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fastpath: fix branch predications

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All jump instructions to slowpath are unlikely executed
in fastpath, and this prevents polluting i-cache by pushing
it away.
This commit is contained in:
Luca(Wei) Chen 2020-02-10 10:51:01 +11:00 committed by Chen, Wei (Data61, Kensington NSW)
parent 62fcb7c9c4
commit feb3717e50
1 changed files with 5 additions and 6 deletions
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11
src/fastpath/fastpath.c
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@ -72,7 +72,7 @@ fastpath_call(word_t cptr, word_t msgInfo)
/* ensure we are not single stepping the destination in ia32 */
#if defined(CONFIG_HARDWARE_DEBUG_API) && defined(CONFIG_ARCH_IA32)
if (dest->tcbArch.tcbContext.breakpointState.single_step_enabled) {
if (unlikely(dest->tcbArch.tcbContext.breakpointState.single_step_enabled)) {
slowpath(SysCall);
}
#endif
@ -114,8 +114,7 @@ fastpath_call(word_t cptr, word_t msgInfo)
/* let gcc optimise this out for 1 domain */
dom = maxDom ? ksCurDomain : 0;
/* ensure only the idle thread or lower prio threads are present in the scheduler */
if (likely(dest->tcbPriority < NODE_STATE(ksCurThread->tcbPriority)) &&
!isHighestPrio(dom, dest->tcbPriority)) {
if (unlikely(dest->tcbPriority < NODE_STATE(ksCurThread->tcbPriority)) && !isHighestPrio(dom, dest->tcbPriority)) {
slowpath(SysCall);
}
@ -276,8 +275,8 @@ void fastpath_reply_recv(word_t cptr, word_t msgInfo)
#endif
/* Check there is nothing waiting on the notification */
if (NODE_STATE(ksCurThread)->tcbBoundNotification &&
notification_ptr_get_state(NODE_STATE(ksCurThread)->tcbBoundNotification) == NtfnState_Active) {
if (unlikely(NODE_STATE(ksCurThread)->tcbBoundNotification &&
notification_ptr_get_state(NODE_STATE(ksCurThread)->tcbBoundNotification) == NtfnState_Active)) {
slowpath(SysReplyRecv);
}
@ -314,7 +313,7 @@ void fastpath_reply_recv(word_t cptr, word_t msgInfo)
/* ensure we are not single stepping the caller in ia32 */
#if defined(CONFIG_HARDWARE_DEBUG_API) && defined(CONFIG_ARCH_IA32)
if (caller->tcbArch.tcbContext.breakpointState.single_step_enabled) {
if (unlikely(caller->tcbArch.tcbContext.breakpointState.single_step_enabled)) {
slowpath(SysReplyRecv);
}
#endif