From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 605D7C4345F for ; Fri, 19 Apr 2024 07:42:54 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 0DD2D10E599; Fri, 19 Apr 2024 07:42:54 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=ursulin-net.20230601.gappssmtp.com header.i=@ursulin-net.20230601.gappssmtp.com header.b="QpEG05EW"; dkim-atps=neutral Received: from mail-wm1-f48.google.com (mail-wm1-f48.google.com [209.85.128.48]) by gabe.freedesktop.org (Postfix) with ESMTPS id 281AA10E599 for ; Fri, 19 Apr 2024 07:42:53 +0000 (UTC) Received: by mail-wm1-f48.google.com with SMTP id 5b1f17b1804b1-418bbc690e1so14522785e9.2 for ; Fri, 19 Apr 2024 00:42:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ursulin-net.20230601.gappssmtp.com; s=20230601; t=1713512571; x=1714117371; darn=lists.freedesktop.org; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=ATg5w/4oB2udkJwFKOVZWe/V7X6BFJ3ki3erKh65SvM=; b=QpEG05EW7zu0AFoQCKVXPq8CAP1807g+reh89PQgMwWnW/5/DjcR426kfE/NKkwAck 98SetqlGfDVMqnvCjKJQS9oXkGfMm9N4N8oG8pIY9M0MdTRdaktAiE/MgwPR3duIWkP2 pwijG64NlDEf5uezrL8vEIdHsggI3R3FZboe0W6oTLTkYbxPnHIBKtvjKsgP1FcSjyau CBvgBVV2fwTdyVmON6ZKo8U8z8mipyPGPhTp9KqQFFQfRovEI/WrANmrbKvICuCSdBXc noaTYXrsb7zlvHvL18bnRBSN8E7+oo5HzKkC3jEdSAHGbvz0Q4vwYvCV0ilEJmcC2XwJ LIUQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713512571; x=1714117371; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ATg5w/4oB2udkJwFKOVZWe/V7X6BFJ3ki3erKh65SvM=; b=NXYnNEHBEZ4lXUL7f/5+lp+uNF6blcsAqW5nTSM77nPY7uIp5loPXCNzkTFjAUzwzc UVNtPi2fEL2k2oibCRLn6DAY6F2PWkIElUD1ClmGtaXCC0wTBs4k1a/dYAC9f/7xfNvY DEBis7980EqqiY0HWHTgNIyw1XtHm0Sgh+FXKgIgymuczW/LMTW/Xl7yuB5/aPw+irav VwgHodK4NYy6R8fp6be+HHxMj1+OBYZL/nc14TF4RkH4iGosDd39vLuIqnRksID+i4xk l182WvIY/gDACT4VpJLdgqNKaQ2CHJPVlPVTCFBTq0Hx6qNHr6VjLW0sUR88vYPI5Llf 1+3g== X-Forwarded-Encrypted: i=1; AJvYcCUsbljqU+BanKPeg9m1b6P33DTJw6v88bSTUGtwfCs8ua4yKtCtYLGeK/5KDjoknJPGhkX6EA6XsAg7xRMVs500Qpl/9uQj19hss1RoPw== X-Gm-Message-State: AOJu0YxscKIePPKnV4/LMzRaTYP0NtXb+UkDeZbFmzkkextFecN2doew M8hYw53yetREgFmPJpKZ5Rb1ivyS1QGDoToBwWrId4uyJzWWL/5YYjsLH19nCYI= X-Google-Smtp-Source: AGHT+IEDLvWekqJuPtachxPO4tXvL7lOS5/z7Da89WfS4ak33ix/m8NCQ7NVeuq2NJiVuJT73vXSrw== X-Received: by 2002:a05:600c:154f:b0:417:fbc2:caf8 with SMTP id f15-20020a05600c154f00b00417fbc2caf8mr819764wmg.23.1713512571132; Fri, 19 Apr 2024 00:42:51 -0700 (PDT) Received: from [192.168.0.101] ([84.65.0.132]) by smtp.gmail.com with ESMTPSA id m22-20020a05600c4f5600b004148d7b889asm9380812wmq.8.2024.04.19.00.42.50 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 19 Apr 2024 00:42:50 -0700 (PDT) Message-ID: <434d02cf-c683-40e6-b2f6-3462516a104e@ursulin.net> Date: Fri, 19 Apr 2024 08:42:50 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH i-g-t 01/12] lib/igt_drm_fdinfo: Stop passing key twice Content-Language: en-GB To: Lucas De Marchi , igt-dev@lists.freedesktop.org Cc: Umesh Nerlige Ramappa References: <20240405060056.59379-1-lucas.demarchi@intel.com> <20240405060056.59379-2-lucas.demarchi@intel.com> From: Tvrtko Ursulin In-Reply-To: <20240405060056.59379-2-lucas.demarchi@intel.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: igt-dev@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development mailing list for IGT GPU Tools List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: igt-dev-bounces@lists.freedesktop.org Sender: "igt-dev" On 05/04/2024 07:00, Lucas De Marchi wrote: > Change strstartswith() so it also returns the length, which then can be > used inside the branch when it matches. A good compiler shall optimize > out the strlen call since the argument is a constant literal. > > With this, the find_kv() is not needed anymore and the difference with > regard the other branches can be summarized with a new ignore_space() > helper and the fact it matches the entire key by appending the ':'. The > helper is added on top of the file so it can be reused later. > > Signed-off-by: Lucas De Marchi > --- > lib/igt_drm_fdinfo.c | 87 +++++++++++++++++++++++--------------------- > 1 file changed, 45 insertions(+), 42 deletions(-) > > diff --git a/lib/igt_drm_fdinfo.c b/lib/igt_drm_fdinfo.c > index 18dbb5d0b..bfc946f24 100644 > --- a/lib/igt_drm_fdinfo.c > +++ b/lib/igt_drm_fdinfo.c > @@ -53,6 +53,14 @@ static size_t read_fdinfo(char *buf, const size_t sz, int at, const char *name) > return count > 0 ? count : 0; > } > > +static const char *ignore_space(const char *s) > +{ > + for (; *s && isspace(*s); s++) > + ; > + > + return s; > +} > + > static int parse_engine(char *line, struct drm_client_fdinfo *info, > size_t prefix_len, > const char **name_map, unsigned int map_entries, > @@ -104,23 +112,6 @@ static int parse_engine(char *line, struct drm_client_fdinfo *info, > return found; > } > > -static const char *find_kv(const char *buf, const char *key, size_t keylen) > -{ > - const char *p; > - > - if (strncmp(buf, key, keylen)) > - return NULL; > - > - p = buf + keylen; > - if (*p != ':') > - return NULL; > - > - for (p++; *p && isspace(*p); p++) > - ; > - > - return *p ? p : NULL; > -} > - > static int parse_region(char *line, struct drm_client_fdinfo *info, > size_t prefix_len, > const char **region_map, unsigned int region_entries, > @@ -205,6 +196,11 @@ out: > } \ > } while (0) > > +#define strstartswith(a, b, plen__) ({ \ > + *plen__ = strlen(b); \ > + strncmp(a, b, *plen__) == 0; \ > +}) Did it have to be a macro for optimization to work? > + > unsigned int > __igt_parse_drm_fdinfo(int dir, const char *fd, struct drm_client_fdinfo *info, > const char **name_map, unsigned int map_entries, > @@ -222,31 +218,39 @@ __igt_parse_drm_fdinfo(int dir, const char *fd, struct drm_client_fdinfo *info, > > while ((l = strtok_r(_buf, "\n", &ctx))) { > uint64_t val = 0; > + size_t keylen; > const char *v; > int idx; > > _buf = NULL; > > - if ((v = find_kv(l, "drm-driver", strlen("drm-driver")))) { > - strncpy(info->driver, v, sizeof(info->driver) - 1); > - good++; > - } else if ((v = find_kv(l, "drm-client-id", > - strlen("drm-client-id")))) { > - info->id = atol(v); > - good++; > - } else if ((v = find_kv(l, "drm-pdev", strlen("drm-pdev")))) { > - /* optional */ > + if (strstartswith(l, "drm-driver:", &keylen)) { > + v = l + keylen; > + v = ignore_space(v); > + if (*v) { > + strncpy(info->driver, v, sizeof(info->driver) - 1); > + good++; > + } > + } else if (strstartswith(l, "drm-client-id:", &keylen)) { > + v = l + keylen; > + v = ignore_space(v); > + if (*v) { > + info->id = atol(v); > + good++; > + } > + } else if (strstartswith(l, "drm-pdev:", &keylen)) { > + v = l + keylen; > + v = ignore_space(v); Removing find_kv looks like a slight negative, given how now all branches have to repeat v = + keylen; v = ignore_space(v). I wonder if it would work by extending find_kv to allow prefix matching mode, something like this (only two branches show to illustrate the modes): ... } else if ((v = find_kv(l, "drm-pdev", MATCH_FULL, &keylen))) { /* optional */ strncpy(info->pdev, v, sizeof(info->pdev) - 1); } else if (find_kv(l, "drm-engine-capacity-", MATCH_PREFIX)) { idx = parse_engine(l, info, keylen, name_map, map_entries, &val); if (idx >= 0) { info->capacity[idx] = val; num_capacity++; } ... ? Regards, Tvrtko > strncpy(info->pdev, v, sizeof(info->pdev) - 1); > - } else if (!strncmp(l, "drm-engine-capacity-", 20)) { > - idx = parse_engine(l, info, > - strlen("drm-engine-capacity-"), > + } else if (strstartswith(l, "drm-engine-capacity-", &keylen)) { > + idx = parse_engine(l, info, keylen, > name_map, map_entries, &val); > if (idx >= 0) { > info->capacity[idx] = val; > num_capacity++; > } > - } else if (!strncmp(l, "drm-engine-", 11)) { > - idx = parse_engine(l, info, strlen("drm-engine-"), > + } else if (strstartswith(l, "drm-engine-", &keylen)) { > + idx = parse_engine(l, info, keylen, > name_map, map_entries, &val); > if (idx >= 0) { > if (!info->capacity[idx]) > @@ -256,25 +260,24 @@ __igt_parse_drm_fdinfo(int dir, const char *fd, struct drm_client_fdinfo *info, > if (idx > info->last_engine_index) > info->last_engine_index = idx; > } > - } else if (!strncmp(l, "drm-total-", 10)) { > - idx = parse_region(l, info, strlen("drm-total-"), > + } else if (strstartswith(l, "drm-total-", &keylen)) { > + idx = parse_region(l, info, keylen, > region_map, region_entries, &val); > UPDATE_REGION(idx, total, val); > - } else if (!strncmp(l, "drm-shared-", 11)) { > - idx = parse_region(l, info, strlen("drm-shared-"), > + } else if (strstartswith(l, "drm-shared-", &keylen)) { > + idx = parse_region(l, info, keylen, > region_map, region_entries, &val); > UPDATE_REGION(idx, shared, val); > - > - } else if (!strncmp(l, "drm-resident-", 13)) { > - idx = parse_region(l, info, strlen("drm-resident-"), > + } else if (strstartswith(l, "drm-resident-", &keylen)) { > + idx = parse_region(l, info, keylen, > region_map, region_entries, &val); > UPDATE_REGION(idx, resident, val); > - } else if (!strncmp(l, "drm-purgeable-", 14)) { > - idx = parse_region(l, info, strlen("drm-purgeable-"), > + } else if (strstartswith(l, "drm-purgeable-", &keylen)) { > + idx = parse_region(l, info, keylen, > region_map, region_entries, &val); > UPDATE_REGION(idx, purgeable, val); > - } else if (!strncmp(l, "drm-active-", 11)) { > - idx = parse_region(l, info, strlen("drm-active-"), > + } else if (strstartswith(l, "drm-active-", &keylen)) { > + idx = parse_region(l, info, keylen, > region_map, region_entries, &val); > UPDATE_REGION(idx, active, val); > }