I was thinking the fsys_bubble_down is used to fall back to normal system call entry if that don't have a ligtweight handler. Is it right. On 10/16/07, Fenghua Yu <fenghua.yu@xxxxxxxxx> wrote: > On Mon, Oct 15, 2007 at 12:28:05PM +0800, Luming Yu wrote: > > So my problem is I don't know if it is true that pUStk == > > thread.on_ustack in fsys mode. And I didn't locate the code that the > > thread.on_ustack is cleared to 0 during fsys mode. > > So please help. > > In fsys call, pUStk is never equal to thread.on_ustack. Here is the code in > fsys_bubble_down() in fsys.S. > > .... > st1 [r16]=r0 // M2|3 clear current->thread.on_ustack flag > .... > cmp.ne pKStk,pUStk=r0,r0 // A set pKStk <- 0, pUStk <- 1 > .... > > The code shows that thread.on_ustack=0 and pUStk=1 during fsys setup phase. The > two should be equal in other cases than fsys. Seems the two similar names cause > confusion. > > Thanks. > > -Fenghua > - To unsubscribe from this list: send the line "unsubscribe linux-ia64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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