F: lib/librte_eal/common/include/generic/rte_ticketlock.h
F: app/test/test_ticketlock.c
+Pseudo-random Number Generation
+M: Mattias Rönnblom <mattias.ronnblom@ericsson.com>
+F: lib/librte_eal/common/include/rte_random.h
+F: lib/librte_eal/common/rte_random.c
+F: app/test/test_rand_perf.c
+
ARM v7
M: Jan Viktorin <viktorin@rehivetech.com>
M: Gavin Hu <gavin.hu@arm.com>
SRCS-y += test_reciprocal_division_perf.c
SRCS-y += test_fbarray.c
SRCS-y += test_external_mem.c
+SRCS-y += test_rand_perf.c
SRCS-y += test_ring.c
SRCS-y += test_ring_perf.c
'test_power_acpi_cpufreq.c',
'test_power_kvm_vm.c',
'test_prefetch.c',
+ 'test_rand_perf.c',
'test_rcu_qsbr.c',
'test_rcu_qsbr_perf.c',
'test_reciprocal_division.c',
'pmd_perf_autotest',
'stack_perf_autotest',
'stack_lf_perf_autotest',
+ 'rand_perf_autotest',
]
driver_test_names = [
--- /dev/null
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019 Ericsson AB
+ */
+
+#include <inttypes.h>
+#include <stdio.h>
+
+#include <rte_common.h>
+#include <rte_cycles.h>
+#include <rte_random.h>
+
+#include "test.h"
+
+static volatile uint64_t vsum;
+
+#define ITERATIONS (100000000)
+
+enum rand_type {
+ rand_type_64
+};
+
+static const char *
+rand_type_desc(enum rand_type rand_type)
+{
+ switch (rand_type) {
+ case rand_type_64:
+ return "Full 64-bit [rte_rand()]";
+ default:
+ return NULL;
+ }
+}
+
+static __rte_always_inline void
+test_rand_perf_type(enum rand_type rand_type)
+{
+ uint64_t start;
+ uint32_t i;
+ uint64_t end;
+ uint64_t sum = 0;
+ uint64_t op_latency;
+
+ start = rte_rdtsc();
+
+ for (i = 0; i < ITERATIONS; i++) {
+ switch (rand_type) {
+ case rand_type_64:
+ sum += rte_rand();
+ break;
+ }
+ }
+
+ end = rte_rdtsc();
+
+ /* to avoid an optimizing compiler removing the whole loop */
+ vsum = sum;
+
+ op_latency = (end - start) / ITERATIONS;
+
+ printf("%s: %"PRId64" TSC cycles/op\n", rand_type_desc(rand_type),
+ op_latency);
+}
+
+static int
+test_rand_perf(void)
+{
+ rte_srand(42);
+
+ printf("Pseudo-random number generation latencies:\n");
+
+ test_rand_perf_type(rand_type_64);
+
+ return 0;
+}
+
+REGISTER_TEST_COMMAND(rand_perf_autotest, test_rand_perf);
Also, make sure to start the actual text at the margin.
=========================================================
+* **Updated the EAL Pseudo-random Number Generator.**
+
+ The lrand48()-based rte_rand() function is replaced with a
+ DPDK-native combined Linear Feedback Shift Register (LFSR)
+ pseudo-random number generator (PRNG).
+
+ This new PRNG implementation is multi-thread safe, provides
+ higher-quality pseudo-random numbers (including full 64 bit
+ support) and improved performance.
+
* **Updated the bnxt PMD.**
Updated the bnxt PMD. The major enhancements include:
#endif
#include <stdint.h>
-#include <stdlib.h>
/**
* Seed the pseudo-random generator.
* value. It may need to be re-seeded by the user with a real random
* value.
*
+ * This function is not multi-thread safe in regards to other
+ * rte_srand() calls, nor is it in relation to concurrent rte_rand()
+ * calls.
+ *
* @param seedval
* The value of the seed.
*/
-static inline void
-rte_srand(uint64_t seedval)
-{
- srand48((long)seedval);
-}
+void
+rte_srand(uint64_t seedval);
/**
* Get a pseudo-random value.
*
- * This function generates pseudo-random numbers using the linear
- * congruential algorithm and 48-bit integer arithmetic, called twice
- * to generate a 64-bit value.
+ * The generator is not cryptographically secure.
+ *
+ * If called from lcore threads, this function is thread-safe.
*
* @return
* A pseudo-random value between 0 and (1<<64)-1.
*/
-static inline uint64_t
-rte_rand(void)
-{
- uint64_t val;
- val = (uint64_t)lrand48();
- val <<= 32;
- val += (uint64_t)lrand48();
- return val;
-}
+uint64_t
+rte_rand(void);
#ifdef __cplusplus
}
'rte_keepalive.c',
'rte_malloc.c',
'rte_option.c',
+ 'rte_random.c',
'rte_reciprocal.c',
'rte_service.c'
)
--- /dev/null
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2019 Ericsson AB
+ */
+
+#include <stdlib.h>
+
+#include <rte_branch_prediction.h>
+#include <rte_cycles.h>
+#include <rte_eal.h>
+#include <rte_lcore.h>
+#include <rte_memory.h>
+#include <rte_random.h>
+
+struct rte_rand_state {
+ uint64_t z1;
+ uint64_t z2;
+ uint64_t z3;
+ uint64_t z4;
+ uint64_t z5;
+} __rte_cache_aligned;
+
+static struct rte_rand_state rand_states[RTE_MAX_LCORE];
+
+static uint32_t
+__rte_rand_lcg32(uint32_t *seed)
+{
+ *seed = 1103515245U * *seed + 12345U;
+
+ return *seed;
+}
+
+static uint64_t
+__rte_rand_lcg64(uint32_t *seed)
+{
+ uint64_t low;
+ uint64_t high;
+
+ /* A 64-bit LCG would have been much cleaner, but good
+ * multiplier/increments for such seem hard to come by.
+ */
+
+ low = __rte_rand_lcg32(seed);
+ high = __rte_rand_lcg32(seed);
+
+ return low | (high << 32);
+}
+
+static uint64_t
+__rte_rand_lfsr258_gen_seed(uint32_t *seed, uint64_t min_value)
+{
+ uint64_t res;
+
+ res = __rte_rand_lcg64(seed);
+
+ if (res < min_value)
+ res += min_value;
+
+ return res;
+}
+
+static void
+__rte_srand_lfsr258(uint64_t seed, struct rte_rand_state *state)
+{
+ uint32_t lcg_seed;
+
+ lcg_seed = (uint32_t)(seed ^ (seed >> 32));
+
+ state->z1 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 2UL);
+ state->z2 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 512UL);
+ state->z3 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 4096UL);
+ state->z4 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 131072UL);
+ state->z5 = __rte_rand_lfsr258_gen_seed(&lcg_seed, 8388608UL);
+}
+
+void
+rte_srand(uint64_t seed)
+{
+ unsigned int lcore_id;
+
+ /* add lcore_id to seed to avoid having the same sequence */
+ for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++)
+ __rte_srand_lfsr258(seed + lcore_id, &rand_states[lcore_id]);
+}
+
+static __rte_always_inline uint64_t
+__rte_rand_lfsr258_comp(uint64_t z, uint64_t a, uint64_t b, uint64_t c,
+ uint64_t d)
+{
+ return ((z & c) << d) ^ (((z << a) ^ z) >> b);
+}
+
+/* Based on L’Ecuyer, P.: Tables of maximally equidistributed combined
+ * LFSR generators.
+ */
+
+static __rte_always_inline uint64_t
+__rte_rand_lfsr258(struct rte_rand_state *state)
+{
+ state->z1 = __rte_rand_lfsr258_comp(state->z1, 1UL, 53UL,
+ 18446744073709551614UL, 10UL);
+ state->z2 = __rte_rand_lfsr258_comp(state->z2, 24UL, 50UL,
+ 18446744073709551104UL, 5UL);
+ state->z3 = __rte_rand_lfsr258_comp(state->z3, 3UL, 23UL,
+ 18446744073709547520UL, 29UL);
+ state->z4 = __rte_rand_lfsr258_comp(state->z4, 5UL, 24UL,
+ 18446744073709420544UL, 23UL);
+ state->z5 = __rte_rand_lfsr258_comp(state->z5, 3UL, 33UL,
+ 18446744073701163008UL, 8UL);
+
+ return state->z1 ^ state->z2 ^ state->z3 ^ state->z4 ^ state->z5;
+}
+
+static __rte_always_inline
+struct rte_rand_state *__rte_rand_get_state(void)
+{
+ unsigned int lcore_id;
+
+ lcore_id = rte_lcore_id();
+
+ if (unlikely(lcore_id == LCORE_ID_ANY))
+ lcore_id = rte_get_master_lcore();
+
+ return &rand_states[lcore_id];
+}
+
+uint64_t
+rte_rand(void)
+{
+ struct rte_rand_state *state;
+
+ state = __rte_rand_get_state();
+
+ return __rte_rand_lfsr258(state);
+}
+
+RTE_INIT(rte_rand_init)
+{
+ rte_srand(rte_get_timer_cycles());
+}
SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_keepalive.c
SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_option.c
SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_service.c
+SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_random.c
SRCS-$(CONFIG_RTE_EXEC_ENV_FREEBSD) += rte_reciprocal.c
# from arch dir
#endif
}
- rte_srand(rte_rdtsc());
-
/* in secondary processes, memory init may allocate additional fbarrays
* not present in primary processes, so to avoid any potential issues,
* initialize memzones first.
SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_keepalive.c
SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_option.c
SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_service.c
+SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_random.c
SRCS-$(CONFIG_RTE_EXEC_ENV_LINUX) += rte_reciprocal.c
# from arch dir
#endif
}
- rte_srand(rte_rdtsc());
-
if (rte_eal_log_init(logid, internal_config.syslog_facility) < 0) {
rte_eal_init_alert("Cannot init logging.");
rte_errno = ENOMEM;
rte_lcore_index;
rte_lcore_to_socket_id;
+ rte_rand;
+ rte_srand;
} DPDK_19.05;