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From: Reinette Chatre <reinette.chatre@intel.com>
To: tglx@linutronix.de, fenghua.yu@intel.com, tony.luck@intel.com,
	vikas.shivappa@linux.intel.com
Cc: gavin.hindman@intel.com, jithu.joseph@intel.com,
	dave.hansen@intel.com, mingo@redhat.com, hpa@zytor.com,
	x86@kernel.org, linux-kernel@vger.kernel.org,
	Reinette Chatre <reinette.chatre@intel.com>
Subject: [PATCH V4 13/38] x86/intel_rdt: Introduce "bit_usage" to display cache allocations details
Date: Tue, 22 May 2018 04:29:01 -0700	[thread overview]
Message-ID: <ce0208727776e5a523657ce5607325fc6c33cf98.1526987654.git.reinette.chatre@intel.com> (raw)
In-Reply-To: <cover.1526987654.git.reinette.chatre@intel.com>
In-Reply-To: <cover.1526987654.git.reinette.chatre@intel.com>

With cache regions now explicitly marked as "shareable" or "exclusive"
we would like to communicate to the user how portions of the cache
are used.

Introduce "bit_usage" that indicates for each resource
how portions of the cache are configured to be used.

To assist the user to distinguish whether the sharing is from software or
hardware we add the following annotation:

0 - currently unused
X - currently available for sharing and used by software and hardware
H - currently used by hardware only but available for software use
S - currently used and shareable by software only
E - currently used exclusively by one resource group

Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
---
 arch/x86/kernel/cpu/intel_rdt_rdtgroup.c | 79 ++++++++++++++++++++++++++++++++
 1 file changed, 79 insertions(+)

diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index 5b78b4aa1a50..d0040f83532d 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -714,6 +714,78 @@ static int rdt_shareable_bits_show(struct kernfs_open_file *of,
 	return 0;
 }
 
+/**
+ * rdt_bit_usage_show - Display current usage of resources
+ *
+ * A domain is a shared resource that can now be allocated differently. Here
+ * we display the current regions of the domain as an annotated bitmask.
+ * For each domain of this resource its allocation bitmask
+ * is annotated as below to indicate the current usage of the corresponding bit:
+ *   0 - currently unused
+ *   X - currently available for sharing and used by software and hardware
+ *   H - currently used by hardware only but available for software use
+ *   S - currently used and shareable by software only
+ *   E - currently used exclusively by one resource group
+ */
+static int rdt_bit_usage_show(struct kernfs_open_file *of,
+			      struct seq_file *seq, void *v)
+{
+	struct rdt_resource *r = of->kn->parent->priv;
+	u32 sw_shareable, hw_shareable, exclusive;
+	struct rdt_domain *dom;
+	int i, hwb, swb, excl;
+	enum rdtgrp_mode mode;
+	bool sep = false;
+	u32 *ctrl;
+
+	mutex_lock(&rdtgroup_mutex);
+	hw_shareable = r->cache.shareable_bits;
+	list_for_each_entry(dom, &r->domains, list) {
+		if (sep)
+			seq_puts(seq, ";");
+		ctrl = dom->ctrl_val;
+		sw_shareable = 0;
+		exclusive = 0;
+		seq_printf(seq, "%d=", dom->id);
+		for (i = 0; i < r->num_closid; i++, ctrl++) {
+			if (!closid_allocated(i))
+				continue;
+			mode = rdtgroup_mode_by_closid(i);
+			switch (mode) {
+			case RDT_MODE_SHAREABLE:
+				sw_shareable |= *ctrl;
+				break;
+			case RDT_MODE_EXCLUSIVE:
+				exclusive |= *ctrl;
+				break;
+			case RDT_NUM_MODES:
+				WARN(1,
+				     "invalid mode for closid %d\n", i);
+				break;
+			}
+		}
+		for (i = r->cache.cbm_len - 1; i >= 0; i--) {
+			hwb = test_bit(i, (unsigned long *)&hw_shareable);
+			swb = test_bit(i, (unsigned long *)&sw_shareable);
+			excl = test_bit(i, (unsigned long *)&exclusive);
+			if (hwb && swb)
+				seq_puts(seq, "X");
+			else if (hwb && !swb)
+				seq_puts(seq, "H");
+			else if (!hwb && swb)
+				seq_puts(seq, "S");
+			else if (excl)
+				seq_puts(seq, "E");
+			else /* Unused bits remain */
+				seq_puts(seq, "0");
+		}
+		sep = true;
+	}
+	seq_puts(seq, "\n");
+	mutex_unlock(&rdtgroup_mutex);
+	return 0;
+}
+
 static int rdt_min_bw_show(struct kernfs_open_file *of,
 			     struct seq_file *seq, void *v)
 {
@@ -996,6 +1068,13 @@ static struct rftype res_common_files[] = {
 		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
 	},
 	{
+		.name		= "bit_usage",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= rdt_bit_usage_show,
+		.fflags		= RF_CTRL_INFO | RFTYPE_RES_CACHE,
+	},
+	{
 		.name		= "min_bandwidth",
 		.mode		= 0444,
 		.kf_ops		= &rdtgroup_kf_single_ops,
-- 
2.13.6

  parent reply	other threads:[~2018-05-22 19:37 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-22 11:28 [PATCH V4 00/38] Intel(R) Resource Director Technology Cache Pseudo-Locking enabling Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 01/38] x86/intel_rdt: Document new mode, size, and bit_usage Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 02/38] x86/intel_rdt: Introduce RDT resource group mode Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 03/38] x86/intel_rdt: Associate mode with each RDT resource group Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 04/38] x86/intel_rdt: Introduce resource group's mode resctrl file Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 05/38] x86/intel_rdt: Introduce test to determine if closid is in use Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 06/38] x86/intel_rdt: Make useful functions available internally Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 07/38] x86/intel_rdt: Initialize new resource group with sane defaults Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 08/38] x86/intel_rdt: Introduce new "exclusive" mode Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 09/38] x86/intel_rdt: Enable setting of exclusive mode Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 10/38] x86/intel_rdt: Making CBM name and type more explicit Reinette Chatre
2018-05-22 11:28 ` [PATCH V4 11/38] x86/intel_rdt: Support flexible data to parsing callbacks Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 12/38] x86/intel_rdt: Ensure requested schemata respects mode Reinette Chatre
2018-05-22 11:29 ` Reinette Chatre [this message]
2018-05-22 21:03   ` [PATCH V4 13/38] x86/intel_rdt: Introduce "bit_usage" to display cache allocations details Randy Dunlap
2018-05-22 21:09     ` Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 14/38] x86/intel_rdt: Display resource groups' allocations' size in bytes Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 15/38] x86/intel_rdt: Documentation for Cache Pseudo-Locking Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 16/38] x86/intel_rdt: Introduce the Cache Pseudo-Locking modes Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 17/38] x86/intel_rdt: Respect read and write access Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 18/38] x86/intel_rdt: Add utility to test if tasks assigned to resource group Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 19/38] x86/intel_rdt: Add utility to restrict/restore access to resctrl files Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 20/38] x86/intel_rdt: Protect against resource group changes during locking Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 21/38] x86/intel_rdt: Utilities to restrict/restore access to specific files Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 22/38] x86/intel_rdt: Add check to determine if monitoring in progress Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 23/38] x86/intel_rdt: Introduce pseudo-locked region Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 24/38] x86/intel_rdt: Support enter/exit of locksetup mode Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 25/38] x86/intel_rdt: Enable entering of pseudo-locksetup mode Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 26/38] x86/intel_rdt: Split resource group removal in two Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 27/38] x86/intel_rdt: Add utilities to test pseudo-locked region possibility Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 28/38] x86/intel_rdt: Discover supported platforms via prefetch disable bits Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 29/38] x86/intel_rdt: Pseudo-lock region creation/removal core Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 30/38] x86/intel_rdt: Support creation/removal of pseudo-locked region Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 31/38] x86/intel_rdt: resctrl files reflect pseudo-locked information Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 32/38] x86/intel_rdt: Ensure RDT cleanup on exit Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 33/38] x86/intel_rdt: Create resctrl debug area Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 34/38] x86/intel_rdt: Create debugfs files for pseudo-locking testing Reinette Chatre
2018-05-22 19:43   ` Greg KH
2018-05-22 21:02     ` Reinette Chatre
2018-05-23  8:05       ` Greg KH
2018-05-23 17:19         ` Reinette Chatre
2018-05-23 17:27           ` Greg KH
2018-05-22 11:29 ` [PATCH V4 35/38] x86/intel_rdt: Create character device exposing pseudo-locked region Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 36/38] x86/intel_rdt: More precise L2 hit/miss measurements Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 37/38] x86/intel_rdt: Support L3 cache performance event of Broadwell Reinette Chatre
2018-05-22 11:29 ` [PATCH V4 38/38] x86/intel_rdt: Limit C-states dynamically when pseudo-locking active Reinette Chatre

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