - cxl_device_unlock(dev); + device_unlock(dev); ida_free(&cxl_port_ida, port->id); kfree(port); } @@ -554,7 +554,7 @@ static int match_root_child(struct device *dev, const void *match) return 0; port = to_cxl_port(dev); - cxl_device_lock(dev); + device_lock(dev); list_for_each_entry(dport, &port->dports, list) { iter = match; while (iter) { @@ -564,7 +564,7 @@ static int match_root_child(struct device *dev, const void *match) } } out: - cxl_device_unlock(dev); + device_unlock(dev); return !!iter; } @@ -623,13 +623,13 @@ static int add_dport(struct cxl_port *port, struct cxl_dport *new) static void cond_cxl_root_lock(struct cxl_port *port) { if (is_cxl_root(port)) - cxl_device_lock(&port->dev); + device_lock(&port->dev); } static void cond_cxl_root_unlock(struct cxl_port *port) { if (is_cxl_root(port)) - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); } static void cxl_dport_remove(void *data) @@ -736,15 +736,15 @@ static int add_ep(struct cxl_port *port, struct cxl_ep *new) { struct cxl_ep *dup; - cxl_device_lock(&port->dev); + device_lock(&port->dev); if (port->dead) { - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); return -ENXIO; } dup = find_ep(port, new->ep); if (!dup) list_add_tail(&new->list, &port->endpoints); - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); return dup ? -EEXIST : 0; } @@ -854,12 +854,12 @@ static void delete_endpoint(void *data) goto out; parent = &parent_port->dev; - cxl_device_lock(parent); + device_lock(parent); if (parent->driver && endpoint->uport) { devm_release_action(parent, cxl_unlink_uport, endpoint); devm_release_action(parent, unregister_port, endpoint); } - cxl_device_unlock(parent); + device_unlock(parent); put_device(parent); out: put_device(&endpoint->dev); @@ -920,7 +920,7 @@ static void cxl_detach_ep(void *data) } parent_port = to_cxl_port(port->dev.parent); - cxl_device_lock(&parent_port->dev); + device_lock(&parent_port->dev); if (!parent_port->dev.driver) { /* * The bottom-up race to delete the port lost to a @@ -928,12 +928,12 @@ static void cxl_detach_ep(void *data) * parent_port ->remove() will have cleaned up all * descendants. */ - cxl_device_unlock(&parent_port->dev); + device_unlock(&parent_port->dev); put_device(&port->dev); continue; } - cxl_device_lock(&port->dev); + device_lock(&port->dev); ep = find_ep(port, &cxlmd->dev); dev_dbg(&cxlmd->dev, "disconnect %s from %s\n", ep ? dev_name(ep->ep) : "", dev_name(&port->dev)); @@ -948,7 +948,7 @@ static void cxl_detach_ep(void *data) port->dead = true; list_splice_init(&port->dports, &reap_dports); } - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); if (!list_empty(&reap_dports)) { dev_dbg(&cxlmd->dev, "delete %s\n", @@ -956,7 +956,7 @@ static void cxl_detach_ep(void *data) delete_switch_port(port, &reap_dports); } put_device(&port->dev); - cxl_device_unlock(&parent_port->dev); + device_unlock(&parent_port->dev); } } @@ -1004,7 +1004,7 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, return -EAGAIN; } - cxl_device_lock(&parent_port->dev); + device_lock(&parent_port->dev); if (!parent_port->dev.driver) { dev_warn(&cxlmd->dev, "port %s:%s disabled, failed to enumerate CXL.mem\n", @@ -1022,7 +1022,7 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, get_device(&port->dev); } out: - cxl_device_unlock(&parent_port->dev); + device_unlock(&parent_port->dev); if (IS_ERR(port)) rc = PTR_ERR(port); @@ -1133,14 +1133,14 @@ struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port, { struct cxl_dport *dport; - cxl_device_lock(&port->dev); + device_lock(&port->dev); list_for_each_entry(dport, &port->dports, list) if (dport->dport == dev) { - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); return dport; } - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); return NULL; } EXPORT_SYMBOL_NS_GPL(cxl_find_dport_by_dev, CXL); @@ -1379,9 +1379,9 @@ int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map) port = to_cxl_port(cxld->dev.parent); - cxl_device_lock(&port->dev); + device_lock(&port->dev); rc = cxl_decoder_add_locked(cxld, target_map); - cxl_device_unlock(&port->dev); + device_unlock(&port->dev); return rc; } @@ -1452,13 +1452,7 @@ static int cxl_bus_probe(struct device *dev) { int rc; - /* - * Take the CXL nested lock since the driver core only holds - * @dev->mutex and not @dev->lockdep_mutex. - */ - cxl_nested_lock(dev); rc = to_cxl_drv(dev->driver)->probe(dev); - cxl_nested_unlock(dev); dev_dbg(dev, "probe: %d\n", rc); return rc; @@ -1468,10 +1462,8 @@ static void cxl_bus_remove(struct device *dev) { struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver); - cxl_nested_lock(dev); if (cxl_drv->remove) cxl_drv->remove(dev); - cxl_nested_unlock(dev); } static struct workqueue_struct *cxl_bus_wq; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index c9fda9304c54..a6c1a027e389 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -439,51 +439,5 @@ static inline int cxl_lock_class(struct device *dev) else return CXL_ANON_LOCK; } - -static inline void cxl_nested_lock(struct device *dev) -{ - mutex_lock_nested(&dev->lockdep_mutex, cxl_lock_class(dev)); -} - -static inline void cxl_nested_unlock(struct device *dev) -{ - mutex_unlock(&dev->lockdep_mutex); -} - -static inline void cxl_device_lock(struct device *dev) -{ - /* - * For double lock errors the lockup will happen before lockdep - * warns at cxl_nested_lock(), so assert explicitly. - */ - lockdep_assert_not_held(&dev->lockdep_mutex); - - device_lock(dev); - cxl_nested_lock(dev); -} - -static inline void cxl_device_unlock(struct device *dev) -{ - cxl_nested_unlock(dev); - device_unlock(dev); -} -#else -static inline void cxl_nested_lock(struct device *dev) -{ -} - -static inline void cxl_nested_unlock(struct device *dev) -{ -} - -static inline void cxl_device_lock(struct device *dev) -{ - device_lock(dev); -} - -static inline void cxl_device_unlock(struct device *dev) -{ - device_unlock(dev); -} #endif #endif /* __CXL_H__ */ diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 49a4b1c47299..91fb8d5b21a7 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -195,7 +195,7 @@ static int cxl_mem_probe(struct device *dev) return -ENXIO; } - cxl_device_lock(&parent_port->dev); + device_lock(&parent_port->dev); if (!parent_port->dev.driver) { dev_err(dev, "CXL port topology %s not enabled\n", dev_name(&parent_port->dev)); @@ -205,7 +205,7 @@ static int cxl_mem_probe(struct device *dev) rc = create_endpoint(cxlmd, parent_port); out: - cxl_device_unlock(&parent_port->dev); + device_unlock(&parent_port->dev); put_device(&parent_port->dev); return rc; } diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c index 15ad666ab03e..b65a272a2d6d 100644 --- a/drivers/cxl/pmem.c +++ b/drivers/cxl/pmem.c @@ -43,7 +43,7 @@ static int cxl_nvdimm_probe(struct device *dev) if (!cxl_nvb) return -ENXIO; - cxl_device_lock(&cxl_nvb->dev); + device_lock(&cxl_nvb->dev); if (!cxl_nvb->nvdimm_bus) { rc = -ENXIO; goto out; @@ -68,7 +68,7 @@ static int cxl_nvdimm_probe(struct device *dev) dev_set_drvdata(dev, nvdimm); rc = devm_add_action_or_reset(dev, unregister_nvdimm, nvdimm); out: - cxl_device_unlock(&cxl_nvb->dev); + device_unlock(&cxl_nvb->dev); put_device(&cxl_nvb->dev); return rc; @@ -233,7 +233,7 @@ static void cxl_nvb_update_state(struct work_struct *work) struct nvdimm_bus *victim_bus = NULL; bool release = false, rescan = false; - cxl_device_lock(&cxl_nvb->dev); + device_lock(&cxl_nvb->dev); switch (cxl_nvb->state) { case CXL_NVB_ONLINE: if (!online_nvdimm_bus(cxl_nvb)) { @@ -251,7 +251,7 @@ static void cxl_nvb_update_state(struct work_struct *work) default: break; } - cxl_device_unlock(&cxl_nvb->dev); + device_unlock(&cxl_nvb->dev); if (release) device_release_driver(&cxl_nvb->dev); @@ -327,9 +327,9 @@ static int cxl_nvdimm_bridge_reset(struct device *dev, void *data) return 0; cxl_nvb = to_cxl_nvdimm_bridge(dev); - cxl_device_lock(dev); + device_lock(dev); cxl_nvb->state = CXL_NVB_NEW; - cxl_device_unlock(dev); + device_unlock(dev); return 0; } diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 075cd25363ac..333d41da7621 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -1563,7 +1563,7 @@ config PROVE_CXL_LOCKING bool "CXL" depends on CXL_BUS help - Enable lockdep to validate cxl_device_lock() usage. + Enable lockdep to validate CXL subsystem usage of the device lock. endchoice