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authorGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-02-01 20:53:14 (GMT)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2016-02-01 20:53:14 (GMT)
commit6e9131cc43a672003a75483d9b9db5c51015ae5f (patch)
tree23deb539a695272dc9f003b4ab094037ccc10f31 /tools
parentafc5ab096581e1ad6e7e7d1533a6bbb1d2b12455 (diff)
parent36f90b0a2ddd60823fe193a85e60ff1906c2a9b3 (diff)
downloadlinux-6e9131cc43a672003a75483d9b9db5c51015ae5f.tar.xz
Merge 4.5-rc2 into tty-next
We want the tty/serial fixes in here as well to make merges easier. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'tools')
-rw-r--r--tools/perf/Makefile.perf25
-rw-r--r--tools/perf/arch/x86/tests/intel-cqm.c2
-rw-r--r--tools/perf/config/Makefile4
-rw-r--r--tools/perf/tests/make55
-rw-r--r--tools/perf/ui/browsers/annotate.c4
-rw-r--r--tools/perf/util/hist.c2
-rw-r--r--tools/perf/util/session.c2
-rw-r--r--tools/perf/util/stat.c1
-rw-r--r--tools/perf/util/symbol.c2
-rw-r--r--tools/testing/selftests/timers/valid-adjtimex.c139
-rw-r--r--tools/virtio/asm/barrier.h22
-rw-r--r--tools/virtio/linux/compiler.h9
-rw-r--r--tools/virtio/linux/kernel.h1
-rw-r--r--tools/virtio/ringtest/Makefile22
-rw-r--r--tools/virtio/ringtest/README2
-rw-r--r--tools/virtio/ringtest/main.c366
-rw-r--r--tools/virtio/ringtest/main.h119
-rw-r--r--tools/virtio/ringtest/ring.c272
-rwxr-xr-xtools/virtio/ringtest/run-on-all.sh24
-rw-r--r--tools/virtio/ringtest/virtio_ring_0_9.c316
-rw-r--r--tools/virtio/ringtest/virtio_ring_poll.c2
21 files changed, 1359 insertions, 32 deletions
diff --git a/tools/perf/Makefile.perf b/tools/perf/Makefile.perf
index 0a22407..5d34815 100644
--- a/tools/perf/Makefile.perf
+++ b/tools/perf/Makefile.perf
@@ -77,6 +77,9 @@ include config/utilities.mak
# Define NO_AUXTRACE if you do not want AUX area tracing support
#
# Define NO_LIBBPF if you do not want BPF support
+#
+# Define FEATURES_DUMP to provide features detection dump file
+# and bypass the feature detection
# As per kernel Makefile, avoid funny character set dependencies
unexport LC_ALL
@@ -166,6 +169,15 @@ ifeq ($(config),1)
include config/Makefile
endif
+# The FEATURE_DUMP_EXPORT holds location of the actual
+# FEATURE_DUMP file to be used to bypass feature detection
+# (for bpf or any other subproject)
+ifeq ($(FEATURES_DUMP),)
+FEATURE_DUMP_EXPORT := $(realpath $(OUTPUT)FEATURE-DUMP)
+else
+FEATURE_DUMP_EXPORT := $(FEATURES_DUMP)
+endif
+
export prefix bindir sharedir sysconfdir DESTDIR
# sparse is architecture-neutral, which means that we need to tell it
@@ -436,7 +448,7 @@ $(LIBAPI)-clean:
$(Q)$(MAKE) -C $(LIB_DIR) O=$(OUTPUT) clean >/dev/null
$(LIBBPF): fixdep FORCE
- $(Q)$(MAKE) -C $(BPF_DIR) O=$(OUTPUT) $(OUTPUT)libbpf.a FEATURES_DUMP=$(realpath $(OUTPUT)FEATURE-DUMP)
+ $(Q)$(MAKE) -C $(BPF_DIR) O=$(OUTPUT) $(OUTPUT)libbpf.a FEATURES_DUMP=$(FEATURE_DUMP_EXPORT)
$(LIBBPF)-clean:
$(call QUIET_CLEAN, libbpf)
@@ -611,6 +623,17 @@ clean: $(LIBTRACEEVENT)-clean $(LIBAPI)-clean $(LIBBPF)-clean $(LIBSUBCMD)-clean
$(python-clean)
#
+# To provide FEATURE-DUMP into $(FEATURE_DUMP_COPY)
+# file if defined, with no further action.
+feature-dump:
+ifdef FEATURE_DUMP_COPY
+ @cp $(OUTPUT)FEATURE-DUMP $(FEATURE_DUMP_COPY)
+ @echo "FEATURE-DUMP file copied into $(FEATURE_DUMP_COPY)"
+else
+ @echo "FEATURE-DUMP file available in $(OUTPUT)FEATURE-DUMP"
+endif
+
+#
# Trick: if ../../.git does not exist - we are building out of tree for example,
# then force version regeneration:
#
diff --git a/tools/perf/arch/x86/tests/intel-cqm.c b/tools/perf/arch/x86/tests/intel-cqm.c
index 3e89ba8..7f064eb 100644
--- a/tools/perf/arch/x86/tests/intel-cqm.c
+++ b/tools/perf/arch/x86/tests/intel-cqm.c
@@ -17,7 +17,7 @@ static pid_t spawn(void)
if (pid)
return pid;
- while(1);
+ while(1)
sleep(5);
return 0;
}
diff --git a/tools/perf/config/Makefile b/tools/perf/config/Makefile
index e5959c1..511141b 100644
--- a/tools/perf/config/Makefile
+++ b/tools/perf/config/Makefile
@@ -181,7 +181,11 @@ LDFLAGS += -Wl,-z,noexecstack
EXTLIBS = -lpthread -lrt -lm -ldl
+ifeq ($(FEATURES_DUMP),)
include $(srctree)/tools/build/Makefile.feature
+else
+include $(FEATURES_DUMP)
+endif
ifeq ($(feature-stackprotector-all), 1)
CFLAGS += -fstack-protector-all
diff --git a/tools/perf/tests/make b/tools/perf/tests/make
index df38dec..f918015 100644
--- a/tools/perf/tests/make
+++ b/tools/perf/tests/make
@@ -5,7 +5,7 @@ ifeq ($(MAKECMDGOALS),)
# no target specified, trigger the whole suite
all:
@echo "Testing Makefile"; $(MAKE) -sf tests/make MK=Makefile
- @echo "Testing Makefile.perf"; $(MAKE) -sf tests/make MK=Makefile.perf
+ @echo "Testing Makefile.perf"; $(MAKE) -sf tests/make MK=Makefile.perf SET_PARALLEL=1 SET_O=1
else
# run only specific test over 'Makefile'
%:
@@ -13,6 +13,26 @@ else
endif
else
PERF := .
+PERF_O := $(PERF)
+O_OPT :=
+
+ifneq ($(O),)
+ FULL_O := $(shell readlink -f $(O) || echo $(O))
+ PERF_O := $(FULL_O)
+ ifeq ($(SET_O),1)
+ O_OPT := 'O=$(FULL_O)'
+ endif
+ K_O_OPT := 'O=$(FULL_O)'
+endif
+
+PARALLEL_OPT=
+ifeq ($(SET_PARALLEL),1)
+ cores := $(shell (getconf _NPROCESSORS_ONLN || egrep -c '^processor|^CPU[0-9]' /proc/cpuinfo) 2>/dev/null)
+ ifeq ($(cores),0)
+ cores := 1
+ endif
+ PARALLEL_OPT="-j$(cores)"
+endif
# As per kernel Makefile, avoid funny character set dependencies
unexport LC_ALL
@@ -156,11 +176,11 @@ test_make_doc := $(test_ok)
test_make_help_O := $(test_ok)
test_make_doc_O := $(test_ok)
-test_make_python_perf_so := test -f $(PERF)/python/perf.so
+test_make_python_perf_so := test -f $(PERF_O)/python/perf.so
-test_make_perf_o := test -f $(PERF)/perf.o
-test_make_util_map_o := test -f $(PERF)/util/map.o
-test_make_util_pmu_bison_o := test -f $(PERF)/util/pmu-bison.o
+test_make_perf_o := test -f $(PERF_O)/perf.o
+test_make_util_map_o := test -f $(PERF_O)/util/map.o
+test_make_util_pmu_bison_o := test -f $(PERF_O)/util/pmu-bison.o
define test_dest_files
for file in $(1); do \
@@ -227,7 +247,7 @@ test_make_perf_o_O := test -f $$TMP_O/perf.o
test_make_util_map_o_O := test -f $$TMP_O/util/map.o
test_make_util_pmu_bison_o_O := test -f $$TMP_O/util/pmu-bison.o
-test_default = test -x $(PERF)/perf
+test_default = test -x $(PERF_O)/perf
test = $(if $(test_$1),$(test_$1),$(test_default))
test_default_O = test -x $$TMP_O/perf
@@ -247,12 +267,12 @@ endif
MAKEFLAGS := --no-print-directory
-clean := @(cd $(PERF); make -s -f $(MK) clean >/dev/null)
+clean := @(cd $(PERF); make -s -f $(MK) $(O_OPT) clean >/dev/null)
$(run):
$(call clean)
@TMP_DEST=$$(mktemp -d); \
- cmd="cd $(PERF) && make -f $(MK) DESTDIR=$$TMP_DEST $($@)"; \
+ cmd="cd $(PERF) && make -f $(MK) $(PARALLEL_OPT) $(O_OPT) DESTDIR=$$TMP_DEST $($@)"; \
echo "- $@: $$cmd" && echo $$cmd > $@ && \
( eval $$cmd ) >> $@ 2>&1; \
echo " test: $(call test,$@)" >> $@ 2>&1; \
@@ -263,7 +283,7 @@ $(run_O):
$(call clean)
@TMP_O=$$(mktemp -d); \
TMP_DEST=$$(mktemp -d); \
- cmd="cd $(PERF) && make -f $(MK) O=$$TMP_O DESTDIR=$$TMP_DEST $($(patsubst %_O,%,$@))"; \
+ cmd="cd $(PERF) && make -f $(MK) $(PARALLEL_OPT) O=$$TMP_O DESTDIR=$$TMP_DEST $($(patsubst %_O,%,$@))"; \
echo "- $@: $$cmd" && echo $$cmd > $@ && \
( eval $$cmd ) >> $@ 2>&1 && \
echo " test: $(call test_O,$@)" >> $@ 2>&1; \
@@ -276,17 +296,22 @@ tarpkg:
( eval $$cmd ) >> $@ 2>&1 && \
rm -f $@
+KERNEL_O := ../..
+ifneq ($(O),)
+ KERNEL_O := $(O)
+endif
+
make_kernelsrc:
- @echo "- make -C <kernelsrc> tools/perf"
+ @echo "- make -C <kernelsrc> $(PARALLEL_OPT) $(K_O_OPT) tools/perf"
$(call clean); \
- (make -C ../.. tools/perf) > $@ 2>&1 && \
- test -x perf && rm -f $@ || (cat $@ ; false)
+ (make -C ../.. $(PARALLEL_OPT) $(K_O_OPT) tools/perf) > $@ 2>&1 && \
+ test -x $(KERNEL_O)/tools/perf/perf && rm -f $@ || (cat $@ ; false)
make_kernelsrc_tools:
- @echo "- make -C <kernelsrc>/tools perf"
+ @echo "- make -C <kernelsrc>/tools $(PARALLEL_OPT) $(K_O_OPT) perf"
$(call clean); \
- (make -C ../../tools perf) > $@ 2>&1 && \
- test -x perf && rm -f $@ || (cat $@ ; false)
+ (make -C ../../tools $(PARALLEL_OPT) $(K_O_OPT) perf) > $@ 2>&1 && \
+ test -x $(KERNEL_O)/tools/perf/perf && rm -f $@ || (cat $@ ; false)
all: $(run) $(run_O) tarpkg make_kernelsrc make_kernelsrc_tools
@echo OK
diff --git a/tools/perf/ui/browsers/annotate.c b/tools/perf/ui/browsers/annotate.c
index d4d7cc2..718bd46 100644
--- a/tools/perf/ui/browsers/annotate.c
+++ b/tools/perf/ui/browsers/annotate.c
@@ -755,11 +755,11 @@ static int annotate_browser__run(struct annotate_browser *browser,
nd = browser->curr_hot;
break;
case K_UNTAB:
- if (nd != NULL)
+ if (nd != NULL) {
nd = rb_next(nd);
if (nd == NULL)
nd = rb_first(&browser->entries);
- else
+ } else
nd = browser->curr_hot;
break;
case K_F1:
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index c226303..68a7612 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -131,6 +131,8 @@ void hists__calc_col_len(struct hists *hists, struct hist_entry *h)
symlen = unresolved_col_width + 4 + 2;
hists__new_col_len(hists, HISTC_MEM_DADDR_SYMBOL,
symlen);
+ hists__new_col_len(hists, HISTC_MEM_DCACHELINE,
+ symlen);
}
if (h->mem_info->iaddr.sym) {
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index d5636ba..40b7a0d 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -1149,7 +1149,7 @@ static struct machine *machines__find_for_cpumode(struct machines *machines,
machine = machines__find(machines, pid);
if (!machine)
- machine = machines__find(machines, DEFAULT_GUEST_KERNEL_ID);
+ machine = machines__findnew(machines, DEFAULT_GUEST_KERNEL_ID);
return machine;
}
diff --git a/tools/perf/util/stat.c b/tools/perf/util/stat.c
index 2f901d1..2b58edc 100644
--- a/tools/perf/util/stat.c
+++ b/tools/perf/util/stat.c
@@ -310,7 +310,6 @@ int perf_stat_process_counter(struct perf_stat_config *config,
int i, ret;
aggr->val = aggr->ena = aggr->run = 0;
- init_stats(ps->res_stats);
if (counter->per_pkg)
zero_per_pkg(counter);
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 3b2de6e..ab02209 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1466,7 +1466,7 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter)
* Read the build id if possible. This is required for
* DSO_BINARY_TYPE__BUILDID_DEBUGINFO to work
*/
- if (filename__read_build_id(dso->name, build_id, BUILD_ID_SIZE) > 0)
+ if (filename__read_build_id(dso->long_name, build_id, BUILD_ID_SIZE) > 0)
dso__set_build_id(dso, build_id);
/*
diff --git a/tools/testing/selftests/timers/valid-adjtimex.c b/tools/testing/selftests/timers/valid-adjtimex.c
index e86d937..60fe3c5 100644
--- a/tools/testing/selftests/timers/valid-adjtimex.c
+++ b/tools/testing/selftests/timers/valid-adjtimex.c
@@ -45,7 +45,17 @@ static inline int ksft_exit_fail(void)
}
#endif
-#define NSEC_PER_SEC 1000000000L
+#define NSEC_PER_SEC 1000000000LL
+#define USEC_PER_SEC 1000000LL
+
+#define ADJ_SETOFFSET 0x0100
+
+#include <sys/syscall.h>
+static int clock_adjtime(clockid_t id, struct timex *tx)
+{
+ return syscall(__NR_clock_adjtime, id, tx);
+}
+
/* clear NTP time_status & time_state */
int clear_time_state(void)
@@ -193,10 +203,137 @@ out:
}
+int set_offset(long long offset, int use_nano)
+{
+ struct timex tmx = {};
+ int ret;
+
+ tmx.modes = ADJ_SETOFFSET;
+ if (use_nano) {
+ tmx.modes |= ADJ_NANO;
+
+ tmx.time.tv_sec = offset / NSEC_PER_SEC;
+ tmx.time.tv_usec = offset % NSEC_PER_SEC;
+
+ if (offset < 0 && tmx.time.tv_usec) {
+ tmx.time.tv_sec -= 1;
+ tmx.time.tv_usec += NSEC_PER_SEC;
+ }
+ } else {
+ tmx.time.tv_sec = offset / USEC_PER_SEC;
+ tmx.time.tv_usec = offset % USEC_PER_SEC;
+
+ if (offset < 0 && tmx.time.tv_usec) {
+ tmx.time.tv_sec -= 1;
+ tmx.time.tv_usec += USEC_PER_SEC;
+ }
+ }
+
+ ret = clock_adjtime(CLOCK_REALTIME, &tmx);
+ if (ret < 0) {
+ printf("(sec: %ld usec: %ld) ", tmx.time.tv_sec, tmx.time.tv_usec);
+ printf("[FAIL]\n");
+ return -1;
+ }
+ return 0;
+}
+
+int set_bad_offset(long sec, long usec, int use_nano)
+{
+ struct timex tmx = {};
+ int ret;
+
+ tmx.modes = ADJ_SETOFFSET;
+ if (use_nano)
+ tmx.modes |= ADJ_NANO;
+
+ tmx.time.tv_sec = sec;
+ tmx.time.tv_usec = usec;
+ ret = clock_adjtime(CLOCK_REALTIME, &tmx);
+ if (ret >= 0) {
+ printf("Invalid (sec: %ld usec: %ld) did not fail! ", tmx.time.tv_sec, tmx.time.tv_usec);
+ printf("[FAIL]\n");
+ return -1;
+ }
+ return 0;
+}
+
+int validate_set_offset(void)
+{
+ printf("Testing ADJ_SETOFFSET... ");
+
+ /* Test valid values */
+ if (set_offset(NSEC_PER_SEC - 1, 1))
+ return -1;
+
+ if (set_offset(-NSEC_PER_SEC + 1, 1))
+ return -1;
+
+ if (set_offset(-NSEC_PER_SEC - 1, 1))
+ return -1;
+
+ if (set_offset(5 * NSEC_PER_SEC, 1))
+ return -1;
+
+ if (set_offset(-5 * NSEC_PER_SEC, 1))
+ return -1;
+
+ if (set_offset(5 * NSEC_PER_SEC + NSEC_PER_SEC / 2, 1))
+ return -1;
+
+ if (set_offset(-5 * NSEC_PER_SEC - NSEC_PER_SEC / 2, 1))
+ return -1;
+
+ if (set_offset(USEC_PER_SEC - 1, 0))
+ return -1;
+
+ if (set_offset(-USEC_PER_SEC + 1, 0))
+ return -1;
+
+ if (set_offset(-USEC_PER_SEC - 1, 0))
+ return -1;
+
+ if (set_offset(5 * USEC_PER_SEC, 0))
+ return -1;
+
+ if (set_offset(-5 * USEC_PER_SEC, 0))
+ return -1;
+
+ if (set_offset(5 * USEC_PER_SEC + USEC_PER_SEC / 2, 0))
+ return -1;
+
+ if (set_offset(-5 * USEC_PER_SEC - USEC_PER_SEC / 2, 0))
+ return -1;
+
+ /* Test invalid values */
+ if (set_bad_offset(0, -1, 1))
+ return -1;
+ if (set_bad_offset(0, -1, 0))
+ return -1;
+ if (set_bad_offset(0, 2 * NSEC_PER_SEC, 1))
+ return -1;
+ if (set_bad_offset(0, 2 * USEC_PER_SEC, 0))
+ return -1;
+ if (set_bad_offset(0, NSEC_PER_SEC, 1))
+ return -1;
+ if (set_bad_offset(0, USEC_PER_SEC, 0))
+ return -1;
+ if (set_bad_offset(0, -NSEC_PER_SEC, 1))
+ return -1;
+ if (set_bad_offset(0, -USEC_PER_SEC, 0))
+ return -1;
+
+ printf("[OK]\n");
+ return 0;
+}
+
int main(int argc, char **argv)
{
if (validate_freq())
return ksft_exit_fail();
+ if (validate_set_offset())
+ return ksft_exit_fail();
+
return ksft_exit_pass();
}
diff --git a/tools/virtio/asm/barrier.h b/tools/virtio/asm/barrier.h
index 26b7926..ba34f9e 100644
--- a/tools/virtio/asm/barrier.h
+++ b/tools/virtio/asm/barrier.h
@@ -1,15 +1,19 @@
#if defined(__i386__) || defined(__x86_64__)
#define barrier() asm volatile("" ::: "memory")
-#define mb() __sync_synchronize()
-
-#define smp_mb() mb()
-# define dma_rmb() barrier()
-# define dma_wmb() barrier()
-# define smp_rmb() barrier()
-# define smp_wmb() barrier()
+#define virt_mb() __sync_synchronize()
+#define virt_rmb() barrier()
+#define virt_wmb() barrier()
+/* Atomic store should be enough, but gcc generates worse code in that case. */
+#define virt_store_mb(var, value) do { \
+ typeof(var) virt_store_mb_value = (value); \
+ __atomic_exchange(&(var), &virt_store_mb_value, &virt_store_mb_value, \
+ __ATOMIC_SEQ_CST); \
+ barrier(); \
+} while (0);
/* Weak barriers should be used. If not - it's a bug */
-# define rmb() abort()
-# define wmb() abort()
+# define mb() abort()
+# define rmb() abort()
+# define wmb() abort()
#else
#error Please fill in barrier macros
#endif
diff --git a/tools/virtio/linux/compiler.h b/tools/virtio/linux/compiler.h
new file mode 100644
index 0000000..845960e
--- /dev/null
+++ b/tools/virtio/linux/compiler.h
@@ -0,0 +1,9 @@
+#ifndef LINUX_COMPILER_H
+#define LINUX_COMPILER_H
+
+#define WRITE_ONCE(var, val) \
+ (*((volatile typeof(val) *)(&(var))) = (val))
+
+#define READ_ONCE(var) (*((volatile typeof(val) *)(&(var))))
+
+#endif
diff --git a/tools/virtio/linux/kernel.h b/tools/virtio/linux/kernel.h
index 4db7d56..0338499 100644
--- a/tools/virtio/linux/kernel.h
+++ b/tools/virtio/linux/kernel.h
@@ -8,6 +8,7 @@
#include <assert.h>
#include <stdarg.h>
+#include <linux/compiler.h>
#include <linux/types.h>
#include <linux/printk.h>
#include <linux/bug.h>
diff --git a/tools/virtio/ringtest/Makefile b/tools/virtio/ringtest/Makefile
new file mode 100644
index 0000000..feaa64a
--- /dev/null
+++ b/tools/virtio/ringtest/Makefile
@@ -0,0 +1,22 @@
+all:
+
+all: ring virtio_ring_0_9 virtio_ring_poll
+
+CFLAGS += -Wall
+CFLAGS += -pthread -O2 -ggdb
+LDFLAGS += -pthread -O2 -ggdb
+
+main.o: main.c main.h
+ring.o: ring.c main.h
+virtio_ring_0_9.o: virtio_ring_0_9.c main.h
+virtio_ring_poll.o: virtio_ring_poll.c virtio_ring_0_9.c main.h
+ring: ring.o main.o
+virtio_ring_0_9: virtio_ring_0_9.o main.o
+virtio_ring_poll: virtio_ring_poll.o main.o
+clean:
+ -rm main.o
+ -rm ring.o ring
+ -rm virtio_ring_0_9.o virtio_ring_0_9
+ -rm virtio_ring_poll.o virtio_ring_poll
+
+.PHONY: all clean
diff --git a/tools/virtio/ringtest/README b/tools/virtio/ringtest/README
new file mode 100644
index 0000000..34e94c4
--- /dev/null
+++ b/tools/virtio/ringtest/README
@@ -0,0 +1,2 @@
+Partial implementation of various ring layouts, useful to tune virtio design.
+Uses shared memory heavily.
diff --git a/tools/virtio/ringtest/main.c b/tools/virtio/ringtest/main.c
new file mode 100644
index 0000000..3a5ff43
--- /dev/null
+++ b/tools/virtio/ringtest/main.c
@@ -0,0 +1,366 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * Command line processing and common functions for ring benchmarking.
+ */
+#define _GNU_SOURCE
+#include <getopt.h>
+#include <pthread.h>
+#include <assert.h>
+#include <sched.h>
+#include "main.h"
+#include <sys/eventfd.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <limits.h>
+
+int runcycles = 10000000;
+int max_outstanding = INT_MAX;
+int batch = 1;
+
+bool do_sleep = false;
+bool do_relax = false;
+bool do_exit = true;
+
+unsigned ring_size = 256;
+
+static int kickfd = -1;
+static int callfd = -1;
+
+void notify(int fd)
+{
+ unsigned long long v = 1;
+ int r;
+
+ vmexit();
+ r = write(fd, &v, sizeof v);
+ assert(r == sizeof v);
+ vmentry();
+}
+
+void wait_for_notify(int fd)
+{
+ unsigned long long v = 1;
+ int r;
+
+ vmexit();
+ r = read(fd, &v, sizeof v);
+ assert(r == sizeof v);
+ vmentry();
+}
+
+void kick(void)
+{
+ notify(kickfd);
+}
+
+void wait_for_kick(void)
+{
+ wait_for_notify(kickfd);
+}
+
+void call(void)
+{
+ notify(callfd);
+}
+
+void wait_for_call(void)
+{
+ wait_for_notify(callfd);
+}
+
+void set_affinity(const char *arg)
+{
+ cpu_set_t cpuset;
+ int ret;
+ pthread_t self;
+ long int cpu;
+ char *endptr;
+
+ if (!arg)
+ return;
+
+ cpu = strtol(arg, &endptr, 0);
+ assert(!*endptr);
+
+ assert(cpu >= 0 || cpu < CPU_SETSIZE);
+
+ self = pthread_self();
+ CPU_ZERO(&cpuset);
+ CPU_SET(cpu, &cpuset);
+
+ ret = pthread_setaffinity_np(self, sizeof(cpu_set_t), &cpuset);
+ assert(!ret);
+}
+
+static void run_guest(void)
+{
+ int completed_before;
+ int completed = 0;
+ int started = 0;
+ int bufs = runcycles;
+ int spurious = 0;
+ int r;
+ unsigned len;
+ void *buf;
+ int tokick = batch;
+
+ for (;;) {
+ if (do_sleep)
+ disable_call();
+ completed_before = completed;
+ do {
+ if (started < bufs &&
+ started - completed < max_outstanding) {
+ r = add_inbuf(0, NULL, "Hello, world!");
+ if (__builtin_expect(r == 0, true)) {
+ ++started;
+ if (!--tokick) {
+ tokick = batch;
+ if (do_sleep)
+ kick_available();
+ }
+
+ }
+ } else
+ r = -1;
+
+ /* Flush out completed bufs if any */
+ if (get_buf(&len, &buf)) {
+ ++completed;
+ if (__builtin_expect(completed == bufs, false))
+ return;
+ r = 0;
+ }
+ } while (r == 0);
+ if (completed == completed_before)
+ ++spurious;
+ assert(completed <= bufs);
+ assert(started <= bufs);
+ if (do_sleep) {
+ if (enable_call())
+ wait_for_call();
+ } else {
+ poll_used();
+ }
+ }
+}
+
+static void run_host(void)
+{
+ int completed_before;
+ int completed = 0;
+ int spurious = 0;
+ int bufs = runcycles;
+ unsigned len;
+ void *buf;
+
+ for (;;) {
+ if (do_sleep) {
+ if (enable_kick())
+ wait_for_kick();
+ } else {
+ poll_avail();
+ }
+ if (do_sleep)
+ disable_kick();
+ completed_before = completed;
+ while (__builtin_expect(use_buf(&len, &buf), true)) {
+ if (do_sleep)
+ call_used();
+ ++completed;
+ if (__builtin_expect(completed == bufs, false))
+ return;
+ }
+ if (completed == completed_before)
+ ++spurious;
+ assert(completed <= bufs);
+ if (completed == bufs)
+ break;
+ }
+}
+
+void *start_guest(void *arg)
+{
+ set_affinity(arg);
+ run_guest();
+ pthread_exit(NULL);
+}
+
+void *start_host(void *arg)
+{
+ set_affinity(arg);
+ run_host();
+ pthread_exit(NULL);
+}
+
+static const char optstring[] = "";
+static const struct option longopts[] = {
+ {
+ .name = "help",
+ .has_arg = no_argument,
+ .val = 'h',
+ },
+ {
+ .name = "host-affinity",
+ .has_arg = required_argument,
+ .val = 'H',
+ },
+ {
+ .name = "guest-affinity",
+ .has_arg = required_argument,
+ .val = 'G',
+ },
+ {
+ .name = "ring-size",
+ .has_arg = required_argument,
+ .val = 'R',
+ },
+ {
+ .name = "run-cycles",
+ .has_arg = required_argument,
+ .val = 'C',
+ },
+ {
+ .name = "outstanding",
+ .has_arg = required_argument,
+ .val = 'o',
+ },
+ {
+ .name = "batch",
+ .has_arg = required_argument,
+ .val = 'b',
+ },
+ {
+ .name = "sleep",
+ .has_arg = no_argument,
+ .val = 's',
+ },
+ {
+ .name = "relax",
+ .has_arg = no_argument,
+ .val = 'x',
+ },
+ {
+ .name = "exit",
+ .has_arg = no_argument,
+ .val = 'e',
+ },
+ {
+ }
+};
+
+static void help(void)
+{
+ fprintf(stderr, "Usage: <test> [--help]"
+ " [--host-affinity H]"
+ " [--guest-affinity G]"
+ " [--ring-size R (default: %d)]"
+ " [--run-cycles C (default: %d)]"
+ " [--batch b]"
+ " [--outstanding o]"
+ " [--sleep]"
+ " [--relax]"
+ " [--exit]"
+ "\n",
+ ring_size,
+ runcycles);
+}
+
+int main(int argc, char **argv)
+{
+ int ret;
+ pthread_t host, guest;
+ void *tret;
+ char *host_arg = NULL;
+ char *guest_arg = NULL;
+ char *endptr;
+ long int c;
+
+ kickfd = eventfd(0, 0);
+ assert(kickfd >= 0);
+ callfd = eventfd(0, 0);
+ assert(callfd >= 0);
+
+ for (;;) {
+ int o = getopt_long(argc, argv, optstring, longopts, NULL);
+ switch (o) {
+ case -1:
+ goto done;
+ case '?':
+ help();
+ exit(2);
+ case 'H':
+ host_arg = optarg;
+ break;
+ case 'G':
+ guest_arg = optarg;
+ break;
+ case 'R':
+ ring_size = strtol(optarg, &endptr, 0);
+ assert(ring_size && !(ring_size & (ring_size - 1)));
+ assert(!*endptr);
+ break;
+ case 'C':
+ c = strtol(optarg, &endptr, 0);
+ assert(!*endptr);
+ assert(c > 0 && c < INT_MAX);
+ runcycles = c;
+ break;
+ case 'o':
+ c = strtol(optarg, &endptr, 0);
+ assert(!*endptr);
+ assert(c > 0 && c < INT_MAX);
+ max_outstanding = c;
+ break;
+ case 'b':
+ c = strtol(optarg, &endptr, 0);
+ assert(!*endptr);
+ assert(c > 0 && c < INT_MAX);
+ batch = c;
+ break;
+ case 's':
+ do_sleep = true;
+ break;
+ case 'x':
+ do_relax = true;
+ break;
+ case 'e':
+ do_exit = true;
+ break;
+ default:
+ help();
+ exit(4);
+ break;
+ }
+ }
+
+ /* does nothing here, used to make sure all smp APIs compile */
+ smp_acquire();
+ smp_release();
+ smp_mb();
+done:
+
+ if (batch > max_outstanding)
+ batch = max_outstanding;
+
+ if (optind < argc) {
+ help();
+ exit(4);
+ }
+ alloc_ring();
+
+ ret = pthread_create(&host, NULL, start_host, host_arg);
+ assert(!ret);
+ ret = pthread_create(&guest, NULL, start_guest, guest_arg);
+ assert(!ret);
+
+ ret = pthread_join(guest, &tret);
+ assert(!ret);
+ ret = pthread_join(host, &tret);
+ assert(!ret);
+ return 0;
+}
diff --git a/tools/virtio/ringtest/main.h b/tools/virtio/ringtest/main.h
new file mode 100644
index 0000000..16917ac
--- /dev/null
+++ b/tools/virtio/ringtest/main.h
@@ -0,0 +1,119 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * Common macros and functions for ring benchmarking.
+ */
+#ifndef MAIN_H
+#define MAIN_H
+
+#include <stdbool.h>
+
+extern bool do_exit;
+
+#if defined(__x86_64__) || defined(__i386__)
+#include "x86intrin.h"
+
+static inline void wait_cycles(unsigned long long cycles)
+{
+ unsigned long long t;
+
+ t = __rdtsc();
+ while (__rdtsc() - t < cycles) {}
+}
+
+#define VMEXIT_CYCLES 500
+#define VMENTRY_CYCLES 500
+
+#else
+static inline void wait_cycles(unsigned long long cycles)
+{
+ _Exit(5);
+}
+#define VMEXIT_CYCLES 0
+#define VMENTRY_CYCLES 0
+#endif
+
+static inline void vmexit(void)
+{
+ if (!do_exit)
+ return;
+
+ wait_cycles(VMEXIT_CYCLES);
+}
+static inline void vmentry(void)
+{
+ if (!do_exit)
+ return;
+
+ wait_cycles(VMENTRY_CYCLES);
+}
+
+/* implemented by ring */
+void alloc_ring(void);
+/* guest side */
+int add_inbuf(unsigned, void *, void *);
+void *get_buf(unsigned *, void **);
+void disable_call();
+bool enable_call();
+void kick_available();
+void poll_used();
+/* host side */
+void disable_kick();
+bool enable_kick();
+bool use_buf(unsigned *, void **);
+void call_used();
+void poll_avail();
+
+/* implemented by main */
+extern bool do_sleep;
+void kick(void);
+void wait_for_kick(void);
+void call(void);
+void wait_for_call(void);
+
+extern unsigned ring_size;
+
+/* Compiler barrier - similar to what Linux uses */
+#define barrier() asm volatile("" ::: "memory")
+
+/* Is there a portable way to do this? */
+#if defined(__x86_64__) || defined(__i386__)
+#define cpu_relax() asm ("rep; nop" ::: "memory")
+#else
+#define cpu_relax() assert(0)
+#endif
+
+extern bool do_relax;
+
+static inline void busy_wait(void)
+{
+ if (do_relax)
+ cpu_relax();
+ else
+ /* prevent compiler from removing busy loops */
+ barrier();
+}
+
+/*
+ * Not using __ATOMIC_SEQ_CST since gcc docs say they are only synchronized
+ * with other __ATOMIC_SEQ_CST calls.
+ */
+#define smp_mb() __sync_synchronize()
+
+/*
+ * This abuses the atomic builtins for thread fences, and
+ * adds a compiler barrier.
+ */
+#define smp_release() do { \
+ barrier(); \
+ __atomic_thread_fence(__ATOMIC_RELEASE); \
+} while (0)
+
+#define smp_acquire() do { \
+ __atomic_thread_fence(__ATOMIC_ACQUIRE); \
+ barrier(); \
+} while (0)
+
+#endif
diff --git a/tools/virtio/ringtest/ring.c b/tools/virtio/ringtest/ring.c
new file mode 100644
index 0000000..c25c8d2
--- /dev/null
+++ b/tools/virtio/ringtest/ring.c
@@ -0,0 +1,272 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * Simple descriptor-based ring. virtio 0.9 compatible event index is used for
+ * signalling, unconditionally.
+ */
+#define _GNU_SOURCE
+#include "main.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+/* Next - Where next entry will be written.
+ * Prev - "Next" value when event triggered previously.
+ * Event - Peer requested event after writing this entry.
+ */
+static inline bool need_event(unsigned short event,
+ unsigned short next,
+ unsigned short prev)
+{
+ return (unsigned short)(next - event - 1) < (unsigned short)(next - prev);
+}
+
+/* Design:
+ * Guest adds descriptors with unique index values and DESC_HW in flags.
+ * Host overwrites used descriptors with correct len, index, and DESC_HW clear.
+ * Flags are always set last.
+ */
+#define DESC_HW 0x1
+
+struct desc {
+ unsigned short flags;
+ unsigned short index;
+ unsigned len;
+ unsigned long long addr;
+};
+
+/* how much padding is needed to avoid false cache sharing */
+#define HOST_GUEST_PADDING 0x80
+
+/* Mostly read */
+struct event {
+ unsigned short kick_index;
+ unsigned char reserved0[HOST_GUEST_PADDING - 2];
+ unsigned short call_index;
+ unsigned char reserved1[HOST_GUEST_PADDING - 2];
+};
+
+struct data {
+ void *buf; /* descriptor is writeable, we can't get buf from there */
+ void *data;
+} *data;
+
+struct desc *ring;
+struct event *event;
+
+struct guest {
+ unsigned avail_idx;
+ unsigned last_used_idx;
+ unsigned num_free;
+ unsigned kicked_avail_idx;
+ unsigned char reserved[HOST_GUEST_PADDING - 12];
+} guest;
+
+struct host {
+ /* we do not need to track last avail index
+ * unless we have more than one in flight.
+ */
+ unsigned used_idx;
+ unsigned called_used_idx;
+ unsigned char reserved[HOST_GUEST_PADDING - 4];
+} host;
+
+/* implemented by ring */
+void alloc_ring(void)
+{
+ int ret;
+ int i;
+
+ ret = posix_memalign((void **)&ring, 0x1000, ring_size * sizeof *ring);
+ if (ret) {
+ perror("Unable to allocate ring buffer.\n");
+ exit(3);
+ }
+ event = malloc(sizeof *event);
+ if (!event) {
+ perror("Unable to allocate event buffer.\n");
+ exit(3);
+ }
+ memset(event, 0, sizeof *event);
+ guest.avail_idx = 0;
+ guest.kicked_avail_idx = -1;
+ guest.last_used_idx = 0;
+ host.used_idx = 0;
+ host.called_used_idx = -1;
+ for (i = 0; i < ring_size; ++i) {
+ struct desc desc = {
+ .index = i,
+ };
+ ring[i] = desc;
+ }
+ guest.num_free = ring_size;
+ data = malloc(ring_size * sizeof *data);
+ if (!data) {
+ perror("Unable to allocate data buffer.\n");
+ exit(3);
+ }
+ memset(data, 0, ring_size * sizeof *data);
+}
+
+/* guest side */
+int add_inbuf(unsigned len, void *buf, void *datap)
+{
+ unsigned head, index;
+
+ if (!guest.num_free)
+ return -1;
+
+ guest.num_free--;
+ head = (ring_size - 1) & (guest.avail_idx++);
+
+ /* Start with a write. On MESI architectures this helps
+ * avoid a shared state with consumer that is polling this descriptor.
+ */
+ ring[head].addr = (unsigned long)(void*)buf;
+ ring[head].len = len;
+ /* read below might bypass write above. That is OK because it's just an
+ * optimization. If this happens, we will get the cache line in a
+ * shared state which is unfortunate, but probably not worth it to
+ * add an explicit full barrier to avoid this.
+ */
+ barrier();
+ index = ring[head].index;
+ data[index].buf = buf;
+ data[index].data = datap;
+ /* Barrier A (for pairing) */
+ smp_release();
+ ring[head].flags = DESC_HW;
+
+ return 0;
+}
+
+void *get_buf(unsigned *lenp, void **bufp)
+{
+ unsigned head = (ring_size - 1) & guest.last_used_idx;
+ unsigned index;
+ void *datap;
+
+ if (ring[head].flags & DESC_HW)
+ return NULL;
+ /* Barrier B (for pairing) */
+ smp_acquire();
+ *lenp = ring[head].len;
+ index = ring[head].index & (ring_size - 1);
+ datap = data[index].data;
+ *bufp = data[index].buf;
+ data[index].buf = NULL;
+ data[index].data = NULL;
+ guest.num_free++;
+ guest.last_used_idx++;
+ return datap;
+}
+
+void poll_used(void)
+{
+ unsigned head = (ring_size - 1) & guest.last_used_idx;
+
+ while (ring[head].flags & DESC_HW)
+ busy_wait();
+}
+
+void disable_call()
+{
+ /* Doing nothing to disable calls might cause
+ * extra interrupts, but reduces the number of cache misses.
+ */
+}
+
+bool enable_call()
+{
+ unsigned head = (ring_size - 1) & guest.last_used_idx;
+
+ event->call_index = guest.last_used_idx;
+ /* Flush call index write */
+ /* Barrier D (for pairing) */
+ smp_mb();
+ return ring[head].flags & DESC_HW;
+}
+
+void kick_available(void)
+{
+ /* Flush in previous flags write */
+ /* Barrier C (for pairing) */
+ smp_mb();
+ if (!need_event(event->kick_index,
+ guest.avail_idx,
+ guest.kicked_avail_idx))
+ return;
+
+ guest.kicked_avail_idx = guest.avail_idx;
+ kick();
+}
+
+/* host side */
+void disable_kick()
+{
+ /* Doing nothing to disable kicks might cause
+ * extra interrupts, but reduces the number of cache misses.
+ */
+}
+
+bool enable_kick()
+{
+ unsigned head = (ring_size - 1) & host.used_idx;
+
+ event->kick_index = host.used_idx;
+ /* Barrier C (for pairing) */
+ smp_mb();
+ return !(ring[head].flags & DESC_HW);
+}
+
+void poll_avail(void)
+{
+ unsigned head = (ring_size - 1) & host.used_idx;
+
+ while (!(ring[head].flags & DESC_HW))
+ busy_wait();
+}
+
+bool use_buf(unsigned *lenp, void **bufp)
+{
+ unsigned head = (ring_size - 1) & host.used_idx;
+
+ if (!(ring[head].flags & DESC_HW))
+ return false;
+
+ /* make sure length read below is not speculated */
+ /* Barrier A (for pairing) */
+ smp_acquire();
+
+ /* simple in-order completion: we don't need
+ * to touch index at all. This also means we
+ * can just modify the descriptor in-place.
+ */
+ ring[head].len--;
+ /* Make sure len is valid before flags.
+ * Note: alternative is to write len and flags in one access -
+ * possible on 64 bit architectures but wmb is free on Intel anyway
+ * so I have no way to test whether it's a gain.
+ */
+ /* Barrier B (for pairing) */
+ smp_release();
+ ring[head].flags = 0;
+ host.used_idx++;
+ return true;
+}
+
+void call_used(void)
+{
+ /* Flush in previous flags write */
+ /* Barrier D (for pairing) */
+ smp_mb();
+ if (!need_event(event->call_index,
+ host.used_idx,
+ host.called_used_idx))
+ return;
+
+ host.called_used_idx = host.used_idx;
+ call();
+}
diff --git a/tools/virtio/ringtest/run-on-all.sh b/tools/virtio/ringtest/run-on-all.sh
new file mode 100755
index 0000000..52b0f71
--- /dev/null
+++ b/tools/virtio/ringtest/run-on-all.sh
@@ -0,0 +1,24 @@
+#!/bin/sh
+
+#use last CPU for host. Why not the first?
+#many devices tend to use cpu0 by default so
+#it tends to be busier
+HOST_AFFINITY=$(cd /dev/cpu; ls|grep -v '[a-z]'|sort -n|tail -1)
+
+#run command on all cpus
+for cpu in $(cd /dev/cpu; ls|grep -v '[a-z]'|sort -n);
+do
+ #Don't run guest and host on same CPU
+ #It actually works ok if using signalling
+ if
+ (echo "$@" | grep -e "--sleep" > /dev/null) || \
+ test $HOST_AFFINITY '!=' $cpu
+ then
+ echo "GUEST AFFINITY $cpu"
+ "$@" --host-affinity $HOST_AFFINITY --guest-affinity $cpu
+ fi
+done
+echo "NO GUEST AFFINITY"
+"$@" --host-affinity $HOST_AFFINITY
+echo "NO AFFINITY"
+"$@"
diff --git a/tools/virtio/ringtest/virtio_ring_0_9.c b/tools/virtio/ringtest/virtio_ring_0_9.c
new file mode 100644
index 0000000..47c9a1a
--- /dev/null
+++ b/tools/virtio/ringtest/virtio_ring_0_9.c
@@ -0,0 +1,316 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ * Author: Michael S. Tsirkin <mst@redhat.com>
+ * This work is licensed under the terms of the GNU GPL, version 2.
+ *
+ * Partial implementation of virtio 0.9. event index is used for signalling,
+ * unconditionally. Design roughly follows linux kernel implementation in order
+ * to be able to judge its performance.
+ */
+#define _GNU_SOURCE
+#include "main.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <assert.h>
+#include <string.h>
+#include <linux/virtio_ring.h>
+
+struct data {
+ void *data;
+} *data;
+
+struct vring ring;
+
+/* enabling the below activates experimental ring polling code
+ * (which skips index reads on consumer in favor of looking at
+ * high bits of ring id ^ 0x8000).
+ */
+/* #ifdef RING_POLL */
+
+/* how much padding is needed to avoid false cache sharing */
+#define HOST_GUEST_PADDING 0x80
+
+struct guest {
+ unsigned short avail_idx;
+ unsigned short last_used_idx;
+ unsigned short num_free;
+ unsigned short kicked_avail_idx;
+ unsigned short free_head;
+ unsigned char reserved[HOST_GUEST_PADDING - 10];
+} guest;
+
+struct host {
+ /* we do not need to track last avail index
+ * unless we have more than one in flight.
+ */
+ unsigned short used_idx;
+ unsigned short called_used_idx;
+ unsigned char reserved[HOST_GUEST_PADDING - 4];
+} host;
+
+/* implemented by ring */
+void alloc_ring(void)
+{
+ int ret;
+ int i;
+ void *p;
+
+ ret = posix_memalign(&p, 0x1000, vring_size(ring_size, 0x1000));
+ if (ret) {
+ perror("Unable to allocate ring buffer.\n");
+ exit(3);
+ }
+ memset(p, 0, vring_size(ring_size, 0x1000));
+ vring_init(&ring, ring_size, p, 0x1000);
+
+ guest.avail_idx = 0;
+ guest.kicked_avail_idx = -1;
+ guest.last_used_idx = 0;
+ /* Put everything in free lists. */
+ guest.free_head = 0;
+ for (i = 0; i < ring_size - 1; i++)
+ ring.desc[i].next = i + 1;
+ host.used_idx = 0;
+ host.called_used_idx = -1;
+ guest.num_free = ring_size;
+ data = malloc(ring_size * sizeof *data);
+ if (!data) {
+ perror("Unable to allocate data buffer.\n");
+ exit(3);
+ }
+ memset(data, 0, ring_size * sizeof *data);
+}
+
+/* guest side */
+int add_inbuf(unsigned len, void *buf, void *datap)
+{
+ unsigned head, avail;
+ struct vring_desc *desc;
+
+ if (!guest.num_free)
+ return -1;
+
+ head = guest.free_head;
+ guest.num_free--;
+
+ desc = ring.desc;
+ desc[head].flags = VRING_DESC_F_NEXT;
+ desc[head].addr = (unsigned long)(void *)buf;
+ desc[head].len = len;
+ /* We do it like this to simulate the way
+ * we'd have to flip it if we had multiple
+ * descriptors.
+ */
+ desc[head].flags &= ~VRING_DESC_F_NEXT;
+ guest.free_head = desc[head].next;
+
+ data[head].data = datap;
+
+#ifdef RING_POLL
+ /* Barrier A (for pairing) */
+ smp_release();
+ avail = guest.avail_idx++;
+ ring.avail->ring[avail & (ring_size - 1)] =
+ (head | (avail & ~(ring_size - 1))) ^ 0x8000;
+#else
+ avail = (ring_size - 1) & (guest.avail_idx++);
+ ring.avail->ring[avail] = head;
+ /* Barrier A (for pairing) */
+ smp_release();
+#endif
+ ring.avail->idx = guest.avail_idx;
+ return 0;
+}
+
+void *get_buf(unsigned *lenp, void **bufp)
+{
+ unsigned head;
+ unsigned index;
+ void *datap;
+
+#ifdef RING_POLL
+ head = (ring_size - 1) & guest.last_used_idx;
+ index = ring.used->ring[head].id;
+ if ((index ^ guest.last_used_idx ^ 0x8000) & ~(ring_size - 1))
+ return NULL;
+ /* Barrier B (for pairing) */
+ smp_acquire();
+ index &= ring_size - 1;
+#else
+ if (ring.used->idx == guest.last_used_idx)
+ return NULL;
+ /* Barrier B (for pairing) */
+ smp_acquire();
+ head = (ring_size - 1) & guest.last_used_idx;
+ index = ring.used->ring[head].id;
+#endif
+ *lenp = ring.used->ring[head].len;
+ datap = data[index].data;
+ *bufp = (void*)(unsigned long)ring.desc[index].addr;
+ data[index].data = NULL;
+ ring.desc[index].next = guest.free_head;
+ guest.free_head = index;
+ guest.num_free++;
+ guest.last_used_idx++;
+ return datap;
+}
+
+void poll_used(void)
+{
+#ifdef RING_POLL
+ unsigned head = (ring_size - 1) & guest.last_used_idx;
+
+ for (;;) {
+ unsigned index = ring.used->ring[head].id;
+
+ if ((index ^ guest.last_used_idx ^ 0x8000) & ~(ring_size - 1))
+ busy_wait();
+ else
+ break;
+ }
+#else
+ unsigned head = guest.last_used_idx;
+
+ while (ring.used->idx == head)
+ busy_wait();
+#endif
+}
+
+void disable_call()
+{
+ /* Doing nothing to disable calls might cause
+ * extra interrupts, but reduces the number of cache misses.
+ */
+}
+
+bool enable_call()
+{
+ unsigned short last_used_idx;
+
+ vring_used_event(&ring) = (last_used_idx = guest.last_used_idx);
+ /* Flush call index write */
+ /* Barrier D (for pairing) */
+ smp_mb();
+#ifdef RING_POLL
+ {
+ unsigned short head = last_used_idx & (ring_size - 1);
+ unsigned index = ring.used->ring[head].id;
+
+ return (index ^ last_used_idx ^ 0x8000) & ~(ring_size - 1);
+ }
+#else
+ return ring.used->idx == last_used_idx;
+#endif
+}
+
+void kick_available(void)
+{
+ /* Flush in previous flags write */
+ /* Barrier C (for pairing) */
+ smp_mb();
+ if (!vring_need_event(vring_avail_event(&ring),
+ guest.avail_idx,
+ guest.kicked_avail_idx))
+ return;
+
+ guest.kicked_avail_idx = guest.avail_idx;
+ kick();
+}
+
+/* host side */
+void disable_kick()
+{
+ /* Doing nothing to disable kicks might cause
+ * extra interrupts, but reduces the number of cache misses.
+ */
+}
+
+bool enable_kick()
+{
+ unsigned head = host.used_idx;
+
+ vring_avail_event(&ring) = head;
+ /* Barrier C (for pairing) */
+ smp_mb();
+#ifdef RING_POLL
+ {
+ unsigned index = ring.avail->ring[head & (ring_size - 1)];
+
+ return (index ^ head ^ 0x8000) & ~(ring_size - 1);
+ }
+#else
+ return head == ring.avail->idx;
+#endif
+}
+
+void poll_avail(void)
+{
+ unsigned head = host.used_idx;
+#ifdef RING_POLL
+ for (;;) {
+ unsigned index = ring.avail->ring[head & (ring_size - 1)];
+ if ((index ^ head ^ 0x8000) & ~(ring_size - 1))
+ busy_wait();
+ else
+ break;
+ }
+#else
+ while (ring.avail->idx == head)
+ busy_wait();
+#endif
+}
+
+bool use_buf(unsigned *lenp, void **bufp)
+{
+ unsigned used_idx = host.used_idx;
+ struct vring_desc *desc;
+ unsigned head;
+
+#ifdef RING_POLL
+ head = ring.avail->ring[used_idx & (ring_size - 1)];
+ if ((used_idx ^ head ^ 0x8000) & ~(ring_size - 1))
+ return false;
+ /* Barrier A (for pairing) */
+ smp_acquire();
+
+ used_idx &= ring_size - 1;
+ desc = &ring.desc[head & (ring_size - 1)];
+#else
+ if (used_idx == ring.avail->idx)
+ return false;
+
+ /* Barrier A (for pairing) */
+ smp_acquire();
+
+ used_idx &= ring_size - 1;
+ head = ring.avail->ring[used_idx];
+ desc = &ring.desc[head];
+#endif
+
+ *lenp = desc->len;
+ *bufp = (void *)(unsigned long)desc->addr;
+
+ /* now update used ring */
+ ring.used->ring[used_idx].id = head;
+ ring.used->ring[used_idx].len = desc->len - 1;
+ /* Barrier B (for pairing) */
+ smp_release();
+ host.used_idx++;
+ ring.used->idx = host.used_idx;
+
+ return true;
+}
+
+void call_used(void)
+{
+ /* Flush in previous flags write */
+ /* Barrier D (for pairing) */
+ smp_mb();
+ if (!vring_need_event(vring_used_event(&ring),
+ host.used_idx,
+ host.called_used_idx))
+ return;
+
+ host.called_used_idx = host.used_idx;
+ call();
+}
diff --git a/tools/virtio/ringtest/virtio_ring_poll.c b/tools/virtio/ringtest/virtio_ring_poll.c
new file mode 100644
index 0000000..84fc2c5
--- /dev/null
+++ b/tools/virtio/ringtest/virtio_ring_poll.c
@@ -0,0 +1,2 @@
+#define RING_POLL 1
+#include "virtio_ring_0_9.c"