From: oza Pawandeep <oza.pawandeep@gmail.com>
To: Tom Tromey <tromey@redhat.com>
Cc: gdb@sourceware.org, gdb-patches@sourceware.org
Subject: Re: [design change] record-replay linux ABI level
Date: Sun, 13 May 2012 09:47:00 -0000 [thread overview]
Message-ID: <CAK1A=4y7d8ot_G+O8oFm_ZVDT9q7QdFu87hMXT=+mHfVuJPnTw@mail.gmail.com> (raw)
In-Reply-To: <CAK1A=4zRULTC9Tue8Wu7vYpCiHE-sWBLHU7P9uw0d8MO0YRUpA@mail.gmail.com>
following are the ARM syscalls.
/* 270 */ CALL(sys_arm_fadvise64_64)
CALL(sys_pciconfig_iobase)
CALL(sys_pciconfig_read)
CALL(sys_pciconfig_write)
CALL(sys_mq_open)
linux-record.h has a conflict at slot 271, 272 an so on..
sys_pciconfig_iobase is not defined at all.
It is confusing where to define in the enum gdb_syscall table.
current code looks like this...
static enum gdb_syscall
arm_canonicalize_syscall (int syscall)
{
enum { arm_sys_prlimit64 = 369 };
if (syscall <= arm_sys_prlimit64)
{
if (syscall <= gdb_sys_sched_getaffinity)
return syscall;
else if (syscall <= gdb_sys_fadvise64_64)
{
return (syscall + (unsigned int)2);
}
else
{
switch (syscall)
{
}
}
}
else
return -1;
}
It becomes clumsy as we start adding some more syscalls in the generic
structure. (even If we are able to find slots).
Regards,
Oza.
On Sun, May 13, 2012 at 1:03 PM, oza Pawandeep <oza.pawandeep@gmail.com> wrote:
> what I would do is, I will go ahead with curernt defination of enum.
> and try to provide mapping.
> if there are practical conflicts then I would seek for alternatives.
>
> Regards,
> Oza.
>
> On Sun, May 13, 2012 at 12:49 PM, oza Pawandeep <oza.pawandeep@gmail.com> wrote:
>> currently on i386 following is the function:
>>
>> static enum gdb_syscall
>> i386_canonicalize_syscall (int syscall)
>> {
>> enum { i386_syscall_max = 499 };
>>
>> if (syscall <= i386_syscall_max)
>> return syscall;
>> else
>> return -1;
>> }
>>
>> which is just straight mapping.
>>
>> If we use generic enum defination, we will end up adding some
>> additional syscalls for ARM and
>>
>> arm_canonicalize_syscall(int syscall)
>> end up having switch {case} and having one-to one mapping for some
>> syscalls and rest syscalls would be shift by 'n' position.
>> which looks clumsy to me.
>>
>>
>> I am trying to see if there is more generic way which would take care
>> of all archor move the defination to arch files.
>> will try to see what best could be done.
>>
>> Regards,
>> Oza.
>>
>>
>>
>> On Thu, May 10, 2012 at 7:09 PM, Tom Tromey <tromey@redhat.com> wrote:
>>> Oza> The definition of system call record maps fine to x86. but arm
>>> Oza> syscall numbers are different. [partially] for e.g. on x86 sycall
>>> Oza> number for sys_epoll_create = 254 while on ARM it is 250. the more
>>> Oza> we go down on defined system calls the more the numbers are
>>> Oza> differing on ARM and we loose one to one trivial mapping.
>>>
>>> My understanding of the current design is that the ARM code would see
>>> the syscall 250, and have a mapping to turn that into
>>> gdb_sys_epoll_create (== 254). This can be done bidirectionally with
>>> two lookup tables.
>>>
>>> I suppose this could still not work in some scenarios. One question is
>>> whether these occur in practice or are merely theoretical.
>>>
>>> I don't really care about this API either way.
>>> With a solid justification it is fine to change it.
>>>
>>> Tom
next prev parent reply other threads:[~2012-05-13 9:47 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <CAK1A=4xtgYd8hQEwHxjLQiv4eqhCu0cSRDmmbFJvBDJwDxUM+Q__46748.0269181125$1336555010$gmane$org@mail.gmail.com>
2012-05-09 20:39 ` Tom Tromey
2012-05-10 8:49 ` oza Pawandeep
[not found] ` <CAK1A=4xbh0M=yfc2MQpZdDCJEPnL3_z8=TA0VSE7qVCoO0Dn-Q__42617.423789534$1336639800$gmane$org@mail.gmail.com>
2012-05-10 13:39 ` Tom Tromey
2012-05-13 7:19 ` oza Pawandeep
2012-05-13 7:33 ` oza Pawandeep
2012-05-13 9:47 ` oza Pawandeep [this message]
2012-05-14 14:57 ` Joel Brobecker
2012-05-15 5:20 ` oza Pawandeep
2012-05-15 5:34 ` Joel Brobecker
[not found] ` <CAK1A=4yervLeVDQ-r49n95ftrB27u8K+R1hfstz1oFwTNX=t7Q__24807.0006179207$1337059251$gmane$org@mail.gmail.com>
2012-05-15 16:42 ` Tom Tromey
2012-05-16 10:48 ` oza Pawandeep
2012-05-16 14:57 ` Tom Tromey
2012-06-05 9:16 ` oza Pawandeep
2012-06-06 18:17 ` Tom Tromey
2012-06-05 9:19 ` oza Pawandeep
2012-05-09 9:16 oza Pawandeep
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