Re: [RFC PATCH 1/9] hurd: Move thread state manipulation into _hurd_tls_new ()

[Samuel Thibault]

Applied, thanks!

Sergey Bugaev, le sam. 18 févr. 2023 23:37:09 +0300, a ecrit:
> This is going to be done differently on x86_64.
> 
> Signed-off-by: Sergey Bugaev <bugaevc@gmail.com>
> ---
>  mach/setup-thread.c          | 18 ++----------------
>  sysdeps/mach/hurd/i386/tls.h | 25 ++++++++++++++++++++-----
>  2 files changed, 22 insertions(+), 21 deletions(-)
> 
> diff --git a/mach/setup-thread.c b/mach/setup-thread.c
> index 6ce5c13d..ae24a149 100644
> --- a/mach/setup-thread.c
> +++ b/mach/setup-thread.c
> @@ -83,25 +83,11 @@ weak_alias (__mach_setup_thread, mach_setup_thread)
>  kern_return_t
>  __mach_setup_tls (thread_t thread)
>  {
> -  kern_return_t error;
> -  struct machine_thread_state ts;
> -  mach_msg_type_number_t tssize = MACHINE_THREAD_STATE_COUNT;
> -  tcbhead_t *tcb;
> -
> -  tcb = _dl_allocate_tls (NULL);
> +  tcbhead_t *tcb = _dl_allocate_tls (NULL);
>    if (tcb == NULL)
>      return KERN_RESOURCE_SHORTAGE;
>  
> -  if (error = __thread_get_state (thread, MACHINE_THREAD_STATE_FLAVOR,
> -                          (natural_t *) &ts, &tssize))
> -    return error;
> -  assert (tssize == MACHINE_THREAD_STATE_COUNT);
> -
> -  _hurd_tls_new (thread, &ts, tcb);
> -
> -  error = __thread_set_state (thread, MACHINE_THREAD_STATE_FLAVOR,
> -                           (natural_t *) &ts, tssize);
> -  return error;
> +  return _hurd_tls_new (thread, tcb);
>  }
>  
>  weak_alias (__mach_setup_tls, mach_setup_tls)
> diff --git a/sysdeps/mach/hurd/i386/tls.h b/sysdeps/mach/hurd/i386/tls.h
> index 590abd47..0f8dd241 100644
> --- a/sysdeps/mach/hurd/i386/tls.h
> +++ b/sysdeps/mach/hurd/i386/tls.h
> @@ -378,16 +378,25 @@ _hurd_tls_fork (thread_t child, thread_t orig, struct 
> i386_thread_state *state)
>  }
>  
>  static inline kern_return_t __attribute__ ((unused))
> -_hurd_tls_new (thread_t child, struct i386_thread_state *state, tcbhead_t 
> *tcb)
> +_hurd_tls_new (thread_t child, tcbhead_t *tcb)
>  {
> +  error_t err;
> +  /* Fetch the target thread's state.  */
> +  struct i386_thread_state state;
> +  mach_msg_type_number_t state_count = i386_THREAD_STATE_COUNT;
> +  err = __thread_get_state (child, i386_REGS_SEGS_STATE,
> +                            (thread_state_t) &state,
> +                            &state_count);
> +  if (err)
> +    return err;
> +  assert (state_count == i386_THREAD_STATE_COUNT);
>    /* Fetch the selector set by _hurd_tls_init.  */
>    int sel;
>    asm ("mov %%gs, %w0" : "=q" (sel) : "0" (0));
> -  if (sel == state->ds)              /* _hurd_tls_init was never called.  */
> +  if (sel == state.ds)               /* _hurd_tls_init was never called.  */
>      return 0;
>  
>    HURD_TLS_DESC_DECL (desc, tcb);
> -  error_t err;
>  
>    tcb->tcb = tcb;
>    tcb->self = child;
> @@ -397,8 +406,14 @@ _hurd_tls_new (thread_t child, struct i386_thread_state 
> *state, tcbhead_t *tcb)
>    else
>      err = __i386_set_gdt (child, &sel, desc);
>  
> -  state->gs = sel;
> -  return err;
> +  if (err)
> +    return err;
> +
> +  /* Update gs to use the selector.  */
> +  state.gs = sel;
> +  return __thread_set_state (child, i386_REGS_SEGS_STATE,
> +                             (thread_state_t) &state,
> +                             state_count);
>  }
>  
>  /* Global scope switch support.  */
> -- 
> 2.39.2
> 
> 

-- 
Samuel
---
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