Re: [PATCH v5 7/9] gdbstub: Make get cpu and hex conversion functions non-internal

[Philippe Mathieu-Daudé]

On 27/6/24 13:05, Alex Bennée wrote:

Philippe Mathieu-Daudé <phi...@linaro.org> writes:

On 27/6/24 06:13, Gustavo Romero wrote:

Make the gdb_first_attached_cpu and gdb_hextomem non-internal so they
are not confined to use only in gdbstub.c.
Signed-off-by: Gustavo Romero <gustavo.rom...@linaro.org>
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
---
   gdbstub/internals.h        | 2 --
   include/exec/gdbstub.h     | 5 +++++
   include/gdbstub/commands.h | 6 ++++++
   3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index 1bd2c4ec2a..77e5ec9a5b 100644
--- a/include/exec/gdbstub.h
+++ b/include/exec/gdbstub.h
@@ -135,4 +135,9 @@ void gdb_set_stop_cpu(CPUState *cpu);
   /* in gdbstub-xml.c, generated by scripts/feature_to_c.py */
   extern const GDBFeature gdb_static_features[];
   +/**
+ * Return the first attached CPU
+ */
+CPUState *gdb_first_attached_cpu(void);

Alex, it seems dubious to expose the API like that.

IMHO GdbCmdHandler should take a GDBRegisterState argument,
then this would become:

   CPUState *gdb_first_attached_cpu(GDBRegisterState *s);

Maybe instead of exposing this we can use user_ctx for something? If we
look at handle_set_reg/handle_get_reg we can see that passes down
gdbserver_state.g_cpu down to the eventual helpers. We could define
something like:

--8<---------------cut here---------------start------------->8---
fixups to avoid get_first_cpu()

5 files changed, 25 insertions(+), 18 deletions(-)
gdbstub/internals.h        |  1 +
include/exec/gdbstub.h     |  5 -----
include/gdbstub/commands.h |  3 +++
gdbstub/gdbstub.c          |  7 ++++++-
target/arm/gdbstub64.c     | 27 +++++++++++++++------------

@@ -54,6 +54,8 @@ typedef union GdbCmdVariant {
   * "stop reply" packet. The list of commands that accept such response is
   * defined at the GDB Remote Serial Protocol documentation. See:
   * 
https://sourceware.org/gdb/onlinedocs/gdb/Stop-Reply-Packets.html#Stop-Reply-Packets.
+ *
+ * @need_cpu_context: pass current CPU to command via user_ctx.
   */
  typedef struct GdbCmdParseEntry {
      GdbCmdHandler handler;
@@ -61,6 +63,7 @@ typedef struct GdbCmdParseEntry {
      bool cmd_startswith;
      const char *schema;
      bool allow_stop_reply;
+    bool need_cpu_context;
  } GdbCmdParseEntry;

#define get_cmd_parsers(p) (&g_array_index(p, GdbCmdParseEntry, 0))

modified   gdbstub/gdbstub.c
@@ -938,6 +938,7 @@ static bool process_string_cmd(const char *data,

for (i = 0; i < num_cmds; i++) {

          const GdbCmdParseEntry *cmd = &cmds[i];
+        void *user_ctx = NULL;
          g_assert(cmd->handler && cmd->cmd);

if ((cmd->cmd_startswith && !startswith(data, cmd->cmd)) ||

@@ -952,8 +953,12 @@ static bool process_string_cmd(const char *data,
              }
          }

+ if (cmd->need_cpu_context) {

+            user_ctx = (void *) gdbserver_state.g_cpu;

LGTM.

+        }
+
          gdbserver_state.allow_stop_reply = cmd->allow_stop_reply;
-        cmd->handler(params, NULL);
+        cmd->handler(params, user_ctx);
          return true;
      }