From a51639cc720aa17922d4b479e9961169f3a36c64 Mon Sep 17 00:00:00 2001 From: Ilya Maximets Date: Wed, 10 Oct 2018 17:12:19 +0300 Subject: [PATCH] eal: add nanosleep based delay function Add a new rte_delay_us_sleep() function that uses nanosleep(). This function can be used by applications to not implement their own nanosleep() based callback and by internal DPDK code if CPU non-blocking delay needed. Signed-off-by: Ilya Maximets Reviewed-by: Ferruh Yigit --- lib/librte_eal/common/eal_common_timer.c | 24 +++++++++ .../common/include/generic/rte_cycles.h | 11 ++++ lib/librte_eal/rte_eal_version.map | 1 + test/test/autotest_data.py | 6 +++ test/test/meson.build | 1 + test/test/test_cycles.c | 51 ++++++++++++++----- 6 files changed, 80 insertions(+), 14 deletions(-) diff --git a/lib/librte_eal/common/eal_common_timer.c b/lib/librte_eal/common/eal_common_timer.c index 2e2b770fb9..dcf26bfead 100644 --- a/lib/librte_eal/common/eal_common_timer.c +++ b/lib/librte_eal/common/eal_common_timer.c @@ -7,9 +7,11 @@ #include #include #include +#include #include #include +#include #include #include #include @@ -31,6 +33,28 @@ rte_delay_us_block(unsigned int us) rte_pause(); } +void __rte_experimental +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/common/include/generic/rte_cycles.h b/lib/librte_eal/common/include/generic/rte_cycles.h index 0ff1af5047..ac379e8780 100644 --- a/lib/librte_eal/common/include/generic/rte_cycles.h +++ b/lib/librte_eal/common/include/generic/rte_cycles.h @@ -13,6 +13,7 @@ */ #include +#include #include #include @@ -157,6 +158,16 @@ rte_delay_ms(unsigned ms) */ void rte_delay_us_block(unsigned int us); +/** + * Delay function that uses system sleep. + * Does not block the CPU core. + * + * @param us + * Number of microseconds to wait. + */ +void __rte_experimental +rte_delay_us_sleep(unsigned int us); + /** * Replace rte_delay_us with user defined function. * diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map index 32fe2ba40e..f4a2b38fdb 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -273,6 +273,7 @@ EXPERIMENTAL { rte_class_register; rte_class_unregister; rte_ctrl_thread_create; + rte_delay_us_sleep; rte_dev_event_callback_process; rte_dev_event_callback_register; rte_dev_event_callback_unregister; diff --git a/test/test/autotest_data.py b/test/test/autotest_data.py index 0df686ad15..e7df68fc7d 100644 --- a/test/test/autotest_data.py +++ b/test/test/autotest_data.py @@ -278,6 +278,12 @@ parallel_test_list = [ "Func": default_autotest, "Report": None, }, + { + "Name": "Sleep delay", + "Command": "delay_us_sleep_autotest", + "Func": default_autotest, + "Report": None, + }, { "Name": "Rawdev autotest", "Command": "rawdev_autotest", diff --git a/test/test/meson.build b/test/test/meson.build index 1c1fcd71bf..b707547ea8 100644 --- a/test/test/meson.build +++ b/test/test/meson.build @@ -149,6 +149,7 @@ test_names = [ 'cryptodev_octeontx_autotest', 'cycles_autotest', 'debug_autotest', + 'delay_us_sleep_autotest', 'devargs_autotest', 'distributor_autotest', 'distributor_perf_autotest', diff --git a/test/test/test_cycles.c b/test/test/test_cycles.c index 149f60b078..c78e6a5b12 100644 --- a/test/test/test_cycles.c +++ b/test/test/test_cycles.c @@ -23,6 +23,30 @@ * of cycles is correct with regard to the frequency of the timer. */ +static int +check_wait_one_second(void) +{ + uint64_t cycles, prev_cycles; + uint64_t hz = rte_get_timer_hz(); + uint64_t max_inc = (hz / 100); /* 10 ms max between 2 reads */ + + /* check that waiting 1 second is precise */ + prev_cycles = rte_get_timer_cycles(); + rte_delay_us(1000000); + cycles = rte_get_timer_cycles(); + + if ((uint64_t)(cycles - prev_cycles) > (hz + max_inc)) { + printf("delay_us is not accurate: too long\n"); + return -1; + } + if ((uint64_t)(cycles - prev_cycles) < (hz - max_inc)) { + printf("delay_us is not accurate: too short\n"); + return -1; + } + + return 0; +} + static int test_cycles(void) { @@ -43,24 +67,23 @@ test_cycles(void) prev_cycles = cycles; } - /* check that waiting 1 second is precise */ - prev_cycles = rte_get_timer_cycles(); - rte_delay_us(1000000); - cycles = rte_get_timer_cycles(); + return check_wait_one_second(); +} - if ((uint64_t)(cycles - prev_cycles) > (hz + max_inc)) { - printf("delay_us is not accurate: too long\n"); - return -1; - } - if ((uint64_t)(cycles - prev_cycles) < (hz - max_inc)) { - printf("delay_us is not accurate: too short\n"); - return -1; - } +REGISTER_TEST_COMMAND(cycles_autotest, test_cycles); - return 0; +/* + * One second precision test with rte_delay_us_sleep. + */ + +static int +test_delay_us_sleep(void) +{ + rte_delay_us_callback_register(rte_delay_us_sleep); + return check_wait_one_second(); } -REGISTER_TEST_COMMAND(cycles_autotest, test_cycles); +REGISTER_TEST_COMMAND(delay_us_sleep_autotest, test_delay_us_sleep); /* * rte_delay_us_callback test -- 2.20.1