From: Daniel Mrzyglod Date: Fri, 13 Nov 2015 16:09:08 +0000 (+0000) Subject: eal: add helpers for time conversions X-Git-Tag: spdx-start~8061 X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=b6fd85cd65157feca2b4287a33fe1bc631782eef;p=dpdk.git eal: add helpers for time conversions Add common functions and structures to handle time, and cycle counts which will be used for PTP processing. Signed-off-by: Daniel Mrzyglod Signed-off-by: Pablo de Lara Reviewed-by: John McNamara --- diff --git a/lib/librte_eal/common/Makefile b/lib/librte_eal/common/Makefile index 0c43d6afa2..8508473700 100644 --- a/lib/librte_eal/common/Makefile +++ b/lib/librte_eal/common/Makefile @@ -40,7 +40,7 @@ INC += rte_string_fns.h rte_version.h INC += rte_eal_memconfig.h rte_malloc_heap.h INC += rte_hexdump.h rte_devargs.h rte_dev.h INC += rte_pci_dev_feature_defs.h rte_pci_dev_features.h -INC += rte_malloc.h +INC += rte_malloc.h rte_time.h ifeq ($(CONFIG_RTE_INSECURE_FUNCTION_WARNING),y) INC += rte_warnings.h diff --git a/lib/librte_eal/common/include/rte_time.h b/lib/librte_eal/common/include/rte_time.h new file mode 100644 index 0000000000..4b13b9c1ca --- /dev/null +++ b/lib/librte_eal/common/include/rte_time.h @@ -0,0 +1,122 @@ +/*- + * BSD LICENSE + * + * Copyright(c) 2015 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. + */ + +#define NSEC_PER_SEC 1000000000L + +/** + * Structure to hold the parameters of a running cycle counter to assist + * in converting cycles to nanoseconds. + */ +struct rte_timecounter { + /** Last cycle counter value read. */ + uint64_t cycle_last; + /** Nanoseconds count. */ + uint64_t nsec; + /** Bitmask separating nanosecond and sub-nanoseconds. */ + uint64_t nsec_mask; + /** Sub-nanoseconds count. */ + uint64_t nsec_frac; + /** Bitmask for two's complement substraction of non-64 bit counters. */ + uint64_t cc_mask; + /** Cycle to nanosecond divisor (power of two). */ + uint32_t cc_shift; +}; + +/** + * Converts cyclecounter cycles to nanoseconds. + */ +static inline uint64_t +rte_cyclecounter_cycles_to_ns(struct rte_timecounter *tc, uint64_t cycles) +{ + uint64_t ns; + + /* Add fractional nanoseconds. */ + ns = cycles + tc->nsec_frac; + tc->nsec_frac = ns & tc->nsec_mask; + + /* Shift to get only nanoseconds. */ + return ns >> tc->cc_shift; +} + +/** + * Update the internal nanosecond count in the structure. + */ +static inline uint64_t +rte_timecounter_update(struct rte_timecounter *tc, uint64_t cycle_now) +{ + uint64_t cycle_delta, ns_offset; + + /* Calculate the delta since the last call. */ + if (tc->cycle_last <= cycle_now) + cycle_delta = (cycle_now - tc->cycle_last) & tc->cc_mask; + else + /* Handle cycle counts that have wrapped around . */ + cycle_delta = (~(tc->cycle_last - cycle_now) & tc->cc_mask) + 1; + + /* Convert to nanoseconds. */ + ns_offset = rte_cyclecounter_cycles_to_ns(tc, cycle_delta); + + /* Store current cycle counter for next call. */ + tc->cycle_last = cycle_now; + + /* Update the nanosecond count. */ + tc->nsec += ns_offset; + + return tc->nsec; +} + +/** + * Convert from timespec structure into nanosecond units. + */ +static inline uint64_t +rte_timespec_to_ns(const struct timespec *ts) +{ + return ((uint64_t) ts->tv_sec * NSEC_PER_SEC) + ts->tv_nsec; +} + +/** + * Convert from nanosecond units into timespec structure. + */ +static inline struct timespec +rte_ns_to_timespec(uint64_t nsec) +{ + struct timespec ts = {0, 0}; + + if (nsec == 0) + return ts; + + ts.tv_sec = nsec / NSEC_PER_SEC; + ts.tv_nsec = nsec % NSEC_PER_SEC; + + return ts; +}