From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 20 Oct 2006 08:54:37 -0500 (Central Daylight Time) From: Dwayne Grant McConnell To: Arnd Bergmann Subject: Re: Correct way to format spufs file output. In-Reply-To: <200610201023.12796.arnd@arndb.de> Message-ID: References: <200610201023.12796.arnd@arndb.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Cc: linuxppc-dev@ozlabs.org, cbe-oss-dev@ozlabs.org, linux-kernel@vger.kernel.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, 20 Oct 2006, Arnd Bergmann wrote: > 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 > versions. > > > lslr (0x%llx) > > As this is introduced by your own patch, there is no precedent for > it yet. > > 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. I think %0xllx is the way to go. I would even advocate changing signal1_type and signal2_type unless it is actually too dangerous. Is there even a case where changing from %llu to %0xllx would break things? Perhaps with the combination of a old library with a new kernel? -- Dwayne Grant McConnell Lotus Notes Mail: Dwayne McConnell [Mail]/Austin/IBM@IBMUS Lotus Notes Calendar: Dwayne McConnell [Calendar]/Austin/IBM@IBMUS