From patchwork Wed Jan 7 07:35:56 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wang Nan X-Patchwork-Id: 5583081 Return-Path: X-Original-To: patchwork-linux-arm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 7649EBF6C3 for ; Wed, 7 Jan 2015 07:55:06 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 7F3A62025B for ; Wed, 7 Jan 2015 07:55:05 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher DHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8FB2120256 for ; Wed, 7 Jan 2015 07:55:04 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1Y8lPN-0004cM-Dz; Wed, 07 Jan 2015 07:52:01 +0000 Received: from szxga01-in.huawei.com ([119.145.14.64]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Y8lFe-0004ET-1z for linux-arm-kernel@lists.infradead.org; Wed, 07 Jan 2015 07:41:59 +0000 Received: from 172.24.2.119 (EHLO lggeml422-hub.china.huawei.com) ([172.24.2.119]) by szxrg01-dlp.huawei.com (MOS 4.3.7-GA FastPath queued) with ESMTP id CHD59519; Wed, 07 Jan 2015 15:41:09 +0800 (CST) Received: from kernel-host.huawei (10.107.197.247) by lggeml422-hub.china.huawei.com (10.72.61.32) with Microsoft SMTP Server id 14.3.158.1; Wed, 7 Jan 2015 15:40:57 +0800 From: Wang Nan To: , , , , , , , , Subject: [RFC PATCH 08/11] kprobes: allows __alloc_insn_slot() from early kprobes slots. Date: Wed, 7 Jan 2015 15:35:56 +0800 Message-ID: <1420616156-43066-1-git-send-email-wangnan0@huawei.com> X-Mailer: git-send-email 1.8.4 In-Reply-To: <1420616086-42692-1-git-send-email-wangnan0@huawei.com> References: <1420616086-42692-1-git-send-email-wangnan0@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.107.197.247] X-CFilter-Loop: Reflected X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20150106_234158_702868_85C108DE X-CRM114-Status: UNSURE ( 9.80 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -0.7 (/) Cc: lizefan@huawei.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Spam-Status: No, score=-4.2 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_MED, T_RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Introduces early_slots_start/end and bitmap for struct kprobe_insn_cache then uses previous introduced macro to generate allocator. This patch makes get/free_insn_slot() and get/free_optinsn_slot() transparent to early kprobes. Signed-off-by: Wang Nan --- include/linux/kprobes.h | 33 +++++++++++++++++++++++++++++++++ kernel/kprobes.c | 14 ++++++++++++++ 2 files changed, 47 insertions(+) diff --git a/include/linux/kprobes.h b/include/linux/kprobes.h index 9a18188..27a27ed 100644 --- a/include/linux/kprobes.h +++ b/include/linux/kprobes.h @@ -316,6 +316,10 @@ static inline int ek_free_##__name(__t *__s) \ (__ek_##__name##_bitmap)); \ } +extern kprobe_opcode_t __early_kprobes_code_area_start[]; +extern kprobe_opcode_t __early_kprobes_code_area_end[]; +extern kprobe_opcode_t __early_kprobes_insn_slot_start[]; +extern kprobe_opcode_t __early_kprobes_insn_slot_end[]; #else #define __DEFINE_EKPROBE_ALLOC_OPS(__t, __name) \ @@ -339,6 +343,8 @@ static inline void ek_free_##__name(__t *__s) \ #endif +__DEFINE_EKPROBE_ALLOC_OPS(kprobe_opcode_t, opcode) + struct kprobe_insn_cache { struct mutex mutex; void *(*alloc)(void); /* allocate insn page */ @@ -346,8 +352,35 @@ struct kprobe_insn_cache { struct list_head pages; /* list of kprobe_insn_page */ size_t insn_size; /* size of instruction slot */ int nr_garbage; +#ifdef CONFIG_EARLY_KPROBES +# define slots_start(c) ((c)->early_slots_start) +# define slots_end(c) ((c)->early_slots_end) +# define slots_bitmap(c) ((c)->early_slots_bitmap) + kprobe_opcode_t *early_slots_start; + kprobe_opcode_t *early_slots_end; + unsigned long early_slots_bitmap[EARLY_KPROBES_BITMAP_SZ]; +#else +# define slots_start(c) NULL +# define slots_end(c) NULL +# define slots_bitmap(c) NULL +#endif }; +static inline kprobe_opcode_t * +__get_insn_slot_early(struct kprobe_insn_cache *c) +{ + return __ek_alloc_opcode(slots_start(c), + slots_end(c), slots_bitmap(c)); +} + +static inline int +__free_insn_slot_early(struct kprobe_insn_cache *c, + kprobe_opcode_t *slot) +{ + return __ek_free_opcode(slot, slots_start(c), + slots_end(c), slots_bitmap(c)); +} + extern kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c); extern void __free_insn_slot(struct kprobe_insn_cache *c, kprobe_opcode_t *slot, int dirty); diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 4591cae..1882bfa 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -137,6 +137,10 @@ struct kprobe_insn_cache kprobe_insn_slots = { .pages = LIST_HEAD_INIT(kprobe_insn_slots.pages), .insn_size = MAX_INSN_SIZE, .nr_garbage = 0, +#ifdef CONFIG_EARLY_KPROBES + .early_slots_start = __early_kprobes_insn_slot_start, + .early_slots_end = __early_kprobes_insn_slot_end, +#endif }; static int collect_garbage_slots(struct kprobe_insn_cache *c); @@ -149,6 +153,9 @@ kprobe_opcode_t *__get_insn_slot(struct kprobe_insn_cache *c) struct kprobe_insn_page *kip; kprobe_opcode_t *slot = NULL; + if (unlikely(!kprobes_initialized)) + return __get_insn_slot_early(c); + mutex_lock(&c->mutex); retry: list_for_each_entry(kip, &c->pages, list) { @@ -249,6 +256,9 @@ void __free_insn_slot(struct kprobe_insn_cache *c, { struct kprobe_insn_page *kip; + if (unlikely(__free_insn_slot_early(c, slot))) + return; + mutex_lock(&c->mutex); list_for_each_entry(kip, &c->pages, list) { long idx = ((long)slot - (long)kip->insns) / @@ -280,6 +290,10 @@ struct kprobe_insn_cache kprobe_optinsn_slots = { .pages = LIST_HEAD_INIT(kprobe_optinsn_slots.pages), /* .insn_size is initialized later */ .nr_garbage = 0, +#ifdef CONFIG_EARLY_KPROBES + .early_slots_start = __early_kprobes_code_area_start, + .early_slots_end = __early_kprobes_code_area_end, +#endif }; #endif #endif