Merge tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Don't destroy user event fields when removal fails

   User event fields are destroyed before the event is removed from
   visibility. But that can fail leaving the still visible event with no
   fields. Move the destroying of the fields to after the event is
   successfully removed from visibility.

 - Initialize function graph state is fork before calling
   copy_exec_state()

   For non-CLONE_VM forks, copy_exec_state() allocates a new
   task_exec_state. If that allocation fails, ftrace_graph_exit_task()
   will free the tasks ret_stack pointer. Since that pointer is still
   using the parent's ret_stack, it mistakenly frees the parent's
   pointer too.

   Call ftrace_graph_init() on the task first which will NULL out the
   new tasks's ret_stack and if the copy fails, it will not free
   anything.

 - Remove FGRAPH_MAX_INDEX

   The macro FGRAPH_MAX_INDEX was added but never used. Remove it.

 - Save ent_size in function graph printing of nested functions

   The function graph tracer needs to look at the next event to see if
   the next event is the return of the current function entry. If it is,
   it prints a single line:

	ktime_get();

   Otherwise it prints it like a nested function:

	tick_nohz_irq_exit() {
	    ktime_get();
	    kcpustat_irq_exit();
	}

   In order to look at the next event, it must save the current event so
   that it has the information to print from it. It saves the event in
   the iterator descriptor called "ent". What it doesn't save is the
   ent_size of the event which is now used to know if the function graph
   arguments are to be printed. The peek doesn't save the size so the
   size used happens to be that of the size of the last event that was
   seen.

   Save the entry event size in the iterator descriptor so that the
   correct size is used.

 - Fix several errors with freeing data in the histogram code

   The histogram code had a lot of leaked or or incorrect accounting
   when failures happen. Correct them.

 - Fix histogram regression of .percent and .graph modifiers

   Up until 6.3 histogram values could have "percent" or "graph"
   modifiers that changed how they were printed. But a change that added
   restricting histograms values from being strings, stack traces and
   other modifiers inadvertently prevented them from using the percent
   and graph modifiers, which were legal use cases for values.

   Put back the percent and graph modifiers.

 - Fix various typos in the comments

 - Set the trace_clock before initializing a histogram with clock
   argument

   The histogram API allows the user to specific which trace clock to
   use via a "clock=" string. The histogram is set up first before the
   clock is checked. If the passed in clock is not valid, it exits
   without fully fixing up the histogram leaving it on the list and a
   use-after-free can trigger.

   Update the clock argument first and if it fails then exit gracefully
   before the histogram trigger is placed on any lists.

 - Restore :mod: trailer after parsing in ftrace_set_clr_event

   The function ftrace_set_clr_event() modifies the parse string and
   needs to put it back to what was passed in. It searches for ":mod:"
   via a strsep() but fails to put back the first ':' in the string.

   Add back the ':' in the passed in string.

 - Take trace_array reference when opening a tracer options file

   The options files are dynamically created and some tracers add their
   own options. When a tracer adds their own list of options, the
   trace_array holding them has an array to hold the list of options for
   each tracer. This array increases in size via a krealloc(), and the
   new entry gets a newly allocated array to hold the options of the new
   tracer being added.

   The element in each entry of the tracer's option array holds a
   pointer back to the trace_array, a pointer to the tracer it is
   associated to, a pointer to the flags of the option.

   The issue is that these arrays are freed when the trace_array is
   freed when its instance it represents is removed from the instances
   directory. There's a race that an open of one of these options files
   can happen when the instance is being removed.

   Add a new helper function to be called by the open function of the
   options file to iterate all existing trace_arrays under a lock and
   find the one that has the given option element in one of it's tracer
   arrays. If found, then update the associated trace_array's reference
   counter to keep it from being freed. If not found, have the open call
   return -ENODEV.

 - Disable interrupts when acquiring the lock in rb_wake_up_waiters()

   The function rb_wake_up_waiters() assumes it will be called in
   interrupt context and does not disable irqs when taking
   cpu_buffer->reader_lock, which can be called in hard interrupt
   context. The issue is in PREEMPT_RT, this function is called in
   thread context leaving this lock open to a deadlock.

   Take the lock with interrupts disabled.

 - Use rcu_assign_pointer() for tmp_ops filter hash

   The tmp_ops used in update_ftrace_direct_mod() assigns its
   filter_hash field directly, but that field is annotated as __rcu and
   sparse complains. Assign it with rcu_assign_pointer()

 - Fix use-after-free in enable_trigger_private_data_free()

   The trace_event_call is accessed through the event_trigger_data's
   trace_event_file pointer to put the trace_event_call on freeing. The
   issue is that the trace_event_file data may have been freed already
   causing a use-after-free. Add a field to the event_trigger_data that
   points directly to the trace_event_call so that it can decrement its
   reference directly without needing to go through the
   trace_event_file.

 - Fix accounting of buffer data remote headers

   trace_buffer_desc_size() and trace_remote_alloc_buffer() undercount
   the number of pages is needed for the asked for size as it doesn't
   take into account the meta data on each page. Add a helper function
   to do the calculation properly and use that in these functions.

 - Catch nr_page_va overflow in ring_buffer_desc sizing

   The number of pages per remote ring buffer is capped by
   ring_buffer_desc::nr_page_va (32 bits). A buffer_size large enough to
   overflow that field would silently allocate a descriptor smaller than
   what was asked for.

 - Do not resize the subbuf order if any per_cpu buffer is disabled

   The mmapping of ring buffers disables resizing the subbuffers, but it
   is done per-cpu whereas the subbuf size change is done for all the
   per_cpu buffers under the buffer->mutex. It could change the size of
   some while the mapping is happening on others. Have the resize of the
   subbuf order check all the per_cpu buffers under the lock to see if
   any of them is disabled before starting and causing an inconsistency
   between buffers that are being mapped.

* tag 'trace-v7.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (25 commits)
  ring-buffer: Check resize_disabled before publishing the new subbuf order
  tracing/remotes: Catch nr_page_va overflow in ring_buffer_desc sizing
  tracing/remotes: Account for ring buffer page header in size calculation
  tracing: Don't dereference trace_event_file in deferred trigger free
  ftrace: Use rcu_assign_pointer() for tmp_ops filter hash
  ring-buffer: Acquire the lock with irqsave in rb_wake_up_waiters()
  tracing: Take trace_array reference when opening a tracer options file
  tracing: Fix ring_buffer_read_page_size() kernel-doc
  tracing: Restore :mod: trailer after parsing in ftrace_set_clr_event()
  tracing: Fix memory corruption from a "STACKTRACE" histogram key
  tracing: Fix memory corruption from the histogram stacktrace modifier
  tracing: Undo the registration when enabling the histogram trigger fails
  tracing: Take the reference before publishing the named histogram trigger
  tracing: Set the trace clock before registering the histogram trigger
  tracing: Fix typo "preceeded" in comment
  tracing: Fix typo "availabe" in comment
  tracing: Let histogram values keep the percent and graph modifiers
  tracing: Keep the entry count when the histogram stats allocation fails
  tracing: Free histogram the field rejected for a bad modifier
  tracing: Free histogram the var ref when its initialization fails
  ...

1 files changed, 1075 insertions, 0 deletions

diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
new file mode 100644
index 000000000..18ec9f564
--- /dev/null
+++ b/fs/resctrl/ctrlmondata.c
@@ -0,0 +1,1075 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ *
+ * 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/cpu.h>
+#include <linux/kernfs.h>
+#include <linux/math.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <linux/tick.h>
+
+#include "internal.h"
+
+struct rdt_parse_data {
+	u32			closid;
+	enum rdtgrp_mode	mode;
+	char			*buf;
+};
+
+typedef int (ctrlval_parser_t)(struct rdt_parse_data *data,
+			       struct resctrl_schema *s,
+			       struct rdt_ctrl_domain *d);
+
+/*
+ * 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, u32 *data, struct rdt_resource *r)
+{
+	int ret;
+	u32 bw;
+
+	/*
+	 * Only linear delay values is supported for current Intel SKUs.
+	 */
+	if (!r->membw.delay_linear && r->membw.arch_needs_linear) {
+		rdt_last_cmd_puts("No support for non-linear MB domains\n");
+		return false;
+	}
+
+	ret = kstrtou32(buf, 10, &bw);
+	if (ret) {
+		rdt_last_cmd_printf("Invalid MB value %s\n", buf);
+		return false;
+	}
+
+	/* Nothing else to do if software controller is enabled. */
+	if (is_mba_sc(r)) {
+		*data = bw;
+		return true;
+	}
+
+	if (bw < r->membw.min_bw || bw > r->membw.max_bw) {
+		rdt_last_cmd_printf("MB value %u out of range [%d,%d]\n",
+				    bw, r->membw.min_bw, r->membw.max_bw);
+		return false;
+	}
+
+	*data = roundup(bw, (unsigned long)r->membw.bw_gran);
+	return true;
+}
+
+static int parse_bw(struct rdt_parse_data *data, struct resctrl_schema *s,
+		    struct rdt_ctrl_domain *d)
+{
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	u32 closid = data->closid;
+	u32 bw_val;
+
+	cfg = &d->staged_config[s->conf_type];
+	if (cfg->have_new_ctrl) {
+		rdt_last_cmd_printf("Duplicate domain %d\n", d->hdr.id);
+		return -EINVAL;
+	}
+
+	if (!bw_validate(data->buf, &bw_val, r))
+		return -EINVAL;
+
+	if (is_mba_sc(r)) {
+		d->mbps_val[closid] = bw_val;
+		return 0;
+	}
+
+	cfg->new_ctrl = bw_val;
+	cfg->have_new_ctrl = true;
+
+	return 0;
+}
+
+/*
+ * Check whether a cache bit mask is valid.
+ * On Intel CPUs, non-contiguous 1s value support is indicated by CPUID:
+ *   - CPUID.0x10.1:ECX[3]: L3 non-contiguous 1s value supported if 1
+ *   - CPUID.0x10.2:ECX[3]: L2 non-contiguous 1s value supported if 1
+ *
+ * Haswell does not support a non-contiguous 1s value and additionally
+ * requires at least two bits set.
+ * AMD allows non-contiguous bitmasks.
+ */
+static bool cbm_validate(char *buf, u32 *data, struct rdt_resource *r)
+{
+	u32 supported_bits = BIT_MASK(r->cache.cbm_len) - 1;
+	unsigned int cbm_len = r->cache.cbm_len;
+	unsigned long first_bit, zero_bit, val;
+	int ret;
+
+	ret = kstrtoul(buf, 16, &val);
+	if (ret) {
+		rdt_last_cmd_printf("Non-hex character in the mask %s\n", buf);
+		return false;
+	}
+
+	if ((r->cache.min_cbm_bits > 0 && val == 0) || val > supported_bits) {
+		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);
+
+	/* Are non-contiguous bitmasks allowed? */
+	if (!r->cache.arch_has_sparse_bitmasks &&
+	    (find_next_bit(&val, cbm_len, zero_bit) < cbm_len)) {
+		rdt_last_cmd_printf("The 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 the 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.
+ */
+static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
+		     struct rdt_ctrl_domain *d)
+{
+	enum rdtgrp_mode mode = data->mode;
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	u32 closid = data->closid;
+	u32 cbm_val;
+
+	cfg = &d->staged_config[s->conf_type];
+	if (cfg->have_new_ctrl) {
+		rdt_last_cmd_printf("Duplicate domain %d\n", d->hdr.id);
+		return -EINVAL;
+	}
+
+	/*
+	 * Cannot set up more than one pseudo-locked region in a cache
+	 * hierarchy.
+	 */
+	if (mode == RDT_MODE_PSEUDO_LOCKSETUP &&
+	    rdtgroup_pseudo_locked_in_hierarchy(d)) {
+		rdt_last_cmd_puts("Pseudo-locked region in hierarchy\n");
+		return -EINVAL;
+	}
+
+	if (!cbm_validate(data->buf, &cbm_val, r))
+		return -EINVAL;
+
+	if ((mode == RDT_MODE_EXCLUSIVE || mode == RDT_MODE_SHAREABLE) &&
+	    rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) {
+		rdt_last_cmd_puts("CBM overlaps with pseudo-locked region\n");
+		return -EINVAL;
+	}
+
+	/*
+	 * The CBM may not overlap with the CBM of another closid if
+	 * either is exclusive.
+	 */
+	if (rdtgroup_cbm_overlaps(s, d, cbm_val, closid, true)) {
+		rdt_last_cmd_puts("Overlaps with exclusive group\n");
+		return -EINVAL;
+	}
+
+	if (rdtgroup_cbm_overlaps(s, d, cbm_val, closid, false)) {
+		if (mode == RDT_MODE_EXCLUSIVE ||
+		    mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			rdt_last_cmd_puts("Overlaps with other group\n");
+			return -EINVAL;
+		}
+	}
+
+	cfg->new_ctrl = cbm_val;
+	cfg->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 resctrl_schema *s,
+		      struct rdtgroup *rdtgrp)
+{
+	enum resctrl_conf_type t = s->conf_type;
+	ctrlval_parser_t *parse_ctrlval = NULL;
+	struct resctrl_staged_config *cfg;
+	struct rdt_resource *r = s->res;
+	struct rdt_parse_data data;
+	struct rdt_ctrl_domain *d;
+	char *dom = NULL, *id;
+	unsigned long dom_id;
+
+	/* Walking r->domains, ensure it can't race with cpuhp */
+	lockdep_assert_cpus_held();
+
+	switch (r->schema_fmt) {
+	case RESCTRL_SCHEMA_BITMAP:
+		parse_ctrlval = &parse_cbm;
+		break;
+	case RESCTRL_SCHEMA_RANGE:
+		parse_ctrlval = &parse_bw;
+		break;
+	}
+
+	if (WARN_ON_ONCE(!parse_ctrlval))
+		return -EINVAL;
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
+	    (r->rid == RDT_RESOURCE_MBA || r->rid == RDT_RESOURCE_SMBA)) {
+		rdt_last_cmd_puts("Cannot pseudo-lock MBA resource\n");
+		return -EINVAL;
+	}
+
+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_rcu(d, &r->ctrl_domains, hdr.list, lockdep_is_cpus_held()) {
+		if (d->hdr.id == dom_id) {
+			data.buf = dom;
+			data.closid = rdtgrp->closid;
+			data.mode = rdtgrp->mode;
+			if (parse_ctrlval(&data, s, d))
+				return -EINVAL;
+			if (rdtgrp->mode ==  RDT_MODE_PSEUDO_LOCKSETUP) {
+				cfg = &d->staged_config[t];
+				/*
+				 * In pseudo-locking setup mode and just
+				 * parsed a valid CBM that should be
+				 * pseudo-locked. Only one locked region per
+				 * resource group and domain so just do
+				 * the required initialization for single
+				 * region and return.
+				 */
+				rdtgrp->plr->s = s;
+				rdtgrp->plr->d = d;
+				rdtgrp->plr->cbm = cfg->new_ctrl;
+				d->plr = rdtgrp->plr;
+				return 0;
+			}
+			goto next;
+		}
+	}
+	return -EINVAL;
+}
+
+static int rdtgroup_parse_resource(char *resname, char *tok,
+				   struct rdtgroup *rdtgrp)
+{
+	struct resctrl_schema *s;
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		if (!strcmp(resname, s->name) && rdtgrp->closid < s->num_closid)
+			return parse_line(tok, s, rdtgrp);
+	}
+	rdt_last_cmd_printf("Unknown or 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 resctrl_schema *s;
+	struct rdtgroup *rdtgrp;
+	struct rdt_resource *r;
+	char *tok, *resname;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n') {
+		rdt_last_cmd_puts("schemata: Invalid input\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	buf[nbytes - 1] = '\0';
+
+	/*
+	 * No changes to pseudo-locked region allowed. It has to be removed
+	 * and re-created instead.
+	 */
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+		ret = -EINVAL;
+		rdt_last_cmd_puts("Resource group is pseudo-locked\n");
+		goto out_unlock;
+	}
+
+	rdt_staged_configs_clear();
+
+	while ((tok = strsep(&buf, "\n")) != NULL) {
+		resname = strim(strsep(&tok, ":"));
+		if (!tok) {
+			rdt_last_cmd_puts("Missing ':'\n");
+			ret = -EINVAL;
+			goto out_clear_staged;
+		}
+		if (tok[0] == '\0') {
+			rdt_last_cmd_printf("Missing '%s' value\n", resname);
+			ret = -EINVAL;
+			goto out_clear_staged;
+		}
+		ret = rdtgroup_parse_resource(resname, tok, rdtgrp);
+		if (ret)
+			goto out_clear_staged;
+	}
+
+	list_for_each_entry(s, &resctrl_schema_all, list) {
+		r = s->res;
+
+		/*
+		 * Writes to mba_sc resources update the software controller,
+		 * not the control MSR.
+		 */
+		if (is_mba_sc(r))
+			continue;
+
+		ret = resctrl_arch_update_domains(r, rdtgrp->closid);
+		if (ret)
+			goto out_clear_staged;
+	}
+
+	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+		/*
+		 * If pseudo-locking fails we keep the resource group in
+		 * mode RDT_MODE_PSEUDO_LOCKSETUP with its class of service
+		 * active and updated for just the domain the pseudo-locked
+		 * region was requested for.
+		 */
+		ret = rdtgroup_pseudo_lock_create(rdtgrp);
+	}
+
+out_clear_staged:
+	rdt_staged_configs_clear();
+out_unlock:
+	rdtgroup_kn_unlock(of->kn);
+	return ret ?: nbytes;
+}
+
+static void show_doms(struct seq_file *s, struct resctrl_schema *schema,
+		      char *resource_name, int closid)
+{
+	struct rdt_resource *r = schema->res;
+	struct rdt_ctrl_domain *dom;
+	bool sep = false;
+	u32 ctrl_val;
+
+	/* Walking r->domains, ensure it can't race with cpuhp */
+	lockdep_assert_cpus_held();
+
+	if (resource_name)
+		seq_printf(s, "%*s:", max_name_width, resource_name);
+	list_for_each_entry_rcu(dom, &r->ctrl_domains, hdr.list, lockdep_is_cpus_held()) {
+		if (sep)
+			seq_puts(s, ";");
+
+		if (is_mba_sc(r))
+			ctrl_val = dom->mbps_val[closid];
+		else
+			ctrl_val = resctrl_arch_get_config(r, dom, closid,
+							   schema->conf_type);
+
+		seq_printf(s, schema->fmt_str, dom->hdr.id, ctrl_val);
+		sep = true;
+	}
+	seq_puts(s, "\n");
+}
+
+int rdtgroup_schemata_show(struct kernfs_open_file *of,
+			   struct seq_file *s, void *v)
+{
+	struct resctrl_schema *schema;
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+	u32 closid;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (rdtgrp) {
+		if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
+			list_for_each_entry(schema, &resctrl_schema_all, list) {
+				seq_printf(s, "%s:uninitialized\n", schema->name);
+			}
+		} else if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+			if (!rdtgrp->plr->d) {
+				rdt_last_cmd_puts("Cache domain offline\n");
+				ret = -ENODEV;
+			} else {
+				seq_printf(s, "%s:%d=%x\n",
+					   rdtgrp->plr->s->res->name,
+					   rdtgrp->plr->d->hdr.id,
+					   rdtgrp->plr->cbm);
+			}
+		} else {
+			closid = rdtgrp->closid;
+			list_for_each_entry(schema, &resctrl_schema_all, list) {
+				if (closid < schema->num_closid)
+					show_doms(s, schema, schema->name, closid);
+			}
+		}
+	} else {
+		ret = -ENOENT;
+	}
+	rdtgroup_kn_unlock(of->kn);
+	return ret;
+}
+
+static int smp_mon_event_count(void *arg)
+{
+	mon_event_count(arg);
+
+	return 0;
+}
+
+ssize_t rdtgroup_mba_mbps_event_write(struct kernfs_open_file *of,
+				      char *buf, size_t nbytes, loff_t off)
+{
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		rdtgroup_kn_unlock(of->kn);
+		return -ENOENT;
+	}
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n') {
+		rdt_last_cmd_puts("mba_MBps_event: Invalid input\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	buf[nbytes - 1] = '\0';
+
+	if (!strcmp(buf, "mbm_local_bytes")) {
+		if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID))
+			rdtgrp->mba_mbps_event = QOS_L3_MBM_LOCAL_EVENT_ID;
+		else
+			ret = -EINVAL;
+	} else if (!strcmp(buf, "mbm_total_bytes")) {
+		if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID))
+			rdtgrp->mba_mbps_event = QOS_L3_MBM_TOTAL_EVENT_ID;
+		else
+			ret = -EINVAL;
+	} else {
+		ret = -EINVAL;
+	}
+
+	if (ret)
+		rdt_last_cmd_printf("Unsupported event id '%s'\n", buf);
+
+out_unlock:
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret ?: nbytes;
+}
+
+int rdtgroup_mba_mbps_event_show(struct kernfs_open_file *of,
+				 struct seq_file *s, void *v)
+{
+	struct rdtgroup *rdtgrp;
+	int ret = 0;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+
+	if (rdtgrp) {
+		switch (rdtgrp->mba_mbps_event) {
+		case QOS_L3_MBM_LOCAL_EVENT_ID:
+			seq_puts(s, "mbm_local_bytes\n");
+			break;
+		case QOS_L3_MBM_TOTAL_EVENT_ID:
+			seq_puts(s, "mbm_total_bytes\n");
+			break;
+		default:
+			pr_warn_once("Bad event %d\n", rdtgrp->mba_mbps_event);
+			ret = -EINVAL;
+			break;
+		}
+	} else {
+		ret = -ENOENT;
+	}
+
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret;
+}
+
+struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
+					   struct list_head **pos)
+{
+	struct rdt_domain_hdr *d;
+	struct list_head *l;
+
+	lockdep_assert_cpus_held();
+
+	list_for_each(l, h) {
+		d = list_entry(l, struct rdt_domain_hdr, list);
+		/* When id is found, return its domain. */
+		if (id == d->id)
+			return d;
+		/* Stop searching when finding id's position in sorted list. */
+		if (id < d->id)
+			break;
+	}
+
+	if (pos)
+		*pos = l;
+
+	return NULL;
+}
+
+void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
+		    struct rdt_domain_hdr *hdr, struct rdtgroup *rdtgrp,
+		    cpumask_t *cpumask, struct mon_evt *evt, int first)
+{
+	int cpu;
+
+	/* When picking a CPU from cpu_mask, ensure it can't race with cpuhp */
+	lockdep_assert_cpus_held();
+
+	/*
+	 * Setup the parameters to pass to mon_event_count() to read the data.
+	 */
+	rr->rgrp = rdtgrp;
+	rr->evt = evt;
+	rr->r = r;
+	rr->hdr = hdr;
+	rr->first = first;
+	if (resctrl_arch_mbm_cntr_assign_enabled(r) &&
+	    resctrl_is_mbm_event(evt->evtid)) {
+		rr->is_mbm_cntr = true;
+	} else {
+		rr->arch_mon_ctx = resctrl_arch_mon_ctx_alloc(r, evt->evtid);
+		if (IS_ERR(rr->arch_mon_ctx)) {
+			rr->err = -EINVAL;
+			return;
+		}
+	}
+
+	if (evt->any_cpu) {
+		mon_event_count(rr);
+		goto out_ctx_free;
+	}
+
+	cpu = cpumask_any_housekeeping(cpumask, RESCTRL_PICK_ANY_CPU);
+
+	/*
+	 * cpumask_any_housekeeping() prefers housekeeping CPUs, but
+	 * are all the CPUs nohz_full? If yes, pick a CPU to IPI.
+	 * MPAM's resctrl_arch_rmid_read() is unable to read the
+	 * counters on some platforms if its called in IRQ context.
+	 */
+	if (tick_nohz_full_cpu(cpu))
+		smp_call_function_any(cpumask, mon_event_count, rr, 1);
+	else
+		smp_call_on_cpu(cpu, smp_mon_event_count, rr, false);
+
+out_ctx_free:
+	if (rr->arch_mon_ctx)
+		resctrl_arch_mon_ctx_free(r, evt->evtid, rr->arch_mon_ctx);
+}
+
+/*
+ * Decimal place precision to use for each number of fixed-point
+ * binary bits computed from ceil(binary_bits * log10(2)) except
+ * binary_bits == 0 which will print "value.0"
+ */
+static const unsigned int decplaces[MAX_BINARY_BITS + 1] = {
+	[0]  =  1,
+	[1]  =  1,
+	[2]  =  1,
+	[3]  =  1,
+	[4]  =  2,
+	[5]  =  2,
+	[6]  =  2,
+	[7]  =  3,
+	[8]  =  3,
+	[9]  =  3,
+	[10] =  4,
+	[11] =  4,
+	[12] =  4,
+	[13] =  4,
+	[14] =  5,
+	[15] =  5,
+	[16] =  5,
+	[17] =  6,
+	[18] =  6,
+	[19] =  6,
+	[20] =  7,
+	[21] =  7,
+	[22] =  7,
+	[23] =  7,
+	[24] =  8,
+	[25] =  8,
+	[26] =  8,
+	[27] =  9
+};
+
+static void print_event_value(struct seq_file *m, unsigned int binary_bits, u64 val)
+{
+	unsigned long long frac = 0;
+
+	if (binary_bits) {
+		/* Mask off the integer part of the fixed-point value. */
+		frac = val & GENMASK_ULL(binary_bits - 1, 0);
+
+		/*
+		 * Multiply by 10^{desired decimal places}. The integer part of
+		 * the fixed point value is now almost what is needed.
+		 */
+		frac *= int_pow(10ull, decplaces[binary_bits]);
+
+		/*
+		 * Round to nearest by adding a value that would be a "1" in the
+		 * binary_bits + 1 place.  Integer part of fixed point value is
+		 * now the needed value.
+		 */
+		frac += 1ull << (binary_bits - 1);
+
+		/*
+		 * Extract the integer part of the value. This is the decimal
+		 * representation of the original fixed-point fractional value.
+		 */
+		frac >>= binary_bits;
+	}
+
+	/*
+	 * "frac" is now in the range [0 .. 10^decplaces).  I.e. string
+	 * representation will fit into chosen number of decimal places.
+	 */
+	seq_printf(m, "%llu.%0*llu\n", val >> binary_bits, decplaces[binary_bits], frac);
+}
+
+int rdtgroup_mondata_show(struct seq_file *m, void *arg)
+{
+	struct kernfs_open_file *of = m->private;
+	enum resctrl_res_level resid;
+	struct rdt_domain_hdr *hdr;
+	struct rmid_read rr = {0};
+	struct rdtgroup *rdtgrp;
+	int domid, cpu, ret = 0;
+	struct rdt_resource *r;
+	struct cacheinfo *ci;
+	struct mon_evt *evt;
+	struct mon_data *md;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		ret = -ENOENT;
+		goto out;
+	}
+
+	md = of->kn->priv;
+	if (WARN_ON_ONCE(!md)) {
+		ret = -EIO;
+		goto out;
+	}
+
+	resid = md->rid;
+	domid = md->domid;
+	evt = md->evt;
+	r = resctrl_arch_get_resource(resid);
+
+	if (md->sum) {
+		struct rdt_l3_mon_domain *d;
+
+		if (WARN_ON_ONCE(resid != RDT_RESOURCE_L3)) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		/*
+		 * This file requires summing across all domains that share
+		 * the L3 cache id that was provided in the "domid" field of the
+		 * struct mon_data. Search all domains in the resource for
+		 * one that matches this cache id.
+		 */
+		list_for_each_entry_rcu(d, &r->mon_domains, hdr.list, lockdep_is_cpus_held()) {
+			if (d->ci_id == domid) {
+				cpu = cpumask_any(&d->hdr.cpu_mask);
+				ci = get_cpu_cacheinfo_level(cpu, RESCTRL_L3_CACHE);
+				if (!ci)
+					continue;
+				rr.ci = ci;
+				mon_event_read(&rr, r, NULL, rdtgrp,
+					       &ci->shared_cpu_map, evt, false);
+				goto checkresult;
+			}
+		}
+		ret = -ENOENT;
+		goto out;
+	} else {
+		/*
+		 * This file provides data from a single domain. Search
+		 * the resource to find the domain with "domid".
+		 */
+		hdr = resctrl_find_domain(&r->mon_domains, domid, NULL);
+		if (!hdr) {
+			ret = -ENOENT;
+			goto out;
+		}
+		mon_event_read(&rr, r, hdr, rdtgrp, &hdr->cpu_mask, evt, false);
+	}
+
+checkresult:
+
+	/*
+	 * -ENOENT is a special case, set only when "mbm_event" counter assignment
+	 * mode is enabled and no counter has been assigned.
+	 */
+	if (rr.err == -EIO)
+		seq_puts(m, "Error\n");
+	else if (rr.err == -EINVAL)
+		seq_puts(m, "Unavailable\n");
+	else if (rr.err == -ENOENT)
+		seq_puts(m, "Unassigned\n");
+	else if (evt->is_floating_point)
+		print_event_value(m, evt->binary_bits, rr.val);
+	else
+		seq_printf(m, "%llu\n", rr.val);
+
+out:
+	rdtgroup_kn_unlock(of->kn);
+	return ret;
+}
+
+int resctrl_io_alloc_show(struct kernfs_open_file *of, struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
+	struct rdt_resource *r;
+
+	if (!info_kn_lock(of->kn))
+		return -ENOENT;
+
+	r = s->res;
+	if (r->cache.io_alloc_capable) {
+		if (resctrl_arch_get_io_alloc_enabled(r))
+			seq_puts(seq, "enabled\n");
+		else
+			seq_puts(seq, "disabled\n");
+	} else {
+		seq_puts(seq, "not supported\n");
+	}
+
+	info_kn_unlock(of->kn);
+
+	return 0;
+}
+
+/*
+ * resctrl_io_alloc_closid_supported() - io_alloc feature utilizes the
+ * highest CLOSID value to direct I/O traffic. Ensure that io_alloc_closid
+ * is in the supported range.
+ */
+static bool resctrl_io_alloc_closid_supported(u32 io_alloc_closid)
+{
+	return io_alloc_closid < closids_supported();
+}
+
+/*
+ * Initialize io_alloc CLOSID cache resource CBM with all usable (shared
+ * and unused) cache portions.
+ */
+static int resctrl_io_alloc_init_cbm(struct resctrl_schema *s, u32 closid)
+{
+	enum resctrl_conf_type peer_type;
+	struct rdt_resource *r = s->res;
+	struct rdt_ctrl_domain *d;
+	int ret;
+
+	rdt_staged_configs_clear();
+
+	ret = rdtgroup_init_cat(s, closid);
+	if (ret < 0)
+		goto out;
+
+	/* Keep CDP_CODE and CDP_DATA of io_alloc CLOSID's CBM in sync. */
+	if (resctrl_arch_get_cdp_enabled(r->rid)) {
+		peer_type = resctrl_peer_type(s->conf_type);
+		list_for_each_entry_rcu(d, &s->res->ctrl_domains, hdr.list, lockdep_is_cpus_held())
+			memcpy(&d->staged_config[peer_type],
+			       &d->staged_config[s->conf_type],
+			       sizeof(d->staged_config[0]));
+	}
+
+	ret = resctrl_arch_update_domains(r, closid);
+out:
+	rdt_staged_configs_clear();
+	return ret;
+}
+
+/*
+ * resctrl_io_alloc_closid() - io_alloc feature routes I/O traffic using
+ * the highest available CLOSID. Retrieve the maximum CLOSID supported by the
+ * resource. Note that if Code Data Prioritization (CDP) is enabled, the number
+ * of available CLOSIDs is reduced by half.
+ */
+u32 resctrl_io_alloc_closid(struct rdt_resource *r)
+{
+	if (resctrl_arch_get_cdp_enabled(r->rid))
+		return resctrl_arch_get_num_closid(r) / 2  - 1;
+	else
+		return resctrl_arch_get_num_closid(r) - 1;
+}
+
+ssize_t resctrl_io_alloc_write(struct kernfs_open_file *of, char *buf,
+			       size_t nbytes, loff_t off)
+{
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
+	struct rdt_resource *r;
+	char const *grp_name;
+	u32 io_alloc_closid;
+	bool enable;
+	int ret;
+
+	if (!info_kn_lock(of->kn))
+		return -ENOENT;
+
+	r = s->res;
+	rdt_last_cmd_clear();
+
+	ret = kstrtobool(buf, &enable);
+	if (ret) {
+		rdt_last_cmd_puts("io_alloc: Invalid input\n");
+		goto out_unlock;
+	}
+
+	if (!r->cache.io_alloc_capable) {
+		rdt_last_cmd_printf("io_alloc is not supported on %s\n", s->name);
+		ret = -ENODEV;
+		goto out_unlock;
+	}
+
+	/* If the feature is already up to date, no action is needed. */
+	if (resctrl_arch_get_io_alloc_enabled(r) == enable)
+		goto out_unlock;
+
+	io_alloc_closid = resctrl_io_alloc_closid(r);
+	if (!resctrl_io_alloc_closid_supported(io_alloc_closid)) {
+		rdt_last_cmd_printf("io_alloc CLOSID (ctrl_hw_id) %u is not available\n",
+				    io_alloc_closid);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	if (enable) {
+		if (!closid_alloc_fixed(io_alloc_closid)) {
+			grp_name = rdtgroup_name_by_closid(io_alloc_closid);
+			WARN_ON_ONCE(!grp_name);
+			rdt_last_cmd_printf("CLOSID (ctrl_hw_id) %u for io_alloc is used by %s group\n",
+					    io_alloc_closid, grp_name ? grp_name : "another");
+			ret = -ENOSPC;
+			goto out_unlock;
+		}
+
+		ret = resctrl_io_alloc_init_cbm(s, io_alloc_closid);
+		if (ret) {
+			rdt_last_cmd_puts("Failed to initialize io_alloc allocations\n");
+			closid_free(io_alloc_closid);
+			goto out_unlock;
+		}
+	} else {
+		closid_free(io_alloc_closid);
+	}
+
+	ret = resctrl_arch_io_alloc_enable(r, enable);
+	if (enable && ret) {
+		rdt_last_cmd_puts("Failed to enable io_alloc feature\n");
+		closid_free(io_alloc_closid);
+	}
+
+out_unlock:
+	info_kn_unlock(of->kn);
+
+	return ret ?: nbytes;
+}
+
+int resctrl_io_alloc_cbm_show(struct kernfs_open_file *of, struct seq_file *seq, void *v)
+{
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
+	struct rdt_resource *r;
+	int ret = 0;
+
+	if (!info_kn_lock(of->kn))
+		return -ENOENT;
+
+	rdt_last_cmd_clear();
+
+	r = s->res;
+	if (!r->cache.io_alloc_capable) {
+		rdt_last_cmd_printf("io_alloc is not supported on %s\n", s->name);
+		ret = -ENODEV;
+		goto out_unlock;
+	}
+
+	if (!resctrl_arch_get_io_alloc_enabled(r)) {
+		rdt_last_cmd_printf("io_alloc is not enabled on %s\n", s->name);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	/*
+	 * When CDP is enabled, the CBMs of the highest CLOSID of CDP_CODE and
+	 * CDP_DATA are kept in sync. As a result, the io_alloc CBMs shown for
+	 * either CDP resource are identical and accurately represent the CBMs
+	 * used for I/O.
+	 */
+	show_doms(seq, s, NULL, resctrl_io_alloc_closid(r));
+
+out_unlock:
+	info_kn_unlock(of->kn);
+	return ret;
+}
+
+static int resctrl_io_alloc_parse_line(char *line,  struct rdt_resource *r,
+				       struct resctrl_schema *s, u32 closid)
+{
+	enum resctrl_conf_type peer_type;
+	unsigned long dom_id = ULONG_MAX;
+	struct rdt_parse_data data;
+	struct rdt_ctrl_domain *d;
+	bool update_all = false;
+	char *dom = NULL, *id;
+
+next:
+	if (!line || line[0] == '\0')
+		return 0;
+
+	if (update_all) {
+		rdt_last_cmd_puts("Configurations after global '*'\n");
+		return -EINVAL;
+	}
+
+	dom = strsep(&line, ";");
+	id = strsep(&dom, "=");
+
+	if (dom && !strcmp(id, "*")) {
+		update_all = true;
+	} else 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_rcu(d, &r->ctrl_domains, hdr.list, lockdep_is_cpus_held()) {
+		if (update_all || d->hdr.id == dom_id) {
+			data.buf = dom;
+			data.mode = RDT_MODE_SHAREABLE;
+			data.closid = closid;
+			if (parse_cbm(&data, s, d))
+				return -EINVAL;
+			/*
+			 * Keep io_alloc CLOSID's CBM of CDP_CODE and CDP_DATA
+			 * in sync.
+			 */
+			if (resctrl_arch_get_cdp_enabled(r->rid)) {
+				peer_type = resctrl_peer_type(s->conf_type);
+				memcpy(&d->staged_config[peer_type],
+				       &d->staged_config[s->conf_type],
+				       sizeof(d->staged_config[0]));
+			}
+			if (!update_all)
+				goto next;
+		}
+	}
+
+	if (update_all)
+		goto next;
+
+	rdt_last_cmd_printf("Invalid domain %lu\n", dom_id);
+	return -EINVAL;
+}
+
+ssize_t resctrl_io_alloc_cbm_write(struct kernfs_open_file *of, char *buf,
+				   size_t nbytes, loff_t off)
+{
+	struct resctrl_schema *s = rdt_kn_parent_priv(of->kn);
+	struct rdt_resource *r;
+	u32 io_alloc_closid;
+	int ret = 0;
+
+	if (!info_kn_lock(of->kn))
+		return -ENOENT;
+	rdt_last_cmd_clear();
+
+	r = s->res;
+
+	/* Valid input requires a trailing newline */
+	if (nbytes == 0 || buf[nbytes - 1] != '\n') {
+		rdt_last_cmd_puts("io_alloc_cbm: Invalid input\n");
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	buf[nbytes - 1] = '\0';
+
+	if (!r->cache.io_alloc_capable) {
+		rdt_last_cmd_printf("io_alloc is not supported on %s\n", s->name);
+		ret = -ENODEV;
+		goto out_unlock;
+	}
+
+	if (!resctrl_arch_get_io_alloc_enabled(r)) {
+		rdt_last_cmd_printf("io_alloc is not enabled on %s\n", s->name);
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+
+	io_alloc_closid = resctrl_io_alloc_closid(r);
+
+	rdt_staged_configs_clear();
+	ret = resctrl_io_alloc_parse_line(buf, r, s, io_alloc_closid);
+	if (ret)
+		goto out_clear_configs;
+
+	ret = resctrl_arch_update_domains(r, io_alloc_closid);
+
+out_clear_configs:
+	rdt_staged_configs_clear();
+out_unlock:
+	info_kn_unlock(of->kn);
+
+	return ret ?: nbytes;
+}