From 752f1c1fe9e74ebb0d373276b332b3242e589208 Mon Sep 17 00:00:00 2001
From: Mitch Hayenga <mitch.hayenga@arm.com>
Date: Thu, 21 Jul 2016 17:19:16 +0100
Subject: cpu: Fix Minor SMT WFI/drain interaction issues

The behavior of WFI is to cause minor to cease evaluating
pipeline logic until an interrupt is observed, however
a user may wish to drain the system while a core is sleeping
due to a WFI.  This patch makes WFI drain.  If an actual
drain occurs during a WFI, the CPU is already drained and will
immediately be ready for swapping, checkpointing, etc.  This
should not negatively impact performance as WFI instructions
are 'stream-changing' (treated like unpredicted branches), so
all remaining instructions are wrong-path and will be squashed
rapidly.

Change-Id: I63833d5acb53d8dde78f9f0c9611de0ece385e45
---
 src/cpu/minor/fetch2.cc | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

(limited to 'src/cpu/minor/fetch2.cc')

diff --git a/src/cpu/minor/fetch2.cc b/src/cpu/minor/fetch2.cc
index ae02b1c22..394fe8549 100644
--- a/src/cpu/minor/fetch2.cc
+++ b/src/cpu/minor/fetch2.cc
@@ -563,8 +563,7 @@ Fetch2::getScheduledThread()
     }
 
     for (auto tid : priority_list) {
-        if (cpu.getContext(tid)->status() == ThreadContext::Active &&
-            getInput(tid) && !fetchInfo[tid].blocked) {
+        if (getInput(tid) && !fetchInfo[tid].blocked) {
             threadPriority = tid;
             return tid;
         }
-- 
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