Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753497AbYKKU6v (ORCPT ); Tue, 11 Nov 2008 15:58:51 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752442AbYKKU55 (ORCPT ); Tue, 11 Nov 2008 15:57:57 -0500 Received: from mx2.redhat.com ([66.187.237.31]:39822 "EHLO mx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753117AbYKKU54 (ORCPT ); Tue, 11 Nov 2008 15:57:56 -0500 Message-ID: <4919F1A9.5070601@redhat.com> Date: Tue, 11 Nov 2008 15:57:13 -0500 From: Masami Hiramatsu User-Agent: Thunderbird 2.0.0.16 (X11/20080723) MIME-Version: 1.0 To: Andrew Morton CC: Ananth N Mavinakayanahalli , Jim Keniston , David Miller , Rusty Russell , LKML , systemtap-ml Subject: [PATCH 5/7] kprobes: Remove called_from argument X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5800 Lines: 205 Remove called_from argument from kprobes which had been used for preventing self-refering of kernel module. However, since we don't keep module's refcount after registering kprobe any more, there is no reason to check that. This patch also simplifies registering/unregistering functions because we don't need to use __builtin_return_address(0) which was passed to called_from. Signed-off-by: Masami Hiramatsu --- kernel/kprobes.c | 70 +++++++++++-------------------------------------------- 1 file changed, 14 insertions(+), 56 deletions(-) Index: 2.6.28-rc4/kernel/kprobes.c =================================================================== --- 2.6.28-rc4.orig/kernel/kprobes.c +++ 2.6.28-rc4/kernel/kprobes.c @@ -641,8 +641,7 @@ static kprobe_opcode_t __kprobes *kprobe return (kprobe_opcode_t *)(((char *)addr) + p->offset); } -static int __kprobes __register_kprobe(struct kprobe *p, - unsigned long called_from) +int __kprobes register_kprobe(struct kprobe *p) { int ret = 0; struct kprobe *old_p; @@ -673,13 +672,10 @@ static int __kprobes __register_kprobe(s * We must hold a refcount of the probed module while updating * its code to prohibit unexpected unloading. */ - if (calling_mod != probed_mod) { - if (unlikely(!try_module_get(probed_mod))) { - preempt_enable(); - return -EINVAL; - } - } else - probed_mod = NULL; + if (unlikely(!try_module_get(probed_mod))) { + preempt_enable(); + return -EINVAL; + } } preempt_enable(); @@ -773,15 +769,14 @@ static void __kprobes __unregister_kprob } } -static int __kprobes __register_kprobes(struct kprobe **kps, int num, - unsigned long called_from) +int __kprobes register_kprobes(struct kprobe **kps, int num) { int i, ret = 0; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { - ret = __register_kprobe(kps[i], called_from); + ret = register_kprobe(kps[i]); if (ret < 0) { if (i > 0) unregister_kprobes(kps, i); @@ -791,26 +786,11 @@ static int __kprobes __register_kprobes( return ret; } -/* - * Registration and unregistration functions for kprobe. - */ -int __kprobes register_kprobe(struct kprobe *p) -{ - return __register_kprobes(&p, 1, - (unsigned long)__builtin_return_address(0)); -} - void __kprobes unregister_kprobe(struct kprobe *p) { unregister_kprobes(&p, 1); } -int __kprobes register_kprobes(struct kprobe **kps, int num) -{ - return __register_kprobes(kps, num, - (unsigned long)__builtin_return_address(0)); -} - void __kprobes unregister_kprobes(struct kprobe **kps, int num) { int i; @@ -839,8 +819,7 @@ unsigned long __weak arch_deref_entry_po return (unsigned long)entry; } -static int __kprobes __register_jprobes(struct jprobe **jps, int num, - unsigned long called_from) +int __kprobes register_jprobes(struct jprobe **jps, int num) { struct jprobe *jp; int ret = 0, i; @@ -858,7 +837,7 @@ static int __kprobes __register_jprobes( /* Todo: Verify probepoint is a function entry point */ jp->kp.pre_handler = setjmp_pre_handler; jp->kp.break_handler = longjmp_break_handler; - ret = __register_kprobe(&jp->kp, called_from); + ret = register_kprobe(&jp->kp); } if (ret < 0) { if (i > 0) @@ -871,8 +850,7 @@ static int __kprobes __register_jprobes( int __kprobes register_jprobe(struct jprobe *jp) { - return __register_jprobes(&jp, 1, - (unsigned long)__builtin_return_address(0)); + return register_jprobes(&jp, 1); } void __kprobes unregister_jprobe(struct jprobe *jp) @@ -880,12 +858,6 @@ void __kprobes unregister_jprobe(struct unregister_jprobes(&jp, 1); } -int __kprobes register_jprobes(struct jprobe **jps, int num) -{ - return __register_jprobes(jps, num, - (unsigned long)__builtin_return_address(0)); -} - void __kprobes unregister_jprobes(struct jprobe **jps, int num) { int i; @@ -948,8 +920,7 @@ static int __kprobes pre_handler_kretpro return 0; } -static int __kprobes __register_kretprobe(struct kretprobe *rp, - unsigned long called_from) +int __kprobes register_kretprobe(struct kretprobe *rp) { int ret = 0; struct kretprobe_instance *inst; @@ -995,21 +966,20 @@ static int __kprobes __register_kretprob rp->nmissed = 0; /* Establish function entry probe point */ - ret = __register_kprobe(&rp->kp, called_from); + ret = register_kprobe(&rp->kp); if (ret != 0) free_rp_inst(rp); return ret; } -static int __kprobes __register_kretprobes(struct kretprobe **rps, int num, - unsigned long called_from) +int __kprobes register_kretprobes(struct kretprobe **rps, int num) { int ret = 0, i; if (num <= 0) return -EINVAL; for (i = 0; i < num; i++) { - ret = __register_kretprobe(rps[i], called_from); + ret = register_kretprobe(rps[i]); if (ret < 0) { if (i > 0) unregister_kretprobes(rps, i); @@ -1019,23 +989,11 @@ static int __kprobes __register_kretprob return ret; } -int __kprobes register_kretprobe(struct kretprobe *rp) -{ - return __register_kretprobes(&rp, 1, - (unsigned long)__builtin_return_address(0)); -} - void __kprobes unregister_kretprobe(struct kretprobe *rp) { unregister_kretprobes(&rp, 1); } -int __kprobes register_kretprobes(struct kretprobe **rps, int num) -{ - return __register_kretprobes(rps, num, - (unsigned long)__builtin_return_address(0)); -} - void __kprobes unregister_kretprobes(struct kretprobe **rps, int num) { int i; -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America) Inc. 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