From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756398Ab1GJSY7 (ORCPT ); Sun, 10 Jul 2011 14:24:59 -0400 Received: from mx1.redhat.com ([209.132.183.28]:51066 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756301Ab1GJSY5 (ORCPT ); Sun, 10 Jul 2011 14:24:57 -0400 Date: Sun, 10 Jul 2011 20:22:03 +0200 From: Oleg Nesterov To: Andrew Morton Cc: David Howells , David Woodhouse , Ingo Molnar , linux-kernel@vger.kernel.org Subject: [PATCH] x86: do_signal: simplify the TS_RESTORE_SIGMASK logic Message-ID: <20110710182203.GA27979@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 1. do_signal() looks at TS_RESTORE_SIGMASK and calculates the mask which should be stored in the signal frame, then it passes "oldset" to the callees, down to setup_rt_frame(). This is ugly, setup_rt_frame() can do this itself and nobody else needs this sigset_t. Move this code into setup_rt_frame. 2. do_signal() also clears TS_RESTORE_SIGMASK if handle_signal() succeeds. We can move this to setup_rt_frame() as well, this avoids the unnecessary checks and makes the logic more clear. 3. use set_current_blocked() instead of sigprocmask(SIG_SETMASK), sigprocmask() should be avoided. Signed-off-by: Oleg Nesterov --- arch/x86/kernel/signal.c | 29 ++++++++++------------------- 1 file changed, 10 insertions(+), 19 deletions(-) --- ptrace/arch/x86/kernel/signal.c~2_restore_sigmask 2011-07-10 18:06:30.000000000 +0200 +++ ptrace/arch/x86/kernel/signal.c 2011-07-10 19:45:21.000000000 +0200 @@ -653,11 +653,15 @@ int ia32_setup_frame(int sig, struct k_s static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, - sigset_t *set, struct pt_regs *regs) + struct pt_regs *regs) { int usig = signr_convert(sig); + sigset_t *set = ¤t->blocked; int ret; + if (current_thread_info()->status & TS_RESTORE_SIGMASK) + set = ¤t->saved_sigmask; + /* Set up the stack frame */ if (is_ia32) { if (ka->sa.sa_flags & SA_SIGINFO) @@ -672,12 +676,13 @@ setup_rt_frame(int sig, struct k_sigacti return -EFAULT; } + current_thread_info()->status &= ~TS_RESTORE_SIGMASK; return ret; } static int handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, - sigset_t *oldset, struct pt_regs *regs) + struct pt_regs *regs) { sigset_t blocked; int ret; @@ -712,7 +717,7 @@ handle_signal(unsigned long sig, siginfo likely(test_and_clear_thread_flag(TIF_FORCED_TF))) regs->flags &= ~X86_EFLAGS_TF; - ret = setup_rt_frame(sig, ka, info, oldset, regs); + ret = setup_rt_frame(sig, ka, info, regs); if (ret) return ret; @@ -758,7 +763,6 @@ static void do_signal(struct pt_regs *re struct k_sigaction ka; siginfo_t info; int signr; - sigset_t *oldset; /* * We want the common case to go fast, which is why we may in certain @@ -770,23 +774,10 @@ static void do_signal(struct pt_regs *re if (!user_mode(regs)) return; - if (current_thread_info()->status & TS_RESTORE_SIGMASK) - oldset = ¤t->saved_sigmask; - else - oldset = ¤t->blocked; - signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { /* Whee! Actually deliver the signal. */ - if (handle_signal(signr, &info, &ka, oldset, regs) == 0) { - /* - * A signal was successfully delivered; the saved - * sigmask will have been stored in the signal frame, - * and will be restored by sigreturn, so we can simply - * clear the TS_RESTORE_SIGMASK flag. - */ - current_thread_info()->status &= ~TS_RESTORE_SIGMASK; - } + handle_signal(signr, &info, &ka, regs); return; } @@ -814,7 +805,7 @@ static void do_signal(struct pt_regs *re */ if (current_thread_info()->status & TS_RESTORE_SIGMASK) { current_thread_info()->status &= ~TS_RESTORE_SIGMASK; - sigprocmask(SIG_SETMASK, ¤t->saved_sigmask, NULL); + set_current_blocked(¤t->saved_sigmask); } }