inline usage in C linux kernel

[rahul8143]

hello,
I have some inline declaration questions.
1)why new kernel 2.4.30 has intermediate function of __ instead of
direct calling it?
int ip_finish_outpu t(struct sk_buff *skb)
{
return __ip_finish_out put(skb);
}

and also __ip_finish_out put is written as
static __inline__ int __ip_finish_out put(struct sk_buff *skb)
what are these changes in kernel? Does they are for optimization?

2)Also ip_output is calling __ip_finish_out put instead ip_finish_outpu t
why?
3) what is difference between declaring following 2 inline functions
static inline int ip_finish_outpu t2(struct sk_buff *skb)
and
static __inline__ int __ip_finish_out put(struct sk_buff *skb)
please correct me.
regards,
rahul.

[Walter Roberson]

In article <11************ *********@z14g2 000cwz.googlegr oups.com>,
<ra*******@gmai l.com> wrote:

I have some inline declaration questions.
1)why new kernel 2.4.30 has intermediate function of __ instead of
direct calling it?
int ip_finish_outpu t(struct sk_buff *skb)
{
return __ip_finish_out put(skb);
}
You should ask that in a Linux developer's newsgroup, as it
is not a point that has to do with C itself.

3) what is difference between declaring following 2 inline functions
static inline int ip_finish_outpu t2(struct sk_buff *skb)
and
static __inline__ int __ip_finish_out put(struct sk_buff *skb)

'inline' is not part of C89 (I don't know about C99),
so the two could be there for reasons having to do with
two different implimentations of 'inline'.
--
'ignorandus (Latin): "deserving not to be known"'
-- Journal of Self-Referentialism

[Mark F. Haigh]

ra*******@gmail .com wrote:

hello,
I have some inline declaration questions.
1)why new kernel 2.4.30 has intermediate function of __ instead of
direct calling it?
int ip_finish_outpu t(struct sk_buff *skb)
{
return __ip_finish_out put(skb);
}

and also __ip_finish_out put is written as
static __inline__ int __ip_finish_out put(struct sk_buff *skb)
what are these changes in kernel? Does they are for optimization?

7.1.3 Reserved identifiers

[...]
-- All identifiers that begin with an underscore and
either an uppercase letter or another underscore are
always reserved for any use.

__ip_finish_out put is reserved for the implementation. In this case,
the implementors (the Linux kernel coders) have decided that this
roughly means "do not use for general kernel code; use it only if you
really know what you're doing." This is getting off-topic; see your
friendly Linux newsgroup for details (comp.os.linux. development*)

If you're not writing kernel or other very special purpose code, do not
ever infringe upon anything reserved for the implementation.

<snip> 3) what is difference between declaring following 2 inline functions
static inline int ip_finish_outpu t2(struct sk_buff *skb)
and
static __inline__ int __ip_finish_out put(struct sk_buff *skb)

Once again, by its double underscore prefix, __inline__ is reserved for
the implementation. In this case it's for the compiler, and offtopic
here, so go consult your version of gcc's manual for the details.
Mark F. Haigh
mf*****@sbcglob al.net

[Grumble]

rahul8143 wrote:

hello,
I have some inline declaration questions.
1)why new kernel 2.4.30 has intermediate function of __ instead of
direct calling it?
int ip_finish_outpu t(struct sk_buff *skb)
{
return __ip_finish_out put(skb);
}

Wrong newsgroup. Try comp.os.linux.d evelopment.syst em

[Christian Bau]

In article <11************ *********@z14g2 000cwz.googlegr oups.com>,
ra*******@gmail .com wrote:

hello,
I have some inline declaration questions.
1)why new kernel 2.4.30 has intermediate function of __ instead of
direct calling it?
int ip_finish_outpu t(struct sk_buff *skb)
{
return __ip_finish_out put(skb);
}

and also __ip_finish_out put is written as
static __inline__ int __ip_finish_out put(struct sk_buff *skb)
what are these changes in kernel? Does they are for optimization?

2)Also ip_output is calling __ip_finish_out put instead ip_finish_outpu t
why?
3) what is difference between declaring following 2 inline functions
static inline int ip_finish_outpu t2(struct sk_buff *skb)
and
static __inline__ int __ip_finish_out put(struct sk_buff *skb)
please correct me.
regards,

I looked through my copy of the C Standard, and I just couldn't find
this "new kernel 2.4.30" thing anywhere mentioned in it. Are you sure
you are posting to the right newsgroup here?