Correct way to format spufs file output.
arnd at arndb.de
Fri Oct 20 18:23:10 EST 2006
On Thursday 19 October 2006 05:30, Dwayne Grant McConnell wrote:
> In a recent submission I added the lslr file and used "%llx" for the
> format string. You mentioned that it should probably be "0x%llx" so it
> would be clearly parsed as hex so I changed it in the next submission. But
> I noticed that there seems to be some inconsistent usage of 0x as follows:
Thanks for bringing this up, I guess I screwed up in some way here, so
we should fix it up one way or another:
> signal1_type (%llu)
> signal2_type (%llu)
These are fine, they can only ever be 1 or 0.
> npc (%llx)
I think we used to access this in _very_ old versions of libspe,
before we move to a syscall based interface.
> decr (%llx)
> decr_status (%llx)
> spu_tag_mask (%llx)
> event_mask (%llx)
> event_status (%llx)
> srr0 (%llx)
These are used exclusively for debugging purposes, and no publically
available version of gdb accesses them, so I guess we can still change
them, although it's not nice.
> phys_id (0x%llx)
This one is used in some forks of libspe, we should not change it.
> object_id (0x%llx)
This is used in libspe, gdb and oprofile, but only in fairly recent
> lslr (0x%llx)
As this is introduced by your own patch, there is no precedent for
Current kernels now also have 'cntl' (0x%08lx), which was introduced
in 2.6.19 and is so far unused. I guess we should change that one
to be consistant with the others as well.
> Should all the %llx be changed to 0x%llx or should the 0x be dropped from
> those that have it or is the inconsistency acceptable?
I'd rather have it consistant. Moreover, I guess the "%llx" format is
actually harmful, because that means you can not use the same format
for read and write. The simple_attr_write function currently uses
the simple_strtol helper to interpret the value written to it, and that
requires the input to be wither decimal, or hexadecimal with a preceding
0x. I'd suggest we change all files to take a 0x%llx format on output.
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