From patchwork Fri Aug 30 01:31:36 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Li, Ming4" X-Patchwork-Id: 13784110 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) (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 B748428EC for ; Fri, 30 Aug 2024 02:01:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.175.65.9 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724983308; cv=none; b=QS23osrHqCYHzG1XVyrL40UDR0THgCWiiKZz7+7vdlXjK5Q8XVVI2LSHCNMKjPZh/6agFIzp91hGGN7TQJjm0MW8O0xOcLBTU285SNhzcarSwi2FQVG6T/dT7wcW2k6ZlFc5oUb1MGV3KA4P0pQASz4MvdfVFtvnwRdjf4BjosA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724983308; c=relaxed/simple; bh=zdCz3oy2OQmXxcxEMKbrgBfhEDXAElWP8tJ4bJAmWio=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=midEamhagRd6owyVWM88qaP672UjuKRYrI7feAodcST8LRNdpmF+MOm+CKgoxyl4fm88LuwhH39SY2V8nQdGmR5+tzxLtv/vQKsWiE0LoF0okU/ZWXXg8e5vuYering50RmcvASLsaVWKsQeAG8NrWXZNEtQyPQu9f5fO/imeeo= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=NViEIU8F; arc=none smtp.client-ip=198.175.65.9 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="NViEIU8F" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1724983306; x=1756519306; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=zdCz3oy2OQmXxcxEMKbrgBfhEDXAElWP8tJ4bJAmWio=; b=NViEIU8F8jL2y3VT/I8XK5f59bAyQOcPLlNIWKBUOGe4yGsr79my2kDL hf1gkk8/t9gC/2a26wKdE3sMJXcLimM2XKXxix04BCm7K4QOTuviBnOgM P8OQMNVzuIreWUlONw1vmlP6dNGPtPVs4MxxTAlFuGWkMAPyQ01vD8Omy 7CGBqt2ZaCq69bkxbi92FnKA5me/i+PeqRtmzN4jbHIvnVtwzvlnJEhSz p+7x0if8Zx48Th0LC8ESqSBQVcEd/tEiLGg7Gf3x9DxICs94tDi4FrljE ZAwmF9TnICy14Ggtz9FJtm28o1IkCF1FnjKI7A2p82etTc/CClgOffPpQ Q==; X-CSE-ConnectionGUID: 4dOwM5DlRLyyT5kybOyDUg== X-CSE-MsgGUID: 2dZOTuUpSMSedV0jp4mfkQ== X-IronPort-AV: E=McAfee;i="6700,10204,11179"; a="46122214" X-IronPort-AV: E=Sophos;i="6.10,187,1719903600"; d="scan'208";a="46122214" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Aug 2024 19:01:45 -0700 X-CSE-ConnectionGUID: loqFmbKIRVaPXL4J4NEiCA== X-CSE-MsgGUID: UubSgMV2TT++p5X4Xfo/Og== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.10,187,1719903600"; d="scan'208";a="101267082" Received: from s2600wttr.bj.intel.com ([10.240.192.138]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Aug 2024 19:01:43 -0700 From: Li Ming To: dave@stgolabs.net, jonathan.cameron@huawei.com, dave.jiang@intel.com, alison.schofield@intel.com, vishal.l.verma@intel.com, ira.weiny@intel.com, dan.j.williams@intel.com Cc: linux-cxl@vger.kernel.org, Li Ming Subject: [PATCH v3 1/3] cxl/port: Use __free() to drop put_device() for cxl_port Date: Fri, 30 Aug 2024 01:31:36 +0000 Message-Id: <20240830013138.2256244-1-ming4.li@intel.com> X-Mailer: git-send-email 2.40.1 Precedence: bulk X-Mailing-List: linux-cxl@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Using scope-based resource management __free() marco with a new helper called put_cxl_port() to drop open coded the put_device() used to dereference the 'struct device' in cxl_port. Suggested-by: Dan Williams Signed-off-by: Li Ming Reviewed-by: Jonathan Cameron --- v3: - Jonathan: Keep the dereference sequence between port and parent port. - Jonathan: Adjust the changelog of the patch 3. Link to v2: https://lore.kernel.org/linux-cxl/0a815412-cd86-4d08-b93f-4ff4d88134c6@intel.com/T/#m49c20d7834114878c2e4ad03a55da8d4999caa59 v2: - Use guard() instead of scoped_guard() in some cases. - Ira: Check the return value of find_cxl_port_at(). Link to v1: https://lore.kernel.org/linux-cxl/8ac82c61-7871-4914-b376-32431868622c@intel.com/T/#m07695675435bf702311dfc40f64289b9623afa16 --- drivers/cxl/core/pci.c | 6 ++---- drivers/cxl/core/port.c | 30 +++++++++++++----------------- drivers/cxl/cxl.h | 1 + drivers/cxl/mem.c | 5 ++--- drivers/cxl/pci.c | 7 ++----- 5 files changed, 20 insertions(+), 29 deletions(-) diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 51132a575b27..4725e37d90fb 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -915,15 +915,13 @@ static void cxl_handle_rdport_errors(struct cxl_dev_state *cxlds) struct pci_dev *pdev = to_pci_dev(cxlds->dev); struct aer_capability_regs aer_regs; struct cxl_dport *dport; - struct cxl_port *port; int severity; - port = cxl_pci_find_port(pdev, &dport); + struct cxl_port *port __free(put_cxl_port) = + cxl_pci_find_port(pdev, &dport); if (!port) return; - put_device(&port->dev); - if (!cxl_rch_get_aer_info(dport->regs.dport_aer, &aer_regs)) return; diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index 1d5007e3795a..ffd322aaed42 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -1477,12 +1477,11 @@ static void cxl_detach_ep(void *data) .cxlmd = cxlmd, .depth = i, }; - struct device *dev; struct cxl_ep *ep; bool died = false; - dev = bus_find_device(&cxl_bus_type, NULL, &ctx, - port_has_memdev); + struct device *dev __free(put_device) = + bus_find_device(&cxl_bus_type, NULL, &ctx, port_has_memdev); if (!dev) continue; port = to_cxl_port(dev); @@ -1512,7 +1511,6 @@ static void cxl_detach_ep(void *data) dev_name(&port->dev)); delete_switch_port(port); } - put_device(&port->dev); device_unlock(&parent_port->dev); } } @@ -1540,7 +1538,6 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, struct device *dport_dev) { struct device *dparent = grandparent(dport_dev); - struct cxl_port *port, *parent_port = NULL; struct cxl_dport *dport, *parent_dport; resource_size_t component_reg_phys; int rc; @@ -1556,12 +1553,18 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, return -ENXIO; } - parent_port = find_cxl_port(dparent, &parent_dport); + struct cxl_port *parent_port __free(put_cxl_port) = + find_cxl_port(dparent, &parent_dport); if (!parent_port) { /* iterate to create this parent_port */ return -EAGAIN; } + /* + * Definition with __free() here to keep the sequence of + * dereferencing the device of the port before the parent_port releasing. + */ + struct cxl_port *port __free(put_cxl_port) = NULL; device_lock(&parent_port->dev); if (!parent_port->dev.driver) { dev_warn(&cxlmd->dev, @@ -1596,10 +1599,8 @@ static int add_port_attach_ep(struct cxl_memdev *cxlmd, */ rc = -ENXIO; } - put_device(&port->dev); } - put_device(&parent_port->dev); return rc; } @@ -1630,7 +1631,6 @@ int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) struct device *dport_dev = grandparent(iter); struct device *uport_dev; struct cxl_dport *dport; - struct cxl_port *port; /* * The terminal "grandparent" in PCI is NULL and @platform_bus @@ -1649,7 +1649,8 @@ int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) dev_dbg(dev, "scan: iter: %s dport_dev: %s parent: %s\n", dev_name(iter), dev_name(dport_dev), dev_name(uport_dev)); - port = find_cxl_port(dport_dev, &dport); + struct cxl_port *port __free(put_cxl_port) = + find_cxl_port(dport_dev, &dport); if (port) { dev_dbg(&cxlmd->dev, "found already registered port %s:%s\n", @@ -1664,18 +1665,13 @@ int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) * the parent_port lock as the current port may be being * reaped. */ - if (rc && rc != -EBUSY) { - put_device(&port->dev); + if (rc && rc != -EBUSY) return rc; - } /* Any more ports to add between this one and the root? */ - if (!dev_is_cxl_root_child(&port->dev)) { - put_device(&port->dev); + if (!dev_is_cxl_root_child(&port->dev)) continue; - } - put_device(&port->dev); return 0; } diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 9afb407d438f..84cf3b4d60a1 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -744,6 +744,7 @@ struct cxl_root *find_cxl_root(struct cxl_port *port); void put_cxl_root(struct cxl_root *cxl_root); DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_cxl_root(_T)) +DEFINE_FREE(put_cxl_port, struct cxl_port *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev)) int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd); void cxl_bus_rescan(void); void cxl_bus_drain(void); diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 7de232eaeb17..ab9b8ab8df44 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -109,7 +109,6 @@ static int cxl_mem_probe(struct device *dev) struct cxl_memdev_state *mds = to_cxl_memdev_state(cxlmd->cxlds); struct cxl_dev_state *cxlds = cxlmd->cxlds; struct device *endpoint_parent; - struct cxl_port *parent_port; struct cxl_dport *dport; struct dentry *dentry; int rc; @@ -146,7 +145,8 @@ static int cxl_mem_probe(struct device *dev) if (rc) return rc; - parent_port = cxl_mem_find_port(cxlmd, &dport); + struct cxl_port *parent_port __free(put_cxl_port) = + cxl_mem_find_port(cxlmd, &dport); if (!parent_port) { dev_err(dev, "CXL port topology not found\n"); return -ENXIO; @@ -179,7 +179,6 @@ static int cxl_mem_probe(struct device *dev) rc = devm_cxl_add_endpoint(endpoint_parent, cxlmd, dport); unlock: device_unlock(endpoint_parent); - put_device(&parent_port->dev); if (rc) return rc; diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 4be35dc22202..26e75499abdd 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -473,7 +473,6 @@ static bool is_cxl_restricted(struct pci_dev *pdev) static int cxl_rcrb_get_comp_regs(struct pci_dev *pdev, struct cxl_register_map *map) { - struct cxl_port *port; struct cxl_dport *dport; resource_size_t component_reg_phys; @@ -482,14 +481,12 @@ static int cxl_rcrb_get_comp_regs(struct pci_dev *pdev, .resource = CXL_RESOURCE_NONE, }; - port = cxl_pci_find_port(pdev, &dport); + struct cxl_port *port __free(put_cxl_port) = + cxl_pci_find_port(pdev, &dport); if (!port) return -EPROBE_DEFER; component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport); - - put_device(&port->dev); - if (component_reg_phys == CXL_RESOURCE_NONE) return -ENXIO;