GroupBarrier Usage Description

When two AIV tasks in the same CubeResGroupHandle object depend on each other, control synchronization by calling GroupBarrier. Assume that AIV B can start subsequent services only after AIV A completes task x. Here, AIV A is referred to as the Arrive group, and AIV B is referred to as the Wait group.

To use GroupBarrier-based group synchronization, perform the following steps:

1. Create a GroupBarrier object.
2. Call Arrive by the AIV to be waited for, and call Wait by the AIV that needs to wait.

1. Create a GroupBarrier object.

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   constexpr int32_t ARRIVE_NUM = 2; // Number of AIVs in the Arrive group. constexpr int32_t WAIT_NUM = 6; // Number of AIVs in the Wait group. // Create a GroupBarrier object. Users manage and clear the workspace. AscendC::GroupBarrier<AscendC::PipeMode::MTE3_MODE> barA(workspace, ARRIVE_NUM, WAIT_NUM);

2. Call Arrive by the AIV to be waited for, and call Wait by the AIV that needs to wait.

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   auto id = AscendC::GetBlockIdx(); if (id > 0 && id < ARRIVE_NUM) { //Various Vector compute logic, which is implemented by users. barA.Arrive(id); } else(id >= ARRIVE_NUM && id < ARRIVE_NUM + WAIT_NUM){ barA.Wait(id - ARRIVE_NUM); //Various Vector compute logic, which is implemented by users. }