From patchwork Fri Sep 8 13:39:20 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13377480 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 856F65254 for ; Fri, 8 Sep 2023 13:39:39 +0000 (UTC) Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 376A919BC for ; Fri, 8 Sep 2023 06:39:37 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Rhxzk0VS2z4f3knY for ; Fri, 8 Sep 2023 21:39:30 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDHVqkPJPtkRmSwCg--.44307S5; Fri, 08 Sep 2023 21:39:33 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , houtao1@huawei.com Subject: [PATCH bpf 1/4] bpf: Adjust size_index according to the value of KMALLOC_MIN_SIZE Date: Fri, 8 Sep 2023 21:39:20 +0800 Message-Id: <20230908133923.2675053-2-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20230908133923.2675053-1-houtao@huaweicloud.com> References: <20230908133923.2675053-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDHVqkPJPtkRmSwCg--.44307S5 X-Coremail-Antispam: 1UD129KBjvJXoW3Jr17Cr18Jr4DKFW8AF4rAFb_yoW7Xr1kpF y3Jr18Gr48ZF4xJr47CF4rJFWrGw1Fk3W7JrWfXw1UZF15Gr1DJr1ktryruFyqqrWrZ3W7 JF4qqw48Kr1UJaDanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9Eb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUGw A2048vs2IY020Ec7CjxVAFwI0_Gr0_Xr1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW8JVW5JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV W8JVWxJwA2z4x0Y4vEx4A2jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0 oVCq3wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv7V C0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r1j 6r4UM4x0Y48IcxkI7VAKI48JM4IIrI8v6xkF7I0E8cxan2IY04v7MxAIw28IcxkI7VAKI4 8JMxC20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xv wVAFwI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjx v20xvE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20E Y4v20xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267 AKxVW8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7IU8-TmDUUUUU== X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_MSPIKE_H2, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao The following warning was reported when running "./test_progs -a link_api -a linked_list" on a RISC-V QEMU VM: ------------[ cut here ]------------ WARNING: CPU: 3 PID: 261 at kernel/bpf/memalloc.c:342 bpf_mem_refill Modules linked in: bpf_testmod(OE) CPU: 3 PID: 261 Comm: test_progs- ... 6.5.0-rc5-01743-gdcb152bb8328 #2 Hardware name: riscv-virtio,qemu (DT) epc : bpf_mem_refill+0x1fc/0x206 ra : irq_work_single+0x68/0x70 epc : ffffffff801b1bc4 ra : ffffffff8015fe84 sp : ff2000000001be20 gp : ffffffff82d26138 tp : ff6000008477a800 t0 : 0000000000046600 t1 : ffffffff812b6ddc t2 : 0000000000000000 s0 : ff2000000001be70 s1 : ff5ffffffffe8998 a0 : ff5ffffffffe8998 a1 : ff600003fef4b000 a2 : 000000000000003f a3 : ffffffff80008250 a4 : 0000000000000060 a5 : 0000000000000080 a6 : 0000000000000000 a7 : 0000000000735049 s2 : ff5ffffffffe8998 s3 : 0000000000000022 s4 : 0000000000001000 s5 : 0000000000000007 s6 : ff5ffffffffe8570 s7 : ffffffff82d6bd30 s8 : 000000000000003f s9 : ffffffff82d2c5e8 s10: 000000000000ffff s11: ffffffff82d2c5d8 t3 : ffffffff81ea8f28 t4 : 0000000000000000 t5 : ff6000008fd28278 t6 : 0000000000040000 [] bpf_mem_refill+0x1fc/0x206 [] irq_work_single+0x68/0x70 [] irq_work_run_list+0x28/0x36 [] irq_work_run+0x38/0x66 [] handle_IPI+0x3a/0xb4 [] handle_percpu_devid_irq+0xa4/0x1f8 [] generic_handle_domain_irq+0x28/0x36 [] ipi_mux_process+0xac/0xfa [] sbi_ipi_handle+0x2e/0x88 [] generic_handle_domain_irq+0x28/0x36 [] riscv_intc_irq+0x36/0x4e [] handle_riscv_irq+0x54/0x86 [] do_irq+0x66/0x98 ---[ end trace 0000000000000000 ]--- The warning is due to WARN_ON_ONCE(tgt->unit_size != c->unit_size) in free_bulk(). The direct reason is that a object is allocated and freed by bpf_mem_caches with different unit_size. The root cause is that KMALLOC_MIN_SIZE is 64 and there is no 96-bytes slab cache in the specific VM. When linked_list test allocates a 72-bytes object through bpf_obj_new(), bpf_global_ma will allocate it from a bpf_mem_cache with 96-bytes unit_size, but this bpf_mem_cache is backed by 128-bytes slab cache. When the object is freed, bpf_mem_free() uses ksize() to choose the corresponding bpf_mem_cache. Because the object is allocated from 128-bytes slab cache, ksize() returns 128, bpf_mem_free() chooses a 128-bytes bpf_mem_cache to free the object and triggers the warning. A similar warning will also be reported when using CONFIG_SLAB instead of CONFIG_SLUB in a x86-64 kernel. Because CONFIG_SLUB defines KMALLOC_MIN_SIZE as 8 but CONFIG_SLAB defines KMALLOC_MIN_SIZE as 32. An alternative fix is to use kmalloc_size_round() in bpf_mem_alloc() to choose a bpf_mem_cache which has the same unit_size with the backing slab cache, but it may introduce performance degradation, so fix the warning by adjusting the indexes in size_index according to the value of KMALLOC_MIN_SIZE just like setup_kmalloc_cache_index_table() does. Fixes: 822fb26bdb55 ("bpf: Add a hint to allocated objects.") Reported-by: Björn Töpel Closes: https://lore.kernel.org/bpf/87jztjmmy4.fsf@all.your.base.are.belong.to.us Signed-off-by: Hou Tao --- kernel/bpf/memalloc.c | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 9c49ae53deaf..98d9e96fba3c 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -916,3 +916,41 @@ void notrace *bpf_mem_cache_alloc_flags(struct bpf_mem_alloc *ma, gfp_t flags) return !ret ? NULL : ret + LLIST_NODE_SZ; } + +/* Most of the logic is taken from setup_kmalloc_cache_index_table() */ +static __init int bpf_mem_cache_adjust_size(void) +{ + unsigned int size, index; + + /* Normally KMALLOC_MIN_SIZE is 8-bytes, but it can be + * up-to 256-bytes. + */ + size = KMALLOC_MIN_SIZE; + if (size <= 192) + index = size_index[(size - 1) / 8]; + else + index = fls(size - 1) - 1; + for (size = 8; size < KMALLOC_MIN_SIZE && size <= 192; size += 8) + size_index[(size - 1) / 8] = index; + + /* The minimal alignment is 64-bytes, so disable 96-bytes cache and + * use 128-bytes cache instead. + */ + if (KMALLOC_MIN_SIZE >= 64) { + index = size_index[(128 - 1) / 8]; + for (size = 64 + 8; size <= 96; size += 8) + size_index[(size - 1) / 8] = index; + } + + /* The minimal alignment is 128-bytes, so disable 192-bytes cache and + * use 256-bytes cache instead. + */ + if (KMALLOC_MIN_SIZE >= 128) { + index = fls(256 - 1) - 1; + for (size = 128 + 8; size <= 192; size += 8) + size_index[(size - 1) / 8] = index; + } + + return 0; +} +subsys_initcall(bpf_mem_cache_adjust_size); From patchwork Fri Sep 8 13:39:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13377482 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 22CE563B3 for ; Fri, 8 Sep 2023 13:39:39 +0000 (UTC) Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B2B1A1BC5 for ; Fri, 8 Sep 2023 06:39:37 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4Rhxzn6PN0z4f3kpV for ; Fri, 8 Sep 2023 21:39:33 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDHVqkPJPtkRmSwCg--.44307S6; Fri, 08 Sep 2023 21:39:34 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , houtao1@huawei.com Subject: [PATCH bpf 2/4] bpf: Don't prefill for unused bpf_mem_cache Date: Fri, 8 Sep 2023 21:39:21 +0800 Message-Id: <20230908133923.2675053-3-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20230908133923.2675053-1-houtao@huaweicloud.com> References: <20230908133923.2675053-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDHVqkPJPtkRmSwCg--.44307S6 X-Coremail-Antispam: 1UD129KBjvJXoW7CF45Zw4rZFW3AFW5JFy8AFb_yoW8tryxpF y3CF10krs5ZFZru3WxWw1xCayft34vg3Zrt3yrtry09rs5ur1Dur4DJry7XFyY9rZ7ta1f Ar4kKry0gF4UZFJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBjb4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUXw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx 0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWU JVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04k2 6cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7CjxV AFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x07UC9aPUUUUU= X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,KHOP_HELO_FCRDNS, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao When the unit_size of a bpf_mem_cache is unmatched with the object_size of the underlying slab cache, the bpf_mem_cache will not be used, and the allocation will be redirected to a bpf_mem_cache with a bigger unit_size instead, so there is no need to prefill for these unused bpf_mem_caches. Signed-off-by: Hou Tao --- kernel/bpf/memalloc.c | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 98d9e96fba3c..90c1ed8210a2 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -459,8 +459,7 @@ static void notrace irq_work_raise(struct bpf_mem_cache *c) * Typical case will be between 11K and 116K closer to 11K. * bpf progs can and should share bpf_mem_cache when possible. */ - -static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) +static void init_refill_work(struct bpf_mem_cache *c) { init_irq_work(&c->refill_work, bpf_mem_refill); if (c->unit_size <= 256) { @@ -476,7 +475,10 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) c->high_watermark = max(96 * 256 / c->unit_size, 3); } c->batch = max((c->high_watermark - c->low_watermark) / 4 * 3, 1); +} +static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) +{ /* To avoid consuming memory assume that 1st run of bpf * prog won't be doing more than 4 map_update_elem from * irq disabled region @@ -521,6 +523,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) c->objcg = objcg; c->percpu_size = percpu_size; c->tgt = c; + init_refill_work(c); prefill_mem_cache(c, cpu); } ma->cache = pc; @@ -544,6 +547,15 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) c->unit_size = sizes[i]; c->objcg = objcg; c->tgt = c; + + init_refill_work(c); + /* Another bpf_mem_cache will be used when allocating + * c->unit_size in bpf_mem_alloc(), so doesn't prefill + * for the bpf_mem_cache because these free objects will + * never be used. + */ + if (i != bpf_mem_cache_idx(c->unit_size)) + continue; prefill_mem_cache(c, cpu); } } From patchwork Fri Sep 8 13:39:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13377483 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 76DAE63C9 for ; Fri, 8 Sep 2023 13:39:40 +0000 (UTC) Received: from dggsgout12.his.huawei.com (dggsgout12.his.huawei.com [45.249.212.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id CDE3B1BEA for ; Fri, 8 Sep 2023 06:39:37 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout12.his.huawei.com (SkyGuard) with ESMTP id 4Rhxzl1P2Nz4f3l7b for ; Fri, 8 Sep 2023 21:39:31 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDHVqkPJPtkRmSwCg--.44307S7; Fri, 08 Sep 2023 21:39:34 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , houtao1@huawei.com Subject: [PATCH bpf 3/4] bpf: Ensure unit_size is matched with slab cache object size Date: Fri, 8 Sep 2023 21:39:22 +0800 Message-Id: <20230908133923.2675053-4-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20230908133923.2675053-1-houtao@huaweicloud.com> References: <20230908133923.2675053-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDHVqkPJPtkRmSwCg--.44307S7 X-Coremail-Antispam: 1UD129KBjvJXoWxCF48ur4fAFyUury3tFyxKrg_yoW5XFyfpF y7CF1rKrsYyFW7Wa1aqrs7Ca4ft340qF17J3yaq3409r4rXr1DGF4DJry2gF98urWrJa13 Jr1kKr40krWUArJanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUB0b4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUWw A2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxS w2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxV WxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_ GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx 0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWU JVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20xvY0x0EwI xGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E7480 Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0I7 IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE42xK 8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6xkF7I 0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUFYFCUUUUU X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RCVD_IN_MSPIKE_H2, SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Add extra check in bpf_mem_alloc_init() to ensure the unit_size of bpf_mem_cache is matched with the object_size of underlying slab cache. If these two sizes are unmatched, print a warning once and return -EINVAL in bpf_mem_alloc_init(), so the mismatch can be found early and the potential issue can be prevented. Suggested-by: Alexei Starovoitov Signed-off-by: Hou Tao Signed-off-by: Hou Tao --- kernel/bpf/memalloc.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 90c1ed8210a2..1c22b90e754a 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -486,6 +486,24 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) alloc_bulk(c, c->unit_size <= 256 ? 4 : 1, cpu_to_node(cpu), false); } +static int check_obj_size(struct bpf_mem_cache *c, unsigned int idx) +{ + struct llist_node *first; + unsigned int obj_size; + + first = c->free_llist.first; + if (!first) + return 0; + + obj_size = ksize(first); + if (obj_size != c->unit_size) { + WARN_ONCE(1, "bpf_mem_cache[%u]: unexpected object size %u, expect %u\n", + idx, obj_size, c->unit_size); + return -EINVAL; + } + return 0; +} + /* When size != 0 bpf_mem_cache for each cpu. * This is typical bpf hash map use case when all elements have equal size. * @@ -496,10 +514,10 @@ static void prefill_mem_cache(struct bpf_mem_cache *c, int cpu) int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) { static u16 sizes[NUM_CACHES] = {96, 192, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096}; + int cpu, i, err, unit_size, percpu_size = 0; struct bpf_mem_caches *cc, __percpu *pcc; struct bpf_mem_cache *c, __percpu *pc; struct obj_cgroup *objcg = NULL; - int cpu, i, unit_size, percpu_size = 0; if (size) { pc = __alloc_percpu_gfp(sizeof(*pc), 8, GFP_KERNEL); @@ -537,6 +555,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) pcc = __alloc_percpu_gfp(sizeof(*cc), 8, GFP_KERNEL); if (!pcc) return -ENOMEM; + err = 0; #ifdef CONFIG_MEMCG_KMEM objcg = get_obj_cgroup_from_current(); #endif @@ -557,10 +576,20 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) if (i != bpf_mem_cache_idx(c->unit_size)) continue; prefill_mem_cache(c, cpu); + err = check_obj_size(c, i); + if (err) + goto out; } } + +out: ma->caches = pcc; - return 0; + /* refill_work is either zeroed or initialized, so it is safe to + * call irq_work_sync(). + */ + if (err) + bpf_mem_alloc_destroy(ma); + return err; } static void drain_mem_cache(struct bpf_mem_cache *c) From patchwork Fri Sep 8 13:39:23 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hou Tao X-Patchwork-Id: 13377484 X-Patchwork-Delegate: bpf@iogearbox.net Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B0BC263DE for ; Fri, 8 Sep 2023 13:39:40 +0000 (UTC) Received: from dggsgout11.his.huawei.com (unknown [45.249.212.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 86D2C1BF4 for ; Fri, 8 Sep 2023 06:39:38 -0700 (PDT) Received: from mail02.huawei.com (unknown [172.30.67.143]) by dggsgout11.his.huawei.com (SkyGuard) with ESMTP id 4Rhxzp6rVpz4f3l83 for ; Fri, 8 Sep 2023 21:39:34 +0800 (CST) Received: from huaweicloud.com (unknown [10.175.124.27]) by APP4 (Coremail) with SMTP id gCh0CgDHVqkPJPtkRmSwCg--.44307S8; Fri, 08 Sep 2023 21:39:35 +0800 (CST) From: Hou Tao To: bpf@vger.kernel.org Cc: Martin KaFai Lau , Alexei Starovoitov , Andrii Nakryiko , Song Liu , Hao Luo , Yonghong Song , Daniel Borkmann , KP Singh , Stanislav Fomichev , Jiri Olsa , John Fastabend , =?utf-8?b?QmrDtnJuIFTDtnBlbA==?= , houtao1@huawei.com Subject: [PATCH bpf 4/4] selftests/bpf: Test all valid alloc sizes for bpf mem allocator Date: Fri, 8 Sep 2023 21:39:23 +0800 Message-Id: <20230908133923.2675053-5-houtao@huaweicloud.com> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20230908133923.2675053-1-houtao@huaweicloud.com> References: <20230908133923.2675053-1-houtao@huaweicloud.com> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: gCh0CgDHVqkPJPtkRmSwCg--.44307S8 X-Coremail-Antispam: 1UD129KBjvJXoW3Jw4fWryxCr4kWF4DAFy8AFb_yoW7ur1xpa 40yFyYyrWfXw1xuryS9w429F1rXFs5Zw15JryxWFyUZr1rtryxtr1kKFy8tF93trWvgr4r Aa4agFWfGrs7A3DanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUB2b4IE77IF4wAFF20E14v26rWj6s0DM7CY07I20VC2zVCF04k2 6cxKx2IYs7xG6rWj6s0DM7CIcVAFz4kK6r1j6r18M28IrcIa0xkI8VA2jI8067AKxVWUAV Cq3wA2048vs2IY020Ec7CjxVAFwI0_Xr0E3s1l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0 rcxSw2x7M28EF7xvwVC0I7IYx2IY67AKxVW5JVW7JwA2z4x0Y4vE2Ix0cI8IcVCY1x0267 AKxVWxJVW8Jr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAF wI0_GcCE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2 WlYx0E2Ix0cI8IcVAFwI0_Jr0_Jr4lYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkE bVWUJVW8JwACjcxG0xvY0x0EwIxGrwACI402YVCY1x02628vn2kIc2xKxwCF04k20xvY0x 0EwIxGrwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E 7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcV C0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Cr0_Gr1UMIIF0xvE 42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42IY6I8E87Iv6x kF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxUFgAwUUUUU X-CM-SenderInfo: xkrx3t3r6k3tpzhluzxrxghudrp/ X-CFilter-Loop: Reflected X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00,KHOP_HELO_FCRDNS, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net X-Patchwork-Delegate: bpf@iogearbox.net From: Hou Tao Add a test to test all possible and valid allocation size for bpf memory allocator. For each possible allocation size, the test uses the following two steps to test the alloc and free path: 1) allocate N (N > high_watermark) objects to trigger the refill executed in irq_work. 2) free N objects to trigger the freeing executed in irq_work. Signed-off-by: Hou Tao --- .../selftests/bpf/prog_tests/test_bpf_ma.c | 50 +++++++ .../testing/selftests/bpf/progs/test_bpf_ma.c | 123 ++++++++++++++++++ 2 files changed, 173 insertions(+) create mode 100644 tools/testing/selftests/bpf/prog_tests/test_bpf_ma.c create mode 100644 tools/testing/selftests/bpf/progs/test_bpf_ma.c diff --git a/tools/testing/selftests/bpf/prog_tests/test_bpf_ma.c b/tools/testing/selftests/bpf/prog_tests/test_bpf_ma.c new file mode 100644 index 000000000000..0cca4e8ae38e --- /dev/null +++ b/tools/testing/selftests/bpf/prog_tests/test_bpf_ma.c @@ -0,0 +1,50 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023. Huawei Technologies Co., Ltd */ +#define _GNU_SOURCE +#include +#include +#include +#include +#include + +#include "test_bpf_ma.skel.h" + +void test_test_bpf_ma(void) +{ + struct test_bpf_ma *skel; + struct btf *btf; + int i, err; + + skel = test_bpf_ma__open(); + if (!ASSERT_OK_PTR(skel, "open")) + return; + + btf = bpf_object__btf(skel->obj); + if (!ASSERT_OK_PTR(btf, "btf")) + goto out; + + for (i = 0; i < ARRAY_SIZE(skel->rodata->data_sizes); i++) { + char name[32]; + int id; + + snprintf(name, sizeof(name), "bin_data_%u", skel->rodata->data_sizes[i]); + id = btf__find_by_name_kind(btf, name, BTF_KIND_STRUCT); + if (!ASSERT_GT(id, 0, "bin_data")) + goto out; + skel->rodata->data_btf_ids[i] = id; + } + + err = test_bpf_ma__load(skel); + if (!ASSERT_OK(err, "load")) + goto out; + + err = test_bpf_ma__attach(skel); + if (!ASSERT_OK(err, "attach")) + goto out; + + skel->bss->pid = getpid(); + usleep(1); + ASSERT_OK(skel->bss->err, "test error"); +out: + test_bpf_ma__destroy(skel); +} diff --git a/tools/testing/selftests/bpf/progs/test_bpf_ma.c b/tools/testing/selftests/bpf/progs/test_bpf_ma.c new file mode 100644 index 000000000000..ecde41ae0fc8 --- /dev/null +++ b/tools/testing/selftests/bpf/progs/test_bpf_ma.c @@ -0,0 +1,123 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (C) 2023. Huawei Technologies Co., Ltd */ +#include +#include +#include + +#include "bpf_experimental.h" +#include "bpf_misc.h" + +#ifndef ARRAY_SIZE +#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) +#endif + +struct generic_map_value { + void *data; +}; + +char _license[] SEC("license") = "GPL"; + +const unsigned int data_sizes[] = {8, 16, 32, 64, 96, 128, 192, 256, 512, 1024, 2048, 4096}; +const volatile unsigned int data_btf_ids[ARRAY_SIZE(data_sizes)] = {}; + +int err = 0; +int pid = 0; + +#define DEFINE_ARRAY_WITH_KPTR(_size) \ + struct bin_data_##_size { \ + char data[_size - sizeof(void *)]; \ + }; \ + struct map_value_##_size { \ + struct bin_data_##_size __kptr * data; \ + /* To emit BTF info for bin_data_xx */ \ + struct bin_data_##_size not_used; \ + }; \ + struct { \ + __uint(type, BPF_MAP_TYPE_ARRAY); \ + __type(key, int); \ + __type(value, struct map_value_##_size); \ + __uint(max_entries, 128); \ + } array_##_size SEC(".maps"); + +static __always_inline void batch_alloc_free(struct bpf_map *map, unsigned int batch, + unsigned int idx) +{ + struct generic_map_value *value; + unsigned int i, key; + void *old, *new; + + for (i = 0; i < batch; i++) { + key = i; + value = bpf_map_lookup_elem(map, &key); + if (!value) { + err = 1; + return; + } + new = bpf_obj_new_impl(data_btf_ids[idx], NULL); + if (!new) { + err = 2; + return; + } + old = bpf_kptr_xchg(&value->data, new); + if (old) { + bpf_obj_drop(old); + err = 3; + return; + } + } + for (i = 0; i < batch; i++) { + key = i; + value = bpf_map_lookup_elem(map, &key); + if (!value) { + err = 4; + return; + } + old = bpf_kptr_xchg(&value->data, NULL); + if (!old) { + err = 5; + return; + } + bpf_obj_drop(old); + } +} + +#define CALL_BATCH_ALLOC_FREE(size, batch, idx) \ + batch_alloc_free((struct bpf_map *)(&array_##size), batch, idx) + +DEFINE_ARRAY_WITH_KPTR(8); +DEFINE_ARRAY_WITH_KPTR(16); +DEFINE_ARRAY_WITH_KPTR(32); +DEFINE_ARRAY_WITH_KPTR(64); +DEFINE_ARRAY_WITH_KPTR(96); +DEFINE_ARRAY_WITH_KPTR(128); +DEFINE_ARRAY_WITH_KPTR(192); +DEFINE_ARRAY_WITH_KPTR(256); +DEFINE_ARRAY_WITH_KPTR(512); +DEFINE_ARRAY_WITH_KPTR(1024); +DEFINE_ARRAY_WITH_KPTR(2048); +DEFINE_ARRAY_WITH_KPTR(4096); + +SEC("fentry/" SYS_PREFIX "sys_nanosleep") +int test_bpf_mem_alloc_free(void *ctx) +{ + if ((u32)bpf_get_current_pid_tgid() != pid) + return 0; + + /* Alloc 128 8-bytes objects in batch to trigger refilling, + * then free 128 8-bytes objects in batch to trigger freeing. + */ + CALL_BATCH_ALLOC_FREE(8, 128, 0); + CALL_BATCH_ALLOC_FREE(16, 128, 1); + CALL_BATCH_ALLOC_FREE(32, 128, 2); + CALL_BATCH_ALLOC_FREE(64, 128, 3); + CALL_BATCH_ALLOC_FREE(96, 128, 4); + CALL_BATCH_ALLOC_FREE(128, 128, 5); + CALL_BATCH_ALLOC_FREE(192, 128, 6); + CALL_BATCH_ALLOC_FREE(256, 128, 7); + CALL_BATCH_ALLOC_FREE(512, 64, 8); + CALL_BATCH_ALLOC_FREE(1024, 32, 9); + CALL_BATCH_ALLOC_FREE(2048, 16, 10); + CALL_BATCH_ALLOC_FREE(4096, 8, 11); + + return 0; +}