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Diffstat (limited to 'arch/x86/kernel/cpu/intel_rdt_rdtgroup.c')
-rw-r--r--arch/x86/kernel/cpu/intel_rdt_rdtgroup.c263
1 files changed, 226 insertions, 37 deletions
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index b799c00bef09..f27b8115ffa2 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -97,6 +97,12 @@ void rdt_last_cmd_printf(const char *fmt, ...)
* limited as the number of resources grows.
*/
static int closid_free_map;
+static int closid_free_map_len;
+
+int closids_supported(void)
+{
+ return closid_free_map_len;
+}
static void closid_init(void)
{
@@ -111,6 +117,7 @@ static void closid_init(void)
/* CLOSID 0 is always reserved for the default group */
closid_free_map &= ~1;
+ closid_free_map_len = rdt_min_closid;
}
static int closid_alloc(void)
@@ -261,17 +268,27 @@ static int rdtgroup_cpus_show(struct kernfs_open_file *of,
struct seq_file *s, void *v)
{
struct rdtgroup *rdtgrp;
+ struct cpumask *mask;
int ret = 0;
rdtgrp = rdtgroup_kn_lock_live(of->kn);
if (rdtgrp) {
- if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED)
- seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n",
- cpumask_pr_args(&rdtgrp->plr->d->cpu_mask));
- else
+ if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
+ if (!rdtgrp->plr->d) {
+ rdt_last_cmd_clear();
+ rdt_last_cmd_puts("Cache domain offline\n");
+ ret = -ENODEV;
+ } else {
+ mask = &rdtgrp->plr->d->cpu_mask;
+ seq_printf(s, is_cpu_list(of) ?
+ "%*pbl\n" : "%*pb\n",
+ cpumask_pr_args(mask));
+ }
+ } else {
seq_printf(s, is_cpu_list(of) ? "%*pbl\n" : "%*pb\n",
cpumask_pr_args(&rdtgrp->cpu_mask));
+ }
} else {
ret = -ENOENT;
}
@@ -802,7 +819,7 @@ static int rdt_bit_usage_show(struct kernfs_open_file *of,
sw_shareable = 0;
exclusive = 0;
seq_printf(seq, "%d=", dom->id);
- for (i = 0; i < r->num_closid; i++, ctrl++) {
+ for (i = 0; i < closids_supported(); i++, ctrl++) {
if (!closid_allocated(i))
continue;
mode = rdtgroup_mode_by_closid(i);
@@ -954,7 +971,78 @@ static int rdtgroup_mode_show(struct kernfs_open_file *of,
}
/**
- * rdtgroup_cbm_overlaps - Does CBM for intended closid overlap with other
+ * rdt_cdp_peer_get - Retrieve CDP peer if it exists
+ * @r: RDT resource to which RDT domain @d belongs
+ * @d: Cache instance for which a CDP peer is requested
+ * @r_cdp: RDT resource that shares hardware with @r (RDT resource peer)
+ * Used to return the result.
+ * @d_cdp: RDT domain that shares hardware with @d (RDT domain peer)
+ * Used to return the result.
+ *
+ * RDT resources are managed independently and by extension the RDT domains
+ * (RDT resource instances) are managed independently also. The Code and
+ * Data Prioritization (CDP) RDT resources, while managed independently,
+ * could refer to the same underlying hardware. For example,
+ * RDT_RESOURCE_L2CODE and RDT_RESOURCE_L2DATA both refer to the L2 cache.
+ *
+ * When provided with an RDT resource @r and an instance of that RDT
+ * resource @d rdt_cdp_peer_get() will return if there is a peer RDT
+ * resource and the exact instance that shares the same hardware.
+ *
+ * Return: 0 if a CDP peer was found, <0 on error or if no CDP peer exists.
+ * If a CDP peer was found, @r_cdp will point to the peer RDT resource
+ * and @d_cdp will point to the peer RDT domain.
+ */
+static int rdt_cdp_peer_get(struct rdt_resource *r, struct rdt_domain *d,
+ struct rdt_resource **r_cdp,
+ struct rdt_domain **d_cdp)
+{
+ struct rdt_resource *_r_cdp = NULL;
+ struct rdt_domain *_d_cdp = NULL;
+ int ret = 0;
+
+ switch (r->rid) {
+ case RDT_RESOURCE_L3DATA:
+ _r_cdp = &rdt_resources_all[RDT_RESOURCE_L3CODE];
+ break;
+ case RDT_RESOURCE_L3CODE:
+ _r_cdp = &rdt_resources_all[RDT_RESOURCE_L3DATA];
+ break;
+ case RDT_RESOURCE_L2DATA:
+ _r_cdp = &rdt_resources_all[RDT_RESOURCE_L2CODE];
+ break;
+ case RDT_RESOURCE_L2CODE:
+ _r_cdp = &rdt_resources_all[RDT_RESOURCE_L2DATA];
+ break;
+ default:
+ ret = -ENOENT;
+ goto out;
+ }
+
+ /*
+ * When a new CPU comes online and CDP is enabled then the new
+ * RDT domains (if any) associated with both CDP RDT resources
+ * are added in the same CPU online routine while the
+ * rdtgroup_mutex is held. It should thus not happen for one
+ * RDT domain to exist and be associated with its RDT CDP
+ * resource but there is no RDT domain associated with the
+ * peer RDT CDP resource. Hence the WARN.
+ */
+ _d_cdp = rdt_find_domain(_r_cdp, d->id, NULL);
+ if (WARN_ON(!_d_cdp)) {
+ _r_cdp = NULL;
+ ret = -EINVAL;
+ }
+
+out:
+ *r_cdp = _r_cdp;
+ *d_cdp = _d_cdp;
+
+ return ret;
+}
+
+/**
+ * __rdtgroup_cbm_overlaps - Does CBM for intended closid overlap with other
* @r: Resource to which domain instance @d belongs.
* @d: The domain instance for which @closid is being tested.
* @cbm: Capacity bitmask being tested.
@@ -968,33 +1056,34 @@ static int rdtgroup_mode_show(struct kernfs_open_file *of,
* is false then overlaps with any resource group or hardware entities
* will be considered.
*
+ * @cbm is unsigned long, even if only 32 bits are used, to make the
+ * bitmap functions work correctly.
+ *
* Return: false if CBM does not overlap, true if it does.
*/
-bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
- u32 _cbm, int closid, bool exclusive)
+static bool __rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
+ unsigned long cbm, int closid, bool exclusive)
{
- unsigned long *cbm = (unsigned long *)&_cbm;
- unsigned long *ctrl_b;
enum rdtgrp_mode mode;
+ unsigned long ctrl_b;
u32 *ctrl;
int i;
/* Check for any overlap with regions used by hardware directly */
if (!exclusive) {
- if (bitmap_intersects(cbm,
- (unsigned long *)&r->cache.shareable_bits,
- r->cache.cbm_len))
+ ctrl_b = r->cache.shareable_bits;
+ if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len))
return true;
}
/* Check for overlap with other resource groups */
ctrl = d->ctrl_val;
- for (i = 0; i < r->num_closid; i++, ctrl++) {
- ctrl_b = (unsigned long *)ctrl;
+ for (i = 0; i < closids_supported(); i++, ctrl++) {
+ ctrl_b = *ctrl;
mode = rdtgroup_mode_by_closid(i);
if (closid_allocated(i) && i != closid &&
mode != RDT_MODE_PSEUDO_LOCKSETUP) {
- if (bitmap_intersects(cbm, ctrl_b, r->cache.cbm_len)) {
+ if (bitmap_intersects(&cbm, &ctrl_b, r->cache.cbm_len)) {
if (exclusive) {
if (mode == RDT_MODE_EXCLUSIVE)
return true;
@@ -1009,6 +1098,41 @@ bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
}
/**
+ * rdtgroup_cbm_overlaps - Does CBM overlap with other use of hardware
+ * @r: Resource to which domain instance @d belongs.
+ * @d: The domain instance for which @closid is being tested.
+ * @cbm: Capacity bitmask being tested.
+ * @closid: Intended closid for @cbm.
+ * @exclusive: Only check if overlaps with exclusive resource groups
+ *
+ * Resources that can be allocated using a CBM can use the CBM to control
+ * the overlap of these allocations. rdtgroup_cmb_overlaps() is the test
+ * for overlap. Overlap test is not limited to the specific resource for
+ * which the CBM is intended though - when dealing with CDP resources that
+ * share the underlying hardware the overlap check should be performed on
+ * the CDP resource sharing the hardware also.
+ *
+ * Refer to description of __rdtgroup_cbm_overlaps() for the details of the
+ * overlap test.
+ *
+ * Return: true if CBM overlap detected, false if there is no overlap
+ */
+bool rdtgroup_cbm_overlaps(struct rdt_resource *r, struct rdt_domain *d,
+ unsigned long cbm, int closid, bool exclusive)
+{
+ struct rdt_resource *r_cdp;
+ struct rdt_domain *d_cdp;
+
+ if (__rdtgroup_cbm_overlaps(r, d, cbm, closid, exclusive))
+ return true;
+
+ if (rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp) < 0)
+ return false;
+
+ return __rdtgroup_cbm_overlaps(r_cdp, d_cdp, cbm, closid, exclusive);
+}
+
+/**
* rdtgroup_mode_test_exclusive - Test if this resource group can be exclusive
*
* An exclusive resource group implies that there should be no sharing of
@@ -1024,16 +1148,27 @@ static bool rdtgroup_mode_test_exclusive(struct rdtgroup *rdtgrp)
{
int closid = rdtgrp->closid;
struct rdt_resource *r;
+ bool has_cache = false;
struct rdt_domain *d;
for_each_alloc_enabled_rdt_resource(r) {
+ if (r->rid == RDT_RESOURCE_MBA)
+ continue;
+ has_cache = true;
list_for_each_entry(d, &r->domains, list) {
if (rdtgroup_cbm_overlaps(r, d, d->ctrl_val[closid],
- rdtgrp->closid, false))
+ rdtgrp->closid, false)) {
+ rdt_last_cmd_puts("schemata overlaps\n");
return false;
+ }
}
}
+ if (!has_cache) {
+ rdt_last_cmd_puts("cannot be exclusive without CAT/CDP\n");
+ return false;
+ }
+
return true;
}
@@ -1085,7 +1220,6 @@ static ssize_t rdtgroup_mode_write(struct kernfs_open_file *of,
rdtgrp->mode = RDT_MODE_SHAREABLE;
} else if (!strcmp(buf, "exclusive")) {
if (!rdtgroup_mode_test_exclusive(rdtgrp)) {
- rdt_last_cmd_printf("schemata overlaps\n");
ret = -EINVAL;
goto out;
}
@@ -1121,15 +1255,18 @@ out:
* computed by first dividing the total cache size by the CBM length to
* determine how many bytes each bit in the bitmask represents. The result
* is multiplied with the number of bits set in the bitmask.
+ *
+ * @cbm is unsigned long, even if only 32 bits are used to make the
+ * bitmap functions work correctly.
*/
unsigned int rdtgroup_cbm_to_size(struct rdt_resource *r,
- struct rdt_domain *d, u32 cbm)
+ struct rdt_domain *d, unsigned long cbm)
{
struct cpu_cacheinfo *ci;
unsigned int size = 0;
int num_b, i;
- num_b = bitmap_weight((unsigned long *)&cbm, r->cache.cbm_len);
+ num_b = bitmap_weight(&cbm, r->cache.cbm_len);
ci = get_cpu_cacheinfo(cpumask_any(&d->cpu_mask));
for (i = 0; i < ci->num_leaves; i++) {
if (ci->info_list[i].level == r->cache_level) {
@@ -1155,8 +1292,9 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
struct rdt_resource *r;
struct rdt_domain *d;
unsigned int size;
- bool sep = false;
- u32 cbm;
+ int ret = 0;
+ bool sep;
+ u32 ctrl;
rdtgrp = rdtgroup_kn_lock_live(of->kn);
if (!rdtgrp) {
@@ -1165,15 +1303,23 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
}
if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKED) {
- seq_printf(s, "%*s:", max_name_width, rdtgrp->plr->r->name);
- size = rdtgroup_cbm_to_size(rdtgrp->plr->r,
- rdtgrp->plr->d,
- rdtgrp->plr->cbm);
- seq_printf(s, "%d=%u\n", rdtgrp->plr->d->id, size);
+ if (!rdtgrp->plr->d) {
+ rdt_last_cmd_clear();
+ rdt_last_cmd_puts("Cache domain offline\n");
+ ret = -ENODEV;
+ } else {
+ seq_printf(s, "%*s:", max_name_width,
+ rdtgrp->plr->r->name);
+ size = rdtgroup_cbm_to_size(rdtgrp->plr->r,
+ rdtgrp->plr->d,
+ rdtgrp->plr->cbm);
+ seq_printf(s, "%d=%u\n", rdtgrp->plr->d->id, size);
+ }
goto out;
}
for_each_alloc_enabled_rdt_resource(r) {
+ sep = false;
seq_printf(s, "%*s:", max_name_width, r->name);
list_for_each_entry(d, &r->domains, list) {
if (sep)
@@ -1181,8 +1327,13 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP) {
size = 0;
} else {
- cbm = d->ctrl_val[rdtgrp->closid];
- size = rdtgroup_cbm_to_size(r, d, cbm);
+ ctrl = (!is_mba_sc(r) ?
+ d->ctrl_val[rdtgrp->closid] :
+ d->mbps_val[rdtgrp->closid]);
+ if (r->rid == RDT_RESOURCE_MBA)
+ size = ctrl;
+ else
+ size = rdtgroup_cbm_to_size(r, d, ctrl);
}
seq_printf(s, "%d=%u", d->id, size);
sep = true;
@@ -1193,7 +1344,7 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
out:
rdtgroup_kn_unlock(of->kn);
- return 0;
+ return ret;
}
/* rdtgroup information files for one cache resource. */
@@ -2327,28 +2478,48 @@ static void cbm_ensure_valid(u32 *_val, struct rdt_resource *r)
*/
static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
{
+ struct rdt_resource *r_cdp = NULL;
+ struct rdt_domain *d_cdp = NULL;
u32 used_b = 0, unused_b = 0;
u32 closid = rdtgrp->closid;
struct rdt_resource *r;
+ unsigned long tmp_cbm;
enum rdtgrp_mode mode;
struct rdt_domain *d;
+ u32 peer_ctl, *ctrl;
int i, ret;
- u32 *ctrl;
for_each_alloc_enabled_rdt_resource(r) {
+ /*
+ * Only initialize default allocations for CBM cache
+ * resources
+ */
+ if (r->rid == RDT_RESOURCE_MBA)
+ continue;
list_for_each_entry(d, &r->domains, list) {
+ rdt_cdp_peer_get(r, d, &r_cdp, &d_cdp);
d->have_new_ctrl = false;
d->new_ctrl = r->cache.shareable_bits;
used_b = r->cache.shareable_bits;
ctrl = d->ctrl_val;
- for (i = 0; i < r->num_closid; i++, ctrl++) {
+ for (i = 0; i < closids_supported(); i++, ctrl++) {
if (closid_allocated(i) && i != closid) {
mode = rdtgroup_mode_by_closid(i);
if (mode == RDT_MODE_PSEUDO_LOCKSETUP)
break;
- used_b |= *ctrl;
+ /*
+ * If CDP is active include peer
+ * domain's usage to ensure there
+ * is no overlap with an exclusive
+ * group.
+ */
+ if (d_cdp)
+ peer_ctl = d_cdp->ctrl_val[i];
+ else
+ peer_ctl = 0;
+ used_b |= *ctrl | peer_ctl;
if (mode == RDT_MODE_SHAREABLE)
- d->new_ctrl |= *ctrl;
+ d->new_ctrl |= *ctrl | peer_ctl;
}
}
if (d->plr && d->plr->cbm > 0)
@@ -2361,9 +2532,14 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
* modify the CBM based on system availability.
*/
cbm_ensure_valid(&d->new_ctrl, r);
- if (bitmap_weight((unsigned long *) &d->new_ctrl,
- r->cache.cbm_len) <
- r->cache.min_cbm_bits) {
+ /*
+ * Assign the u32 CBM to an unsigned long to ensure
+ * that bitmap_weight() does not access out-of-bound
+ * memory.
+ */
+ tmp_cbm = d->new_ctrl;
+ if (bitmap_weight(&tmp_cbm, r->cache.cbm_len) <
+ r->cache.min_cbm_bits) {
rdt_last_cmd_printf("no space on %s:%d\n",
r->name, d->id);
return -ENOSPC;
@@ -2373,6 +2549,12 @@ static int rdtgroup_init_alloc(struct rdtgroup *rdtgrp)
}
for_each_alloc_enabled_rdt_resource(r) {
+ /*
+ * Only initialize default allocations for CBM cache
+ * resources
+ */
+ if (r->rid == RDT_RESOURCE_MBA)
+ continue;
ret = update_domains(r, rdtgrp->closid);
if (ret < 0) {
rdt_last_cmd_puts("failed to initialize allocations\n");
@@ -2760,6 +2942,13 @@ static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf)
{
if (rdt_resources_all[RDT_RESOURCE_L3DATA].alloc_enabled)
seq_puts(seq, ",cdp");
+
+ if (rdt_resources_all[RDT_RESOURCE_L2DATA].alloc_enabled)
+ seq_puts(seq, ",cdpl2");
+
+ if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA]))
+ seq_puts(seq, ",mba_MBps");
+
return 0;
}
generated by cgit (git 2.34.1) at 2024-06-17 23:52:12 +0000