Commit-ID: d6aaba615a482ce7d3ec218cf7b8d02d0d5753b8 Gitweb: http://git.kernel.org/tip/d6aaba615a482ce7d3ec218cf7b8d02d0d5753b8 Author: Vikas Shivappa <[email protected]> AuthorDate: Tue, 25 Jul 2017 14:14:34 -0700 Committer: Thomas Gleixner <[email protected]> CommitDate: Tue, 1 Aug 2017 22:41:24 +0200
x86/intel_rdt/cqm: Add tasks file support The root directory, ctrl_mon and monitor groups are populated with a read/write file named "tasks". When read, it shows all the task IDs assigned to the resource group. Tasks can be added to groups by writing the PID to the file. A task can be present in one "ctrl_mon" group "and" one "monitor" group. IOW a PID_x can be seen in a ctrl_mon group and a monitor group at the same time. When a task is added to a ctrl_mon group, it is automatically removed from the previous ctrl_mon group where it belonged. Similarly if a task is moved to a monitor group it is removed from the previous monitor group . Also since the monitor groups can only have subset of tasks of parent ctrl_mon group, a task can be moved to a monitor group only if its already present in the parent ctrl_mon group. Task membership is indicated by a new field in the task_struct "u32 rmid" which holds the RMID for the task. RMID=0 is reserved for the default root group where the tasks belong to at mount. [tony: zero the rmid if rdtgroup was deleted when task was being moved] Signed-off-by: Tony Luck <[email protected]> Signed-off-by: Vikas Shivappa <[email protected]> Signed-off-by: Thomas Gleixner <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Cc: [email protected] Link: http://lkml.kernel.org/r/1501017287-28083-16-git-send-email-vikas.shiva...@linux.intel.com --- arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 19 +++++++++++++++++-- include/linux/sched.h | 1 + 2 files changed, 18 insertions(+), 2 deletions(-) diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c index 8404054..aedad1d 100644 --- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c +++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c @@ -314,6 +314,7 @@ static void move_myself(struct callback_head *head) if (atomic_dec_and_test(&rdtgrp->waitcount) && (rdtgrp->flags & RDT_DELETED)) { current->closid = 0; + current->rmid = 0; kfree(rdtgrp); } @@ -352,7 +353,20 @@ static int __rdtgroup_move_task(struct task_struct *tsk, atomic_dec(&rdtgrp->waitcount); kfree(callback); } else { - tsk->closid = rdtgrp->closid; + /* + * For ctrl_mon groups move both closid and rmid. + * For monitor groups, can move the tasks only from + * their parent CTRL group. + */ + if (rdtgrp->type == RDTCTRL_GROUP) { + tsk->closid = rdtgrp->closid; + tsk->rmid = rdtgrp->mon.rmid; + } else if (rdtgrp->type == RDTMON_GROUP) { + if (rdtgrp->mon.parent->closid == tsk->closid) + tsk->rmid = rdtgrp->mon.rmid; + else + ret = -EINVAL; + } } return ret; } @@ -432,7 +446,8 @@ static void show_rdt_tasks(struct rdtgroup *r, struct seq_file *s) rcu_read_lock(); for_each_process_thread(p, t) { - if (t->closid == r->closid) + if ((r->type == RDTCTRL_GROUP && t->closid == r->closid) || + (r->type == RDTMON_GROUP && t->rmid == r->mon.rmid)) seq_printf(s, "%d\n", t->pid); } rcu_read_unlock(); diff --git a/include/linux/sched.h b/include/linux/sched.h index 8839fd0..067a41a 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -900,6 +900,7 @@ struct task_struct { #endif #ifdef CONFIG_INTEL_RDT u32 closid; + u32 rmid; #endif #ifdef CONFIG_FUTEX struct robust_list_head __user *robust_list;
