[PATCH] eal/x86: implement x86 specific tsc hz

* [PATCH] eal/x86: implement x86 specific tsc hz
@ 2017-08-23 15:00 Sergio Gonzalez Monroy
  2017-08-23 15:00 ` [PATCH] eal/x86: use cpuid builtin Sergio Gonzalez Monroy
                   ` (2 more replies)
  0 siblings, 3 replies; 11+ messages in thread
From: Sergio Gonzalez Monroy @ 2017-08-23 15:00 UTC (permalink / raw)
  To: dev; +Cc: konstantin.ananyev, bruce.richardson

First, try to use CPUID Time Stamp Counter and Nominal Core Crystal
Clock Information Leaf to determine the tsc hz on platforms that
supports it (does not require priviledge user).

If the CPUID leaf is not available, then try to determine the tsc hz by
reading the MSR 0xCE (requires priviledge user).

Default to the tsc hz estimation if both methods fail.

Signed-off-by: Sergio Gonzalez Monroy <sergio.gonzalez.monroy@intel.com>
---

DEPENDS on Jerin's patch:
http://dpdk.org/dev/patchwork/patch/27526/

 lib/librte_eal/common/arch/x86/rte_cycles.c        | 142 +++++++++++++++++++++
 .../common/include/arch/x86/rte_cycles.h           |   7 +-
 lib/librte_eal/linuxapp/eal/Makefile               |   1 +
 3 files changed, 145 insertions(+), 5 deletions(-)
 create mode 100644 lib/librte_eal/common/arch/x86/rte_cycles.c

diff --git a/lib/librte_eal/common/arch/x86/rte_cycles.c b/lib/librte_eal/common/arch/x86/rte_cycles.c
new file mode 100644
index 0000000..9336947
--- /dev/null
+++ b/lib/librte_eal/common/arch/x86/rte_cycles.c
@@ -0,0 +1,142 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2017 Intel Corporation. All rights reserved.
+ *   All rights reserved.
+ *
+ *   Redistribution and use in source and binary forms, with or without
+ *   modification, are permitted provided that the following conditions
+ *   are met:
+ *
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * Redistributions in binary form must reproduce the above copyright
+ *       notice, this list of conditions and the following disclaimer in
+ *       the documentation and/or other materials provided with the
+ *       distribution.
+ *     * Neither the name of Intel Corporation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <fcntl.h>
+#include <unistd.h>
+#include <cpuid.h>
+#include <rte_cycles.h>
+
+static unsigned int
+rte_cpu_get_model(uint32_t fam_mod_step)
+{
+	uint32_t family, model, ext_model;
+
+	family = (fam_mod_step >> 8) & 0xf;
+	model = (fam_mod_step >> 4) & 0xf;
+
+	if (family == 6 || family == 15) {
+		ext_model = (fam_mod_step >> 16) & 0xf;
+		model += (ext_model << 4);
+	}
+
+	return model;
+}
+
+static int32_t
+rdmsr(int msr, uint64_t *val)
+{
+	int fd;
+	int ret = 0;
+
+	fd = open("/dev/cpu/0/msr", O_RDONLY);
+	if (fd < 0)
+		return fd;
+
+	ret = pread(fd, val, sizeof(uint64_t), msr);
+
+	close(fd);
+
+	return ret;
+}
+
+static uint32_t
+check_model_wsm_nhm(uint8_t model)
+{
+	switch (model) {
+	/* Westmere */
+	case 0x25:
+	case 0x2C:
+	case 0x2F:
+	/* Nehalem */
+	case 0x1E:
+	case 0x1F:
+	case 0x1A:
+	case 0x2E:
+		return 1;
+	}
+
+	return 0;
+}
+
+static uint32_t
+check_model_gdm_dnv(uint8_t model)
+{
+	switch (model) {
+	/* Goldmont */
+	case 0x5C:
+	/* Denverton */
+	case 0x5F:
+		return 1;
+	}
+
+	return 0;
+}
+
+uint64_t
+rte_rdtsc_arch_hz(void)
+{
+	uint64_t tsc_hz = 0;
+	uint32_t a, b, c, d, maxleaf;
+	uint8_t mult, model;
+	int32_t ret;
+
+	/*
+	 * Time Stamp Counter and Nominal Core Crystal Clock
+	 * Information Leaf
+	 */
+	maxleaf = __get_cpuid_max(0, NULL);
+
+	if (maxleaf >= 0x15) {
+		__cpuid(0x15, a, b, c, d);
+
+		/* EBX : TSC/Crystal ratio, ECX : Crystal Hz */
+		if (b && c)
+			return c * (b / a);
+	}
+
+	__cpuid(0x1, a, b, c, d);
+	model = rte_cpu_get_model(a);
+
+	if (check_model_wsm_nhm(model))
+		mult = 133;
+	else if ((c & bit_AVX) || check_model_gdm_dnv(model))
+		mult = 100;
+	else
+		return 0;
+
+	ret = rdmsr(0xCE, &tsc_hz);
+	if (!(ret < 0))
+		return ((tsc_hz >> 8) & 0xff) * mult * 1E6;
+
+	return 0;
+}
diff --git a/lib/librte_eal/common/include/arch/x86/rte_cycles.h b/lib/librte_eal/common/include/arch/x86/rte_cycles.h
index e2661e2..0db89dc 100644
--- a/lib/librte_eal/common/include/arch/x86/rte_cycles.h
+++ b/lib/librte_eal/common/include/arch/x86/rte_cycles.h
@@ -84,11 +84,8 @@ rte_rdtsc(void)
  *   The number of rdtsc cycles in one second. Return zero if the architecture
  *   support is not available.
  */
-static inline uint64_t
-rte_rdtsc_arch_hz(void)
-{
-	return 0;
-}
+uint64_t
+rte_rdtsc_arch_hz(void);
 
 static inline uint64_t
 rte_rdtsc_precise(void)
diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index 90bca4d..9d44828 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -104,6 +104,7 @@ SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_service.c
 # from arch dir
 SRCS-$(CONFIG_RTE_EXEC_ENV_LINUXAPP) += rte_cpuflags.c
 SRCS-$(CONFIG_RTE_ARCH_X86) += rte_spinlock.c
+SRCS-$(CONFIG_RTE_ARCH_X86) += rte_cycles.c
 
 CFLAGS_eal_common_cpuflags.o := $(CPUFLAGS_LIST)
 
-- 
2.9.5

^ permalink raw reply related	[flat|nested] 11+ messages in thread