Merge tag 'pull-maintainer-updates-060324-1' of https://gitlab.com/stsquad/qemu into staging

maintainer updates (tests, gdbstub, plugins):

  - expand QOS_PATH_MAX_ELEMENT_SIZE to avoid LTO issues
  - support fork-follow-mode in gdbstub
  - new thread-safe scoreboard API for TCG plugins
  - suppress showing opcodes in plugin disassembly

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* tag 'pull-maintainer-updates-060324-1' of https://gitlab.com/stsquad/qemu: (29 commits)
  target/riscv: honour show_opcodes when disassembling
  target/loongarch: honour show_opcodes when disassembling
  disas/hppa: honour show_opcodes
  disas: introduce show_opcodes
  plugins: cleanup codepath for previous inline operation
  plugins: remove non per_vcpu inline operation from API
  contrib/plugins/howvec: migrate to new per_vcpu API
  contrib/plugins/hotblocks: migrate to new per_vcpu API
  tests/plugin/bb: migrate to new per_vcpu API
  tests/plugin/insn: migrate to new per_vcpu API
  tests/plugin/mem: migrate to new per_vcpu API
  tests/plugin: add test plugin for inline operations
  plugins: add inline operation per vcpu
  plugins: implement inline operation relative to cpu_index
  plugins: define qemu_plugin_u64
  plugins: scoreboard API
  tests/tcg: Add two follow-fork-mode tests
  gdbstub: Implement follow-fork-mode child
  gdbstub: Introduce gdb_handle_detach_user()
  gdbstub: Introduce gdb_handle_set_thread_user()
  ...

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

1 files changed, 113 insertions, 29 deletions

diff --git a/include/qemu/qemu-plugin.h b/include/qemu/qemu-plugin.h
index 45e2ebc8f8..4fc6c3739b 100644
--- a/include/qemu/qemu-plugin.h
+++ b/include/qemu/qemu-plugin.h
@@ -52,7 +52,11 @@ typedef uint64_t qemu_plugin_id_t;
  * The plugins export the API they were built against by exposing the
  * symbol qemu_plugin_version which can be checked.
  *
- * version 2: removed qemu_plugin_n_vcpus and qemu_plugin_n_max_vcpus
+ * version 2:
+ * - removed qemu_plugin_n_vcpus and qemu_plugin_n_max_vcpus
+ * - Remove qemu_plugin_register_vcpu_{tb, insn, mem}_exec_inline.
+ *   Those functions are replaced by *_per_vcpu variants, which guarantee
+ *   thread-safety for operations.
  */
 
 extern QEMU_PLUGIN_EXPORT int qemu_plugin_version;
@@ -222,6 +226,19 @@ void qemu_plugin_register_vcpu_resume_cb(qemu_plugin_id_t id,
 struct qemu_plugin_tb;
 /** struct qemu_plugin_insn - Opaque handle for a translated instruction */
 struct qemu_plugin_insn;
+/** struct qemu_plugin_scoreboard - Opaque handle for a scoreboard */
+struct qemu_plugin_scoreboard;
+
+/**
+ * typedef qemu_plugin_u64 - uint64_t member of an entry in a scoreboard
+ *
+ * This field allows to access a specific uint64_t member in one given entry,
+ * located at a specified offset. Inline operations expect this as entry.
+ */
+typedef struct {
+    struct qemu_plugin_scoreboard *score;
+    size_t offset;
+} qemu_plugin_u64;
 
 /**
  * enum qemu_plugin_cb_flags - type of callback
@@ -297,23 +314,20 @@ enum qemu_plugin_op {
 };
 
 /**
- * qemu_plugin_register_vcpu_tb_exec_inline() - execution inline op
+ * qemu_plugin_register_vcpu_tb_exec_inline_per_vcpu() - execution inline op
  * @tb: the opaque qemu_plugin_tb handle for the translation
  * @op: the type of qemu_plugin_op (e.g. ADD_U64)
- * @ptr: the target memory location for the op
+ * @entry: entry to run op
  * @imm: the op data (e.g. 1)
  *
- * Insert an inline op to every time a translated unit executes.
- * Useful if you just want to increment a single counter somewhere in
- * memory.
- *
- * Note: ops are not atomic so in multi-threaded/multi-smp situations
- * you will get inexact results.
+ * Insert an inline op on a given scoreboard entry.
  */
 QEMU_PLUGIN_API
-void qemu_plugin_register_vcpu_tb_exec_inline(struct qemu_plugin_tb *tb,
-                                              enum qemu_plugin_op op,
-                                              void *ptr, uint64_t imm);
+void qemu_plugin_register_vcpu_tb_exec_inline_per_vcpu(
+    struct qemu_plugin_tb *tb,
+    enum qemu_plugin_op op,
+    qemu_plugin_u64 entry,
+    uint64_t imm);
 
 /**
  * qemu_plugin_register_vcpu_insn_exec_cb() - register insn execution cb
@@ -331,19 +345,20 @@ void qemu_plugin_register_vcpu_insn_exec_cb(struct qemu_plugin_insn *insn,
                                             void *userdata);
 
 /**
- * qemu_plugin_register_vcpu_insn_exec_inline() - insn execution inline op
+ * qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu() - insn exec inline op
  * @insn: the opaque qemu_plugin_insn handle for an instruction
  * @op: the type of qemu_plugin_op (e.g. ADD_U64)
- * @ptr: the target memory location for the op
+ * @entry: entry to run op
  * @imm: the op data (e.g. 1)
  *
- * Insert an inline op to every time an instruction executes. Useful
- * if you just want to increment a single counter somewhere in memory.
+ * Insert an inline op to every time an instruction executes.
  */
 QEMU_PLUGIN_API
-void qemu_plugin_register_vcpu_insn_exec_inline(struct qemu_plugin_insn *insn,
-                                                enum qemu_plugin_op op,
-                                                void *ptr, uint64_t imm);
+void qemu_plugin_register_vcpu_insn_exec_inline_per_vcpu(
+    struct qemu_plugin_insn *insn,
+    enum qemu_plugin_op op,
+    qemu_plugin_u64 entry,
+    uint64_t imm);
 
 /**
  * qemu_plugin_tb_n_insns() - query helper for number of insns in TB
@@ -553,24 +568,23 @@ void qemu_plugin_register_vcpu_mem_cb(struct qemu_plugin_insn *insn,
                                       void *userdata);
 
 /**
- * qemu_plugin_register_vcpu_mem_inline() - register an inline op to any memory access
+ * qemu_plugin_register_vcpu_mem_inline_per_vcpu() - inline op for mem access
  * @insn: handle for instruction to instrument
  * @rw: apply to reads, writes or both
  * @op: the op, of type qemu_plugin_op
- * @ptr: pointer memory for the op
+ * @entry: entry to run op
  * @imm: immediate data for @op
  *
  * This registers a inline op every memory access generated by the
- * instruction. This provides for a lightweight but not thread-safe
- * way of counting the number of operations done.
+ * instruction.
  */
 QEMU_PLUGIN_API
-void qemu_plugin_register_vcpu_mem_inline(struct qemu_plugin_insn *insn,
-                                          enum qemu_plugin_mem_rw rw,
-                                          enum qemu_plugin_op op, void *ptr,
-                                          uint64_t imm);
-
-
+void qemu_plugin_register_vcpu_mem_inline_per_vcpu(
+    struct qemu_plugin_insn *insn,
+    enum qemu_plugin_mem_rw rw,
+    enum qemu_plugin_op op,
+    qemu_plugin_u64 entry,
+    uint64_t imm);
 
 typedef void
 (*qemu_plugin_vcpu_syscall_cb_t)(qemu_plugin_id_t id, unsigned int vcpu_index,
@@ -752,5 +766,75 @@ QEMU_PLUGIN_API
 int qemu_plugin_read_register(struct qemu_plugin_register *handle,
                               GByteArray *buf);
 
+/**
+ * qemu_plugin_scoreboard_new() - alloc a new scoreboard
+ *
+ * @element_size: size (in bytes) for one entry
+ *
+ * Returns a pointer to a new scoreboard. It must be freed using
+ * qemu_plugin_scoreboard_free.
+ */
+QEMU_PLUGIN_API
+struct qemu_plugin_scoreboard *qemu_plugin_scoreboard_new(size_t element_size);
+
+/**
+ * qemu_plugin_scoreboard_free() - free a scoreboard
+ * @score: scoreboard to free
+ */
+QEMU_PLUGIN_API
+void qemu_plugin_scoreboard_free(struct qemu_plugin_scoreboard *score);
+
+/**
+ * qemu_plugin_scoreboard_find() - get pointer to an entry of a scoreboard
+ * @score: scoreboard to query
+ * @vcpu_index: entry index
+ *
+ * Returns address of entry of a scoreboard matching a given vcpu_index. This
+ * address can be modified later if scoreboard is resized.
+ */
+QEMU_PLUGIN_API
+void *qemu_plugin_scoreboard_find(struct qemu_plugin_scoreboard *score,
+                                  unsigned int vcpu_index);
+
+/* Macros to define a qemu_plugin_u64 */
+#define qemu_plugin_scoreboard_u64(score) \
+    (qemu_plugin_u64) {score, 0}
+#define qemu_plugin_scoreboard_u64_in_struct(score, type, member) \
+    (qemu_plugin_u64) {score, offsetof(type, member)}
+
+/**
+ * qemu_plugin_u64_add() - add a value to a qemu_plugin_u64 for a given vcpu
+ * @entry: entry to query
+ * @vcpu_index: entry index
+ * @added: value to add
+ */
+QEMU_PLUGIN_API
+void qemu_plugin_u64_add(qemu_plugin_u64 entry, unsigned int vcpu_index,
+                         uint64_t added);
+
+/**
+ * qemu_plugin_u64_get() - get value of a qemu_plugin_u64 for a given vcpu
+ * @entry: entry to query
+ * @vcpu_index: entry index
+ */
+QEMU_PLUGIN_API
+uint64_t qemu_plugin_u64_get(qemu_plugin_u64 entry, unsigned int vcpu_index);
+
+/**
+ * qemu_plugin_u64_set() - set value of a qemu_plugin_u64 for a given vcpu
+ * @entry: entry to query
+ * @vcpu_index: entry index
+ * @val: new value
+ */
+QEMU_PLUGIN_API
+void qemu_plugin_u64_set(qemu_plugin_u64 entry, unsigned int vcpu_index,
+                         uint64_t val);
+
+/**
+ * qemu_plugin_u64_sum() - return sum of all vcpu entries in a scoreboard
+ * @entry: entry to sum
+ */
+QEMU_PLUGIN_API
+uint64_t qemu_plugin_u64_sum(qemu_plugin_u64 entry);
 
 #endif /* QEMU_QEMU_PLUGIN_H */