[mirror_ubuntu-bionic-kernel.git] / arch / x86 / kernel / cpu / intel_rdt_ctrlmondata.c

/*
 * Resource Director Technology(RDT)
 * - Cache Allocation code.
 *
 * Copyright (C) 2016 Intel Corporation
 *
 * Authors:
 *    Fenghua Yu <fenghua.yu@intel.com>
 *    Tony Luck <tony.luck@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms and conditions of the GNU General Public License,
 * version 2, as published by the Free Software Foundation.
 *
 * This program is distributed in the hope 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.
 *
 * More information about RDT be found in the Intel (R) x86 Architecture
 * Software Developer Manual June 2016, volume 3, section 17.17.
 */

#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt

#include <linux/kernfs.h>
#include <linux/seq_file.h>
#include <linux/slab.h>
#include "intel_rdt.h"

/*
 * Check whether MBA bandwidth percentage value is correct. The value is
 * checked against the minimum and max bandwidth values specified by the
 * hardware. The allocated bandwidth percentage is rounded to the next
 * control step available on the hardware.
 */
static bool bw_validate(char *buf, unsigned long *data, struct rdt_resource *r)
{
	unsigned long bw;
	int ret;

	/*
	 * Only linear delay values is supported for current Intel SKUs.
	 */
	if (!r->membw.delay_linear) {
		rdt_last_cmd_puts("No support for non-linear MB domains\n");
		return false;
	}

	ret = kstrtoul(buf, 10, &bw);
	if (ret) {
		rdt_last_cmd_printf("Non-decimal digit in MB value %s\n", buf);
		return false;
	}

	if (bw < r->membw.min_bw || bw > r->default_ctrl) {
		rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
				    r->membw.min_bw, r->default_ctrl);
		return false;
	}

	*data = roundup(bw, (unsigned long)r->membw.bw_gran);
	return true;
}

int parse_bw(char *buf, struct rdt_resource *r, struct rdt_domain *d)
{
	unsigned long data;

	if (d->have_new_ctrl) {
		rdt_last_cmd_printf("duplicate domain %d\n", d->id);
		return -EINVAL;
	}

	if (!bw_validate(buf, &data, r))
		return -EINVAL;
	d->new_ctrl = data;
	d->have_new_ctrl = true;

	return 0;
}

/*
 * Check whether a cache bit mask is valid. The SDM says:
 *	Please note that all (and only) contiguous '1' combinations
 *	are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.).
 * Additionally Haswell requires at least two bits set.
 */
static bool cbm_validate(char *buf, unsigned long *data, struct rdt_resource *r)
{
	unsigned long first_bit, zero_bit, val;
	unsigned int cbm_len = r->cache.cbm_len;
	int ret;

	ret = kstrtoul(buf, 16, &val);
	if (ret) {
		rdt_last_cmd_printf("non-hex character in mask %s\n", buf);
		return false;
	}

	if (val == 0 || val > r->default_ctrl) {
		rdt_last_cmd_puts("mask out of range\n");
		return false;
	}

	first_bit = find_first_bit(&val, cbm_len);
	zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);

	if (find_next_bit(&val, cbm_len, zero_bit) < cbm_len) {
		rdt_last_cmd_printf("mask %lx has non-consecutive 1-bits\n", val);
		return false;
	}

	if ((zero_bit - first_bit) < r->cache.min_cbm_bits) {
		rdt_last_cmd_printf("Need at least %d bits in mask\n",
				    r->cache.min_cbm_bits);
		return false;
	}

	*data = val;
	return true;
}

/*
 * Read one cache bit mask (hex). Check that it is valid for the current
 * resource type.
 */
int parse_cbm(char *buf, struct rdt_resource *r, struct rdt_domain *d)
{
	unsigned long data;

	if (d->have_new_ctrl) {
		rdt_last_cmd_printf("duplicate domain %d\n", d->id);
		return -EINVAL;
	}

	if(!cbm_validate(buf, &data, r))
		return -EINVAL;
	d->new_ctrl = data;
	d->have_new_ctrl = true;

	return 0;
}

/*
 * For each domain in this resource we expect to find a series of:
 *	id=mask
 * separated by ";". The "id" is in decimal, and must match one of
 * the "id"s for this resource.
 */
static int parse_line(char *line, struct rdt_resource *r)
{
	char *dom = NULL, *id;
	struct rdt_domain *d;
	unsigned long dom_id;

next:
	if (!line || line[0] == '\0')
		return 0;
	dom = strsep(&line, ";");
	id = strsep(&dom, "=");
	if (!dom || kstrtoul(id, 10, &dom_id)) {
		rdt_last_cmd_puts("Missing '=' or non-numeric domain\n");
		return -EINVAL;
	}
	dom = strim(dom);
	list_for_each_entry(d, &r->domains, list) {
		if (d->id == dom_id) {
			if (r->parse_ctrlval(dom, r, d))
				return -EINVAL;
			goto next;
		}
	}
	return -EINVAL;
}

static int update_domains(struct rdt_resource *r, int closid)
{
	struct msr_param msr_param;
	cpumask_var_t cpu_mask;
	struct rdt_domain *d;
	int cpu;

	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
		return -ENOMEM;

	msr_param.low = closid;
	msr_param.high = msr_param.low + 1;
	msr_param.res = r;

	list_for_each_entry(d, &r->domains, list) {
		if (d->have_new_ctrl && d->new_ctrl != d->ctrl_val[closid]) {
			cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
			d->ctrl_val[closid] = d->new_ctrl;
		}
	}
	if (cpumask_empty(cpu_mask))
		goto done;
	cpu = get_cpu();
	/* Update CBM on this cpu if it's in cpu_mask. */
	if (cpumask_test_cpu(cpu, cpu_mask))
		rdt_ctrl_update(&msr_param);
	/* Update CBM on other cpus. */
	smp_call_function_many(cpu_mask, rdt_ctrl_update, &msr_param, 1);
	put_cpu();

done:
	free_cpumask_var(cpu_mask);

	return 0;
}

static int rdtgroup_parse_resource(char *resname, char *tok, int closid)
{
	struct rdt_resource *r;

	for_each_alloc_enabled_rdt_resource(r) {
		if (!strcmp(resname, r->name) && closid < r->num_closid)
			return parse_line(tok, r);
	}
	rdt_last_cmd_printf("unknown/unsupported resource name '%s'\n", resname);
	return -EINVAL;
}

ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
				char *buf, size_t nbytes, loff_t off)
{
	struct rdtgroup *rdtgrp;
	struct rdt_domain *dom;
	struct rdt_resource *r;
	char *tok, *resname;
	int closid, ret = 0;

	/* Valid input requires a trailing newline */
	if (nbytes == 0 || buf[nbytes - 1] != '\n')
		return -EINVAL;
	buf[nbytes - 1] = '\0';

	rdtgrp = rdtgroup_kn_lock_live(of->kn);
	if (!rdtgrp) {
		rdtgroup_kn_unlock(of->kn);
		return -ENOENT;
	}
	rdt_last_cmd_clear();

	closid = rdtgrp->closid;

	for_each_alloc_enabled_rdt_resource(r) {
		list_for_each_entry(dom, &r->domains, list)
			dom->have_new_ctrl = false;
	}

	while ((tok = strsep(&buf, "\n")) != NULL) {
		resname = strim(strsep(&tok, ":"));
		if (!tok) {
			rdt_last_cmd_puts("Missing ':'\n");
			ret = -EINVAL;
			goto out;
		}
		if (tok[0] == '\0') {
			rdt_last_cmd_printf("Missing '%s' value\n", resname);
			ret = -EINVAL;
			goto out;
		}
		ret = rdtgroup_parse_resource(resname, tok, closid);
		if (ret)
			goto out;
	}

	for_each_alloc_enabled_rdt_resource(r) {
		ret = update_domains(r, closid);
		if (ret)
			goto out;
	}

out:
	rdtgroup_kn_unlock(of->kn);
	return ret ?: nbytes;
}

static void show_doms(struct seq_file *s, struct rdt_resource *r, int closid)
{
	struct rdt_domain *dom;
	bool sep = false;

	seq_printf(s, "%*s:", max_name_width, r->name);
	list_for_each_entry(dom, &r->domains, list) {
		if (sep)
			seq_puts(s, ";");
		seq_printf(s, r->format_str, dom->id, max_data_width,
			   dom->ctrl_val[closid]);
		sep = true;
	}
	seq_puts(s, "\n");
}

int rdtgroup_schemata_show(struct kernfs_open_file *of,
			   struct seq_file *s, void *v)
{
	struct rdtgroup *rdtgrp;
	struct rdt_resource *r;
	int ret = 0;
	u32 closid;

	rdtgrp = rdtgroup_kn_lock_live(of->kn);
	if (rdtgrp) {
		closid = rdtgrp->closid;
		for_each_alloc_enabled_rdt_resource(r) {
			if (closid < r->num_closid)
				show_doms(s, r, closid);
		}
	} else {
		ret = -ENOENT;
	}
	rdtgroup_kn_unlock(of->kn);
	return ret;
}

void mon_event_read(struct rmid_read *rr, struct rdt_domain *d,
		    struct rdtgroup *rdtgrp, int evtid, int first)
{
	/*
	 * setup the parameters to send to the IPI to read the data.
	 */
	rr->rgrp = rdtgrp;
	rr->evtid = evtid;
	rr->d = d;
	rr->val = 0;
	rr->first = first;

	smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
}

int rdtgroup_mondata_show(struct seq_file *m, void *arg)
{
	struct kernfs_open_file *of = m->private;
	u32 resid, evtid, domid;
	struct rdtgroup *rdtgrp;
	struct rdt_resource *r;
	union mon_data_bits md;
	struct rdt_domain *d;
	struct rmid_read rr;
	int ret = 0;

	rdtgrp = rdtgroup_kn_lock_live(of->kn);

	md.priv = of->kn->priv;
	resid = md.u.rid;
	domid = md.u.domid;
	evtid = md.u.evtid;

	r = &rdt_resources_all[resid];
	d = rdt_find_domain(r, domid, NULL);
	if (!d) {
		ret = -ENOENT;
		goto out;
	}

	mon_event_read(&rr, d, rdtgrp, evtid, false);

	if (rr.val & RMID_VAL_ERROR)
		seq_puts(m, "Error\n");
	else if (rr.val & RMID_VAL_UNAVAIL)
		seq_puts(m, "Unavailable\n");
	else
		seq_printf(m, "%llu\n", rr.val * r->mon_scale);

out:
	rdtgroup_kn_unlock(of->kn);
	return ret;
}
Commit	Line	Data
60ec2440 TL	1	/*
	2	* Resource Director Technology(RDT)
	3	* - Cache Allocation code.
	4	*
	5	* Copyright (C) 2016 Intel Corporation
	6	*
	7	* Authors:
	8	* Fenghua Yu <fenghua.yu@intel.com>
	9	* Tony Luck <tony.luck@intel.com>
	10	*
	11	* This program is free software; you can redistribute it and/or modify it
	12	* under the terms and conditions of the GNU General Public License,
	13	* version 2, as published by the Free Software Foundation.
	14	*
	15	* This program is distributed in the hope it will be useful, but WITHOUT
	16	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	17	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	18	* more details.
	19	*
	20	* More information about RDT be found in the Intel (R) x86 Architecture
	21	* Software Developer Manual June 2016, volume 3, section 17.17.
	22	*/
	23
	24	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
	25
	26	#include <linux/kernfs.h>
	27	#include <linux/seq_file.h>
	28	#include <linux/slab.h>
05830204	29	#include "intel_rdt.h"
60ec2440	30
64e8ed3d VS	31	/*
	32	* Check whether MBA bandwidth percentage value is correct. The value is
	33	* checked against the minimum and max bandwidth values specified by the
	34	* hardware. The allocated bandwidth percentage is rounded to the next
	35	* control step available on the hardware.
	36	*/
	37	static bool bw_validate(char buf, unsigned long data, struct rdt_resource *r)
	38	{
	39	unsigned long bw;
	40	int ret;
	41
	42	/*
	43	* Only linear delay values is supported for current Intel SKUs.
	44	*/
c377dcfb TL	45	if (!r->membw.delay_linear) {
c377dcfb TL	46	rdt_last_cmd_puts("No support for non-linear MB domains\n");
64e8ed3d	47	return false;
c377dcfb	48	}
64e8ed3d VS	49
64e8ed3d VS	50	ret = kstrtoul(buf, 10, &bw);
c377dcfb TL	51	if (ret) {
c377dcfb TL	52	rdt_last_cmd_printf("Non-decimal digit in MB value %s\n", buf);
64e8ed3d	53	return false;
c377dcfb	54	}
64e8ed3d	55
c377dcfb TL	56	if (bw < r->membw.min_bw \|\| bw > r->default_ctrl) {
	57	rdt_last_cmd_printf("MB value %ld out of range [%d,%d]\n", bw,
	58	r->membw.min_bw, r->default_ctrl);
64e8ed3d	59	return false;
c377dcfb	60	}
64e8ed3d VS	61
	62	*data = roundup(bw, (unsigned long)r->membw.bw_gran);
	63	return true;
	64	}
	65
	66	int parse_bw(char buf, struct rdt_resource r, struct rdt_domain *d)
	67	{
	68	unsigned long data;
	69
c377dcfb TL	70	if (d->have_new_ctrl) {
c377dcfb TL	71	rdt_last_cmd_printf("duplicate domain %d\n", d->id);
64e8ed3d	72	return -EINVAL;
c377dcfb	73	}
64e8ed3d VS	74
	75	if (!bw_validate(buf, &data, r))
	76	return -EINVAL;
	77	d->new_ctrl = data;
	78	d->have_new_ctrl = true;
	79
	80	return 0;
	81	}
	82
60ec2440 TL	83	/*
	84	* Check whether a cache bit mask is valid. The SDM says:
	85	* Please note that all (and only) contiguous '1' combinations
	86	* are allowed (e.g. FFFFH, 0FF0H, 003CH, etc.).
	87	* Additionally Haswell requires at least two bits set.
	88	*/
c6ea67de	89	static bool cbm_validate(char buf, unsigned long data, struct rdt_resource *r)
60ec2440	90	{
c6ea67de	91	unsigned long first_bit, zero_bit, val;
d3e11b4d	92	unsigned int cbm_len = r->cache.cbm_len;
c6ea67de VS	93	int ret;
	94
	95	ret = kstrtoul(buf, 16, &val);
c377dcfb TL	96	if (ret) {
c377dcfb TL	97	rdt_last_cmd_printf("non-hex character in mask %s\n", buf);
c6ea67de	98	return false;
c377dcfb	99	}
60ec2440	100
c377dcfb TL	101	if (val == 0 \|\| val > r->default_ctrl) {
c377dcfb TL	102	rdt_last_cmd_puts("mask out of range\n");
60ec2440	103	return false;
c377dcfb	104	}
60ec2440	105
c6ea67de VS	106	first_bit = find_first_bit(&val, cbm_len);
c6ea67de VS	107	zero_bit = find_next_zero_bit(&val, cbm_len, first_bit);
60ec2440	108
c377dcfb TL	109	if (find_next_bit(&val, cbm_len, zero_bit) < cbm_len) {
c377dcfb TL	110	rdt_last_cmd_printf("mask %lx has non-consecutive 1-bits\n", val);
60ec2440	111	return false;
c377dcfb	112	}
60ec2440	113
c377dcfb TL	114	if ((zero_bit - first_bit) < r->cache.min_cbm_bits) {
	115	rdt_last_cmd_printf("Need at least %d bits in mask\n",
	116	r->cache.min_cbm_bits);
60ec2440	117	return false;
c377dcfb	118	}
c6ea67de VS	119
c6ea67de VS	120	*data = val;
60ec2440 TL	121	return true;
	122	}
	123
	124	/*
	125	* Read one cache bit mask (hex). Check that it is valid for the current
	126	* resource type.
	127	*/
c6ea67de	128	int parse_cbm(char buf, struct rdt_resource r, struct rdt_domain *d)
60ec2440 TL	129	{
60ec2440 TL	130	unsigned long data;
60ec2440	131
c377dcfb TL	132	if (d->have_new_ctrl) {
c377dcfb TL	133	rdt_last_cmd_printf("duplicate domain %d\n", d->id);
c4026b7b	134	return -EINVAL;
c377dcfb	135	}
c4026b7b	136
c6ea67de	137	if(!cbm_validate(buf, &data, r))
60ec2440	138	return -EINVAL;
2545e9f5 VS	139	d->new_ctrl = data;
2545e9f5 VS	140	d->have_new_ctrl = true;
60ec2440 TL	141
	142	return 0;
	143	}
	144
	145	/*
	146	* For each domain in this resource we expect to find a series of:
	147	* id=mask
c4026b7b TL	148	* separated by ";". The "id" is in decimal, and must match one of
c4026b7b TL	149	* the "id"s for this resource.
60ec2440 TL	150	*/
	151	static int parse_line(char line, struct rdt_resource r)
	152	{
	153	char dom = NULL, id;
	154	struct rdt_domain *d;
	155	unsigned long dom_id;
	156
c4026b7b TL	157	next:
	158	if (!line \|\| line[0] == '\0')
	159	return 0;
	160	dom = strsep(&line, ";");
	161	id = strsep(&dom, "=");
c377dcfb TL	162	if (!dom \|\| kstrtoul(id, 10, &dom_id)) {
c377dcfb TL	163	rdt_last_cmd_puts("Missing '=' or non-numeric domain\n");
c4026b7b	164	return -EINVAL;
c377dcfb	165	}
634b0e04	166	dom = strim(dom);
60ec2440	167	list_for_each_entry(d, &r->domains, list) {
c4026b7b	168	if (d->id == dom_id) {
c6ea67de	169	if (r->parse_ctrlval(dom, r, d))
c4026b7b TL	170	return -EINVAL;
	171	goto next;
	172	}
60ec2440	173	}
c4026b7b	174	return -EINVAL;
60ec2440 TL	175	}
	176
	177	static int update_domains(struct rdt_resource *r, int closid)
	178	{
	179	struct msr_param msr_param;
	180	cpumask_var_t cpu_mask;
	181	struct rdt_domain *d;
c4026b7b	182	int cpu;
60ec2440 TL	183
	184	if (!zalloc_cpumask_var(&cpu_mask, GFP_KERNEL))
	185	return -ENOMEM;
	186
	187	msr_param.low = closid;
	188	msr_param.high = msr_param.low + 1;
	189	msr_param.res = r;
	190
	191	list_for_each_entry(d, &r->domains, list) {
2545e9f5	192	if (d->have_new_ctrl && d->new_ctrl != d->ctrl_val[closid]) {
c4026b7b	193	cpumask_set_cpu(cpumask_any(&d->cpu_mask), cpu_mask);
2545e9f5	194	d->ctrl_val[closid] = d->new_ctrl;
c4026b7b	195	}
60ec2440	196	}
c4026b7b TL	197	if (cpumask_empty(cpu_mask))
c4026b7b TL	198	goto done;
60ec2440 TL	199	cpu = get_cpu();
	200	/* Update CBM on this cpu if it's in cpu_mask. */
	201	if (cpumask_test_cpu(cpu, cpu_mask))
2545e9f5	202	rdt_ctrl_update(&msr_param);
60ec2440	203	/* Update CBM on other cpus. */
2545e9f5	204	smp_call_function_many(cpu_mask, rdt_ctrl_update, &msr_param, 1);
60ec2440 TL	205	put_cpu();
60ec2440 TL	206
c4026b7b	207	done:
60ec2440 TL	208	free_cpumask_var(cpu_mask);
	209
	210	return 0;
	211	}
	212
4797b7df VS	213	static int rdtgroup_parse_resource(char resname, char tok, int closid)
	214	{
	215	struct rdt_resource *r;
	216
1b5c0b75	217	for_each_alloc_enabled_rdt_resource(r) {
4797b7df VS	218	if (!strcmp(resname, r->name) && closid < r->num_closid)
	219	return parse_line(tok, r);
	220	}
c377dcfb	221	rdt_last_cmd_printf("unknown/unsupported resource name '%s'\n", resname);
4797b7df VS	222	return -EINVAL;
	223	}
	224
60ec2440 TL	225	ssize_t rdtgroup_schemata_write(struct kernfs_open_file *of,
	226	char *buf, size_t nbytes, loff_t off)
	227	{
	228	struct rdtgroup *rdtgrp;
c4026b7b	229	struct rdt_domain *dom;
60ec2440 TL	230	struct rdt_resource *r;
	231	char tok, resname;
	232	int closid, ret = 0;
60ec2440 TL	233
60ec2440 TL	234	/* Valid input requires a trailing newline */
29e74f35	235	if (nbytes == 0 \|\| buf[nbytes - 1] != '\n')
60ec2440 TL	236	return -EINVAL;
	237	buf[nbytes - 1] = '\0';
	238
	239	rdtgrp = rdtgroup_kn_lock_live(of->kn);
	240	if (!rdtgrp) {
	241	rdtgroup_kn_unlock(of->kn);
	242	return -ENOENT;
	243	}
c377dcfb	244	rdt_last_cmd_clear();
60ec2440 TL	245
	246	closid = rdtgrp->closid;
	247
1b5c0b75	248	for_each_alloc_enabled_rdt_resource(r) {
c4026b7b	249	list_for_each_entry(dom, &r->domains, list)
2545e9f5	250	dom->have_new_ctrl = false;
4797b7df	251	}
60ec2440 TL	252
60ec2440 TL	253	while ((tok = strsep(&buf, "\n")) != NULL) {
634b0e04	254	resname = strim(strsep(&tok, ":"));
60ec2440	255	if (!tok) {
c377dcfb	256	rdt_last_cmd_puts("Missing ':'\n");
60ec2440 TL	257	ret = -EINVAL;
	258	goto out;
	259	}
2244645a XS	260	if (tok[0] == '\0') {
	261	rdt_last_cmd_printf("Missing '%s' value\n", resname);
	262	ret = -EINVAL;
	263	goto out;
	264	}
4797b7df VS	265	ret = rdtgroup_parse_resource(resname, tok, closid);
4797b7df VS	266	if (ret)
60ec2440	267	goto out;
60ec2440 TL	268	}
60ec2440 TL	269
1b5c0b75	270	for_each_alloc_enabled_rdt_resource(r) {
60ec2440 TL	271	ret = update_domains(r, closid);
	272	if (ret)
	273	goto out;
	274	}
	275
	276	out:
	277	rdtgroup_kn_unlock(of->kn);
60ec2440 TL	278	return ret ?: nbytes;
	279	}
	280
	281	static void show_doms(struct seq_file s, struct rdt_resource r, int closid)
	282	{
	283	struct rdt_domain *dom;
	284	bool sep = false;
	285
de016df8	286	seq_printf(s, "%*s:", max_name_width, r->name);
60ec2440 TL	287	list_for_each_entry(dom, &r->domains, list) {
	288	if (sep)
	289	seq_puts(s, ";");
c6ea67de	290	seq_printf(s, r->format_str, dom->id, max_data_width,
2545e9f5	291	dom->ctrl_val[closid]);
60ec2440 TL	292	sep = true;
	293	}
	294	seq_puts(s, "\n");
	295	}
	296
	297	int rdtgroup_schemata_show(struct kernfs_open_file *of,
	298	struct seq_file s, void v)
	299	{
	300	struct rdtgroup *rdtgrp;
	301	struct rdt_resource *r;
d89b7379 VS	302	int ret = 0;
d89b7379 VS	303	u32 closid;
60ec2440 TL	304
	305	rdtgrp = rdtgroup_kn_lock_live(of->kn);
	306	if (rdtgrp) {
	307	closid = rdtgrp->closid;
1b5c0b75	308	for_each_alloc_enabled_rdt_resource(r) {
60ec2440 TL	309	if (closid < r->num_closid)
	310	show_doms(s, r, closid);
	311	}
	312	} else {
	313	ret = -ENOENT;
	314	}
	315	rdtgroup_kn_unlock(of->kn);
	316	return ret;
	317	}
d89b7379 VS	318
d89b7379 VS	319	void mon_event_read(struct rmid_read rr, struct rdt_domain d,
a4de1dfd	320	struct rdtgroup *rdtgrp, int evtid, int first)
d89b7379 VS	321	{
	322	/*
	323	* setup the parameters to send to the IPI to read the data.
	324	*/
	325	rr->rgrp = rdtgrp;
	326	rr->evtid = evtid;
9f52425b	327	rr->d = d;
d89b7379	328	rr->val = 0;
a4de1dfd	329	rr->first = first;
d89b7379 VS	330
	331	smp_call_function_any(&d->cpu_mask, mon_event_count, rr, 1);
	332	}
	333
	334	int rdtgroup_mondata_show(struct seq_file m, void arg)
	335	{
	336	struct kernfs_open_file *of = m->private;
	337	u32 resid, evtid, domid;
	338	struct rdtgroup *rdtgrp;
	339	struct rdt_resource *r;
	340	union mon_data_bits md;
	341	struct rdt_domain *d;
	342	struct rmid_read rr;
	343	int ret = 0;
	344
	345	rdtgrp = rdtgroup_kn_lock_live(of->kn);
	346
	347	md.priv = of->kn->priv;
	348	resid = md.u.rid;
	349	domid = md.u.domid;
	350	evtid = md.u.evtid;
	351
	352	r = &rdt_resources_all[resid];
	353	d = rdt_find_domain(r, domid, NULL);
	354	if (!d) {
	355	ret = -ENOENT;
	356	goto out;
	357	}
	358
a4de1dfd	359	mon_event_read(&rr, d, rdtgrp, evtid, false);
d89b7379 VS	360
	361	if (rr.val & RMID_VAL_ERROR)
	362	seq_puts(m, "Error\n");
	363	else if (rr.val & RMID_VAL_UNAVAIL)
	364	seq_puts(m, "Unavailable\n");
	365	else
	366	seq_printf(m, "%llu\n", rr.val * r->mon_scale);
	367
	368	out:
	369	rdtgroup_kn_unlock(of->kn);
	370	return ret;
	371	}