From: Thomas Monjalon <thomas.monjalon@6wind.com>
To: david.marchand@6wind.com
Cc: dev@dpdk.org
Subject: [dpdk-dev] [PATCH v10 2/3] eal: deduplicate timer functions
Date: Mon, 27 Jul 2015 02:56:33 +0200 [thread overview]
Message-ID: <1437958594-29468-3-git-send-email-thomas.monjalon@6wind.com> (raw)
In-Reply-To: <1437958594-29468-1-git-send-email-thomas.monjalon@6wind.com>
From: Ravi Kerur <rkerur@gmail.com>
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 | 1 +
lib/librte_eal/bsdapp/eal/eal_timer.c | 58 ++--------------
.../eal/eal_timer.c => common/eal_common_timer.c} | 79 +++-------------------
lib/librte_eal/common/eal_private.h | 14 ++++
lib/librte_eal/linuxapp/eal/Makefile | 1 +
lib/librte_eal/linuxapp/eal/eal_timer.c | 60 ++--------------
6 files changed, 39 insertions(+), 174 deletions(-)
copy lib/librte_eal/{bsdapp/eal/eal_timer.c => common/eal_common_timer.c} (57%)
diff --git a/lib/librte_eal/bsdapp/eal/Makefile b/lib/librte_eal/bsdapp/eal/Makefile
index 24733ae..a969435 100644
--- a/lib/librte_eal/bsdapp/eal/Makefile
+++ b/lib/librte_eal/bsdapp/eal/Makefile
@@ -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
diff --git a/lib/librte_eal/bsdapp/eal/eal_timer.c b/lib/librte_eal/bsdapp/eal/eal_timer.c
index 7147abe..f12d9bd 100644
--- a/lib/librte_eal/bsdapp/eal/eal_timer.c
+++ b/lib/librte_eal/bsdapp/eal/eal_timer.c
@@ -55,29 +55,12 @@
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/bsdapp/eal/eal_timer.c b/lib/librte_eal/common/eal_common_timer.c
similarity index 57%
copy from lib/librte_eal/bsdapp/eal/eal_timer.c
copy to lib/librte_eal/common/eal_common_timer.c
index 7147abe..2956703 100644
--- a/lib/librte_eal/bsdapp/eal/eal_timer.c
+++ b/lib/librte_eal/common/eal_common_timer.c
@@ -30,6 +30,7 @@
* (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>
@@ -41,22 +42,11 @@
#include <rte_common.h>
#include <rte_log.h>
#include <rte_cycles.h>
-#include <rte_memory.h>
-#include <rte_memzone.h>
-#include <rte_eal.h>
-#include <rte_debug.h>
#include "eal_private.h"
-#include "eal_internal_cfg.h"
-
-#ifdef RTE_LIBEAL_USE_HPET
-#warning HPET is not supported in FreeBSD
-#endif
-
-enum timer_source eal_timer_source = EAL_TIMER_TSC;
/* The frequency of the RDTSC timer resolution */
-static uint64_t eal_tsc_resolution_hz = 0;
+static uint64_t eal_tsc_resolution_hz;
void
rte_delay_us(unsigned us)
@@ -73,68 +63,21 @@ rte_get_tsc_hz(void)
return eal_tsc_resolution_hz;
}
-static int
-set_tsc_freq_from_sysctl(void)
+static uint64_t
+estimate_tsc_freq(void)
{
- size_t sz;
- int tmp;
-
- sz = sizeof(tmp);
- tmp = 0;
-
- if (sysctlbyname("kern.timecounter.smp_tsc", &tmp, &sz, NULL, 0))
- RTE_LOG(WARNING, EAL, "%s\n", strerror(errno));
- else if (tmp != 1)
- RTE_LOG(WARNING, EAL, "TSC is not safe to use in SMP mode\n");
-
- tmp = 0;
-
- if (sysctlbyname("kern.timecounter.invariant_tsc", &tmp, &sz, NULL, 0))
- RTE_LOG(WARNING, EAL, "%s\n", strerror(errno));
- 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)) {
- RTE_LOG(WARNING, EAL, "%s\n", strerror(errno));
- return -1;
- }
-
- 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");
+ 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);
- eal_tsc_resolution_hz = rte_rdtsc() - start;
+ return 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
+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);
-}
-
-int
-rte_eal_timer_init(void)
-{
- set_tsc_freq();
- return 0;
+ 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;
}
diff --git a/lib/librte_eal/common/eal_private.h b/lib/librte_eal/common/eal_private.h
index 8505b05..f8e8869 100644
--- a/lib/librte_eal/common/eal_private.h
+++ b/lib/librte_eal/common/eal_private.h
@@ -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_ */
diff --git a/lib/librte_eal/linuxapp/eal/Makefile b/lib/librte_eal/linuxapp/eal/Makefile
index f4f8cdf..376d275 100644
--- a/lib/librte_eal/linuxapp/eal/Makefile
+++ b/lib/librte_eal/linuxapp/eal/Makefile
@@ -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
diff --git a/lib/librte_eal/linuxapp/eal/eal_timer.c b/lib/librte_eal/linuxapp/eal/eal_timer.c
index 94909ed..76a8a65 100644
--- a/lib/librte_eal/linuxapp/eal/eal_timer.c
+++ b/lib/librte_eal/linuxapp/eal/eal_timer.c
@@ -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
--
2.4.2
next prev parent reply other threads:[~2015-07-27 0:57 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-07-25 19:34 [dpdk-dev] [PATCH v9 0/3] Move EAL common functions Ravi Kerur
2015-07-25 19:36 ` [dpdk-dev] [PATCH v9 1/3] Move common functions in eal_lcore.c Ravi Kerur
2015-07-25 19:36 ` [dpdk-dev] [PATCH v9 2/3] Move common functions in eal_timer.c Ravi Kerur
2015-07-26 23:32 ` Thomas Monjalon
2015-07-26 23:40 ` Thomas Monjalon
2015-07-25 19:36 ` [dpdk-dev] [PATCH v9 3/3] Move common functions in eal_memory.c Ravi Kerur
2015-07-27 0:35 ` Thomas Monjalon
2015-07-25 19:36 ` [dpdk-dev] [PATCH v9 0/3] Move EAL common functions Ravi Kerur
2015-07-27 0:56 ` [dpdk-dev] [PATCH v10 0/3] deduplicate " Thomas Monjalon
2015-07-27 0:56 ` [dpdk-dev] [PATCH v10 1/3] eal: deduplicate lcore initialization Thomas Monjalon
2015-07-27 0:56 ` Thomas Monjalon [this message]
2015-07-27 0:56 ` [dpdk-dev] [PATCH v10 3/3] eal: deduplicate memory initialization Thomas Monjalon
2015-07-27 0:59 ` [dpdk-dev] [PATCH v10 0/3] deduplicate EAL common functions Thomas Monjalon
2015-07-30 8:12 ` Olivier MATZ
2015-07-30 12:15 ` Ravi Kerur
2015-07-30 13:43 ` Thomas Monjalon
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