linux-kernel - [PATCH 4.9 147/152] tools/power turbostat: decode Baytrail CC6 and MC6 demotion configuration

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 10 Apr 2017 18:43:19 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Len Brown <len.brown@...el.com>,
        Sasha Levin <alexander.levin@...izon.com>
Subject: [PATCH 4.9 147/152] tools/power turbostat: decode Baytrail CC6 and MC6 demotion configuration

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Len Brown <len.brown@...el.com>

[ Upstream commit 71616c8e936a6dd541f0627d7bf4ff09971d8ccb ]

with --debug, see:

cpu0: MSR_CC6_DEMOTION_POLICY_CONFIG: 0x00000000 (DISable-CC6-Demotion)
cpu0: MSR_MC6_DEMOTION_POLICY_CONFIG: 0x00000000 (DISable-MC6-Demotion)

Note that the hardware default is to enable demotion,
and Linux started clearing these registers in 3.17.

Signed-off-by: Len Brown <len.brown@...el.com>
Signed-off-by: Sasha Levin <alexander.levin@...izon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
---
 tools/power/x86/turbostat/turbostat.c |   42 ++++++++++++++++++++++++++++++++++
 1 file changed, 42 insertions(+)

--- a/tools/power/x86/turbostat/turbostat.c
+++ b/tools/power/x86/turbostat/turbostat.c
@@ -2951,6 +2951,27 @@ int has_snb_msrs(unsigned int family, un
 }
 
 /*
+ * SLV client has supporet for unique MSRs:
+ *
+ * MSR_CC6_DEMOTION_POLICY_CONFIG
+ * MSR_MC6_DEMOTION_POLICY_CONFIG
+ */
+
+int has_slv_msrs(unsigned int family, unsigned int model)
+{
+	if (!genuine_intel)
+		return 0;
+
+	switch (model) {
+	case INTEL_FAM6_ATOM_SILVERMONT1:
+	case INTEL_FAM6_ATOM_MERRIFIELD:
+	case INTEL_FAM6_ATOM_MOOREFIELD:
+		return 1;
+	}
+	return 0;
+}
+
+/*
  * HSW adds support for additional MSRs:
  *
  * MSR_PKG_C8_RESIDENCY		0x00000630
@@ -3179,6 +3200,24 @@ void decode_misc_pwr_mgmt_msr(void)
 			msr & (1 << 0) ? "DIS" : "EN",
 			msr & (1 << 1) ? "EN" : "DIS");
 }
+/*
+ * Decode MSR_CC6_DEMOTION_POLICY_CONFIG, MSR_MC6_DEMOTION_POLICY_CONFIG
+ *
+ * This MSRs are present on Silvermont processors,
+ * Intel Atom processor E3000 series (Baytrail), and friends.
+ */
+void decode_c6_demotion_policy_msr(void)
+{
+	unsigned long long msr;
+
+	if (!get_msr(base_cpu, MSR_CC6_DEMOTION_POLICY_CONFIG, &msr))
+		fprintf(outf, "cpu%d: MSR_CC6_DEMOTION_POLICY_CONFIG: 0x%08llx (%sable-CC6-Demotion)\n",
+			base_cpu, msr, msr & (1 << 0) ? "EN" : "DIS");
+
+	if (!get_msr(base_cpu, MSR_MC6_DEMOTION_POLICY_CONFIG, &msr))
+		fprintf(outf, "cpu%d: MSR_MC6_DEMOTION_POLICY_CONFIG: 0x%08llx (%sable-MC6-Demotion)\n",
+			base_cpu, msr, msr & (1 << 0) ? "EN" : "DIS");
+}
 
 void process_cpuid()
 {
@@ -3360,6 +3399,9 @@ void process_cpuid()
 	if (debug)
 		decode_misc_pwr_mgmt_msr();
 
+	if (debug && has_slv_msrs(family, model))
+		decode_c6_demotion_policy_msr();
+
 	rapl_probe(family, model);
 	perf_limit_reasons_probe(family, model);