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Fri, 22 Oct 2021 11:14:00 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0025.hostedemail.com [216.40.44.25]) by kanga.kvack.org (Postfix) with ESMTP id 5FA22900003 for ; Fri, 22 Oct 2021 11:14:00 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 197CA18028502 for ; Fri, 22 Oct 2021 15:14:00 +0000 (UTC) X-FDA: 78724418640.06.3DC2580 Received: from mail-io1-f51.google.com (mail-io1-f51.google.com [209.85.166.51]) by imf19.hostedemail.com (Postfix) with ESMTP id 55346B0000A3 for ; Fri, 22 Oct 2021 15:13:56 +0000 (UTC) Received: by mail-io1-f51.google.com with SMTP id z69so5782574iof.9 for ; Fri, 22 Oct 2021 08:13:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=H4h6zM7XNDOt/0t7bVoQdTbpuZEiJ2tlFj3HfvQMOck=; b=gRgu5hw35yWVL9m4evJJtKQuOh4sINuCNMB8NgoM9qq+BCHMDM7b7Tq9HlTvpO81fO 8D6hZQUVIWKNPcPR1+SlQJDxt+CifHdLSt5LN27JjGS4y2HNkK2xYHvwu9qCWjnFy80y Av2zEZ4eJZd7LMf4kfeJ9zJULLDqMckewM6lLgVNrhMS0WOLqt224dLbkP7NdFtJAfR4 wTjLDrskHRGsAjPTJ/Y7BzowXDGy+0FIInAazSt5i3xbVRYxckzif2zXTDq1dUzskRrI y2dnBDAjRDChnPMiZABaYL2YGyL8QuseHZJywRTBG5DCxCtq1vqw5c2aaCFspedoKVyE XlLw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=H4h6zM7XNDOt/0t7bVoQdTbpuZEiJ2tlFj3HfvQMOck=; b=ryyZst6Ibc+DWHEPHIEZm6W3cfQbX2FIO7DmIwE7qPhvY88U8WGcgOboiJaPCW+lji 49sSz0LS5UzPGJoYlNAqGMFknPXjnuJdD53plcz5vTAvk49SwNNNAcPs4Q5Oe0adDfWz Xz7aSSVAsuLm6kM4vSDoAJUdIK3H/XPSFf+dISAsHQR4QUUXJ8XlKOX2bUYWmLrDfAH7 ZzZZaAQ9vZ+ykp2lZvQo2h/D4dZ5zApoG4Octzz/b91Kj3QS+pfFFDHEgKeGjUfnr/Vu 7cngZJAU9HiA3ouMLbsLO8lagy47oLTuj/rmnjvomJxTlwhBtcxphagzMxajy3pinpah 78kQ== X-Gm-Message-State: AOAM531nuHEa2guQuH+0HkAA2hOYGZ4Pb4cKs3agH0Tm3UMMDh8YLSpV nmwnyboCuZZXJzSSwYK09ff0/syl5CWByhbjFH0= X-Google-Smtp-Source: ABdhPJwOAuHHsTDH9XxnqN2WkdKQQckJ40UvB+cCk/ZjD6QPBL19lD3Zm9jyXnxOECLoQEaGeAgQWHYb3r50fX3a7Kk= X-Received: by 2002:a05:6602:27d4:: with SMTP id l20mr137826ios.94.1634915639269; Fri, 22 Oct 2021 08:13:59 -0700 (PDT) MIME-Version: 1.0 References: <20211019142621.2810043-1-willy@infradead.org> <20211019142621.2810043-5-willy@infradead.org> In-Reply-To: <20211019142621.2810043-5-willy@infradead.org> From: Yafang Shao Date: Fri, 22 Oct 2021 23:13:23 +0800 Message-ID: Subject: Re: [PATCH v2 4/5] test_printf: Append strings more efficiently To: "Matthew Wilcox (Oracle)" Cc: Sergey Senozhatsky , Petr Mladek , Linux MM , Vlastimil Babka , Rasmus Villemoes Content-Type: text/plain; charset="UTF-8" X-Rspamd-Server: rspam02 X-Rspamd-Queue-Id: 55346B0000A3 X-Stat-Signature: tqjy5jre584phthho17fnz4uuix8k5m8 Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=gmail.com header.s=20210112 header.b=gRgu5hw3; dmarc=pass (policy=none) header.from=gmail.com; spf=pass (imf19.hostedemail.com: domain of laoar.shao@gmail.com designates 209.85.166.51 as permitted sender) smtp.mailfrom=laoar.shao@gmail.com X-HE-Tag: 1634915636-963337 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Tue, Oct 19, 2021 at 10:33 PM Matthew Wilcox (Oracle) wrote: > > Use scnprintf instead of snprintf + strlen. > > Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: Yafang Shao > --- > lib/test_printf.c | 18 +++++++----------- > 1 file changed, 7 insertions(+), 11 deletions(-) > > diff --git a/lib/test_printf.c b/lib/test_printf.c > index ec584196cb99..d09993fca463 100644 > --- a/lib/test_printf.c > +++ b/lib/test_printf.c > @@ -614,8 +614,7 @@ page_flags_test(int section, int node, int zone, int last_cpupid, > int i; > > if (flags & PAGEFLAGS_MASK) { > - snprintf(cmp_buf + size, BUF_SIZE - size, "%s", name); > - size = strlen(cmp_buf); > + size += scnprintf(cmp_buf + size, BUF_SIZE - size, "%s", name); > append = true; > } > > @@ -623,17 +622,14 @@ page_flags_test(int section, int node, int zone, int last_cpupid, > if (!pft[i].width) > continue; > > - if (append) { > - snprintf(cmp_buf + size, BUF_SIZE - size, "|"); > - size = strlen(cmp_buf); > - } > + if (append) > + size += scnprintf(cmp_buf + size, BUF_SIZE - size, "|"); > > flags |= (values[i] & pft[i].mask) << pft[i].shift; > - snprintf(cmp_buf + size, BUF_SIZE - size, "%s=", pft[i].name); > - size = strlen(cmp_buf); > - snprintf(cmp_buf + size, BUF_SIZE - size, pft[i].fmt, > - values[i] & pft[i].mask); > - size = strlen(cmp_buf); > + size += scnprintf(cmp_buf + size, BUF_SIZE - size, "%s=", > + pft[i].name); > + size += scnprintf(cmp_buf + size, BUF_SIZE - size, pft[i].fmt, > + values[i] & pft[i].mask); > append = true; > } > > -- > 2.32.0 > -- Thanks Yafang