[Qemu-devel] [PATCH v3 41/50] tests/plugin: add sample plugins

["Alex Bennée" <alex.bennee@linaro.org>]

From: "Emilio G. Cota" <cota@braap.org>

Pass arguments with -plugin=libfoo.so,arg=bar,arg=baz

Signed-off-by: Emilio G. Cota <cota@braap.org>
---
 configure             |  4 +-
 tests/plugin/Makefile | 28 +++++++++++++
 tests/plugin/bb.c     | 66 ++++++++++++++++++++++++++++++
 tests/plugin/empty.c  | 30 ++++++++++++++
 tests/plugin/insn.c   | 63 +++++++++++++++++++++++++++++
 tests/plugin/mem.c    | 93 +++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 282 insertions(+), 2 deletions(-)
 create mode 100644 tests/plugin/Makefile
 create mode 100644 tests/plugin/bb.c
 create mode 100644 tests/plugin/empty.c
 create mode 100644 tests/plugin/insn.c
 create mode 100644 tests/plugin/mem.c

diff --git a/configure b/configure
index d3bf254191..2af8c436f2 100755
--- a/configure
+++ b/configure
@@ -7995,14 +7995,14 @@ fi
 # tests might fail. Prefer to keep the relevant files in their own
 # directory and symlink the directory instead.
 DIRS="tests tests/tcg tests/tcg/cris tests/tcg/lm32 tests/libqos tests/qapi-schema tests/tcg/xtensa tests/qemu-iotests tests/vm"
-DIRS="$DIRS tests/fp tests/qgraph"
+DIRS="$DIRS tests/fp tests/qgraph tests/plugin"
 DIRS="$DIRS docs docs/interop fsdev scsi"
 DIRS="$DIRS pc-bios/optionrom pc-bios/spapr-rtas pc-bios/s390-ccw"
 DIRS="$DIRS roms/seabios roms/vgabios"
 LINKS="Makefile tests/tcg/Makefile"
 LINKS="$LINKS tests/tcg/cris/Makefile tests/tcg/cris/.gdbinit"
 LINKS="$LINKS tests/tcg/lm32/Makefile tests/tcg/xtensa/Makefile po/Makefile"
-LINKS="$LINKS tests/fp/Makefile"
+LINKS="$LINKS tests/fp/Makefile tests/plugin/Makefile"
 LINKS="$LINKS pc-bios/optionrom/Makefile pc-bios/keymaps"
 LINKS="$LINKS pc-bios/spapr-rtas/Makefile"
 LINKS="$LINKS pc-bios/s390-ccw/Makefile"
diff --git a/tests/plugin/Makefile b/tests/plugin/Makefile
new file mode 100644
index 0000000000..f9a3546ea3
--- /dev/null
+++ b/tests/plugin/Makefile
@@ -0,0 +1,28 @@
+BUILD_DIR := $(CURDIR)/../..
+
+include $(BUILD_DIR)/config-host.mak
+include $(SRC_PATH)/rules.mak
+
+$(call set-vpath, $(SRC_PATH)/tests/plugin)
+
+NAMES :=
+NAMES += bb
+NAMES += empty
+NAMES += insn
+NAMES += mem
+
+SONAMES := $(addsuffix .so,$(addprefix lib,$(NAMES)))
+
+QEMU_CFLAGS += -fPIC
+QEMU_CFLAGS += -I$(SRC_PATH)/include/qemu
+
+all: $(SONAMES)
+
+lib%.so: %.o
+	$(CC) -shared -Wl,-soname,$@ -o $@ $^ $(LDLIBS)
+
+clean:
+	rm -f *.o *.so *.d
+	rm -Rf .libs
+
+.PHONY: all clean
diff --git a/tests/plugin/bb.c b/tests/plugin/bb.c
new file mode 100644
index 0000000000..bb868599a9
--- /dev/null
+++ b/tests/plugin/bb.c
@@ -0,0 +1,66 @@
+/*
+ * Copyright (C) 2018, Emilio G. Cota <cota@braap.org>
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ */
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include <qemu-plugin.h>
+
+static uint64_t bb_count;
+static uint64_t insn_count;
+static int stdout_fd;
+static bool do_inline;
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+    dprintf(stdout_fd, "bb's: %" PRIu64", insns: %" PRIu64 "\n",
+            bb_count, insn_count);
+}
+
+static void vcpu_tb_exec(unsigned int cpu_index, void *udata)
+{
+    unsigned long n_insns = (unsigned long)udata;
+
+    insn_count += n_insns;
+    bb_count++;
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, unsigned int cpu_index,
+                          struct qemu_plugin_tb *tb)
+{
+    unsigned long n_insns = qemu_plugin_tb_n_insns(tb);
+
+    if (do_inline) {
+        qemu_plugin_register_vcpu_tb_exec_inline(tb, QEMU_PLUGIN_INLINE_ADD_U64,
+                                                 &bb_count, 1);
+        qemu_plugin_register_vcpu_tb_exec_inline(tb, QEMU_PLUGIN_INLINE_ADD_U64,
+                                                 &insn_count, n_insns);
+    } else {
+        qemu_plugin_register_vcpu_tb_exec_cb(tb, vcpu_tb_exec,
+                                             QEMU_PLUGIN_CB_NO_REGS,
+                                             (void *)n_insns);
+    }
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, int argc,
+                                           char **argv)
+{
+    if (argc && strcmp(argv[0], "inline") == 0) {
+        do_inline = true;
+    }
+
+    /* to be used when in the exit hook */
+    stdout_fd = dup(STDOUT_FILENO);
+    assert(stdout_fd);
+
+    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+    qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+    return 0;
+}
diff --git a/tests/plugin/empty.c b/tests/plugin/empty.c
new file mode 100644
index 0000000000..b2e30bddb2
--- /dev/null
+++ b/tests/plugin/empty.c
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2018, Emilio G. Cota <cota@braap.org>
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ */
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include <qemu-plugin.h>
+
+/*
+ * Empty TB translation callback.
+ * This allows us to measure the overhead of injecting and then
+ * removing empty instrumentation.
+ */
+static void vcpu_tb_trans(qemu_plugin_id_t id, unsigned int cpu_index,
+                          struct qemu_plugin_tb *tb)
+{ }
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, int argc,
+                                           char **argv)
+{
+    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+    return 0;
+}
diff --git a/tests/plugin/insn.c b/tests/plugin/insn.c
new file mode 100644
index 0000000000..11afe0e8f1
--- /dev/null
+++ b/tests/plugin/insn.c
@@ -0,0 +1,63 @@
+/*
+ * Copyright (C) 2018, Emilio G. Cota <cota@braap.org>
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ */
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include <qemu-plugin.h>
+
+static int stdout_fd;
+static uint64_t insn_count;
+static bool do_inline;
+
+static void vcpu_insn_exec_before(unsigned int cpu_index, void *udata)
+{
+    insn_count++;
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, unsigned int cpu_index,
+                          struct qemu_plugin_tb *tb)
+{
+    size_t n = qemu_plugin_tb_n_insns(tb);
+    size_t i;
+
+    for (i = 0; i < n; i++) {
+        struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
+
+        if (do_inline) {
+            qemu_plugin_register_vcpu_insn_exec_inline(
+                insn, QEMU_PLUGIN_INLINE_ADD_U64, &insn_count, 1);
+        } else {
+            qemu_plugin_register_vcpu_insn_exec_cb(
+                insn, vcpu_insn_exec_before, QEMU_PLUGIN_CB_NO_REGS, NULL);
+        }
+    }
+}
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+    dprintf(stdout_fd, "insns: %" PRIu64 "\n", insn_count);
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, int argc,
+                                           char **argv)
+{
+    if (argc && !strcmp(argv[0], "inline")) {
+        do_inline = true;
+    }
+
+    /* to be used when in the exit hook */
+    stdout_fd = dup(STDOUT_FILENO);
+    assert(stdout_fd);
+
+    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+    qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+    return 0;
+}
diff --git a/tests/plugin/mem.c b/tests/plugin/mem.c
new file mode 100644
index 0000000000..c13c672c91
--- /dev/null
+++ b/tests/plugin/mem.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2018, Emilio G. Cota <cota@braap.org>
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ */
+#include <inttypes.h>
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdio.h>
+
+#include <qemu-plugin.h>
+
+static uint64_t mem_count;
+static int stdout_fd;
+static bool do_inline;
+static bool do_haddr;
+static enum qemu_plugin_mem_rw rw = QEMU_PLUGIN_MEM_RW;
+
+static void plugin_exit(qemu_plugin_id_t id, void *p)
+{
+    dprintf(stdout_fd, "accesses: %" PRIu64 "\n", mem_count);
+}
+
+static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
+                     uint64_t vaddr, void *udata)
+{
+    mem_count++;
+}
+
+static void vcpu_haddr(unsigned int cpu_index, qemu_plugin_meminfo_t meminfo,
+                       uint64_t vaddr, void *haddr, void *udata)
+{
+    mem_count++;
+}
+
+static void vcpu_tb_trans(qemu_plugin_id_t id, unsigned int cpu_index,
+                          struct qemu_plugin_tb *tb)
+{
+    size_t n = qemu_plugin_tb_n_insns(tb);
+    size_t i;
+
+    for (i = 0; i < n; i++) {
+        struct qemu_plugin_insn *insn = qemu_plugin_tb_get_insn(tb, i);
+
+        if (do_inline) {
+            qemu_plugin_register_vcpu_mem_inline(insn, rw,
+                                                 QEMU_PLUGIN_INLINE_ADD_U64,
+                                                 &mem_count, 1);
+        } else if (do_haddr) {
+            qemu_plugin_register_vcpu_mem_haddr_cb(insn, vcpu_haddr,
+                                                   QEMU_PLUGIN_CB_NO_REGS,
+                                                   rw, NULL);
+        } else {
+            qemu_plugin_register_vcpu_mem_cb(insn, vcpu_mem,
+                                             QEMU_PLUGIN_CB_NO_REGS,
+                                             rw, NULL);
+        }
+    }
+}
+
+QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plugin_id_t id, int argc,
+                                           char **argv)
+{
+    if (argc) {
+        if (argc >= 3) {
+            if (!strcmp(argv[2], "haddr")) {
+                do_haddr = true;
+            }
+        }
+        if (argc >= 2) {
+            const char *str = argv[1];
+
+            if (!strcmp(str, "r")) {
+                rw = QEMU_PLUGIN_MEM_R;
+            } else if (!strcmp(str, "w")) {
+                rw = QEMU_PLUGIN_MEM_W;
+            }
+        }
+        if (!strcmp(argv[0], "inline")) {
+            do_inline = true;
+        }
+    }
+    /* plugin_exit might write to stdout after stdout has been closed */
+    stdout_fd = dup(STDOUT_FILENO);
+    assert(stdout_fd);
+
+    qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans);
+    qemu_plugin_register_atexit_cb(id, plugin_exit, NULL);
+    return 0;
+}
-- 
2.20.1