On 10/29/20 9:09 AM, Jens Axboe wrote: > Wire up TIF_NOTIFY_SIGNAL handling for arc. > > Cc:linux-arm-ker...@lists.infradead.org
Just to be clear, ARC and ARM seem to differ in 1 letter, they are in no way related :-) > Signed-off-by: Jens Axboe<ax...@kernel.dk> > --- > > 5.11 has support queued up for TIF_NOTIFY_SIGNAL, see this posting > for details: > > https://urldefense.com/v3/__https://lore.kernel.org/io-uring/20201026203230.386348-1-ax...@kernel.dk/__;!!A4F2R9G_pg!Oo4kwr6Yy8y5ByC8jIONjU28gLsqpyfzT10u5kfdsj2E-U2VIXQs7SvTmBRIkupZ$ > TL'DR ignore this url rewrite. Corporate mailer fudging the urls and I can't seem to find this msg in my mailing group subscription in Thunderbird (although it shows up in web achieve) hence need to reply from office account rather than the newsgroup account. > As part of that work, I'm adding TIF_NOTIFY_SIGNAL support to all archs, > as that will enable a set of cleanups once all of them support it. I'm > happy carrying this patch if need be, or it can be funelled through the > arch tree. Let me know. I'm fine either ways too, best to do whatever you are doing for other arches. Although this patch per se is broken, please see below. > > GET_CURR_THR_INFO_FLAGS r9 > - bbit0 r9, TIF_SIGPENDING, .Lchk_notify_resume > + and.f 0, r9, TIF_SIGPENDING|TIF_NOTIFY_SIGNAL, .Lchk_notify_resume This is not correct, AND is a simple ALU instruction with format: AND dest, src2, src1 With dest 0, it won't update any register. With .f suffix it would set CC flag based on ALU operation which can subsequent used for a predicated instruction such as BZ. So you need something like and.f 0, r9, TIF_SIGPENDING|TIF_NOTIFY_SIGNAL bz .Lchk_notify_resume > > ; Normal Trap/IRQ entry only saves Scratch (caller-saved) regs > ; in pt_reg since the "C" ABI (kernel code) will automatically > diff --git a/arch/arc/kernel/signal.c b/arch/arc/kernel/signal.c > index 2be55fb96d87..a78d8f745a67 100644 > --- a/arch/arc/kernel/signal.c > +++ b/arch/arc/kernel/signal.c > @@ -362,7 +362,7 @@ void do_signal(struct pt_regs *regs) > > restart_scall = in_syscall(regs) && syscall_restartable(regs); > > - if (get_signal(&ksig)) { > + if (test_thread_flag(TIF_SIGPENDING) && get_signal(&ksig)) { > if (restart_scall) { > arc_restart_syscall(&ksig.ka, regs); > syscall_wont_restart(regs); /* No more restarts */ I've not seen your entire patchset, but it seems we are now hitting do_signal() for either of TIF_{SIGPENDING|NOTIFY_SIGNAL} but then only handling signal for TIF_SIGPENDING, so why even bother to come here. Do you plan to add additional arch handling later ? Thx, -Vineet _______________________________________________ linux-snps-arc mailing list linux-snps-arc@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-snps-arc
