exec: Remove MemoryRegion::global_locking field

Last uses of memory_region_clear_global_locking() have been
removed in commit 7070e085d4 ("acpi: mark PMTIMER as unlocked")
and commit 08565552f7 ("cputlb: Move NOTDIRTY handling from I/O
path to TLB path").
Remove memory_region_clear_global_locking() and the now unused
'global_locking' field in MemoryRegion.

Reported-by: Alexander Bulekov <alxndr@bu.edu>
Suggested-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20200806150726.962-1-philmd@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

4 files changed, 3 insertions, 23 deletions

diff --git a/accel/tcg/cputlb.c b/accel/tcg/cputlb.c
index aaf8e46ae5..2bbbb3ab29 100644
--- a/accel/tcg/cputlb.c
+++ b/accel/tcg/cputlb.c
@@ -1053,7 +1053,7 @@ static uint64_t io_readx(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
         cpu_io_recompile(cpu, retaddr);
     }
 
-    if (mr->global_locking && !qemu_mutex_iothread_locked()) {
+    if (!qemu_mutex_iothread_locked()) {
         qemu_mutex_lock_iothread();
         locked = true;
     }
@@ -1114,7 +1114,7 @@ static void io_writex(CPUArchState *env, CPUIOTLBEntry *iotlbentry,
      */
     save_iotlb_data(cpu, iotlbentry->addr, section, mr_offset);
 
-    if (mr->global_locking && !qemu_mutex_iothread_locked()) {
+    if (!qemu_mutex_iothread_locked()) {
         qemu_mutex_lock_iothread();
         locked = true;
     }
diff --git a/exec.c b/exec.c
index 3f5deb35ff..c088559d94 100644
--- a/exec.c
+++ b/exec.c
@@ -3137,7 +3137,7 @@ static bool prepare_mmio_access(MemoryRegion *mr)
     bool unlocked = !qemu_mutex_iothread_locked();
     bool release_lock = false;
 
-    if (unlocked && mr->global_locking) {
+    if (unlocked) {
         qemu_mutex_lock_iothread();
         unlocked = false;
         release_lock = true;
diff --git a/include/exec/memory.h b/include/exec/memory.h
index e22f5f5bb7..dee0985162 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -404,7 +404,6 @@ struct MemoryRegion {
     bool nonvolatile;
     bool rom_device;
     bool flush_coalesced_mmio;
-    bool global_locking;
     uint8_t dirty_log_mask;
     bool is_iommu;
     RAMBlock *ram_block;
@@ -1739,19 +1738,6 @@ void memory_region_set_flush_coalesced(MemoryRegion *mr);
 void memory_region_clear_flush_coalesced(MemoryRegion *mr);
 
 /**
- * memory_region_clear_global_locking: Declares that access processing does
- *                                     not depend on the QEMU global lock.
- *
- * By clearing this property, accesses to the memory region will be processed
- * outside of QEMU's global lock (unless the lock is held on when issuing the
- * access request). In this case, the device model implementing the access
- * handlers is responsible for synchronization of concurrency.
- *
- * @mr: the memory region to be updated.
- */
-void memory_region_clear_global_locking(MemoryRegion *mr);
-
-/**
  * memory_region_add_eventfd: Request an eventfd to be triggered when a word
  *                            is written to a location.
  *
diff --git a/softmmu/memory.c b/softmmu/memory.c
index da5f90f141..fa280a19f7 100644
--- a/softmmu/memory.c
+++ b/softmmu/memory.c
@@ -1221,7 +1221,6 @@ static void memory_region_initfn(Object *obj)
     mr->ops = &unassigned_mem_ops;
     mr->enabled = true;
     mr->romd_mode = true;
-    mr->global_locking = true;
     mr->destructor = memory_region_destructor_none;
     QTAILQ_INIT(&mr->subregions);
     QTAILQ_INIT(&mr->coalesced);
@@ -2277,11 +2276,6 @@ void memory_region_clear_flush_coalesced(MemoryRegion *mr)
     }
 }
 
-void memory_region_clear_global_locking(MemoryRegion *mr)
-{
-    mr->global_locking = false;
-}
-
 static bool userspace_eventfd_warning;
 
 void memory_region_add_eventfd(MemoryRegion *mr,