Hi Geert,
The main reason I thought my environment could be broken is because I
got the problem with iproute2 by Alexey!! Anyway I sent a mail to
Alexey to check with him.
Thanks,
Muthu
On Mon, 8 Jul 2002, Geert Uytterhoeven wrote:
> On Mon, 8 Jul 2002, Muthukumar Ratty wrote:
> > > I am not sure, but can this be memory allignment problem ?
> > > you can check this by adding one more (dummy ) element of __u32 length
> > > (MIPS
> > > should print 40 insted of 44 and pc shuld print 40 as expected )
> >
> > You are right. when I add a __u32 dummy to the tc_stats then it still
> > prints the size as 40. Is it get padded at the end? My main concern is,
> > is this a normal behavior or do I need to upgrade my MIPS build
> > environment?
>
> The alignment rule for 64-bit value is 8 bytes on MIPS, and only 4 bytes on
> ia32.
>
> Since sizeof(struct ...) must return a value that's a multiple of the
> alignment
> rule for the largest element in the struct, it returns 40 on MIPS.
>
> > Thanks a lot,
> > Muthu.
> >
> > >
> > > if it works then you can get rid of the above problem by changing the
> > > compilar settings.
> > >
> > > Regards,
> > > venkatesh M R
> > >
> > >
> > >
> > >
> > > Muthukumar Ratty wrote:
> > >
> > > > Hi,
> > > > In my MIPS system sizeof(struct tc_stats) returns 40 but it returns 36
> > > > in
> > > > i386 PC.
> > > >
> > > > tc_stats is defined in include/linux/pkt_sched.c as
> > > > struct tc_stats
> > > > {
> > > > __u64 bytes; /* NUmber of enqueues bytes */
> > > > __u32 packets; /* Number of enqueued packets
> > > > */
> > > > __u32 drops; /* Packets dropped because of
> > > > lack
> > > > of resources */
> > > > __u32 overlimits; /* Number of throttle events
> > > > when
> > > > this
> > > > * flow goes out of allocated
> > > > bandwidth*/
> > > > __u32 bps; /* Current flow byte rate */
> > > > __u32 pps; /* Current flow packet rate */
> > > > __u32 qlen;
> > > > __u32 backlog;
> > > > #ifdef __KERNEL__
> > > > spinlock_t *lock;
> > > > #endif
> > > > };
> > > > I printed the offsets of individual fields and they are same in i386 and
> > > > MIPS. If the "spinlock_t" is defined then this may be the case but I
> > > > am compiling an application, so it shouldnt be there? Right now I
> > > > think the problem could be with the "sizeof" operator.
> > > > Could someone please let me know if this is the case or I am doing
> > > > something wrong. Also any solution.
>
> Gr{oetje,eeting}s,
>
> Geert
>
> --
> Geert Uytterhoeven -- There's lots of Linux beyond ia32 --
> geert@linux-m68k.org
>
> In personal conversations with technical people, I call myself a hacker. But
> when I'm talking to journalists I just say "programmer" or something like
> that.
> -- Linus Torvalds
>
|