cacheline aligned ?

["Rohit" <hoobastang@rediffmail.com>]

Hi,
    In softirq.c, statement
static struct softirq_action softirq_vec[32] 
__cacheline_aligned;

I am trying to figure out why this is cacheline_alligned.
I wrote a small piece of code to see how this may work ....

struct s {
    void (*action) (struct s *);
    int *data;
};

int main()
{
    int k;
    static struct s ss[32] __attribute__((__aligned__(32))) ;
    printf("first %x second %x \n",&ss[0],&ss[1]);
}

on executing this I get
> > > > first 80494e0 second 80494e8.
Which means the two elements of ss[] are 8 bytes apart. (ie sizeof 
struct s)

I achive the 32 byte alignment by modifing the code as below.
struct s {
    void (*action) (struct s *);
    int *data;
}__attribute__((__aligned__(32))) ;

and declaring
static struct s ss[32];

on executing I get
> > > > first 80494e0 second 8049500
ie 2 elemnts are 32 byte apart.

Please let me know what I am missing here.

Regards,
Rohit.
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