[Qemu-devel] [PATCH 08/12] target/ppc: Fix synchronization of mttcg with broadcast TLB flushes

["Cédric Le Goater" <clg@kaod.org>]

From: Benjamin Herrenschmidt <benh@kernel.crashing.org>

Let's use the generic helper tlb_flush_all_cpus_synced() instead
of iterating the CPUs ourselves.

We do lose the optimization of clearing the "other" CPUs "need flush"
flags but this shouldn't be a problem in practice.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 target/ppc/helper_regs.h | 27 ++++++++++-----------------
 1 file changed, 10 insertions(+), 17 deletions(-)

diff --git a/target/ppc/helper_regs.h b/target/ppc/helper_regs.h
index 5efd18049e7c..a2205e1044c9 100644
--- a/target/ppc/helper_regs.h
+++ b/target/ppc/helper_regs.h
@@ -174,26 +174,19 @@ static inline int hreg_store_msr(CPUPPCState *env, target_ulong value,
 static inline void check_tlb_flush(CPUPPCState *env, bool global)
 {
     CPUState *cs = CPU(ppc_env_get_cpu(env));
-    if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
-        tlb_flush(cs);
-        env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
-    }
 
-    /* Propagate TLB invalidations to other CPUs when the guest uses broadcast
-     * TLB invalidation instructions.
-     */
+    /* Handle global flushes first */
     if (global && (env->tlb_need_flush & TLB_NEED_GLOBAL_FLUSH)) {
-        CPUState *other_cs;
-        CPU_FOREACH(other_cs) {
-            if (other_cs != cs) {
-                PowerPCCPU *cpu = POWERPC_CPU(other_cs);
-                CPUPPCState *other_env = &cpu->env;
-
-                other_env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
-                tlb_flush(other_cs);
-            }
-        }
         env->tlb_need_flush &= ~TLB_NEED_GLOBAL_FLUSH;
+        env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
+        tlb_flush_all_cpus_synced(cs);
+        return;
+    }
+
+    /* Then handle local ones */
+    if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
+        env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
+        tlb_flush(cs);
     }
 }
 #else
-- 
2.20.1