Merge remote-tracking branch 'remotes/stsquad/tags/pull-tcg-plugins-281019-4' into staging

TCG Plugins initial implementation

  - use --enable-plugins @ configure
  - low impact introspection (-plugin empty.so to measure overhead)
  - plugins cannot alter guest state
  - example plugins included in source tree (tests/plugins)
  - -d plugin to enable plugin output in logs
  - check-tcg runs extra tests when plugins enabled
  - documentation in docs/devel/plugins.rst

# gpg: Signature made Mon 28 Oct 2019 15:13:23 GMT
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-tcg-plugins-281019-4: (57 commits)
  travis.yml: enable linux-gcc-debug-tcg cache
  MAINTAINERS: add me for the TCG plugins code
  scripts/checkpatch.pl: don't complain about (foo, /* empty */)
  .travis.yml: add --enable-plugins tests
  include/exec: wrap cpu_ldst.h in CONFIG_TCG
  accel/stubs: reduce headers from tcg-stub
  tests/plugin: add hotpages to analyse memory access patterns
  tests/plugin: add instruction execution breakdown
  tests/plugin: add a hotblocks plugin
  tests/tcg: enable plugin testing
  tests/tcg: drop test-i386-fprem from TESTS when not SLOW
  tests/tcg: move "virtual" tests to EXTRA_TESTS
  tests/tcg: set QEMU_OPTS for all cris runs
  tests/tcg/Makefile.target: fix path to config-host.mak
  tests/plugin: add sample plugins
  linux-user: support -plugin option
  vl: support -plugin option
  plugin: add qemu_plugin_outs helper
  plugin: add qemu_plugin_insn_disas helper
  plugin: expand the plugin_init function to include an info block
  ...

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

1 files changed, 97 insertions, 0 deletions

diff --git a/plugins/plugin.h b/plugins/plugin.h
new file mode 100644
index 0000000000..5482168d79
--- /dev/null
+++ b/plugins/plugin.h
@@ -0,0 +1,97 @@
+/*
+ * Plugin Shared Internal Functions
+ *
+ * Copyright (C) 2019, Linaro
+ *
+ * License: GNU GPL, version 2 or later.
+ *   See the COPYING file in the top-level directory.
+ *
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+#ifndef _PLUGIN_INTERNAL_H_
+#define _PLUGIN_INTERNAL_H_
+
+#include <gmodule.h>
+
+/* global state */
+struct qemu_plugin_state {
+    QTAILQ_HEAD(, qemu_plugin_ctx) ctxs;
+    QLIST_HEAD(, qemu_plugin_cb) cb_lists[QEMU_PLUGIN_EV_MAX];
+    /*
+     * Use the HT as a hash map by inserting k == v, which saves memory as
+     * documented by GLib. The parent struct is obtained with container_of().
+     */
+    GHashTable *id_ht;
+    /*
+     * Use the HT as a hash map. Note that we could use a list here,
+     * but with the HT we avoid adding a field to CPUState.
+     */
+    GHashTable *cpu_ht;
+    DECLARE_BITMAP(mask, QEMU_PLUGIN_EV_MAX);
+    /*
+     * @lock protects the struct as well as ctx->uninstalling.
+     * The lock must be acquired by all API ops.
+     * The lock is recursive, which greatly simplifies things, e.g.
+     * callback registration from qemu_plugin_vcpu_for_each().
+     */
+    QemuRecMutex lock;
+    /*
+     * HT of callbacks invoked from helpers. All entries are freed when
+     * the code cache is flushed.
+     */
+    struct qht dyn_cb_arr_ht;
+};
+
+
+struct qemu_plugin_ctx {
+    GModule *handle;
+    qemu_plugin_id_t id;
+    struct qemu_plugin_cb *callbacks[QEMU_PLUGIN_EV_MAX];
+    QTAILQ_ENTRY(qemu_plugin_ctx) entry;
+    /*
+     * keep a reference to @desc until uninstall, so that plugins do not have
+     * to strdup plugin args.
+     */
+    struct qemu_plugin_desc *desc;
+    bool installing;
+    bool uninstalling;
+    bool resetting;
+};
+
+struct qemu_plugin_ctx *plugin_id_to_ctx_locked(qemu_plugin_id_t id);
+
+void plugin_register_inline_op(GArray **arr,
+                               enum qemu_plugin_mem_rw rw,
+                               enum qemu_plugin_op op, void *ptr,
+                               uint64_t imm);
+
+void plugin_reset_uninstall(qemu_plugin_id_t id,
+                            qemu_plugin_simple_cb_t cb,
+                            bool reset);
+
+void plugin_register_cb(qemu_plugin_id_t id, enum qemu_plugin_event ev,
+                        void *func);
+
+void plugin_unregister_cb__locked(struct qemu_plugin_ctx *ctx,
+                                  enum qemu_plugin_event ev);
+
+void
+plugin_register_cb_udata(qemu_plugin_id_t id, enum qemu_plugin_event ev,
+                         void *func, void *udata);
+
+void
+plugin_register_dyn_cb__udata(GArray **arr,
+                              qemu_plugin_vcpu_udata_cb_t cb,
+                              enum qemu_plugin_cb_flags flags, void *udata);
+
+
+void plugin_register_vcpu_mem_cb(GArray **arr,
+                                 void *cb,
+                                 enum qemu_plugin_cb_flags flags,
+                                 enum qemu_plugin_mem_rw rw,
+                                 void *udata);
+
+void exec_inline_op(struct qemu_plugin_dyn_cb *cb);
+
+#endif /* _PLUGIN_INTERNAL_H_ */