From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 619951FB7 for ; Fri, 25 Mar 2022 01:10:35 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2B035C340EC; Fri, 25 Mar 2022 01:10:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1648170635; bh=03ssD2oDVYq3aYa6nAqrqD/sSjXum6w+GSmNj+fRUNY=; h=Date:To:From:In-Reply-To:Subject:From; b=ihH5v3E8wlPDKA2TxzM1YBbQLH1+jRUCiL8F3BScZKxbw1XEuSgClYM+b76v9CuNN DqCWdX++FW/YTqyYBU9R/nKGW1Fn2VTa7po/UuCIDVEJWuyhgylkVrMKm3gz/KUhW5 GOOv6G1AffwYKBEeMUPBeMouIPD+N9GEeHfdOxmY= Date: Thu, 24 Mar 2022 18:10:34 -0700 To: will@kernel.org,vincenzo.frascino@arm.com,ryabinin.a.a@gmail.com,pcc@google.com,mark.rutland@arm.com,glider@google.com,eugenis@google.com,elver@google.com,dvyukov@google.com,catalin.marinas@arm.com,andreyknvl@google.com,akpm@linux-foundation.org,patches@lists.linux.dev,linux-mm@kvack.org,mm-commits@vger.kernel.org,torvalds@linux-foundation.org,akpm@linux-foundation.org From: Andrew Morton In-Reply-To: <20220324180758.96b1ac7e17675d6bc474485e@linux-foundation.org> Subject: [patch 040/114] kasan, page_alloc: combine tag_clear_highpage calls in post_alloc_hook Message-Id: <20220325011035.2B035C340EC@smtp.kernel.org> Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: From: Andrey Konovalov Subject: kasan, page_alloc: combine tag_clear_highpage calls in post_alloc_hook Move tag_clear_highpage() loops out of the kasan_has_integrated_init() clause as a code simplification. This patch does no functional changes. Link: https://lkml.kernel.org/r/587e3fc36358b88049320a89cc8dc6deaecb0cda.1643047180.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Reviewed-by: Alexander Potapenko Acked-by: Marco Elver Cc: Andrey Ryabinin Cc: Catalin Marinas Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Mark Rutland Cc: Peter Collingbourne Cc: Vincenzo Frascino Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/page_alloc.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) --- a/mm/page_alloc.c~kasan-page_alloc-combine-tag_clear_highpage-calls-in-post_alloc_hook +++ a/mm/page_alloc.c @@ -2367,30 +2367,30 @@ inline void post_alloc_hook(struct page * KASAN unpoisoning and memory initializion code must be * kept together to avoid discrepancies in behavior. */ + + /* + * If memory tags should be zeroed (which happens only when memory + * should be initialized as well). + */ + if (init_tags) { + int i; + + /* Initialize both memory and tags. */ + for (i = 0; i != 1 << order; ++i) + tag_clear_highpage(page + i); + + /* Note that memory is already initialized by the loop above. */ + init = false; + } if (kasan_has_integrated_init()) { if (gfp_flags & __GFP_SKIP_KASAN_POISON) SetPageSkipKASanPoison(page); - if (init_tags) { - int i; - - for (i = 0; i != 1 << order; ++i) - tag_clear_highpage(page + i); - } else { + if (!init_tags) kasan_unpoison_pages(page, order, init); - } } else { kasan_unpoison_pages(page, order, init); - if (init_tags) { - int i; - - for (i = 0; i < 1 << order; i++) - tag_clear_highpage(page + i); - - init = false; - } - if (init) kernel_init_free_pages(page, 1 << order); } _