rte_power_intrinsics.h - Man Page

#define RTE_POWER_MONITOR_OPAQUE_SZ   4

typedef int(* rte_power_monitor_clb_t) (const uint64_t val, const uint64_t opaque[RTE_POWER_MONITOR_OPAQUE_SZ])

int rte_power_monitor (const struct rte_power_monitor_cond *pmc, const uint64_t tsc_timestamp)
int rte_power_monitor_wakeup (const unsigned int lcore_id)
int rte_power_pause (const uint64_t tsc_timestamp)
int rte_power_monitor_multi (const struct rte_power_monitor_cond pmc[], const uint32_t num, const uint64_t tsc_timestamp)

Size of the opaque data in monitor condition

Definition at line 21 of file rte_power_intrinsics.h.

Callback definition for monitoring conditions. Callbacks with this signature will be used by rte_power_monitor() to check if the entering of power optimized state should be aborted.

Parameters

val The value read from memory.
opaque Callback-specific data.

Returns

Definition at line 37 of file rte_power_intrinsics.h.

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 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.

Parameters

pmc The monitoring condition structure.
tsc_timestamp Maximum TSC timestamp to wait for. Note that the wait behavior is architecture-dependent.

Returns

Wake up a specific lcore that is in a power optimized state and is monitoring an address.

Note

It is safe to call this function if the lcore in question is not sleeping. The function will have no effect.

This function will not wake up a core that is in a power optimized state due to calling rte_power_pause.

Parameters

lcore_id Lcore ID of a sleeping thread.

Enter an architecture-defined optimized power state until a certain TSC timestamp is reached.

Warning

It is responsibility of the user to check if this function is supported at runtime using rte_cpu_get_intrinsics_support() API call.

Parameters

tsc_timestamp Maximum TSC timestamp to wait for. Note that the wait behavior is architecture-dependent.

Returns

Monitor a set of addresses for changes. This will cause the CPU to enter an architecture-defined optimized power state until either one of the specified memory addresses is written to, a certain TSC timestamp is reached, or other reasons cause the CPU to wake up.

Additionally, expected 64-bit values and 64-bit masks 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 do not match, the entering of optimized power state may be aborted.

Warning

It is responsibility of the user to check if this function is supported at runtime using rte_cpu_get_intrinsics_support() API call. Failing to do so may result in an illegal CPU instruction error.

Parameters

pmc An array of monitoring condition structures.
num Length of the pmc array.
tsc_timestamp Maximum TSC timestamp to wait for. Note that the wait behavior is architecture-dependent.

Returns