Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761634Ab3DCQGT (ORCPT ); Wed, 3 Apr 2013 12:06:19 -0400 Received: from mx1.redhat.com ([209.132.183.28]:22138 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757722Ab3DCQGS (ORCPT ); Wed, 3 Apr 2013 12:06:18 -0400 From: Anton Arapov To: Anton Arapov , Oleg Nesterov , Srikar Dronamraju Cc: LKML , Josh Stone , Frank Eigler , Peter Zijlstra , Ingo Molnar , Ananth N Mavinakayanahalli , adrian.m.negreanu@intel.com, Torsten.Polle@gmx.de Subject: [PATCH v1 1/9] uretprobes: Introduce uprobe_consumer->ret_handler() Date: Wed, 3 Apr 2013 18:00:31 +0200 Message-Id: <1365004839-21982-2-git-send-email-anton@redhat.com> In-Reply-To: <1365004839-21982-1-git-send-email-anton@redhat.com> References: <1365004839-21982-1-git-send-email-anton@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2592 Lines: 80 Enclose return probes implementation, introduce ->ret_handler() and update existing code to rely on ->handler() *and* ->ret_handler() for uprobe and uretprobe respectively. v1 changes: * add bp_vaddr argument to ->ret_handler() RFCv5 changes: * don't remove uprobe in case there are no uprobe consumer(handler), see handler_chain() changes. RFCv3 changes: (the patch is introduced in v3) * check whether at least one of the consumer's handlers were set. * a 'TODO' cap that will be removed once return probes be implemented. * introduce ->ret_handler(). Signed-off-by: Anton Arapov --- include/linux/uprobes.h | 3 +++ kernel/events/uprobes.c | 17 ++++++++++++++--- 2 files changed, 17 insertions(+), 3 deletions(-) diff --git a/include/linux/uprobes.h b/include/linux/uprobes.h index 02b83db..4042cad 100644 --- a/include/linux/uprobes.h +++ b/include/linux/uprobes.h @@ -46,6 +46,9 @@ enum uprobe_filter_ctx { struct uprobe_consumer { int (*handler)(struct uprobe_consumer *self, struct pt_regs *regs); + int (*ret_handler)(struct uprobe_consumer *self, + unsigned long func, + struct pt_regs *regs); bool (*filter)(struct uprobe_consumer *self, enum uprobe_filter_ctx ctx, struct mm_struct *mm); diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 21d8a65..27c964b 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -815,6 +815,14 @@ int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer * struct uprobe *uprobe; int ret; + /* Uprobe must have at least one set consumer */ + if (!uc->handler && !uc->ret_handler) + return -EINVAL; + + /* TODO: Implement return probes */ + if (uc->ret_handler) + return -ENOSYS; + /* Racy, just to catch the obvious mistakes */ if (offset > i_size_read(inode)) return -EINVAL; @@ -1473,10 +1481,13 @@ static void handler_chain(struct uprobe *uprobe, struct pt_regs *regs) down_read(&uprobe->register_rwsem); for (uc = uprobe->consumers; uc; uc = uc->next) { - int rc = uc->handler(uc, regs); + int rc = 0; - WARN(rc & ~UPROBE_HANDLER_MASK, - "bad rc=0x%x from %pf()\n", rc, uc->handler); + if (uc->handler) { + rc = uc->handler(uc, regs); + WARN(rc & ~UPROBE_HANDLER_MASK, + "bad rc=0x%x from %pf()\n", rc, uc->handler); + } remove &= rc; } -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/