Commit 4244057c authored by Linus Torvalds's avatar Linus Torvalds
Browse files

Merge branch 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 

Pull x86 resource control updates from Ingo Molnar:
 "The main change in this tree is the extension of the resctrl procfs
  ABI with a new file that helps tooling to navigate from tasks back to
  resctrl groups: /proc/{pid}/cpu_resctrl_groups.

  Also fix static key usage for certain feature combinations and
  simplify the task exit resctrl case"

* 'x86-cache-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/resctrl: Add task resctrl information display
  x86/resctrl: Check monitoring static key in the MBM overflow handler
  x86/resctrl: Do not reconfigure exiting tasks
parents 6b90e71a e79f15a4

arch/x86/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -457,6 +457,7 @@ config X86_CPU_RESCTRL 
	bool "x86 CPU resource control support"

	depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)

	select KERNFS

	select PROC_CPU_RESCTRL		if PROC_FS

	help

	  Enable x86 CPU resource control support.

arch/x86/kernel/cpu/resctrl/internal.h

+1 −0
Original line number Diff line number Diff line
@@ -57,6 +57,7 @@ static inline struct rdt_fs_context *rdt_fc2context(struct fs_context *fc) 
}



DECLARE_STATIC_KEY_FALSE(rdt_enable_key);

DECLARE_STATIC_KEY_FALSE(rdt_mon_enable_key);



/**

 * struct mon_evt - Entry in the event list of a resource

arch/x86/kernel/cpu/resctrl/monitor.c

+2 −2
Original line number Diff line number Diff line
@@ -514,7 +514,7 @@ void mbm_handle_overflow(struct work_struct *work) 


	mutex_lock(&rdtgroup_mutex);



	if (!static_branch_likely(&rdt_enable_key))

	if (!static_branch_likely(&rdt_mon_enable_key))

		goto out_unlock;



	d = get_domain_from_cpu(cpu, &rdt_resources_all[RDT_RESOURCE_L3]);
@@ -543,7 +543,7 @@ void mbm_setup_overflow_handler(struct rdt_domain *dom, unsigned long delay_ms) 
	unsigned long delay = msecs_to_jiffies(delay_ms);

	int cpu;



	if (!static_branch_likely(&rdt_enable_key))

	if (!static_branch_likely(&rdt_mon_enable_key))

		return;

	cpu = cpumask_any(&dom->cpu_mask);

	dom->mbm_work_cpu = cpu;

arch/x86/kernel/cpu/resctrl/rdtgroup.c

+90 −0
Original line number Diff line number Diff line
@@ -532,11 +532,15 @@ static void move_myself(struct callback_head *head) 
		kfree(rdtgrp);

	}



	if (unlikely(current->flags & PF_EXITING))

		goto out;



	preempt_disable();

	/* update PQR_ASSOC MSR to make resource group go into effect */

	resctrl_sched_in();

	preempt_enable();



out:

	kfree(callback);

}
@@ -725,6 +729,92 @@ static int rdtgroup_tasks_show(struct kernfs_open_file *of, 
	return ret;

}



#ifdef CONFIG_PROC_CPU_RESCTRL



/*

 * A task can only be part of one resctrl control group and of one monitor

 * group which is associated to that control group.

 *

 * 1)   res:

 *      mon:

 *

 *    resctrl is not available.

 *

 * 2)   res:/

 *      mon:

 *

 *    Task is part of the root resctrl control group, and it is not associated

 *    to any monitor group.

 *

 * 3)  res:/

 *     mon:mon0

 *

 *    Task is part of the root resctrl control group and monitor group mon0.

 *

 * 4)  res:group0

 *     mon:

 *

 *    Task is part of resctrl control group group0, and it is not associated

 *    to any monitor group.

 *

 * 5) res:group0

 *    mon:mon1

 *

 *    Task is part of resctrl control group group0 and monitor group mon1.

 */

int proc_resctrl_show(struct seq_file *s, struct pid_namespace *ns,

		      struct pid *pid, struct task_struct *tsk)

{

	struct rdtgroup *rdtg;

	int ret = 0;



	mutex_lock(&rdtgroup_mutex);



	/* Return empty if resctrl has not been mounted. */

	if (!static_branch_unlikely(&rdt_enable_key)) {

		seq_puts(s, "res:\nmon:\n");

		goto unlock;

	}



	list_for_each_entry(rdtg, &rdt_all_groups, rdtgroup_list) {

		struct rdtgroup *crg;



		/*

		 * Task information is only relevant for shareable

		 * and exclusive groups.

		 */

		if (rdtg->mode != RDT_MODE_SHAREABLE &&

		    rdtg->mode != RDT_MODE_EXCLUSIVE)

			continue;



		if (rdtg->closid != tsk->closid)

			continue;



		seq_printf(s, "res:%s%s\n", (rdtg == &rdtgroup_default) ? "/" : "",

			   rdtg->kn->name);

		seq_puts(s, "mon:");

		list_for_each_entry(crg, &rdtg->mon.crdtgrp_list,

				    mon.crdtgrp_list) {

			if (tsk->rmid != crg->mon.rmid)

				continue;

			seq_printf(s, "%s", crg->kn->name);

			break;

		}

		seq_putc(s, '\n');

		goto unlock;

	}

	/*

	 * The above search should succeed. Otherwise return

	 * with an error.

	 */

	ret = -ENOENT;

unlock:

	mutex_unlock(&rdtgroup_mutex);



	return ret;

}

#endif



static int rdt_last_cmd_status_show(struct kernfs_open_file *of,

				    struct seq_file *seq, void *v)

{

fs/proc/Kconfig

+4 −0
Original line number Diff line number Diff line
@@ -103,3 +103,7 @@ config PROC_CHILDREN 
config PROC_PID_ARCH_STATUS

	def_bool n

	depends on PROC_FS



config PROC_CPU_RESCTRL

	def_bool n

	depends on PROC_FS

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