From: Shi Weihua This patch removes some redundant code in the function setup_sigcontext(). The registers ar.ccv,b7,r14,ar.csd,ar.ssd,r2-r3 and r16-r31 are not restored in restore_sigcontext() when (flags & IA64_SC_FLAG_IN_SYSCALL) is true. So we don't need to zero those variables in setup_sigcontext(). Signed-off-by: Shi Weihua Cc: "Luck, Tony" Signed-off-by: Andrew Morton --- arch/ia64/kernel/signal.c | 10 +--------- 1 file changed, 1 insertion(+), 9 deletions(-) diff -puN arch/ia64/kernel/signal.c~ia64-signal-remove-redundant-code-in-setup_sigcontext arch/ia64/kernel/signal.c --- a/arch/ia64/kernel/signal.c~ia64-signal-remove-redundant-code-in-setup_sigcontext +++ a/arch/ia64/kernel/signal.c @@ -280,15 +280,7 @@ setup_sigcontext (struct sigcontext __us err |= __copy_to_user(&sc->sc_gr[15], &scr->pt.r15, 8); /* r15 */ err |= __put_user(scr->pt.cr_iip + ia64_psr(&scr->pt)->ri, &sc->sc_ip); - if (flags & IA64_SC_FLAG_IN_SYSCALL) { - /* Clear scratch registers if the signal interrupted a system call. */ - err |= __put_user(0, &sc->sc_ar_ccv); /* ar.ccv */ - err |= __put_user(0, &sc->sc_br[7]); /* b7 */ - err |= __put_user(0, &sc->sc_gr[14]); /* r14 */ - err |= __clear_user(&sc->sc_ar25, 2*8); /* ar.csd & ar.ssd */ - err |= __clear_user(&sc->sc_gr[2], 2*8); /* r2-r3 */ - err |= __clear_user(&sc->sc_gr[16], 16*8); /* r16-r31 */ - } else { + if (!(flags & IA64_SC_FLAG_IN_SYSCALL)) { /* Copy scratch regs to sigcontext if the signal didn't interrupt a syscall. */ err |= __put_user(scr->pt.ar_ccv, &sc->sc_ar_ccv); /* ar.ccv */ err |= __put_user(scr->pt.b7, &sc->sc_br[7]); /* b7 */ _