[PATCH] Disable get_ptrace_pid for NetBSD

[PATCH] Disable get_ptrace_pid for NetBSD

[Kamil Rytarowski]

Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
The process id on NetBSD is stored always in the pid field of ptid.

gdb/ChangeLog:

	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
	* inf-ptrace.c: Likewise.
	* (inf_ptrace_target::resume): Update.
	* (inf_ptrace_target::xfer_partial): Likewise.
---
 gdb/ChangeLog    |  7 +++++++
 gdb/inf-ptrace.c | 19 +++++++++++++++++--
 gdb/inf-ptrace.h |  2 ++
 3 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 84964dc00ac..36e333ec8ba 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,10 @@
+2020-03-18  Kamil Rytarowski  <n54@gmx.com>
+
+	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
+	* inf-ptrace.c: Likewise.
+	* (inf_ptrace_target::resume): Update.
+	* (inf_ptrace_target::xfer_partial): Likewise.
+
 2020-03-17  Kamil Rytarowski  <n54@gmx.com>

 	* regformats/regdef.h: Put reg in gdb namespace.
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index db17a76d946..e8bf66ed45f 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -313,8 +313,12 @@ inf_ptrace_target::kill ()
   target_mourn_inferior (inferior_ptid);
 }

+#ifndef __NetBSD__
 /* Return which PID to pass to ptrace in order to observe/control the
-   tracee identified by PTID.  */
+   tracee identified by PTID.
+
+   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
+   and avoids this function.  */

 pid_t
 get_ptrace_pid (ptid_t ptid)
@@ -328,6 +332,7 @@ get_ptrace_pid (ptid_t ptid)
     pid = ptid.pid ();
   return pid;
 }
+#endif

 /* Resume execution of thread PTID, or all threads if PTID is -1.  If
    STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
@@ -344,7 +349,13 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
        single-threaded processes, so simply resume the inferior.  */
     pid = inferior_ptid.pid ();
   else
-    pid = get_ptrace_pid (ptid);
+    {
+#ifdef __NetBSD__
+      pid = ptid. pid();
+#else
+      pid = get_ptrace_pid (ptid);
+#endif
+    }

   if (catch_syscall_enabled () > 0)
     request = PT_SYSCALL;
@@ -528,7 +539,11 @@ inf_ptrace_target::xfer_partial (enum target_object object,
 				 const gdb_byte *writebuf,
 				 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
 {
+#ifdef __NetBSD__
+  pid_t pid = inferior_ptid. pid();
+#else
   pid_t pid = get_ptrace_pid (inferior_ptid);
+#endif

   switch (object)
     {
diff --git a/gdb/inf-ptrace.h b/gdb/inf-ptrace.h
index dd0733736f2..340d41d8beb 100644
--- a/gdb/inf-ptrace.h
+++ b/gdb/inf-ptrace.h
@@ -78,9 +78,11 @@ struct inf_ptrace_target : public inf_child_target
   void detach_success (inferior *inf);
 };

+#ifndef __NetBSD__
 /* Return which PID to pass to ptrace in order to observe/control the
    tracee identified by PTID.  */

 extern pid_t get_ptrace_pid (ptid_t);
+#endif

 #endif
--
2.25.0

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Tom Tromey]

>>>>> "Kamil" == Kamil Rytarowski <n54@gmx.com> writes:

Kamil> Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
Kamil> The process id on NetBSD is stored always in the pid field of ptid.

Kamil> gdb/ChangeLog:

Kamil> 	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
Kamil> 	* inf-ptrace.c: Likewise.
Kamil> 	* (inf_ptrace_target::resume): Update.
Kamil> 	* (inf_ptrace_target::xfer_partial): Likewise.

Kamil> +#ifndef __NetBSD__
Kamil>  /* Return which PID to pass to ptrace in order to observe/control the
Kamil> -   tracee identified by PTID.  */
Kamil> +   tracee identified by PTID.
Kamil> +
Kamil> +   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
Kamil> +   and avoids this function.  */

Kamil>  pid_t
Kamil>  get_ptrace_pid (ptid_t ptid)
Kamil> @@ -328,6 +332,7 @@ get_ptrace_pid (ptid_t ptid)
Kamil>      pid = ptid.pid ();
Kamil>    return pid;

Why not make just the body of this function

#ifdef __NetBSD__
  return ptid.pid ()
#else
  ... old code


That would mean fewer #ifs.

Tom

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Tom Tromey]

>>>>> "Tom" == Tom Tromey <tom@tromey.com> writes:

Tom> Why not make just the body of this function

Tom> #ifdef __NetBSD__
Tom>   return ptid.pid ()
Tom> #else
Tom>   ... old code

Tom> That would mean fewer #ifs.

I see that's what you did originally and Simon requested this version.

Personally I think the new patch is uglier than the original, on the
basis that use of "#if" generally makes the code harder to understand.

Tom

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Simon Marchi]

On 2020-03-18 12:29 p.m., Kamil Rytarowski wrote:
> Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
> The process id on NetBSD is stored always in the pid field of ptid.
> 
> gdb/ChangeLog:
> 
> 	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
> 	* inf-ptrace.c: Likewise.
> 	* (inf_ptrace_target::resume): Update.
> 	* (inf_ptrace_target::xfer_partial): Likewise.
> ---
>  gdb/ChangeLog    |  7 +++++++
>  gdb/inf-ptrace.c | 19 +++++++++++++++++--
>  gdb/inf-ptrace.h |  2 ++
>  3 files changed, 26 insertions(+), 2 deletions(-)
> 
> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> index 84964dc00ac..36e333ec8ba 100644
> --- a/gdb/ChangeLog
> +++ b/gdb/ChangeLog
> @@ -1,3 +1,10 @@
> +2020-03-18  Kamil Rytarowski  <n54@gmx.com>
> +
> +	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
> +	* inf-ptrace.c: Likewise.
> +	* (inf_ptrace_target::resume): Update.
> +	* (inf_ptrace_target::xfer_partial): Likewise.
> +
>  2020-03-17  Kamil Rytarowski  <n54@gmx.com>
> 
>  	* regformats/regdef.h: Put reg in gdb namespace.
> diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
> index db17a76d946..e8bf66ed45f 100644
> --- a/gdb/inf-ptrace.c
> +++ b/gdb/inf-ptrace.c
> @@ -313,8 +313,12 @@ inf_ptrace_target::kill ()
>    target_mourn_inferior (inferior_ptid);
>  }
> 
> +#ifndef __NetBSD__
>  /* Return which PID to pass to ptrace in order to observe/control the
> -   tracee identified by PTID.  */
> +   tracee identified by PTID.
> +
> +   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
> +   and avoids this function.  */
> 
>  pid_t
>  get_ptrace_pid (ptid_t ptid)
> @@ -328,6 +332,7 @@ get_ptrace_pid (ptid_t ptid)
>      pid = ptid.pid ();
>    return pid;
>  }
> +#endif
> 
>  /* Resume execution of thread PTID, or all threads if PTID is -1.  If
>     STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
> @@ -344,7 +349,13 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
>         single-threaded processes, so simply resume the inferior.  */
>      pid = inferior_ptid.pid ();
>    else
> -    pid = get_ptrace_pid (ptid);
> +    {
> +#ifdef __NetBSD__
> +      pid = ptid. pid();
> +#else
> +      pid = get_ptrace_pid (ptid);
> +#endif
> +    }

To avoid the ifdefs in this more complex code, can't you use a gdb_ptrace function like in
the other patches?  This time, it would look like:

static int
gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
	    PTRACE_TYPE_ARG4 data)
{
#ifdef __NetBSD__
  return ptrace (request, ptid.pid (), addr, data);
#else
  pid_t pid = get_ptrace_pid (ptid);
  return ptrace (request, pid, addr, data);
#endif
}

Simon

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Simon Marchi]

On 2020-03-18 4:54 p.m., Tom Tromey wrote:
>>>>>> "Tom" == Tom Tromey <tom@tromey.com> writes:
> 
> Tom> Why not make just the body of this function
> 
> Tom> #ifdef __NetBSD__
> Tom>   return ptid.pid ()
> Tom> #else
> Tom>   ... old code
> 
> Tom> That would mean fewer #ifs.
> 
> I see that's what you did originally and Simon requested this version.
> 
> Personally I think the new patch is uglier than the original, on the
> basis that use of "#if" generally makes the code harder to understand.
> 
> Tom
> 

Indeed, I suggested that.  I am hoping that we can isolate the ifdefs in these
"gdb_ptrace" functions (we should probably find a better name for those...), to
which you pass a "ptid" and do the right thing according to the current OS.  I
agree that adding ifdefs in the more complex code is ugly and less readable.

If my suggestion doesn't work well in practice, then feel free to revert to your
original solution, I certainly don't want to impose it if it turns out not to be
a good idea.

Simon

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Kamil Rytarowski]

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On 18.03.2020 22:15, Simon Marchi wrote:
> On 2020-03-18 12:29 p.m., Kamil Rytarowski wrote:
>> Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
>> The process id on NetBSD is stored always in the pid field of ptid.
>>
>> gdb/ChangeLog:
>>
>> 	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
>> 	* inf-ptrace.c: Likewise.
>> 	* (inf_ptrace_target::resume): Update.
>> 	* (inf_ptrace_target::xfer_partial): Likewise.
>> ---
>>  gdb/ChangeLog    |  7 +++++++
>>  gdb/inf-ptrace.c | 19 +++++++++++++++++--
>>  gdb/inf-ptrace.h |  2 ++
>>  3 files changed, 26 insertions(+), 2 deletions(-)
>>
>> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
>> index 84964dc00ac..36e333ec8ba 100644
>> --- a/gdb/ChangeLog
>> +++ b/gdb/ChangeLog
>> @@ -1,3 +1,10 @@
>> +2020-03-18  Kamil Rytarowski  <n54@gmx.com>
>> +
>> +	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
>> +	* inf-ptrace.c: Likewise.
>> +	* (inf_ptrace_target::resume): Update.
>> +	* (inf_ptrace_target::xfer_partial): Likewise.
>> +
>>  2020-03-17  Kamil Rytarowski  <n54@gmx.com>
>>
>>  	* regformats/regdef.h: Put reg in gdb namespace.
>> diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
>> index db17a76d946..e8bf66ed45f 100644
>> --- a/gdb/inf-ptrace.c
>> +++ b/gdb/inf-ptrace.c
>> @@ -313,8 +313,12 @@ inf_ptrace_target::kill ()
>>    target_mourn_inferior (inferior_ptid);
>>  }
>>
>> +#ifndef __NetBSD__
>>  /* Return which PID to pass to ptrace in order to observe/control the
>> -   tracee identified by PTID.  */
>> +   tracee identified by PTID.
>> +
>> +   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
>> +   and avoids this function.  */
>>
>>  pid_t
>>  get_ptrace_pid (ptid_t ptid)
>> @@ -328,6 +332,7 @@ get_ptrace_pid (ptid_t ptid)
>>      pid = ptid.pid ();
>>    return pid;
>>  }
>> +#endif
>>
>>  /* Resume execution of thread PTID, or all threads if PTID is -1.  If
>>     STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
>> @@ -344,7 +349,13 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
>>         single-threaded processes, so simply resume the inferior.  */
>>      pid = inferior_ptid.pid ();
>>    else
>> -    pid = get_ptrace_pid (ptid);
>> +    {
>> +#ifdef __NetBSD__
>> +      pid = ptid. pid();
>> +#else
>> +      pid = get_ptrace_pid (ptid);
>> +#endif
>> +    }
> 
> To avoid the ifdefs in this more complex code, can't you use a gdb_ptrace function like in
> the other patches?  This time, it would look like:
> 
> static int
> gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
> 	    PTRACE_TYPE_ARG4 data)
> {
> #ifdef __NetBSD__
>   return ptrace (request, ptid.pid (), addr, data);
> #else
>   pid_t pid = get_ptrace_pid (ptid);
>   return ptrace (request, pid, addr, data);
> #endif
> }
> 
> Simon
> 

I will go for it, but only for a selection of ptrace () calls in this file.

In certain places there would need to be need to compose ptid_t out of
plain pid. Another case is PT_TRACE_ME.


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Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Simon Marchi]

On 2020-03-18 5:40 p.m., Kamil Rytarowski wrote:
> I will go for it, but only for a selection of ptrace () calls in this file.
> 
> In certain places there would need to be need to compose ptid_t out of
> plain pid. Another case is PT_TRACE_ME.

My understanding for those is that there's no difference between NetBSD and
the other platforms.

Simon

Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Kamil Rytarowski]

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On 18.03.2020 22:43, Simon Marchi wrote:
> On 2020-03-18 5:40 p.m., Kamil Rytarowski wrote:
>> I will go for it, but only for a selection of ptrace () calls in this file.
>>
>> In certain places there would need to be need to compose ptid_t out of
>> plain pid. Another case is PT_TRACE_ME.
> 
> My understanding for those is that there's no difference between NetBSD and
> the other platforms.
> 

This is correct, at least in the usage out there.

> Simon
> 



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Re: [PATCH] Disable get_ptrace_pid for NetBSD

[Kamil Rytarowski]

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On 18.03.2020 22:49, Kamil Rytarowski wrote:
> Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
> The process id on NetBSD is stored always in the pid field of ptid.
> 

There is is one bug.

I'm going to fix and submit a new version.

> gdb/ChangeLog:
> 
> 	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
> 	* inf-ptrace.c: Likewise.
> 	* (gdb_ptrace): Add.
> 	* (inf_ptrace_target::resume): Update.
> 	* (inf_ptrace_target::xfer_partial): Likewise.
> ---
>  gdb/ChangeLog    |  8 ++++++++
>  gdb/inf-ptrace.c | 32 +++++++++++++++++++++++---------
>  gdb/inf-ptrace.h |  2 ++
>  3 files changed, 33 insertions(+), 9 deletions(-)
> 
> diff --git a/gdb/ChangeLog b/gdb/ChangeLog
> index 84964dc00ac..406414cee76 100644
> --- a/gdb/ChangeLog
> +++ b/gdb/ChangeLog
> @@ -1,3 +1,11 @@
> +2020-03-18  Kamil Rytarowski  <n54@gmx.com>
> +
> +	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
> +	* inf-ptrace.c: Likewise.
> +	* (gdb_ptrace): Add.
> +	* (inf_ptrace_target::resume): Update.
> +	* (inf_ptrace_target::xfer_partial): Likewise.
> +
>  2020-03-17  Kamil Rytarowski  <n54@gmx.com>
> 
>  	* regformats/regdef.h: Put reg in gdb namespace.
> diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
> index db17a76d946..304a749f3f3 100644
> --- a/gdb/inf-ptrace.c
> +++ b/gdb/inf-ptrace.c
> @@ -37,6 +37,18 @@
> 
>  \f
> 
> +static int
> +gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
> +	    PTRACE_TYPE_ARG4 data)
> +{
> +#ifdef __NetBSD__
> +  return ptrace (request, ptid.pid (), addr, data);
> +#else
> +  pid_t pid = get_ptrace_pid (ptid);
> +  return ptrace (request, pid, addr, data);
> +#endif
> +}
> +
>  /* A unique_ptr helper to unpush a target.  */
> 
>  struct target_unpusher
> @@ -313,8 +325,12 @@ inf_ptrace_target::kill ()
>    target_mourn_inferior (inferior_ptid);
>  }
> 
> +#ifndef __NetBSD__
>  /* Return which PID to pass to ptrace in order to observe/control the
> -   tracee identified by PTID.  */
> +   tracee identified by PTID.
> +
> +   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
> +   and avoids this function.  */
> 
>  pid_t
>  get_ptrace_pid (ptid_t ptid)
> @@ -328,6 +344,7 @@ get_ptrace_pid (ptid_t ptid)
>      pid = ptid.pid ();
>    return pid;
>  }
> +#endif
> 
>  /* Resume execution of thread PTID, or all threads if PTID is -1.  If
>     STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
> @@ -336,15 +353,12 @@ get_ptrace_pid (ptid_t ptid)
>  void
>  inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
>  {
> -  pid_t pid;
>    int request;
> 
>    if (minus_one_ptid == ptid)
>      /* Resume all threads.  Traditionally ptrace() only supports
>         single-threaded processes, so simply resume the inferior.  */
> -    pid = inferior_ptid.pid ();
> -  else
> -    pid = get_ptrace_pid (ptid);
> +    ptid = inferior_ptid;
> 
>    if (catch_syscall_enabled () > 0)
>      request = PT_SYSCALL;
> @@ -365,7 +379,7 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
>       where it was.  If GDB wanted it to start some other way, we have
>       already written a new program counter value to the child.  */
>    errno = 0;
> -  ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
> +  gdb_ptrace (request, ptid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
>    if (errno != 0)
>      perror_with_name (("ptrace"));
>  }
> @@ -528,7 +542,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
>  				 const gdb_byte *writebuf,
>  				 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
>  {
> -  pid_t pid = get_ptrace_pid (inferior_ptid);
> +  ptid_t ptid = inferior_ptid;
> 
>    switch (object)
>      {
> @@ -552,7 +566,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
>  	piod.piod_len = len;
> 
>  	errno = 0;
> -	if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
> +	if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
>  	  {
>  	    /* Return the actual number of bytes read or written.  */
>  	    *xfered_len = piod.piod_len;
> @@ -588,7 +602,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
>  	piod.piod_len = len;
> 
>  	errno = 0;
> -	if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
> +	if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
>  	  {
>  	    /* Return the actual number of bytes read or written.  */
>  	    *xfered_len = piod.piod_len;
> diff --git a/gdb/inf-ptrace.h b/gdb/inf-ptrace.h
> index dd0733736f2..340d41d8beb 100644
> --- a/gdb/inf-ptrace.h
> +++ b/gdb/inf-ptrace.h
> @@ -78,9 +78,11 @@ struct inf_ptrace_target : public inf_child_target
>    void detach_success (inferior *inf);
>  };
> 
> +#ifndef __NetBSD__
>  /* Return which PID to pass to ptrace in order to observe/control the
>     tracee identified by PTID.  */
> 
>  extern pid_t get_ptrace_pid (ptid_t);
> +#endif
> 
>  #endif
> --
> 2.25.0
> 



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[PATCH] Disable get_ptrace_pid for NetBSD

[Kamil Rytarowski]

Unlike most other Operating Systems, NetBSD tracks both pid and lwp.
The process id on NetBSD is stored always in the pid field of ptid.

gdb/ChangeLog:

	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
	* inf-ptrace.c: Likewise.
	* (gdb_ptrace): Add.
	* (inf_ptrace_target::resume): Update.
	* (inf_ptrace_target::xfer_partial): Likewise.
---
 gdb/ChangeLog    |  8 ++++++++
 gdb/inf-ptrace.c | 32 +++++++++++++++++++++++---------
 gdb/inf-ptrace.h |  2 ++
 3 files changed, 33 insertions(+), 9 deletions(-)

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 84964dc00ac..406414cee76 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,11 @@
+2020-03-18  Kamil Rytarowski  <n54@gmx.com>
+
+	* inf-ptrace.h: Disable get_ptrace_pid on NetBSD.
+	* inf-ptrace.c: Likewise.
+	* (gdb_ptrace): Add.
+	* (inf_ptrace_target::resume): Update.
+	* (inf_ptrace_target::xfer_partial): Likewise.
+
 2020-03-17  Kamil Rytarowski  <n54@gmx.com>

 	* regformats/regdef.h: Put reg in gdb namespace.
diff --git a/gdb/inf-ptrace.c b/gdb/inf-ptrace.c
index db17a76d946..304a749f3f3 100644
--- a/gdb/inf-ptrace.c
+++ b/gdb/inf-ptrace.c
@@ -37,6 +37,18 @@

 \f

+static int
+gdb_ptrace (PTRACE_TYPE_ARG1 request, ptid_t ptid, PTRACE_TYPE_ARG3 addr,
+	    PTRACE_TYPE_ARG4 data)
+{
+#ifdef __NetBSD__
+  return ptrace (request, ptid.pid (), addr, data);
+#else
+  pid_t pid = get_ptrace_pid (ptid);
+  return ptrace (request, pid, addr, data);
+#endif
+}
+
 /* A unique_ptr helper to unpush a target.  */

 struct target_unpusher
@@ -313,8 +325,12 @@ inf_ptrace_target::kill ()
   target_mourn_inferior (inferior_ptid);
 }

+#ifndef __NetBSD__
 /* Return which PID to pass to ptrace in order to observe/control the
-   tracee identified by PTID.  */
+   tracee identified by PTID.
+
+   Unlike most other Operating Systems, NetBSD tracks both pid and lwp
+   and avoids this function.  */

 pid_t
 get_ptrace_pid (ptid_t ptid)
@@ -328,6 +344,7 @@ get_ptrace_pid (ptid_t ptid)
     pid = ptid.pid ();
   return pid;
 }
+#endif

 /* Resume execution of thread PTID, or all threads if PTID is -1.  If
    STEP is nonzero, single-step it.  If SIGNAL is nonzero, give it
@@ -336,15 +353,12 @@ get_ptrace_pid (ptid_t ptid)
 void
 inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
 {
-  pid_t pid;
   int request;

   if (minus_one_ptid == ptid)
     /* Resume all threads.  Traditionally ptrace() only supports
        single-threaded processes, so simply resume the inferior.  */
-    pid = inferior_ptid.pid ();
-  else
-    pid = get_ptrace_pid (ptid);
+    ptid = inferior_ptid;

   if (catch_syscall_enabled () > 0)
     request = PT_SYSCALL;
@@ -365,7 +379,7 @@ inf_ptrace_target::resume (ptid_t ptid, int step, enum gdb_signal signal)
      where it was.  If GDB wanted it to start some other way, we have
      already written a new program counter value to the child.  */
   errno = 0;
-  ptrace (request, pid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
+  gdb_ptrace (request, ptid, (PTRACE_TYPE_ARG3)1, gdb_signal_to_host (signal));
   if (errno != 0)
     perror_with_name (("ptrace"));
 }
@@ -528,7 +542,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
 				 const gdb_byte *writebuf,
 				 ULONGEST offset, ULONGEST len, ULONGEST *xfered_len)
 {
-  pid_t pid = get_ptrace_pid (inferior_ptid);
+  ptid_t ptid = inferior_ptid;

   switch (object)
     {
@@ -552,7 +566,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
 	piod.piod_len = len;

 	errno = 0;
-	if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+	if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
 	  {
 	    /* Return the actual number of bytes read or written.  */
 	    *xfered_len = piod.piod_len;
@@ -588,7 +602,7 @@ inf_ptrace_target::xfer_partial (enum target_object object,
 	piod.piod_len = len;

 	errno = 0;
-	if (ptrace (PT_IO, pid, (caddr_t)&piod, 0) == 0)
+	if (gdb_ptrace (PT_IO, ptid, (caddr_t)&piod, 0) == 0)
 	  {
 	    /* Return the actual number of bytes read or written.  */
 	    *xfered_len = piod.piod_len;
diff --git a/gdb/inf-ptrace.h b/gdb/inf-ptrace.h
index dd0733736f2..340d41d8beb 100644
--- a/gdb/inf-ptrace.h
+++ b/gdb/inf-ptrace.h
@@ -78,9 +78,11 @@ struct inf_ptrace_target : public inf_child_target
   void detach_success (inferior *inf);
 };

+#ifndef __NetBSD__
 /* Return which PID to pass to ptrace in order to observe/control the
    tracee identified by PTID.  */

 extern pid_t get_ptrace_pid (ptid_t);
+#endif

 #endif
--
2.25.0