Hi, On Thu, 3 May 2007, Andrew Morton wrote:
> > This finally renames the thread_info field in task structure to stack, > > so that the assumptions about this field are gone and archs have more > > freedom about placing the thread_info structure. > > It needed this build fix: > > --- a/include/asm-x86_64/system.h~rename-thread_info-to-stack-fix > +++ a/include/asm-x86_64/system.h > @@ -39,7 +39,7 @@ > [threadrsp] "i" (offsetof(struct task_struct, > thread.rsp)), \ > [ti_flags] "i" (offsetof(struct thread_info, flags)),\ > [tif_fork] "i" (TIF_FORK), \ > - [thread_info] "i" (offsetof(struct task_struct, > thread_info)), \ > + [thread_info] "i" (offsetof(struct task_struct, stack)), > \ > [pda_pcurrent] "i" (offsetof(struct x8664_pda, > pcurrent)) \ > : "memory", "cc" __EXTRA_CLOBBER) > > _ > > > It is unpleasing that this code is forced to implicitly assume that the > thing pointed to by task_struct.stack has type `struct thread_info'. > > Are we sure this patch is a good thing? Assembler code is difficult to wrap, there are more places where assembler code assumes that the thread_info is at the start of the stack. Anyway, in this case it looks a little weird that TIF_FORK needs to be cleared at every context switch, other archs setup a different return address (usually ret_from_fork) and then finish scheduling by calling schedule_tail(). bye, Roman - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
