PSB CSYNC

Profiling Synchronization Barrier. This instruction is a barrier that ensures that all existing profiling data for the current PE has been formatted, and profiling buffer addresses have been translated such that all writes to the profiling buffer have been initiated. A following DSB instruction completes when the writes to the profiling buffer have completed.

System
(ARMv8.2)

313029282726252423222120191817161514131211109876543210
11010101000000110010001000111111
CRmop2

System

PSB CSYNC

SystemHintOp op; case CRm:op2 of when '0000 000' op = SystemHintOp_NOP; when '0000 001' op = SystemHintOp_YIELD; when '0000 010' op = SystemHintOp_WFE; when '0000 011' op = SystemHintOp_WFI; when '0000 100' op = SystemHintOp_SEV; when '0000 101' op = SystemHintOp_SEVL; when '0010 000' op = if HaveRASExt() then SystemHintOp_ESB else SystemHintOp_NOP; when '0010 001' op = if HaveStatisticalProfiling() then SystemHintOp_PSB else SystemHintOp_NOP; otherwise op = SystemHintOp_NOP;

Operation

case op of when SystemHintOp_YIELD Hint_Yield(); when SystemHintOp_WFE if IsEventRegisterSet() then ClearEventRegister(); else if PSTATE.EL == EL0 then // Check for traps described by the OS which may be EL1 or EL2. AArch64.CheckForWFxTrap(EL1, TRUE); if HaveEL(EL2) && !IsSecure() && PSTATE.EL IN {EL0,EL1} && !IsInHost() then // Check for traps described by the Hypervisor. AArch64.CheckForWFxTrap(EL2, TRUE); if HaveEL(EL3) && PSTATE.EL != EL3 then // Check for traps described by the Secure Monitor. AArch64.CheckForWFxTrap(EL3, TRUE); WaitForEvent(); when SystemHintOp_WFI if !InterruptPending() then if PSTATE.EL == EL0 then // Check for traps described by the OS which may be EL1 or EL2. AArch64.CheckForWFxTrap(EL1, FALSE); if HaveEL(EL2) && !IsSecure() && PSTATE.EL IN {EL0,EL1} && !IsInHost() then // Check for traps described by the Hypervisor. AArch64.CheckForWFxTrap(EL2, FALSE); if HaveEL(EL3) && PSTATE.EL != EL3 then // Check for traps described by the Secure Monitor. AArch64.CheckForWFxTrap(EL3, FALSE); WaitForInterrupt(); when SystemHintOp_SEV SendEvent(); when SystemHintOp_SEVL SendEventLocal(); when SystemHintOp_ESB ErrorSynchronizationBarrier(MBReqDomain_FullSystem, MBReqTypes_All); AArch64.ESBOperation(); if HaveEL(EL2) && !IsSecure() && PSTATE.EL IN {EL0,EL1} then AArch64.vESBOperation(); TakeUnmaskedSErrorInterrupts(); when SystemHintOp_PSB ProfilingSynchronizationBarrier(); otherwise // do nothing


Internal version only: isa v25.07, AdvSIMD v23.0, pseudocode v31.3

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