Drivers will need to save/restore the appropriate cgroup data for the process submitting a driver request. Add an interface for drivers to determine the cgroup for the userspace process submitting a driver request.
Cc: Tejun Heo <[email protected]> Cc: [email protected] Signed-off-by: Matt Roper <[email protected]> --- include/linux/cgroup.h | 6 ++++++ kernel/cgroup/cgroup_driver.c | 24 ++++++++++++++++++++++++ 2 files changed, 30 insertions(+) diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h index 0ba1374122c7..05ebfb97bcde 100644 --- a/include/linux/cgroup.h +++ b/include/linux/cgroup.h @@ -842,6 +842,7 @@ void cgroup_driver_release(struct cgroup_driver *drv); struct cgroup_driver_data * cgroup_driver_get_data(struct cgroup_driver *drv, struct cgroup *cgrp, bool *is_new); +struct cgroup *cgroup_for_driver_process(struct pid *pid); #else /* !CONFIG_CGROUP_DRIVER */ @@ -857,6 +858,11 @@ cgroup_driver_get_data(struct cgroup_driver *drv, { return ERR_PTR(-EINVAL); } +static inline struct cgroup * +cgroup_for_driver_process(struct pid *pid) +{ + return NULL; +} #endif /* !CONFIG_CGROUP_DRIVER */ diff --git a/kernel/cgroup/cgroup_driver.c b/kernel/cgroup/cgroup_driver.c index 0d893395dc7b..4f870cbb9212 100644 --- a/kernel/cgroup/cgroup_driver.c +++ b/kernel/cgroup/cgroup_driver.c @@ -128,3 +128,27 @@ cgroup_driver_get_data(struct cgroup_driver *drv, return data; } EXPORT_SYMBOL(cgroup_driver_get_data); + +/** + * cgroup_for_driver_process - return the cgroup for a process + * @pid: process to lookup cgroup for + * + * Returns the cgroup from the v2 hierarchy that a process belongs to. + * This function is intended to be called from drivers and will obtain + * the necessary cgroup locks. + * + * RETURNS: + * Process' cgroup in the default (v2) hierarchy + */ +struct cgroup * +cgroup_for_driver_process(struct pid *pid) +{ + struct task_struct *task = pid_task(pid, PIDTYPE_PID); + + mutex_lock(&cgroup_mutex); + spin_lock_irq(&css_set_lock); + task_cgroup_from_root(task, &cgrp_dfl_root); + spin_unlock_irq(&css_set_lock); + mutex_unlock(&cgroup_mutex); +} +EXPORT_SYMBOL(cgroup_for_driver_process); -- 2.14.3 _______________________________________________ Intel-gfx mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/intel-gfx
