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-rw-r--r--include/exec/memory.h5
-rw-r--r--include/fpu/softfloat.h84
-rw-r--r--include/qemu/atomic.h61
-rw-r--r--include/qemu/queue.h13
-rw-r--r--include/qemu/rcu.h147
-rw-r--r--include/qemu/thread.h3
-rw-r--r--include/qemu/timer.h1
7 files changed, 290 insertions, 24 deletions
diff --git a/include/exec/memory.h b/include/exec/memory.h
index 0cd96b152e..06ffa1d185 100644
--- a/include/exec/memory.h
+++ b/include/exec/memory.h
@@ -33,6 +33,7 @@
 #include "qemu/notify.h"
 #include "qapi/error.h"
 #include "qom/object.h"
+#include "qemu/rcu.h"
 
 #define MAX_PHYS_ADDR_SPACE_BITS 62
 #define MAX_PHYS_ADDR            (((hwaddr)1 << MAX_PHYS_ADDR_SPACE_BITS) - 1)
@@ -207,9 +208,13 @@ struct MemoryListener {
  */
 struct AddressSpace {
     /* All fields are private. */
+    struct rcu_head rcu;
     char *name;
     MemoryRegion *root;
+
+    /* Accessed via RCU.  */
     struct FlatView *current_map;
+
     int ioeventfd_nb;
     struct MemoryRegionIoeventfd *ioeventfds;
     struct AddressSpaceDispatch *dispatch;
diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h
index e32e25d547..35019c9bf3 100644
--- a/include/fpu/softfloat.h
+++ b/include/fpu/softfloat.h
@@ -1,13 +1,24 @@
 /*
  * QEMU float support
  *
- * Derived from SoftFloat.
+ * The code in this source file is derived from release 2a of the SoftFloat
+ * IEC/IEEE Floating-point Arithmetic Package. Those parts of the code (and
+ * some later contributions) are provided under that license, as detailed below.
+ * It has subsequently been modified by contributors to the QEMU Project,
+ * so some portions are provided under:
+ *  the SoftFloat-2a license
+ *  the BSD license
+ *  GPL-v2-or-later
+ *
+ * Any future contributions to this file after December 1st 2014 will be
+ * taken to be licensed under the Softfloat-2a license unless specifically
+ * indicated otherwise.
  */
 
-/*============================================================================
-
-This C header file is part of the SoftFloat IEC/IEEE Floating-point Arithmetic
-Package, Release 2b.
+/*
+===============================================================================
+This C header file is part of the SoftFloat IEC/IEEE Floating-point
+Arithmetic Package, Release 2a.
 
 Written by John R. Hauser.  This work was made possible in part by the
 International Computer Science Institute, located at Suite 600, 1947 Center
@@ -16,24 +27,57 @@ National Science Foundation under grant MIP-9311980.  The original version
 of this code was written as part of a project to build a fixed-point vector
 processor in collaboration with the University of California at Berkeley,
 overseen by Profs. Nelson Morgan and John Wawrzynek.  More information
-is available through the Web page `http://www.cs.berkeley.edu/~jhauser/
+is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
 arithmetic/SoftFloat.html'.
 
-THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort has
-been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT TIMES
-RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO PERSONS
-AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ALL LOSSES,
-COSTS, OR OTHER PROBLEMS THEY INCUR DUE TO THE SOFTWARE, AND WHO FURTHERMORE
-EFFECTIVELY INDEMNIFY JOHN HAUSER AND THE INTERNATIONAL COMPUTER SCIENCE
-INSTITUTE (possibly via similar legal warning) AGAINST ALL LOSSES, COSTS, OR
-OTHER PROBLEMS INCURRED BY THEIR CUSTOMERS AND CLIENTS DUE TO THE SOFTWARE.
+THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort
+has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
+TIMES RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO
+PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
+AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
 
 Derivative works are acceptable, even for commercial purposes, so long as
-(1) the source code for the derivative work includes prominent notice that
-the work is derivative, and (2) the source code includes prominent notice with
-these four paragraphs for those parts of this code that are retained.
+(1) they include prominent notice that the work is derivative, and (2) they
+include prominent notice akin to these four paragraphs for those parts of
+this code that are retained.
+
+===============================================================================
+*/
+
+/* BSD licensing:
+ * Copyright (c) 2006, Fabrice Bellard
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of the copyright holder nor the names of its contributors
+ * may be used to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
+ * THE POSSIBILITY OF SUCH DAMAGE.
+ */
 
-=============================================================================*/
+/* Portions of this work are licensed under the terms of the GNU GPL,
+ * version 2 or later. See the COPYING file in the top-level directory.
+ */
 
 #ifndef SOFTFLOAT_H
 #define SOFTFLOAT_H
@@ -275,11 +319,11 @@ float64 uint32_to_float64(uint32_t STATUS_PARAM);
 floatx80 int32_to_floatx80(int32_t STATUS_PARAM);
 float128 int32_to_float128(int32_t STATUS_PARAM);
 float32 int64_to_float32(int64_t STATUS_PARAM);
-float32 uint64_to_float32(uint64_t STATUS_PARAM);
 float64 int64_to_float64(int64_t STATUS_PARAM);
-float64 uint64_to_float64(uint64_t STATUS_PARAM);
 floatx80 int64_to_floatx80(int64_t STATUS_PARAM);
 float128 int64_to_float128(int64_t STATUS_PARAM);
+float32 uint64_to_float32(uint64_t STATUS_PARAM);
+float64 uint64_to_float64(uint64_t STATUS_PARAM);
 float128 uint64_to_float128(uint64_t STATUS_PARAM);
 
 /* We provide the int16 versions for symmetry of API with float-to-int */
diff --git a/include/qemu/atomic.h b/include/qemu/atomic.h
index 93c2ae2f37..98e05ca875 100644
--- a/include/qemu/atomic.h
+++ b/include/qemu/atomic.h
@@ -129,6 +129,67 @@
 #define atomic_set(ptr, i)     ((*(__typeof__(*ptr) volatile*) (ptr)) = (i))
 #endif
 
+/**
+ * atomic_rcu_read - reads a RCU-protected pointer to a local variable
+ * into a RCU read-side critical section. The pointer can later be safely
+ * dereferenced within the critical section.
+ *
+ * This ensures that the pointer copy is invariant thorough the whole critical
+ * section.
+ *
+ * Inserts memory barriers on architectures that require them (currently only
+ * Alpha) and documents which pointers are protected by RCU.
+ *
+ * Unless the __ATOMIC_CONSUME memory order is available, atomic_rcu_read also
+ * includes a compiler barrier to ensure that value-speculative optimizations
+ * (e.g. VSS: Value Speculation Scheduling) does not perform the data read
+ * before the pointer read by speculating the value of the pointer.  On new
+ * enough compilers, atomic_load takes care of such concern about
+ * dependency-breaking optimizations.
+ *
+ * Should match atomic_rcu_set(), atomic_xchg(), atomic_cmpxchg().
+ */
+#ifndef atomic_rcu_read
+#ifdef __ATOMIC_CONSUME
+#define atomic_rcu_read(ptr)    ({                \
+    typeof(*ptr) _val;                            \
+     __atomic_load(ptr, &_val, __ATOMIC_CONSUME); \
+    _val;                                         \
+})
+#else
+#define atomic_rcu_read(ptr)    ({                \
+    typeof(*ptr) _val = atomic_read(ptr);         \
+    smp_read_barrier_depends();                   \
+    _val;                                         \
+})
+#endif
+#endif
+
+/**
+ * atomic_rcu_set - assigns (publicizes) a pointer to a new data structure
+ * meant to be read by RCU read-side critical sections.
+ *
+ * Documents which pointers will be dereferenced by RCU read-side critical
+ * sections and adds the required memory barriers on architectures requiring
+ * them. It also makes sure the compiler does not reorder code initializing the
+ * data structure before its publication.
+ *
+ * Should match atomic_rcu_read().
+ */
+#ifndef atomic_rcu_set
+#ifdef __ATOMIC_RELEASE
+#define atomic_rcu_set(ptr, i)  do {              \
+    typeof(*ptr) _val = (i);                      \
+    __atomic_store(ptr, &_val, __ATOMIC_RELEASE); \
+} while(0)
+#else
+#define atomic_rcu_set(ptr, i)  do {              \
+    smp_wmb();                                    \
+    atomic_set(ptr, i);                           \
+} while (0)
+#endif
+#endif
+
 /* These have the same semantics as Java volatile variables.
  * See http://gee.cs.oswego.edu/dl/jmm/cookbook.html:
  * "1. Issue a StoreStore barrier (wmb) before each volatile store."
diff --git a/include/qemu/queue.h b/include/qemu/queue.h
index a98eb3ad79..c602797652 100644
--- a/include/qemu/queue.h
+++ b/include/qemu/queue.h
@@ -104,6 +104,19 @@ struct {                                                                \
         (head)->lh_first = NULL;                                        \
 } while (/*CONSTCOND*/0)
 
+#define QLIST_SWAP(dstlist, srclist, field) do {                        \
+        void *tmplist;                                                  \
+        tmplist = (srclist)->lh_first;                                  \
+        (srclist)->lh_first = (dstlist)->lh_first;                      \
+        if ((srclist)->lh_first != NULL) {                              \
+            (srclist)->lh_first->field.le_prev = &(srclist)->lh_first;  \
+        }                                                               \
+        (dstlist)->lh_first = tmplist;                                  \
+        if ((dstlist)->lh_first != NULL) {                              \
+            (dstlist)->lh_first->field.le_prev = &(dstlist)->lh_first;  \
+        }                                                               \
+} while (/*CONSTCOND*/0)
+
 #define QLIST_INSERT_AFTER(listelm, elm, field) do {                    \
         if (((elm)->field.le_next = (listelm)->field.le_next) != NULL)  \
                 (listelm)->field.le_next->field.le_prev =               \
diff --git a/include/qemu/rcu.h b/include/qemu/rcu.h
new file mode 100644
index 0000000000..068a279a79
--- /dev/null
+++ b/include/qemu/rcu.h
@@ -0,0 +1,147 @@
+#ifndef QEMU_RCU_H
+#define QEMU_RCU_H
+
+/*
+ * urcu-mb.h
+ *
+ * Userspace RCU header with explicit memory barrier.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ * IBM's contributions to this file may be relicensed under LGPLv2 or later.
+ */
+
+#include <stdlib.h>
+#include <assert.h>
+#include <limits.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <glib.h>
+
+#include "qemu/compiler.h"
+#include "qemu/thread.h"
+#include "qemu/queue.h"
+#include "qemu/atomic.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*
+ * Important !
+ *
+ * Each thread containing read-side critical sections must be registered
+ * with rcu_register_thread() before calling rcu_read_lock().
+ * rcu_unregister_thread() should be called before the thread exits.
+ */
+
+#ifdef DEBUG_RCU
+#define rcu_assert(args...)    assert(args)
+#else
+#define rcu_assert(args...)
+#endif
+
+/*
+ * Global quiescent period counter with low-order bits unused.
+ * Using a int rather than a char to eliminate false register dependencies
+ * causing stalls on some architectures.
+ */
+extern unsigned long rcu_gp_ctr;
+
+extern QemuEvent rcu_gp_event;
+
+struct rcu_reader_data {
+    /* Data used by both reader and synchronize_rcu() */
+    unsigned long ctr;
+    bool waiting;
+
+    /* Data used by reader only */
+    unsigned depth;
+
+    /* Data used for registry, protected by rcu_gp_lock */
+    QLIST_ENTRY(rcu_reader_data) node;
+};
+
+extern __thread struct rcu_reader_data rcu_reader;
+
+static inline void rcu_read_lock(void)
+{
+    struct rcu_reader_data *p_rcu_reader = &rcu_reader;
+    unsigned ctr;
+
+    if (p_rcu_reader->depth++ > 0) {
+        return;
+    }
+
+    ctr = atomic_read(&rcu_gp_ctr);
+    atomic_xchg(&p_rcu_reader->ctr, ctr);
+    if (atomic_read(&p_rcu_reader->waiting)) {
+        atomic_set(&p_rcu_reader->waiting, false);
+        qemu_event_set(&rcu_gp_event);
+    }
+}
+
+static inline void rcu_read_unlock(void)
+{
+    struct rcu_reader_data *p_rcu_reader = &rcu_reader;
+
+    assert(p_rcu_reader->depth != 0);
+    if (--p_rcu_reader->depth > 0) {
+        return;
+    }
+
+    atomic_xchg(&p_rcu_reader->ctr, 0);
+    if (atomic_read(&p_rcu_reader->waiting)) {
+        atomic_set(&p_rcu_reader->waiting, false);
+        qemu_event_set(&rcu_gp_event);
+    }
+}
+
+extern void synchronize_rcu(void);
+
+/*
+ * Reader thread registration.
+ */
+extern void rcu_register_thread(void);
+extern void rcu_unregister_thread(void);
+
+struct rcu_head;
+typedef void RCUCBFunc(struct rcu_head *head);
+
+struct rcu_head {
+    struct rcu_head *next;
+    RCUCBFunc *func;
+};
+
+extern void call_rcu1(struct rcu_head *head, RCUCBFunc *func);
+
+/* The operands of the minus operator must have the same type,
+ * which must be the one that we specify in the cast.
+ */
+#define call_rcu(head, func, field)                                      \
+    call_rcu1(({                                                         \
+         char __attribute__((unused))                                    \
+            offset_must_be_zero[-offsetof(typeof(*(head)), field)],      \
+            func_type_invalid = (func) - (void (*)(typeof(head)))(func); \
+         &(head)->field;                                                 \
+      }),                                                                \
+      (RCUCBFunc *)(func))
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* QEMU_RCU_H */
diff --git a/include/qemu/thread.h b/include/qemu/thread.h
index e89fdc9785..5114ec8e79 100644
--- a/include/qemu/thread.h
+++ b/include/qemu/thread.h
@@ -25,9 +25,6 @@ void qemu_mutex_lock(QemuMutex *mutex);
 int qemu_mutex_trylock(QemuMutex *mutex);
 void qemu_mutex_unlock(QemuMutex *mutex);
 
-#define rcu_read_lock() do { } while (0)
-#define rcu_read_unlock() do { } while (0)
-
 void qemu_cond_init(QemuCond *cond);
 void qemu_cond_destroy(QemuCond *cond);
 
diff --git a/include/qemu/timer.h b/include/qemu/timer.h
index ca5befba0e..eba8b2109c 100644
--- a/include/qemu/timer.h
+++ b/include/qemu/timer.h
@@ -838,7 +838,6 @@ static inline int64_t get_clock(void)
 int64_t cpu_get_icount_raw(void);
 int64_t cpu_get_icount(void);
 int64_t cpu_get_clock(void);
-int64_t cpu_get_clock_offset(void);
 int64_t cpu_icount_to_ns(int64_t icount);
 
 /*******************************************/