Merge remote-tracking branch 'remotes/rth/tags/pull-atomic-20161026' into staging

cmpxchg emulation of atomics, v8

# gpg: Signature made Wed 26 Oct 2016 16:30:03 BST
# gpg:                using RSA key 0xAD1270CC4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"
# Primary key fingerprint: 9CB1 8DDA F8E8 49AD 2AFC  16A4 AD12 70CC 4DD0 279B

* remotes/rth/tags/pull-atomic-20161026: (37 commits)
  target-alpha: Emulate LL/SC using cmpxchg helpers
  target-alpha: Introduce MMU_PHYS_IDX
  target-arm: remove EXCP_STREX + cpu_exclusive_{test, info}
  linux-user: remove handling of aarch64's EXCP_STREX
  linux-user: remove handling of ARM's EXCP_STREX
  target-arm: emulate aarch64's LL/SC using cmpxchg helpers
  target-arm: emulate SWP with atomic_xchg helper
  target-arm: emulate LL/SC using cmpxchg helpers
  target-arm: Rearrange aa32 load and store functions
  tests: add atomic_add-bench
  target-i386: remove helper_lock()
  target-i386: emulate XCHG using atomic helper
  target-i386: emulate LOCK'ed BTX ops using atomic helpers
  target-i386: emulate LOCK'ed XADD using atomic helper
  target-i386: emulate LOCK'ed NEG using cmpxchg helper
  target-i386: emulate LOCK'ed NOT using atomic helper
  target-i386: emulate LOCK'ed INC using atomic helper
  target-i386: emulate LOCK'ed OP instructions using atomic helpers
  target-i386: emulate LOCK'ed cmpxchg using cmpxchg helpers
  tcg: Emit barriers with parallel_cpus
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

4 files changed, 178 insertions, 12 deletions

diff --git a/tests/.gitignore b/tests/.gitignore
index 4aec8bc5fa..64e050e859 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -1,3 +1,4 @@
+atomic_add-bench
 check-qdict
 check-qfloat
 check-qint
diff --git a/tests/Makefile.include b/tests/Makefile.include
index cd058efc14..22656eaf26 100644
--- a/tests/Makefile.include
+++ b/tests/Makefile.include
@@ -460,7 +460,8 @@ test-obj-y = tests/check-qint.o tests/check-qstring.o tests/check-qdict.o \
 	tests/test-opts-visitor.o tests/test-qmp-event.o \
 	tests/rcutorture.o tests/test-rcu-list.o \
 	tests/test-qdist.o \
-	tests/test-qht.o tests/qht-bench.o tests/test-qht-par.o
+	tests/test-qht.o tests/qht-bench.o tests/test-qht-par.o \
+	tests/atomic_add-bench.o
 
 $(test-obj-y): QEMU_INCLUDES += -Itests
 QEMU_CFLAGS += -I$(SRC_PATH)/tests
@@ -507,6 +508,7 @@ tests/test-qht$(EXESUF): tests/test-qht.o $(test-util-obj-y)
 tests/test-qht-par$(EXESUF): tests/test-qht-par.o tests/qht-bench$(EXESUF) $(test-util-obj-y)
 tests/qht-bench$(EXESUF): tests/qht-bench.o $(test-util-obj-y)
 tests/test-bufferiszero$(EXESUF): tests/test-bufferiszero.o $(test-util-obj-y)
+tests/atomic_add-bench$(EXESUF): tests/atomic_add-bench.o $(test-util-obj-y)
 
 tests/test-qdev-global-props$(EXESUF): tests/test-qdev-global-props.o \
 	hw/core/qdev.o hw/core/qdev-properties.o hw/core/hotplug.o\
diff --git a/tests/atomic_add-bench.c b/tests/atomic_add-bench.c
new file mode 100644
index 0000000000..caa1e8e689
--- /dev/null
+++ b/tests/atomic_add-bench.c
@@ -0,0 +1,163 @@
+#include "qemu/osdep.h"
+#include "qemu/thread.h"
+#include "qemu/host-utils.h"
+#include "qemu/processor.h"
+
+struct thread_info {
+    uint64_t r;
+} QEMU_ALIGNED(64);
+
+struct count {
+    unsigned long val;
+} QEMU_ALIGNED(64);
+
+static QemuThread *threads;
+static struct thread_info *th_info;
+static unsigned int n_threads = 1;
+static unsigned int n_ready_threads;
+static struct count *counts;
+static unsigned int duration = 1;
+static unsigned int range = 1024;
+static bool test_start;
+static bool test_stop;
+
+static const char commands_string[] =
+    " -n = number of threads\n"
+    " -d = duration in seconds\n"
+    " -r = range (will be rounded up to pow2)";
+
+static void usage_complete(char *argv[])
+{
+    fprintf(stderr, "Usage: %s [options]\n", argv[0]);
+    fprintf(stderr, "options:\n%s\n", commands_string);
+}
+
+/*
+ * From: https://en.wikipedia.org/wiki/Xorshift
+ * This is faster than rand_r(), and gives us a wider range (RAND_MAX is only
+ * guaranteed to be >= INT_MAX).
+ */
+static uint64_t xorshift64star(uint64_t x)
+{
+    x ^= x >> 12; /* a */
+    x ^= x << 25; /* b */
+    x ^= x >> 27; /* c */
+    return x * UINT64_C(2685821657736338717);
+}
+
+static void *thread_func(void *arg)
+{
+    struct thread_info *info = arg;
+
+    atomic_inc(&n_ready_threads);
+    while (!atomic_read(&test_start)) {
+        cpu_relax();
+    }
+
+    while (!atomic_read(&test_stop)) {
+        unsigned int index;
+
+        info->r = xorshift64star(info->r);
+        index = info->r & (range - 1);
+        atomic_inc(&counts[index].val);
+    }
+    return NULL;
+}
+
+static void run_test(void)
+{
+    unsigned int remaining;
+    unsigned int i;
+
+    while (atomic_read(&n_ready_threads) != n_threads) {
+        cpu_relax();
+    }
+    atomic_set(&test_start, true);
+    do {
+        remaining = sleep(duration);
+    } while (remaining);
+    atomic_set(&test_stop, true);
+
+    for (i = 0; i < n_threads; i++) {
+        qemu_thread_join(&threads[i]);
+    }
+}
+
+static void create_threads(void)
+{
+    unsigned int i;
+
+    threads = g_new(QemuThread, n_threads);
+    th_info = g_new(struct thread_info, n_threads);
+    counts = qemu_memalign(64, sizeof(*counts) * range);
+    memset(counts, 0, sizeof(*counts) * range);
+
+    for (i = 0; i < n_threads; i++) {
+        struct thread_info *info = &th_info[i];
+
+        info->r = (i + 1) ^ time(NULL);
+        qemu_thread_create(&threads[i], NULL, thread_func, info,
+                           QEMU_THREAD_JOINABLE);
+    }
+}
+
+static void pr_params(void)
+{
+    printf("Parameters:\n");
+    printf(" # of threads:      %u\n", n_threads);
+    printf(" duration:          %u\n", duration);
+    printf(" ops' range:        %u\n", range);
+}
+
+static void pr_stats(void)
+{
+    unsigned long long val = 0;
+    unsigned int i;
+    double tx;
+
+    for (i = 0; i < range; i++) {
+        val += counts[i].val;
+    }
+    tx = val / duration / 1e6;
+
+    printf("Results:\n");
+    printf("Duration:            %u s\n", duration);
+    printf(" Throughput:         %.2f Mops/s\n", tx);
+    printf(" Throughput/thread:  %.2f Mops/s/thread\n", tx / n_threads);
+}
+
+static void parse_args(int argc, char *argv[])
+{
+    int c;
+
+    for (;;) {
+        c = getopt(argc, argv, "hd:n:r:");
+        if (c < 0) {
+            break;
+        }
+        switch (c) {
+        case 'h':
+            usage_complete(argv);
+            exit(0);
+        case 'd':
+            duration = atoi(optarg);
+            break;
+        case 'n':
+            n_threads = atoi(optarg);
+            break;
+        case 'r':
+            range = pow2ceil(atoi(optarg));
+            break;
+        }
+    }
+}
+
+int main(int argc, char *argv[])
+{
+    parse_args(argc, argv);
+    pr_params();
+    create_threads();
+    run_test();
+    pr_stats();
+    return 0;
+}
diff --git a/tests/test-int128.c b/tests/test-int128.c
index 4390123bd3..b86a3c76e6 100644
--- a/tests/test-int128.c
+++ b/tests/test-int128.c
@@ -41,7 +41,7 @@ static Int128 expand(uint32_t x)
     uint64_t l, h;
     l = expand16(x & 65535);
     h = expand16(x >> 16);
-    return (Int128) {l, h};
+    return (Int128) int128_make128(l, h);
 };
 
 static void test_and(void)
@@ -54,8 +54,8 @@ static void test_and(void)
             Int128 b = expand(tests[j]);
             Int128 r = expand(tests[i] & tests[j]);
             Int128 s = int128_and(a, b);
-            g_assert_cmpuint(r.lo, ==, s.lo);
-            g_assert_cmpuint(r.hi, ==, s.hi);
+            g_assert_cmpuint(int128_getlo(r), ==, int128_getlo(s));
+            g_assert_cmpuint(int128_gethi(r), ==, int128_gethi(s));
         }
     }
 }
@@ -70,8 +70,8 @@ static void test_add(void)
             Int128 b = expand(tests[j]);
             Int128 r = expand(tests[i] + tests[j]);
             Int128 s = int128_add(a, b);
-            g_assert_cmpuint(r.lo, ==, s.lo);
-            g_assert_cmpuint(r.hi, ==, s.hi);
+            g_assert_cmpuint(int128_getlo(r), ==, int128_getlo(s));
+            g_assert_cmpuint(int128_gethi(r), ==, int128_gethi(s));
         }
     }
 }
@@ -86,8 +86,8 @@ static void test_sub(void)
             Int128 b = expand(tests[j]);
             Int128 r = expand(tests[i] - tests[j]);
             Int128 s = int128_sub(a, b);
-            g_assert_cmpuint(r.lo, ==, s.lo);
-            g_assert_cmpuint(r.hi, ==, s.hi);
+            g_assert_cmpuint(int128_getlo(r), ==, int128_getlo(s));
+            g_assert_cmpuint(int128_gethi(r), ==, int128_gethi(s));
         }
     }
 }
@@ -100,8 +100,8 @@ static void test_neg(void)
         Int128 a = expand(tests[i]);
         Int128 r = expand(-tests[i]);
         Int128 s = int128_neg(a);
-        g_assert_cmpuint(r.lo, ==, s.lo);
-        g_assert_cmpuint(r.hi, ==, s.hi);
+        g_assert_cmpuint(int128_getlo(r), ==, int128_getlo(s));
+        g_assert_cmpuint(int128_gethi(r), ==, int128_gethi(s));
     }
 }
 
@@ -180,8 +180,8 @@ test_rshift_one(uint32_t x, int n, uint64_t h, uint64_t l)
 {
     Int128 a = expand(x);
     Int128 r = int128_rshift(a, n);
-    g_assert_cmpuint(r.lo, ==, l);
-    g_assert_cmpuint(r.hi, ==, h);
+    g_assert_cmpuint(int128_getlo(r), ==, l);
+    g_assert_cmpuint(int128_gethi(r), ==, h);
 }
 
 static void test_rshift(void)