From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id AC8653951899 for ; Thu, 24 Sep 2020 00:46:53 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org AC8653951899 Received: from mail-qk1-f200.google.com (mail-qk1-f200.google.com [209.85.222.200]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-493-OimzivYhNmyEhY8w6vXGLQ-1; Wed, 23 Sep 2020 20:46:51 -0400 X-MC-Unique: OimzivYhNmyEhY8w6vXGLQ-1 Received: by mail-qk1-f200.google.com with SMTP id j5so958378qka.7 for ; Wed, 23 Sep 2020 17:46:50 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:references:from:organization :message-id:date:user-agent:mime-version:in-reply-to :content-language:content-transfer-encoding; bh=Q7gtkpov2NZ49GPHCRdBQzuepUJMkAO7vOtcGixj+Hk=; b=Ng1tN/RzSfGJolM7769whUXIdYHg2+CrFyYs+W1lKQVZEfrqJXlTEAE7FC8IfNlE03 3EOjAMIstPgeZfnbQqid3vBwnFPEMBP8sdul2Fxsn9cfwKKUJ/sCp5HgXLw51evJeLtn T7xbfWBJV7J+n39k7/e8Saj3//UGPJaWdhDw4UPMyxRYdFLkVwMFONjHft8/ntF5YfkZ sKwOqDxXcsy2dEIoz5oYrjgZ9A933Cj8SjJJT0RuN92UVRw2imxT4jvWZJz/OSEHVc/1 FoN44pf1YY4/1QhG14BMsZnBfD0rLUFodAiO8bkQ4KlxNVWdWPGnX6wzj8M6VXL+Kq4d W5RA== X-Gm-Message-State: AOAM533GK8fotsSAMcMhW4ZhmpXyLNrtdiGuWqtwSsgk40vUbILqmgah G/z5oIqfTTRO9cpAW8dcNY4jeRXx9IP/pbWiqn+uRbrtTmdpgfZlM0Gs4R+/6LMrz0u5bok60j9 oeuBX5z2wY+qDdWOtI0O3 X-Received: by 2002:a37:9d4d:: with SMTP id g74mr2473004qke.422.1600908409794; Wed, 23 Sep 2020 17:46:49 -0700 (PDT) X-Google-Smtp-Source: ABdhPJxtEHkuOdt3LOQye5wKQhJd/E+7FzDmE7pjyl94MHQQDS9p5EXgmxA2Rs2Fbiemqf0Aho0Q5g== X-Received: by 2002:a37:9d4d:: with SMTP id g74mr2472986qke.422.1600908409413; Wed, 23 Sep 2020 17:46:49 -0700 (PDT) Received: from [192.168.1.16] (198-84-214-74.cpe.teksavvy.com. [198.84.214.74]) by smtp.gmail.com with ESMTPSA id p187sm1031424qkd.129.2020.09.23.17.46.48 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 23 Sep 2020 17:46:48 -0700 (PDT) Subject: Re: [PATCH 3/4] bench-strncmp.c: Add workloads on page boundary To: "H.J. Lu" , libc-alpha@sourceware.org References: <20200612201056.228614-1-hjl.tools@gmail.com> <20200612201056.228614-3-hjl.tools@gmail.com> From: Carlos O'Donell Organization: Red Hat Message-ID: Date: Wed, 23 Sep 2020 20:46:47 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.11.0 MIME-Version: 1.0 In-Reply-To: <20200612201056.228614-3-hjl.tools@gmail.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-Spam-Status: No, score=-11.5 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, NICE_REPLY_A, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H5, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Sep 2020 00:46:55 -0000 On 6/12/20 4:10 PM, H.J. Lu via Libc-alpha wrote: > Add strncmp workloads on page boundary. This benchmark need some work. Please post v2. > --- > benchtests/bench-strncmp.c | 117 +++++++++++++++++++++++++++++++++++++ > 1 file changed, 117 insertions(+) > > diff --git a/benchtests/bench-strncmp.c b/benchtests/bench-strncmp.c > index 95a59c9465..065c7e7789 100644 > --- a/benchtests/bench-strncmp.c > +++ b/benchtests/bench-strncmp.c > @@ -27,6 +27,7 @@ > > #ifdef WIDE > # define L(str) L##str > +# define STRDUP wcsdup OK. > # define SIMPLE_STRNCMP simple_wcsncmp > > /* Wcsncmp uses signed semantics for comparison, not unsigned. > @@ -48,6 +49,7 @@ simple_wcsncmp (const CHAR *s1, const CHAR *s2, size_t n) > > #else > # define L(str) str > +# define STRDUP strdup OK. > # define SIMPLE_STRNCMP simple_strncmp > > /* Strncmp uses unsigned semantics for comparison. */ > @@ -190,6 +192,118 @@ do_test (json_ctx_t *json_ctx, size_t align1, size_t align2, size_t len, size_t > json_element_object_end (json_ctx); > } > > +static void > +do_test_page_boundary_1 (json_ctx_t *json_ctx, CHAR *s1, CHAR *s2, Rename to "do_one_test_page_boundary" > + size_t align1, size_t align2, size_t len, > + size_t n, int exp_result) > +{ > + json_element_object_begin (json_ctx); > + json_attr_uint (json_ctx, "strlen", (double) len); > + json_attr_uint (json_ctx, "len", (double) n); > + json_attr_uint (json_ctx, "align1", (double) align1); > + json_attr_uint (json_ctx, "align2", (double) align2); > + json_array_begin (json_ctx, "timings"); > + FOR_EACH_IMPL (impl, 0) > + do_one_test (json_ctx, impl, s1, s2, n, exp_result); > + json_array_end (json_ctx); > + json_element_object_end (json_ctx); OK. > +} > + Add a comment: /* To trigger bug 25933 we need a size that is equal to the vector length times 4. In the case of AVX2 for Intel we need 32 * 4. We make this test generic and run it for all architectures as additional boundary testing for such related algorithms. */ > +static void > +do_test_page_boundary (json_ctx_t *json_ctx) OK. > +{ > + size_t size = 32 * 4; > + size_t len; > + CHAR *s1 = (CHAR *) (buf1 + (BUF1PAGES - 1) * page_size); > + CHAR *s2 = (CHAR *) (buf2 + (BUF1PAGES - 1) * page_size); > + int exp_result; > + > + memset (s1, 'a', page_size); > + memset (s2, 'a', page_size); > + > + s1[(page_size / CHARBYTES) - 1] = (CHAR) 0; > + Add comment: /* Iterate over a size that is just below where we expect the bug to trigger up to the size we expect will trigger the bug e.g. [99-128]. Likewise iterate the start of two strings between 30 and 31 bytes away from the boundary to simulate alignment changes. */ > + for (size_t s = 99; s <= size; s++) > + for (size_t s1a = 31; s1a < 32; s1a++) Please make s1a iterate over [30,32) like s2a. > + for (size_t s2a = 30; s2a < 32; s2a++) > + { > + size_t align1 = (page_size / CHARBYTES - s) - s1a; > + size_t align2 = (page_size / CHARBYTES - s) - s2a; > + CHAR *s1p = s1 + align1; > + CHAR *s2p = s2 + align2; > + len = (page_size / CHARBYTES) - 1 - align1; > + exp_result = SIMPLE_STRNCMP (s1p, s2p, s); > + do_test_page_boundary_1 (json_ctx, s1p, s2p, align1, align2, > + len, s, exp_result); > + } > +} > + > +static void > +do_page_test (json_ctx_t *json_ctx, size_t offset1, size_t offset2, Rename to do_one_test_page() > + CHAR *s2) > +{ > + CHAR *s1; > + int exp_result; > + > + if (offset1 * CHARBYTES >= page_size > + || offset2 * CHARBYTES >= page_size) > + return; OK. Nothing bigger than a page size because we only have one page to work within. > + > + s1 = (CHAR *) buf1; > + s1 += offset1; > + s2 += offset2; > + > + size_t len = (page_size / CHARBYTES) - offset1; > + > + exp_result= *s1; > + > + json_element_object_begin (json_ctx); > + json_attr_uint (json_ctx, "strlen", (double) len); > + json_attr_uint (json_ctx, "len", (double) page_size); > + json_attr_uint (json_ctx, "align1", (double) offset1); > + json_attr_uint (json_ctx, "align2", (double) offset2); > + json_array_begin (json_ctx, "timings"); > + { > + FOR_EACH_IMPL (impl, 0) > + do_one_test (json_ctx, impl, s1, s2, page_size, -exp_result); > + } > + json_array_end (json_ctx); > + json_element_object_end (json_ctx); > + > + json_element_object_begin (json_ctx); > + json_attr_uint (json_ctx, "strlen", (double) len); > + json_attr_uint (json_ctx, "len", (double) page_size); > + json_attr_uint (json_ctx, "align1", (double) offset1); > + json_attr_uint (json_ctx, "align2", (double) offset2); > + json_array_begin (json_ctx, "timings"); > + { > + FOR_EACH_IMPL (impl, 0) > + do_one_test (json_ctx, impl, s1, s2, page_size, exp_result); > + } > + json_array_end (json_ctx); > + json_element_object_end (json_ctx); > +} OK. > + > +static void > +do_test_page (json_ctx_t *json_ctx) > +{ > + size_t i; > + CHAR *s1, *s2; > + > + s1 = (CHAR *) buf1; > + for (i = 0; i < (page_size / CHARBYTES) - 1; i++) > + s1[i] = 23; Add a comment for this magic fill number. > + s1[i] = 0; > + > + s2 = STRDUP (s1); > + > + for (i = 0; i < 64; ++i) Add a comment for these magic numbers. > + do_page_test (json_ctx, (3988 / CHARBYTES) + i, > + (2636 / CHARBYTES), s2); Call do_one_test_page() > + > + free (s2); > +} > + > int > test_main (void) > { > @@ -267,6 +381,9 @@ test_main (void) > do_test_limit (&json_ctx, 0, 0, 15 - i, 16 - i, 255, -1); > } > > + do_test_page_boundary (&json_ctx); > + do_test_page (&json_ctx); OK. > + > json_array_end (&json_ctx); > json_attr_object_end (&json_ctx); > json_attr_object_end (&json_ctx); > -- Cheers, Carlos.