From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Return-Path: MIME-Version: 1.0 In-Reply-To: <1520274579-30492-1-git-send-email-fkan@apm.com> References: <1520274579-30492-1-git-send-email-fkan@apm.com> From: Feng Kan Date: Thu, 15 Mar 2018 11:41:33 -0700 Message-ID: Subject: Re: [PATCH V3] PM / core: fix deferred probe breaking suspend resume order To: "Rafael J. Wysocki" , Linux PM , Lorenzo Pieralisi , linux-arm-kernel@lists.infradead.org, Linux PCI , Bjorn Helgaas , Greg Kroah-Hartman List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Feng Kan , Toan Le Content-Type: text/plain; charset="us-ascii" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+bjorn=helgaas.com@lists.infradead.org List-ID: On Mon, Mar 5, 2018 at 10:29 AM, Feng Kan wrote: > When bridge and its endpoint is enumerated the devices are added to the > dpm list. Afterward, the bridge defers probe when IOMMU is not ready. > This causes the bridge to be moved to the end of the dpm list when > deferred probe kicks in. The order of the dpm list for bridge and > endpoint is reversed. > > Add reordering code to move the bridge and its children and consumers to > the end of the pm list so the order for suspend and resume is not altered. > The code also move device and its children and consumers to the tail of > device_kset list if it is registered. > > Signed-off-by: Feng Kan > Signed-off-by: Toan Le > --- > V3: > 1. additional code comment changes > V2: > 1. change patch title from "move device and its children..." > 2. move define based on Bjorn's comment > 3. rename function name and comment content > > drivers/base/base.h | 3 +++ > drivers/base/core.c | 20 ++++++++++++++++++++ > drivers/base/dd.c | 4 +--- > 3 files changed, 24 insertions(+), 3 deletions(-) > > diff --git a/drivers/base/base.h b/drivers/base/base.h > index d800de6..a75c302 100644 > --- a/drivers/base/base.h > +++ b/drivers/base/base.h > @@ -161,3 +161,6 @@ static inline void module_remove_driver(struct device_driver *drv) { } > extern void device_links_no_driver(struct device *dev); > extern bool device_links_busy(struct device *dev); > extern void device_links_unbind_consumers(struct device *dev); > + > +/* device pm support */ > +void device_pm_move_to_tail(struct device *dev); > diff --git a/drivers/base/core.c b/drivers/base/core.c > index 110230d..3b37906 100644 > --- a/drivers/base/core.c > +++ b/drivers/base/core.c > @@ -148,6 +148,26 @@ static int device_reorder_to_tail(struct device *dev, void *not_used) > } > > /** > + * device_pm_move_to_tail - Move set of devices to the end of device lists > + * @dev: current device pointer > + * > + * This is a device_reorder_to_tail() wrapper taking the requisite locks. > + * > + * It moves the device along with all of its children and all of its consumers > + * to the ends of the device_kset and dpm_list, recursively. > + */ > +void device_pm_move_to_tail(struct device *dev) > +{ > + int idx; > + > + idx = device_links_read_lock(); > + device_pm_lock(); > + device_reorder_to_tail(dev, NULL); > + device_pm_unlock(); > + device_links_read_unlock(idx); > +} > + > +/** > * device_link_add - Create a link between two devices. > * @consumer: Consumer end of the link. > * @supplier: Supplier end of the link. > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > index 2c964f5..96fab29 100644 > --- a/drivers/base/dd.c > +++ b/drivers/base/dd.c > @@ -123,9 +123,7 @@ static void deferred_probe_work_func(struct work_struct *work) > * the list is a good order for suspend but deferred > * probe makes that very unsafe. > */ > - device_pm_lock(); > - device_pm_move_last(dev); > - device_pm_unlock(); > + device_pm_move_to_tail(dev); > > dev_dbg(dev, "Retrying from deferred list\n"); > if (initcall_debug && !initcalls_done) > -- > 1.8.3.1 > Hi, just wanted to check if there is anything else I need to change on this. Thanks. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel