eal: deduplicate timer functions
authorRavi Kerur <rkerur@gmail.com>
Sat, 25 Jul 2015 19:36:28 +0000 (12:36 -0700)
committerThomas Monjalon <thomas.monjalon@6wind.com>
Mon, 27 Jul 2015 00:11:00 +0000 (02:11 +0200)
Move common functions from BSD/Linux to eal_common_timer.c.
BSD uses sysctl and Linux uses CLOCK_MONOTIC_RAW to calibrate TSC.
HPET is specific to Linux and not integrated in the common init.

Signed-off-by: Ravi Kerur <rkerur@gmail.com>
Signed-off-by: Thomas Monjalon <thomas.monjalon@6wind.com>
lib/librte_eal/bsdapp/eal/Makefile
lib/librte_eal/bsdapp/eal/eal_timer.c
lib/librte_eal/common/eal_common_timer.c [new file with mode: 0644]
lib/librte_eal/common/eal_private.h
lib/librte_eal/linuxapp/eal/Makefile
lib/librte_eal/linuxapp/eal/eal_timer.c

index 24733ae..a969435 100644 (file)
@@ -61,6 +61,7 @@ SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_alarm.c
 
 # from common dir
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_lcore.c
+SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_timer.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_memzone.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_log.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_BSDAPP) += eal_common_launch.c
index 7147abe..f12d9bd 100644 (file)
 
 enum timer_source eal_timer_source = EAL_TIMER_TSC;
 
-/* The frequency of the RDTSC timer resolution */
-static uint64_t eal_tsc_resolution_hz = 0;
-
-void
-rte_delay_us(unsigned us)
-{
-       const uint64_t start = rte_get_timer_cycles();
-       const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
-       while ((rte_get_timer_cycles() - start) < ticks)
-               rte_pause();
-}
-
 uint64_t
-rte_get_tsc_hz(void)
-{
-       return eal_tsc_resolution_hz;
-}
-
-static int
-set_tsc_freq_from_sysctl(void)
+get_tsc_freq(void)
 {
        size_t sz;
        int tmp;
+       uint64_t tsc_hz;
 
        sz = sizeof(tmp);
        tmp = 0;
@@ -94,42 +77,13 @@ set_tsc_freq_from_sysctl(void)
        else if (tmp != 1)
                RTE_LOG(WARNING, EAL, "TSC is not invariant\n");
 
-       sz = sizeof(eal_tsc_resolution_hz);
-       if (sysctlbyname("machdep.tsc_freq", &eal_tsc_resolution_hz, &sz, NULL, 0)) {
+       sz = sizeof(tsc_hz);
+       if (sysctlbyname("machdep.tsc_freq", &tsc_hz, &sz, NULL, 0)) {
                RTE_LOG(WARNING, EAL, "%s\n", strerror(errno));
-               return -1;
+               return 0;
        }
 
-       return 0;
-}
-
-static void
-set_tsc_freq_fallback(void)
-{
-       RTE_LOG(WARNING, EAL, "WARNING: clock_gettime cannot use "
-                       "CLOCK_MONOTONIC_RAW and HPET is not available"
-                       " - clock timings may be less accurate.\n");
-       /* assume that the sleep(1) will sleep for 1 second */
-       uint64_t start = rte_rdtsc();
-       sleep(1);
-       eal_tsc_resolution_hz = rte_rdtsc() - start;
-}
-
-/*
- * This function measures the TSC frequency. It uses a variety of approaches.
- *
- * 1. Read the TSC frequency value provided by the kernel
- * 2. If above does not work, just sleep for 1 second and tune off that,
- *    printing a warning about inaccuracy of timing
- */
-static void
-set_tsc_freq(void)
-{
-       if (set_tsc_freq_from_sysctl() < 0)
-               set_tsc_freq_fallback();
-
-       RTE_LOG(INFO, EAL, "TSC frequency is ~%"PRIu64" KHz\n",
-                       eal_tsc_resolution_hz/1000);
+       return tsc_hz;
 }
 
 int
diff --git a/lib/librte_eal/common/eal_common_timer.c b/lib/librte_eal/common/eal_common_timer.c
new file mode 100644 (file)
index 0000000..2956703
--- /dev/null
@@ -0,0 +1,83 @@
+/*-
+ *   BSD LICENSE
+ *
+ *   Copyright(c) 2010-2014 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 <string.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <errno.h>
+
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_cycles.h>
+
+#include "eal_private.h"
+
+/* The frequency of the RDTSC timer resolution */
+static uint64_t eal_tsc_resolution_hz;
+
+void
+rte_delay_us(unsigned us)
+{
+       const uint64_t start = rte_get_timer_cycles();
+       const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
+       while ((rte_get_timer_cycles() - start) < ticks)
+               rte_pause();
+}
+
+uint64_t
+rte_get_tsc_hz(void)
+{
+       return eal_tsc_resolution_hz;
+}
+
+static uint64_t
+estimate_tsc_freq(void)
+{
+       RTE_LOG(WARNING, EAL, "WARNING: TSC frequency estimated roughly"
+               " - clock timings may be less accurate.\n");
+       /* assume that the sleep(1) will sleep for 1 second */
+       uint64_t start = rte_rdtsc();
+       sleep(1);
+       return rte_rdtsc() - start;
+}
+
+void
+set_tsc_freq(void)
+{
+       uint64_t freq = get_tsc_freq() || estimate_tsc_freq();
+       RTE_LOG(INFO, EAL, "TSC frequency is ~%" PRIu64 " KHz\n", freq / 1000);
+       eal_tsc_resolution_hz = freq;
+}
index 8505b05..f8e8869 100644 (file)
@@ -314,4 +314,18 @@ unsigned eal_cpu_core_id(unsigned lcore_id);
  */
 int eal_cpu_detected(unsigned lcore_id);
 
+/**
+ * Set TSC frequency from precise value or estimation
+ *
+ * This function is private to the EAL.
+ */
+void set_tsc_freq(void);
+
+/**
+ * Get precise TSC frequency from system
+ *
+ * This function is private to the EAL.
+ */
+uint64_t get_tsc_freq(void);
+
 #endif /* _EAL_PRIVATE_H_ */
index f4f8cdf..376d275 100644 (file)
@@ -71,6 +71,7 @@ endif
 
 # from common dir
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_lcore.c
+SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_timer.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_memzone.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_log.c
 SRCS-$(CONFIG_RTE_LIBRTE_EAL_LINUXAPP) += eal_common_launch.c
index 94909ed..76a8a65 100644 (file)
@@ -57,9 +57,6 @@
 
 enum timer_source eal_timer_source = EAL_TIMER_HPET;
 
-/* The frequency of the RDTSC timer resolution */
-static uint64_t eal_tsc_resolution_hz = 0;
-
 #ifdef RTE_LIBEAL_USE_HPET
 
 #define DEV_HPET "/dev/hpet"
@@ -160,23 +157,6 @@ rte_get_hpet_cycles(void)
 
 #endif
 
-
-void
-rte_delay_us(unsigned us)
-{
-       const uint64_t start = rte_get_timer_cycles();
-       const uint64_t ticks = (uint64_t)us * rte_get_timer_hz() / 1E6;
-       while ((rte_get_timer_cycles() - start) < ticks)
-               rte_pause();
-}
-
-uint64_t
-rte_get_tsc_hz(void)
-{
-       return eal_tsc_resolution_hz;
-}
-
-
 #ifdef RTE_LIBEAL_USE_HPET
 /*
  * Open and mmap /dev/hpet (high precision event timer) that will
@@ -275,8 +255,8 @@ check_tsc_flags(void)
        fclose(stream);
 }
 
-static int
-set_tsc_freq_from_clock(void)
+uint64_t
+get_tsc_freq(void)
 {
 #ifdef CLOCK_MONOTONIC_RAW
 #define NS_PER_SEC 1E9
@@ -284,6 +264,7 @@ set_tsc_freq_from_clock(void)
        struct timespec sleeptime = {.tv_nsec = 5E8 }; /* 1/2 second */
 
        struct timespec t_start, t_end;
+       uint64_t tsc_hz;
 
        if (clock_gettime(CLOCK_MONOTONIC_RAW, &t_start) == 0) {
                uint64_t ns, end, start = rte_rdtsc();
@@ -294,40 +275,11 @@ set_tsc_freq_from_clock(void)
                ns += (t_end.tv_nsec - t_start.tv_nsec);
 
                double secs = (double)ns/NS_PER_SEC;
-               eal_tsc_resolution_hz = (uint64_t)((end - start)/secs);
-               return 0;
+               tsc_hz = (uint64_t)((end - start)/secs);
+               return tsc_hz;
        }
 #endif
-       return -1;
-}
-
-static void
-set_tsc_freq_fallback(void)
-{
-       RTE_LOG(WARNING, EAL, "WARNING: clock_gettime cannot use "
-                       "CLOCK_MONOTONIC_RAW and HPET is not available"
-                       " - clock timings may be less accurate.\n");
-       /* assume that the sleep(1) will sleep for 1 second */
-       uint64_t start = rte_rdtsc();
-       sleep(1);
-       eal_tsc_resolution_hz = rte_rdtsc() - start;
-}
-/*
- * This function measures the TSC frequency. It uses a variety of approaches.
- *
- * 1. If kernel provides CLOCK_MONOTONIC_RAW we use that to tune the TSC value
- * 2. If kernel does not provide that, and we have HPET support, tune using HPET
- * 3. Lastly, if neither of the above can be used, just sleep for 1 second and
- * tune off that, printing a warning about inaccuracy of timing
- */
-static void
-set_tsc_freq(void)
-{
-       if (set_tsc_freq_from_clock() < 0)
-               set_tsc_freq_fallback();
-
-       RTE_LOG(INFO, EAL, "TSC frequency is ~%"PRIu64" KHz\n",
-                       eal_tsc_resolution_hz/1000);
+       return 0;
 }
 
 int