mirror of
https://github.com/apache/nuttx.git
synced 2025-12-07 01:44:23 +08:00
Nuttx currently has 2 types of sleep interfaces: 1. Signal-scheduled sleep: nxsig_sleep() / nxsig_usleep() / nxsig_nanosleep() Weaknesses: a. Signal-dependent: The signal-scheduled sleep method is bound to the signal framework, while some driver sleep operations do not depend on signals. b. Timespec conversion: Signal-scheduled sleep involves timespec conversion, which has a significant impact on performance. 2. Busy sleep: up_mdelay() / up_udelay() Weaknesses: a. Does not actively trigger scheduling, occupy the CPU loading. 3. New interfaces: Scheduled sleep: nxsched_sleep() / nxsched_usleep() / nxsched_msleep() / nxsched_ticksleep() Strengths: a. Does not depend on the signal framework. b. Tick-based, without additional computational overhead. Currently, the Nuttx driver framework extensively uses nxsig_* interfaces. However, the driver does not need to rely on signals or timespec conversion. Therefore, a new set of APIs is added to reduce dependencies on other modules. (This PR also aims to make signals optional, further reducing the code size of Nuttx.) Signed-off-by: chao an <anchao.archer@bytedance.com>