/* * v4l2-fh.h * * V4L2 file handle. Store per file handle data for the V4L2 * framework. Using file handles is optional for the drivers. * * Copyright (C) 2009--2010 Nokia Corporation. * * Contact: Sakari Ailus * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * version 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA * 02110-1301 USA */ #ifndef V4L2_FH_H #define V4L2_FH_H #include #include #include struct video_device; struct v4l2_ctrl_handler; /** * struct v4l2_fh - Describes a V4L2 file handler * * @list: list of file handlers * @vdev: pointer to &struct video_device * @ctrl_handler: pointer to &struct v4l2_ctrl_handler * @prio: priority of the file handler, as defined by &enum v4l2_priority * * @wait: event' s wait queue * @subscribed: list of subscribed events * @available: list of events waiting to be dequeued * @navailable: number of available events at @available list * @sequence: event sequence number * @m2m_ctx: pointer to &struct v4l2_m2m_ctx */ struct v4l2_fh { struct list_head list; struct video_device *vdev; struct v4l2_ctrl_handler *ctrl_handler; enum v4l2_priority prio; /* Events */ wait_queue_head_t wait; struct list_head subscribed; struct list_head available; unsigned int navailable; u32 sequence; #if IS_ENABLED(CONFIG_V4L2_MEM2MEM_DEV) struct v4l2_m2m_ctx *m2m_ctx; #endif }; /** * v4l2_fh_init - Initialise the file handle. * * @fh: pointer to &struct v4l2_fh * @vdev: pointer to &struct video_device * * Parts of the V4L2 framework using the * file handles should be initialised in this function. Must be called * from driver's v4l2_file_operations->open\(\) handler if the driver * uses &struct v4l2_fh. */ void v4l2_fh_init(struct v4l2_fh *fh, struct video_device *vdev); /** * v4l2_fh_add - Add the fh to the list of file handles on a video_device. * * @fh: pointer to &struct v4l2_fh * * .. note:: * The @fh file handle must be initialised first. */ void v4l2_fh_add(struct v4l2_fh *fh); /** * v4l2_fh_open - Ancillary routine that can be used as the open\(\) op * of v4l2_file_operations. * * @filp: pointer to struct file * * It allocates a v4l2_fh and inits and adds it to the &struct video_device * associated with the file pointer. */ int v4l2_fh_open(struct file *filp); /** * v4l2_fh_del - Remove file handle from the list of file handles. * * @fh: pointer to &struct v4l2_fh * * On error filp->private_data will be %NULL, otherwise it will point to * the &struct v4l2_fh. * * .. note:: * Must be called in v4l2_file_operations->release\(\) handler if the driver * uses &struct v4l2_fh. */ void v4l2_fh_del(struct v4l2_fh *fh); /** * v4l2_fh_exit - Release resources related to a file handle. * * @fh: pointer to &struct v4l2_fh * * Parts of the V4L2 framework using the v4l2_fh must release their * resources here, too. * * .. note:: * Must be called in v4l2_file_operations->release\(\) handler if the * driver uses &struct v4l2_fh. */ void v4l2_fh_exit(struct v4l2_fh *fh); /** * v4l2_fh_release - Ancillary routine that can be used as the release\(\) op * of v4l2_file_operations. * * @filp: pointer to struct file * * It deletes and exits the v4l2_fh associated with the file pointer and * frees it. It will do nothing if filp->private_data (the pointer to the * v4l2_fh struct) is %NULL. * * This function always returns 0. */ int v4l2_fh_release(struct file *filp); /** * v4l2_fh_is_singular - Returns 1 if this filehandle is the only filehandle * opened for the associated video_device. * * @fh: pointer to &struct v4l2_fh * * If @fh is NULL, then it returns 0. */ int v4l2_fh_is_singular(struct v4l2_fh *fh); /** * v4l2_fh_is_singular_file - Returns 1 if this filehandle is the only * filehandle opened for the associated video_device. * * @filp: pointer to struct file * * This is a helper function variant of v4l2_fh_is_singular() with uses * struct file as argument. * * If filp->private_data is %NULL, then it will return 0. */ static inline int v4l2_fh_is_singular_file(struct file *filp) { return v4l2_fh_is_singular(filp->private_data); } #endif /* V4L2_EVENT_H */ r> committerThomas Gleixner <tglx@linutronix.de>2017-01-31 21:47:58 +0100 commit0becc0ae5b42828785b589f686725ff5bc3b9b25 (patch) treebe6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101 /drivers/usb/misc/ehset.c parent24c2503255d35c269b67162c397a1a1c1e02f6ce (diff)
x86/mce: Make timer handling more robust
Erik reported that on a preproduction hardware a CMCI storm triggers the BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is started by the CMCI logic before the MCE CPU hotplug callback starts the timer with add_timer_on(). So the timer is already queued which triggers the BUG. Using add_timer_on() is pretty pointless in this code because the timer is strictlty per CPU, initialized as pinned and all operations which arm the timer happen on the CPU to which the timer belongs. Simplify the whole machinery by using mod_timer() instead of add_timer_on() which avoids the problem because mod_timer() can handle already queued timers. Use __start_timer() everywhere so the earliest armed expiry time is preserved. Reported-by: Erik Veijola <erik.veijola@intel.com> Tested-by: Borislav Petkov <bp@alien8.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Borislav Petkov <bp@alien8.de> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'drivers/usb/misc/ehset.c')