[dpdk-dev] [PATCH v4 0/2] eal timer split and implementation for Windows

[dpdk-dev] [PATCH v4 0/2] eal timer split and implementation for Windows

[Fady Bader]

This patchset splits OS dependent EAL timer functions and implements them for windows.

v2:
    * fixing styles and correctness errors.
v3:
    * fixing correctness, get_tsc_freq was reimplemented.
v4:
    * rebasing to the new version of "Windows basic memory management" series
    * fixing styles and correctness errors.

Depends-on: series-9374 ("Windows basic memory management")
	
Fady Bader (2):
  timer: move from common to Unix directory
  timer: support EAL functions on Windows

 lib/librte_eal/common/eal_common_timer.c | 22 --------
 lib/librte_eal/common/meson.build        |  1 +
 lib/librte_eal/unix/eal_timer.c          | 29 ++++++++++
 lib/librte_eal/unix/meson.build          |  1 +
 lib/librte_eal/windows/eal.c             |  6 ++
 lib/librte_eal/windows/eal_timer.c       | 96 ++++++++++++++++++++++++++++++++
 lib/librte_eal/windows/include/rte_os.h  |  2 +
 lib/librte_eal/windows/meson.build       |  1 +
 8 files changed, 136 insertions(+), 22 deletions(-)
 create mode 100644 lib/librte_eal/unix/eal_timer.c
 create mode 100644 lib/librte_eal/windows/eal_timer.c

-- 
2.16.1.windows.4

[dpdk-dev] [PATCH v4 1/2] timer: move from common to Unix directory

[Fady Bader]

Eal common timer doesn't compile under Windows.

Compilation log:
error LNK2019:
unresolved external symbol nanosleep referenced in function
rte_delay_us_sleep
error LNK2019:
unresolved external symbol get_tsc_freq referenced in function set_tsc_freq
error LNK2019:
unresolved external symbol sleep referenced in function set_tsc_freq

The reason was that some functions called POSIX functions.
The solution was to move POSIX dependent functions from common to Unix.

Signed-off-by: Fady Bader <fady@mellanox.com>
---
 lib/librte_eal/common/eal_common_timer.c | 22 ----------------------
 lib/librte_eal/unix/eal_timer.c          | 29 +++++++++++++++++++++++++++++
 lib/librte_eal/unix/meson.build          |  1 +
 3 files changed, 30 insertions(+), 22 deletions(-)
 create mode 100644 lib/librte_eal/unix/eal_timer.c

diff --git a/lib/librte_eal/common/eal_common_timer.c b/lib/librte_eal/common/eal_common_timer.c
index fa9ee1b22..71e0bd035 100644
--- a/lib/librte_eal/common/eal_common_timer.c
+++ b/lib/librte_eal/common/eal_common_timer.c
@@ -35,28 +35,6 @@ rte_delay_us_block(unsigned int us)
 		rte_pause();
 }
 
-void
-rte_delay_us_sleep(unsigned int us)
-{
-	struct timespec wait[2];
-	int ind = 0;
-
-	wait[0].tv_sec = 0;
-	if (us >= US_PER_S) {
-		wait[0].tv_sec = us / US_PER_S;
-		us -= wait[0].tv_sec * US_PER_S;
-	}
-	wait[0].tv_nsec = 1000 * us;
-
-	while (nanosleep(&wait[ind], &wait[1 - ind]) && errno == EINTR) {
-		/*
-		 * Sleep was interrupted. Flip the index, so the 'remainder'
-		 * will become the 'request' for a next call.
-		 */
-		ind = 1 - ind;
-	}
-}
-
 uint64_t
 rte_get_tsc_hz(void)
 {
diff --git a/lib/librte_eal/unix/eal_timer.c b/lib/librte_eal/unix/eal_timer.c
new file mode 100644
index 000000000..dc3a7925f
--- /dev/null
+++ b/lib/librte_eal/unix/eal_timer.c
@@ -0,0 +1,29 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2020 Mellanox Technologies, Ltd
+ */
+#include <time.h>
+
+#include <rte_cycles.h>
+
+void
+rte_delay_us_sleep(unsigned int us)
+{
+	struct timespec wait[2];
+	int ind = 0;
+
+	wait[0].tv_sec = 0;
+	if (us >= US_PER_S) {
+		wait[0].tv_sec = us / US_PER_S;
+		us -= wait[0].tv_sec * US_PER_S;
+	}
+	wait[0].tv_nsec = 1000 * us;
+
+	while (nanosleep(&wait[ind], &wait[1 - ind]) && errno == EINTR) {
+		/*
+		 * Sleep was interrupted. Flip the index, so the 'remainder'
+		 * will become the 'request' for a next call.
+		 */
+		ind = 1 - ind;
+	}
+}
+
diff --git a/lib/librte_eal/unix/meson.build b/lib/librte_eal/unix/meson.build
index 5734f26ad..d13e66663 100644
--- a/lib/librte_eal/unix/meson.build
+++ b/lib/librte_eal/unix/meson.build
@@ -4,4 +4,5 @@
 sources += files(
 	'eal_unix.c',
 	'eal_unix_memory.c',
+	'eal_timer.c',
 )
-- 
2.16.1.windows.4

[dpdk-dev] [PATCH v4 2/2] timer: support EAL functions on Windows

[Fady Bader]

Implemented the needed Windows eal timer functions.

Signed-off-by: Fady Bader <fady@mellanox.com>
---
 lib/librte_eal/common/meson.build       |  1 +
 lib/librte_eal/windows/eal.c            |  6 +++
 lib/librte_eal/windows/eal_timer.c      | 96 +++++++++++++++++++++++++++++++++
 lib/librte_eal/windows/include/rte_os.h |  2 +
 lib/librte_eal/windows/meson.build      |  1 +
 5 files changed, 106 insertions(+)
 create mode 100644 lib/librte_eal/windows/eal_timer.c

diff --git a/lib/librte_eal/common/meson.build b/lib/librte_eal/common/meson.build
index 9bb234009..91c1e3469 100644
--- a/lib/librte_eal/common/meson.build
+++ b/lib/librte_eal/common/meson.build
@@ -21,6 +21,7 @@ if is_windows
 		'eal_common_string_fns.c',
 		'eal_common_tailqs.c',
 		'eal_common_thread.c',
+		'eal_common_timer.c',
 		'malloc_elem.c',
 		'malloc_heap.c',
 		'rte_malloc.c',
diff --git a/lib/librte_eal/windows/eal.c b/lib/librte_eal/windows/eal.c
index 38f17f09c..32853fbac 100644
--- a/lib/librte_eal/windows/eal.c
+++ b/lib/librte_eal/windows/eal.c
@@ -400,6 +400,12 @@ rte_eal_init(int argc, char **argv)
 		return -1;
 	}
 
+	if (rte_eal_timer_init() < 0) {
+		rte_eal_init_alert("Cannot init TSC timer");
+		rte_errno = EFAULT;
+		return -1;
+	}
+
 	eal_thread_init_master(rte_config.master_lcore);
 
 	RTE_LCORE_FOREACH_SLAVE(i) {
diff --git a/lib/librte_eal/windows/eal_timer.c b/lib/librte_eal/windows/eal_timer.c
new file mode 100644
index 000000000..108f66b54
--- /dev/null
+++ b/lib/librte_eal/windows/eal_timer.c
@@ -0,0 +1,96 @@
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright 2020 Mellanox Technologies, Ltd
+ */
+#include <inttypes.h>
+#include <time.h>
+
+#include <rte_windows.h>
+#include <rte_common.h>
+#include <rte_log.h>
+#include <rte_cycles.h>
+#include <rte_eal.h>
+#include <rte_errno.h>
+
+#define US_PER_SEC 1E6
+#define CYC_PER_10MHZ 1E7
+
+/* The frequency of the RDTSC timer resolution */
+static uint64_t eal_tsc_resolution_hz;
+
+void
+rte_delay_us_sleep(unsigned int us)
+{
+	HANDLE timer;
+	LARGE_INTEGER due_time;
+
+	/* create waitable timer */
+	timer = CreateWaitableTimer(NULL, TRUE, NULL);
+	if (!timer) {
+		RTE_LOG_WIN32_ERR("CreateWaitableTimer()");
+		rte_errno = ENOMEM;
+		return;
+	}
+
+	/*
+	 * due_time's uom is 100 ns, multiply by 10 to convert to microseconds
+	 * set us microseconds time for timer
+	 */
+	due_time.QuadPart = -(us * 10);
+	if (!SetWaitableTimer(timer, &due_time, 0, NULL, NULL, FALSE)) {
+		CloseHandle(timer);
+		RTE_LOG_WIN32_ERR("SetWaitableTimer()");
+		rte_errno = EINVAL;
+		return;
+	}
+	/* start wait for timer for us microseconds */
+	WaitForSingleObject(timer, INFINITE);
+	CloseHandle(timer);
+}
+
+uint64_t
+get_tsc_freq(void)
+{
+	LARGE_INTEGER t_start, t_end, elapsed_us;
+	LARGE_INTEGER frequency;
+	uint64_t tsc_hz;
+
+	if (QueryPerformanceFrequency(&frequency) == 0) {
+		RTE_LOG_WIN32_ERR("QueryPerformanceFrequency()");
+		return 0;
+	}
+
+	if (QueryPerformanceCounter(&t_start) != 0) {
+		uint64_t end, start = rte_get_tsc_cycles();
+
+		rte_delay_us(US_PER_SEC / 10); /* 1/10 second */
+
+		QueryPerformanceCounter(&t_end);
+		end = rte_get_tsc_cycles();
+
+		elapsed_us.QuadPart = t_end.QuadPart - t_start.QuadPart;
+
+		/*
+		 * To guard against loss-of-precision, convert to microseconds
+		 * *before* dividing by ticks-per-second.
+		 */
+		elapsed_us.QuadPart *= US_PER_SEC;
+		elapsed_us.QuadPart /= frequency.QuadPart;
+
+		double secs = ((double)elapsed_us.QuadPart)/US_PER_SEC;
+		tsc_hz = (uint64_t)((end - start)/secs);
+		/* Round up to 10Mhz. 1E7 ~ 10Mhz */
+		return RTE_ALIGN_MUL_NEAR(tsc_hz, CYC_PER_10MHZ);
+	}
+
+	RTE_LOG_WIN32_ERR("QueryPerformanceCounter()");
+	return 0;
+}
+
+
+int
+rte_eal_timer_init(void)
+{
+	set_tsc_freq();
+	return 0;
+}
+
diff --git a/lib/librte_eal/windows/include/rte_os.h b/lib/librte_eal/windows/include/rte_os.h
index 62805a307..3b63a37cb 100644
--- a/lib/librte_eal/windows/include/rte_os.h
+++ b/lib/librte_eal/windows/include/rte_os.h
@@ -24,6 +24,8 @@ extern "C" {
 #define PATH_MAX _MAX_PATH
 #endif
 
+#define sleep(x) Sleep(1000 * (x))
+
 #define strerror_r(a, b, c) strerror_s(b, c, a)
 
 /* strdup is deprecated in Microsoft libc and _strdup is preferred */
diff --git a/lib/librte_eal/windows/meson.build b/lib/librte_eal/windows/meson.build
index 0bd56cd8f..769cde797 100644
--- a/lib/librte_eal/windows/meson.build
+++ b/lib/librte_eal/windows/meson.build
@@ -12,6 +12,7 @@ sources += files(
 	'eal_memory.c',
 	'eal_mp.c',
 	'eal_thread.c',
+	'eal_timer.c',
 	'getopt.c',
 )
 
-- 
2.16.1.windows.4

Re: [dpdk-dev] [PATCH v4 2/2] timer: support EAL functions on Windows

[Dmitry Kozlyuk]

Getting extremely volatile results from get_tsc_hz(). Here's what I get from
10 successive calls:

freq=2660000000
freq=3220000000
freq=3740000000
freq=3870000000
freq=3830000000
freq=4060000000
freq=3370000000
freq=3820000000
freq=7370000000
freq=4970000000

Please see the last comment for the reason (and other comments inline).

On 2020-05-06 15:01 GMT+0300 Fady Bader wrote:
> Implemented the needed Windows eal timer functions.
> 
> Signed-off-by: Fady Bader <fady@mellanox.com>
> ---
[snip]
> diff --git a/lib/librte_eal/windows/eal_timer.c b/lib/librte_eal/windows/eal_timer.c
> new file mode 100644
> index 000000000..108f66b54
> --- /dev/null
> +++ b/lib/librte_eal/windows/eal_timer.c
> @@ -0,0 +1,96 @@
> +/* SPDX-License-Identifier: BSD-3-Clause
> + * Copyright 2020 Mellanox Technologies, Ltd
> + */
> +#include <inttypes.h>
> +#include <time.h>
> +
> +#include <rte_windows.h>
> +#include <rte_common.h>
> +#include <rte_log.h>
> +#include <rte_cycles.h>
> +#include <rte_eal.h>
> +#include <rte_errno.h>

#include "eal_private.h", without it:

../../../lib/librte_eal/windows/eal_timer.c: In function ‘rte_eal_timer_init’:
../../../lib/librte_eal/windows/eal_timer.c:108:2: warning: implicit declaration of function ‘set_tsc_freq’; did you mean ‘get_tsc_freq’? [-Wimplicit-function-declaration]
  108 |  set_tsc_freq();

> +
> +#define US_PER_SEC 1E6
> +#define CYC_PER_10MHZ 1E7
> +
> +/* The frequency of the RDTSC timer resolution */
> +static uint64_t eal_tsc_resolution_hz;
> +

At top level:
../../../lib/librte_eal/windows/eal_timer.c:20:17: warning: ‘eal_tsc_resolution_hz’ defined but not used [-Wunused-variable]
   20 | static uint64_t eal_tsc_resolution_hz;

Note: set_tsc_freq() already caches frequency you calculate here.

> +	due_time.QuadPart = -(us * 10);
> +	if (!SetWaitableTimer(timer, &due_time, 0, NULL, NULL, FALSE)) {
> +		CloseHandle(timer);
> +		RTE_LOG_WIN32_ERR("SetWaitableTimer()");

RTE_LOG_WIN32_ERR() uses GetLastError(), the value of which may be overridden
by a successful call to CloseHandle().

> +		rte_errno = EINVAL;
> +		return;
> +	}
> +	/* start wait for timer for us microseconds */
> +	WaitForSingleObject(timer, INFINITE);
> +	CloseHandle(timer);
> +}
> +
> +uint64_t
> +get_tsc_freq(void)
> +{
> +	LARGE_INTEGER t_start, t_end, elapsed_us;
> +	LARGE_INTEGER frequency;
> +	uint64_t tsc_hz;
> +
> +	if (QueryPerformanceFrequency(&frequency) == 0) {
> +		RTE_LOG_WIN32_ERR("QueryPerformanceFrequency()");
> +		return 0;
> +	}
> +
> +	if (QueryPerformanceCounter(&t_start) != 0) {

Per MSDN, QueryPerformanceFrequency() and QueryPerformanceCounter() always
succeed on all supported Windows versions.

> +		uint64_t end, start = rte_get_tsc_cycles();
> +
> +		rte_delay_us(US_PER_SEC / 10); /* 1/10 second */

Did you mean rte_delay_us_sleep()? rte_delay_us() assumes TSC frequency is
already available. With this fix, results become stable.

-- 
Dmitry Kozlyuk

Re: [dpdk-dev] [PATCH v4 1/2] timer: move from common to Unix directory

[Dmitry Kozlyuk]

On 2020-05-06 15:01 GMT+0300 Fady Bader wrote:
[snip]
> diff --git a/lib/librte_eal/unix/meson.build b/lib/librte_eal/unix/meson.build
> index 5734f26ad..d13e66663 100644
> --- a/lib/librte_eal/unix/meson.build
> +++ b/lib/librte_eal/unix/meson.build
> @@ -4,4 +4,5 @@
>  sources += files(
>  	'eal_unix.c',
>  	'eal_unix_memory.c',
> +	'eal_timer.c',
>  )
> -- 
> 2.16.1.windows.4
> 

I suggest creating unix/ directory by this patch to break dependency on
memory management series, because its review will clearly take longer. I'd
better rebase MM series after this one will get merged.

-- 
Dmitry Kozlyuk