X-Git-Url: http://git.droids-corp.org/?a=blobdiff_plain;f=lib%2Flibrte_eal%2Finclude%2Fgeneric%2Frte_power_intrinsics.h;h=dddca3d41ce1efbb970530d2f05896487982f3ae;hb=8d63961fc7137cab823f85a50ee82779792f21e4;hp=3ad53068d5c11fd876d64d57d40126346ddb3230;hpb=6a17919b0e2a482e0b3f505a048a2a3383e979e3;p=dpdk.git diff --git a/lib/librte_eal/include/generic/rte_power_intrinsics.h b/lib/librte_eal/include/generic/rte_power_intrinsics.h index 3ad53068d5..dddca3d41c 100644 --- a/lib/librte_eal/include/generic/rte_power_intrinsics.h +++ b/lib/librte_eal/include/generic/rte_power_intrinsics.h @@ -20,29 +20,35 @@ struct rte_power_monitor_cond { volatile void *addr; /**< Address to monitor for changes */ - uint64_t val; /**< Before attempting the monitoring, the address - * may be read and compared against this value. - **/ - uint64_t mask; /**< 64-bit mask to extract current value from addr */ - uint8_t data_sz; /**< Data size (in bytes) that will be used to compare - * expected value with the memory address. Can be 1, - * 2, 4, or 8. Supplying any other value will lead to - * undefined result. */ + uint64_t val; /**< If the `mask` is non-zero, location pointed + * to by `addr` will be read and compared + * against this value. + */ + uint64_t mask; /**< 64-bit mask to extract value read from `addr` */ + uint8_t size; /**< Data size (in bytes) that will be used to compare + * expected value (`val`) with data read from the + * monitored memory location (`addr`). Can be 1, 2, + * 4, or 8. Supplying any other value will result in + * an error. + */ }; /** * @warning - * @b EXPERIMENTAL: this API may change without prior notice + * @b EXPERIMENTAL: this API may change without prior notice. * * Monitor specific address for changes. This will cause the CPU to enter an * architecture-defined optimized power state until either the specified * memory address is written to, a certain TSC timestamp is reached, or other * reasons cause the CPU to wake up. * - * Additionally, an `expected` 64-bit value and 64-bit mask are provided. If - * mask is non-zero, the current value pointed to by the `p` pointer will be - * checked against the expected value, and if they match, the entering of - * optimized power state may be aborted. + * Additionally, an expected value (`pmc->val`), mask (`pmc->mask`), and data + * size (`pmc->size`) are provided in the `pmc` power monitoring condition. If + * the mask is non-zero, the current value pointed to by the `pmc->addr` pointer + * will be read and compared against the expected value, and if they match, the + * entering of optimized power state will be aborted. This is intended to + * prevent the CPU from entering optimized power state and waiting on a write + * that has already happened by the time this API is called. * * @warning It is responsibility of the user to check if this function is * supported at runtime using `rte_cpu_get_intrinsics_support()` API call. @@ -61,48 +67,29 @@ struct rte_power_monitor_cond { __rte_experimental int rte_power_monitor(const struct rte_power_monitor_cond *pmc, const uint64_t tsc_timestamp); + /** * @warning - * @b EXPERIMENTAL: this API may change without prior notice + * @b EXPERIMENTAL: this API may change without prior notice. * - * Monitor specific address for changes. This will cause the CPU to enter an - * architecture-defined optimized power state until either the specified - * memory address is written to, a certain TSC timestamp is reached, or other - * reasons cause the CPU to wake up. + * Wake up a specific lcore that is in a power optimized state and is monitoring + * an address. * - * Additionally, an `expected` 64-bit value and 64-bit mask are provided. If - * mask is non-zero, the current value pointed to by the `p` pointer will be - * checked against the expected value, and if they match, the entering of - * optimized power state may be aborted. - * - * This call will also lock a spinlock on entering sleep, and release it on - * waking up the CPU. - * - * @warning It is responsibility of the user to check if this function is - * supported at runtime using `rte_cpu_get_intrinsics_support()` API call. + * @note It is safe to call this function if the lcore in question is not + * sleeping. The function will have no effect. * - * @param pmc - * The monitoring condition structure. - * @param tsc_timestamp - * Maximum TSC timestamp to wait for. Note that the wait behavior is - * architecture-dependent. - * @param lck - * A spinlock that must be locked before entering the function, will be - * unlocked while the CPU is sleeping, and will be locked again once the CPU - * wakes up. + * @note This function will *not* wake up a core that is in a power optimized + * state due to calling `rte_power_pause`. * - * @return - * 0 on success - * -EINVAL on invalid parameters - * -ENOTSUP if unsupported + * @param lcore_id + * Lcore ID of a sleeping thread. */ __rte_experimental -int rte_power_monitor_sync(const struct rte_power_monitor_cond *pmc, - const uint64_t tsc_timestamp, rte_spinlock_t *lck); +int rte_power_monitor_wakeup(const unsigned int lcore_id); /** * @warning - * @b EXPERIMENTAL: this API may change without prior notice + * @b EXPERIMENTAL: this API may change without prior notice. * * Enter an architecture-defined optimized power state until a certain TSC * timestamp is reached.