1 files changed, 99 insertions, 14 deletions

diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
index b2d178d3556e..cc4237c57cbe 100644
--- a/fs/resctrl/ctrlmondata.c
+++ b/fs/resctrl/ctrlmondata.c
@@ -17,6 +17,7 @@
 
 #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>
@@ -551,8 +552,8 @@ struct rdt_domain_hdr *resctrl_find_domain(struct list_head *h, int id,
 }
 
 void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
-		    struct rdt_mon_domain *d, struct rdtgroup *rdtgrp,
-		    cpumask_t *cpumask, int evtid, int first)
+		    struct rdt_domain_hdr *hdr, struct rdtgroup *rdtgrp,
+		    cpumask_t *cpumask, struct mon_evt *evt, int first)
 {
 	int cpu;
 
@@ -563,21 +564,26 @@ void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 	 * Setup the parameters to pass to mon_event_count() to read the data.
 	 */
 	rr->rgrp = rdtgrp;
-	rr->evtid = evtid;
+	rr->evt = evt;
 	rr->r = r;
-	rr->d = d;
+	rr->hdr = hdr;
 	rr->first = first;
 	if (resctrl_arch_mbm_cntr_assign_enabled(r) &&
-	    resctrl_is_mbm_event(evtid)) {
+	    resctrl_is_mbm_event(evt->evtid)) {
 		rr->is_mbm_cntr = true;
 	} else {
-		rr->arch_mon_ctx = resctrl_arch_mon_ctx_alloc(r, evtid);
+		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);
 
 	/*
@@ -591,22 +597,93 @@ void mon_event_read(struct rmid_read *rr, struct rdt_resource *r,
 	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, evtid, 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;
-	enum resctrl_event_id evtid;
 	struct rdt_domain_hdr *hdr;
 	struct rmid_read rr = {0};
-	struct rdt_mon_domain *d;
 	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);
@@ -623,10 +700,17 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 
 	resid = md->rid;
 	domid = md->domid;
-	evtid = md->evtid;
+	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
@@ -641,7 +725,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 					continue;
 				rr.ci = ci;
 				mon_event_read(&rr, r, NULL, rdtgrp,
-					       &ci->shared_cpu_map, evtid, false);
+					       &ci->shared_cpu_map, evt, false);
 				goto checkresult;
 			}
 		}
@@ -653,12 +737,11 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg)
 		 * the resource to find the domain with "domid".
 		 */
 		hdr = resctrl_find_domain(&r->mon_domains, domid, NULL);
-		if (!hdr || WARN_ON_ONCE(hdr->type != RESCTRL_MON_DOMAIN)) {
+		if (!hdr) {
 			ret = -ENOENT;
 			goto out;
 		}
-		d = container_of(hdr, struct rdt_mon_domain, hdr);
-		mon_event_read(&rr, r, d, rdtgrp, &d->hdr.cpu_mask, evtid, false);
+		mon_event_read(&rr, r, hdr, rdtgrp, &hdr->cpu_mask, evt, false);
 	}
 
 checkresult:
@@ -673,6 +756,8 @@ checkresult:
 		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);