From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754823Ab2LCPJu (ORCPT ); Mon, 3 Dec 2012 10:09:50 -0500 Received: from e28smtp05.in.ibm.com ([122.248.162.5]:58851 "EHLO e28smtp05.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752813Ab2LCPJt (ORCPT ); Mon, 3 Dec 2012 10:09:49 -0500 Subject: [PATCH v2 3/4] uprobes/powerpc: Introduce routines for save/restore context To: bigeasy@linutronix.de, oleg@redhat.com, ananth@in.ibm.com, srikar@linux.vnet.ibm.com From: "Suzuki K. Poulose" Cc: peterz@infradead.org, benh@kernel.crashing.org, mingo@elte.hu, anton@redhat.com, linux-kernel@vger.kernel.org Date: Mon, 03 Dec 2012 20:39:35 +0530 Message-ID: <20121203150849.7727.53296.stgit@suzukikp> In-Reply-To: <20121203150438.7727.74924.stgit@suzukikp> References: <20121203150438.7727.74924.stgit@suzukikp> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12120315-8256-0000-0000-00000547772E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Suzuki K. Poulose Introduce routines for saving and restoring the context befre/after the single step. No functional changes involved. These will be extended later to save/restore more info about the process once we replace the ptrace helpers. Signed-off-by: Suzuki K. Poulose --- arch/powerpc/kernel/uprobes.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/uprobes.c b/arch/powerpc/kernel/uprobes.c index bc77834..1a62353 100644 --- a/arch/powerpc/kernel/uprobes.c +++ b/arch/powerpc/kernel/uprobes.c @@ -52,6 +52,16 @@ int arch_uprobe_analyze_insn(struct arch_uprobe *auprobe, return 0; } +static void uprobe_save_context_sstep(struct arch_uprobe_task *autask) +{ + autask->saved_trap_nr = current->thread.trap_nr; +} + +static void uprobe_restore_context_sstep(struct arch_uprobe_task *autask) +{ + current->thread.trap_nr = autask->saved_trap_nr; +} + /* * arch_uprobe_pre_xol - prepare to execute out of line. * @auprobe: the probepoint information. @@ -61,7 +71,7 @@ int arch_uprobe_pre_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) { struct arch_uprobe_task *autask = ¤t->utask->autask; - autask->saved_trap_nr = current->thread.trap_nr; + uprobe_save_context_sstep(autask); current->thread.trap_nr = UPROBE_TRAP_NR; regs->nip = current->utask->xol_vaddr; @@ -111,7 +121,7 @@ int arch_uprobe_post_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) WARN_ON_ONCE(current->thread.trap_nr != UPROBE_TRAP_NR); - current->thread.trap_nr = utask->autask.saved_trap_nr; + uprobe_restore_context_sstep(&utask->autask); /* * On powerpc, except for loads and stores, most instructions @@ -164,7 +174,7 @@ void arch_uprobe_abort_xol(struct arch_uprobe *auprobe, struct pt_regs *regs) { struct uprobe_task *utask = current->utask; - current->thread.trap_nr = utask->autask.saved_trap_nr; + uprobe_restore_context_sstep(&utask->autask); instruction_pointer_set(regs, utask->vaddr); user_disable_single_step(current);