[lkml]   [2006]   [Dec]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: Mach-O binary format support and Darwin syscall personality [Was: uts banner changes]

On Wed, 13 Dec 2006, Benjamin Herrenschmidt wrote:
> > Secondly, is there a preferred existing field into which I should
> > stick said flag or just stuff it somewhere?
> Yes, thread_info->flags.

Well, it may actually make sense to actually stick the whole "syscall
table pointer" in there, rather than a flag that says which pointer to

We already load the thread_info pointer because we need the flags for
syscall tracing, and since we have the thread_info pointer, it might be
easier to load the syscall table pointer right off there, rather than
loading it as a big constant with "lis + ori" (in fact, on ppc64, we
currently load it off the TOC, which is really sad, since we already
brought in the thread_info into the cache, and usign the TOC is not just a
load, it's a load off a separate cacheline).

So on 64-bit ppc, it could actually speed things up to put the system call
table pointer into thread_info, and make it more flexible at the same
time, without any conditional flags.

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2009-11-18 23:46    [W:0.061 / U:1.372 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site