Re: [Qemu-devel] [PATCH v8 07/16] gdbstub: add multiprocess support to (f|s)ThreadInfo and ThreadExtraInfo

[Max Filippov <jcmvbkbc@gmail.com>]

Hello,

On Fri, Dec 7, 2018 at 1:04 AM Luc Michel <luc.michel@greensocs.com> wrote:
>
> Change the thread info related packets handling to support multiprocess
> extension.
>
> Add the CPUs class name in the extra info to help differentiate
> them in multiprocess mode.
>
> Signed-off-by: Luc Michel <luc.michel@greensocs.com>
> Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
> Reviewed-by: Edgar E. Iglesias <edgar.iglesias@xilinx.com>
> ---
>  gdbstub.c | 37 +++++++++++++++++++++++++++----------
>  1 file changed, 27 insertions(+), 10 deletions(-)

Starting with this commit it is no longer possible to kill QEMU
with the 'kill' command from the gdb. This was a nice feature,
was this removal intentional, or is it just an implementation
bug?

> diff --git a/gdbstub.c b/gdbstub.c
> index bea0215f30..770915446a 100644
> --- a/gdbstub.c
> +++ b/gdbstub.c
> @@ -1267,11 +1267,10 @@ out:
>  static int gdb_handle_packet(GDBState *s, const char *line_buf)
>  {
>      CPUState *cpu;
>      CPUClass *cc;
>      const char *p;
> -    uint32_t thread;
>      uint32_t pid, tid;
>      int ch, reg_size, type, res;
>      uint8_t mem_buf[MAX_PACKET_LENGTH];
>      char buf[sizeof(mem_buf) + 1 /* trailing NUL */];
>      char thread_id[16];
> @@ -1563,30 +1562,48 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
>              snprintf(buf, sizeof(buf), "QC%s",
>                       gdb_fmt_thread_id(s, cpu, thread_id, sizeof(thread_id)));
>              put_packet(s, buf);
>              break;
>          } else if (strcmp(p,"fThreadInfo") == 0) {
> -            s->query_cpu = first_cpu;
> +            s->query_cpu = gdb_first_attached_cpu(s);
>              goto report_cpuinfo;
>          } else if (strcmp(p,"sThreadInfo") == 0) {
>          report_cpuinfo:
>              if (s->query_cpu) {
> -                snprintf(buf, sizeof(buf), "m%x", cpu_gdb_index(s->query_cpu));
> +                snprintf(buf, sizeof(buf), "m%s",
> +                         gdb_fmt_thread_id(s, s->query_cpu,
> +                                       thread_id, sizeof(thread_id)));
>                  put_packet(s, buf);
> -                s->query_cpu = CPU_NEXT(s->query_cpu);
> +                s->query_cpu = gdb_next_attached_cpu(s, s->query_cpu);
>              } else
>                  put_packet(s, "l");
>              break;
>          } else if (strncmp(p,"ThreadExtraInfo,", 16) == 0) {
> -            thread = strtoull(p+16, (char **)&p, 16);
> -            cpu = find_cpu(thread);
> +            if (read_thread_id(p + 16, &p, &pid, &tid) == GDB_READ_THREAD_ERR) {
> +                put_packet(s, "E22");
> +                break;
> +            }
> +            cpu = gdb_get_cpu(s, pid, tid);
>              if (cpu != NULL) {
>                  cpu_synchronize_state(cpu);
> -                /* memtohex() doubles the required space */
> -                len = snprintf((char *)mem_buf, sizeof(buf) / 2,
> -                               "CPU#%d [%s]", cpu->cpu_index,
> -                               cpu->halted ? "halted " : "running");
> +
> +                if (s->multiprocess && (s->process_num > 1)) {
> +                    /* Print the CPU model and name in multiprocess mode */
> +                    ObjectClass *oc = object_get_class(OBJECT(cpu));
> +                    const char *cpu_model = object_class_get_name(oc);
> +                    char *cpu_name =
> +                        object_get_canonical_path_component(OBJECT(cpu));
> +                    len = snprintf((char *)mem_buf, sizeof(buf) / 2,
> +                                   "%s %s [%s]", cpu_model, cpu_name,
> +                                   cpu->halted ? "halted " : "running");
> +                    g_free(cpu_name);
> +                } else {
> +                    /* memtohex() doubles the required space */
> +                    len = snprintf((char *)mem_buf, sizeof(buf) / 2,
> +                                   "CPU#%d [%s]", cpu->cpu_index,
> +                                   cpu->halted ? "halted " : "running");
> +                }
>                  trace_gdbstub_op_extra_info((char *)mem_buf);
>                  memtohex(buf, mem_buf, len);
>                  put_packet(s, buf);
>              }
>              break;
> --
> 2.19.2
>
>


-- 
Thanks.
-- Max