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([2804:1b3:a7c2:94e:b32d:2af9:e993:fe7c]) by smtp.gmail.com with ESMTPSA id 16-20020aa79150000000b006c2fcb25c15sm1466578pfi.162.2023.11.23.09.29.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Nov 2023 09:29:21 -0800 (PST) From: Adhemerval Zanella To: libc-alpha@sourceware.org, DJ Delorie Cc: Zhangfei Gao Subject: [PATCH v2 1/2] elf: Add a way to check if tunable is set (BZ 27069) Date: Thu, 23 Nov 2023 14:29:14 -0300 Message-Id: <20231123172915.893408-2-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231123172915.893408-1-adhemerval.zanella@linaro.org> References: <20231123172915.893408-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org The patch adds two new macros, TUNABLE_GET_DEFAULT and TUNABLE_IS_INITIALIZED, here the former get the default value with a signature similar to TUNABLE_GET, while the later returns whether the tunable was set by the environment variable. Checked on x86_64-linux-gnu. Reviewed-by: DJ Delorie --- elf/Versions | 1 + elf/dl-tunable-types.h | 1 + elf/dl-tunables.c | 40 ++++++++++++++++++++++++++++++++++++++++ elf/dl-tunables.h | 28 ++++++++++++++++++++++++++++ elf/dl-tunables.list | 1 + scripts/gen-tunables.awk | 4 ++-- 6 files changed, 73 insertions(+), 2 deletions(-) diff --git a/elf/Versions b/elf/Versions index 4614acea3e..1591031da9 100644 --- a/elf/Versions +++ b/elf/Versions @@ -77,6 +77,7 @@ ld { _dl_signal_error; # Set value of a tunable. + __tunable_is_initialized; __tunable_get_val; } } diff --git a/elf/dl-tunable-types.h b/elf/dl-tunable-types.h index 62d6d9e629..a2048058fa 100644 --- a/elf/dl-tunable-types.h +++ b/elf/dl-tunable-types.h @@ -61,6 +61,7 @@ struct _tunable { const char name[TUNABLE_NAME_MAX]; /* Internal name of the tunable. */ tunable_type_t type; /* Data type of the tunable. */ + const tunable_val_t def; /* The value. */ tunable_val_t val; /* The value. */ bool initialized; /* Flag to indicate that the tunable is initialized. */ diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c index 83265bc00b..644d21d1b0 100644 --- a/elf/dl-tunables.c +++ b/elf/dl-tunables.c @@ -145,6 +145,13 @@ tunable_initialize (tunable_t *cur, const char *strval) do_tunable_update_val (cur, &val, NULL, NULL); } +bool +__tunable_is_initialized (tunable_id_t id) +{ + return tunable_list[id].initialized; +} +rtld_hidden_def (__tunable_is_initialized) + void __tunable_set_val (tunable_id_t id, tunable_val_t *valp, tunable_num_t *minp, tunable_num_t *maxp) @@ -333,6 +340,39 @@ __tunables_print (void) } } +void +__tunable_get_default (tunable_id_t id, void *valp) +{ + tunable_t *cur = &tunable_list[id]; + + switch (cur->type.type_code) + { + case TUNABLE_TYPE_UINT_64: + { + *((uint64_t *) valp) = (uint64_t) cur->def.numval; + break; + } + case TUNABLE_TYPE_INT_32: + { + *((int32_t *) valp) = (int32_t) cur->def.numval; + break; + } + case TUNABLE_TYPE_SIZE_T: + { + *((size_t *) valp) = (size_t) cur->def.numval; + break; + } + case TUNABLE_TYPE_STRING: + { + *((const char **)valp) = cur->def.strval; + break; + } + default: + __builtin_unreachable (); + } +} +rtld_hidden_def (__tunable_get_default) + /* Set the tunable value. This is called by the module that the tunable exists in. */ void diff --git a/elf/dl-tunables.h b/elf/dl-tunables.h index 45c191e021..0df4dde24e 100644 --- a/elf/dl-tunables.h +++ b/elf/dl-tunables.h @@ -45,18 +45,26 @@ typedef void (*tunable_callback_t) (tunable_val_t *); extern void __tunables_init (char **); extern void __tunables_print (void); +extern bool __tunable_is_initialized (tunable_id_t); extern void __tunable_get_val (tunable_id_t, void *, tunable_callback_t); extern void __tunable_set_val (tunable_id_t, tunable_val_t *, tunable_num_t *, tunable_num_t *); +extern void __tunable_get_default (tunable_id_t id, void *valp); rtld_hidden_proto (__tunables_init) rtld_hidden_proto (__tunables_print) +rtld_hidden_proto (__tunable_is_initialized) rtld_hidden_proto (__tunable_get_val) rtld_hidden_proto (__tunable_set_val) +rtld_hidden_proto (__tunable_get_default) /* Define TUNABLE_GET and TUNABLE_SET in short form if TOP_NAMESPACE and TUNABLE_NAMESPACE are defined. This is useful shorthand to get and set tunables within a module. */ #if defined TOP_NAMESPACE && defined TUNABLE_NAMESPACE +# define TUNABLE_IS_INITIALIZED(__id) \ + TUNABLE_IS_INITIALIZED_FULL(TOP_NAMESPACE, TUNABLE_NAMESPACE, __id) +# define TUNABLE_GET_DEFAULT(__id, __type) \ + TUNABLE_GET_DEFAULT_FULL(TOP_NAMESPACE, TUNABLE_NAMESPACE,__id, __type) # define TUNABLE_GET(__id, __type, __cb) \ TUNABLE_GET_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, __type, __cb) # define TUNABLE_SET(__id, __val) \ @@ -65,6 +73,10 @@ rtld_hidden_proto (__tunable_set_val) TUNABLE_SET_WITH_BOUNDS_FULL (TOP_NAMESPACE, TUNABLE_NAMESPACE, __id, \ __val, __min, __max) #else +# define TUNABLE_IS_INITIALIZED(__top, __ns, __id) \ + TUNABLE_IS_INITIALIZED_FULL(__top, __ns, __id) +# define TUNABLE_GET_DEFAULT(__top, __ns, __type) \ + TUNABLE_GET_DEFAULT_FULL(__top, __ns, __id, __type) # define TUNABLE_GET(__top, __ns, __id, __type, __cb) \ TUNABLE_GET_FULL (__top, __ns, __id, __type, __cb) # define TUNABLE_SET(__top, __ns, __id, __val) \ @@ -73,6 +85,22 @@ rtld_hidden_proto (__tunable_set_val) TUNABLE_SET_WITH_BOUNDS_FULL (__top, __ns, __id, __val, __min, __max) #endif +/* Return whether the tunable was initialized by the environment variable. */ +#define TUNABLE_IS_INITIALIZED_FULL(__top, __ns, __id) \ +({ \ + tunable_id_t id = TUNABLE_ENUM_NAME (__top, __ns, __id); \ + __tunable_is_initialized (id); \ +}) + +/* Return the default value of the tunable. */ +#define TUNABLE_GET_DEFAULT_FULL(__top, __ns, __id, __type) \ +({ \ + tunable_id_t id = TUNABLE_ENUM_NAME (__top, __ns, __id); \ + __type __ret; \ + __tunable_get_default (id, &__ret); \ + __ret; \ +}) + /* Get and return a tunable value. If the tunable was set externally and __CB is defined then call __CB before returning the value. */ #define TUNABLE_GET_FULL(__top, __ns, __id, __type, __cb) \ diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list index 720a8ac49c..1b23fc9473 100644 --- a/elf/dl-tunables.list +++ b/elf/dl-tunables.list @@ -20,6 +20,7 @@ # type: Defaults to STRING # minval: Optional minimum acceptable value # maxval: Optional maximum acceptable value +# default: Optional default value (if not specified it will be 0 or "") # env_alias: An alias environment variable glibc { diff --git a/scripts/gen-tunables.awk b/scripts/gen-tunables.awk index 1e9d6b534e..9f5336381e 100644 --- a/scripts/gen-tunables.awk +++ b/scripts/gen-tunables.awk @@ -163,8 +163,8 @@ END { n = indices[2]; m = indices[3]; printf (" {TUNABLE_NAME_S(%s, %s, %s)", t, n, m) - printf (", {TUNABLE_TYPE_%s, %s, %s}, {%s}, false, %s},\n", - types[t,n,m], minvals[t,n,m], maxvals[t,n,m], + printf (", {TUNABLE_TYPE_%s, %s, %s}, {%s}, {%s}, false, %s},\n", + types[t,n,m], minvals[t,n,m], maxvals[t,n,m], default_val[t,n,m], default_val[t,n,m], env_alias[t,n,m]); } print "};" From patchwork Thu Nov 23 17:29:15 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella X-Patchwork-Id: 80652 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id D24103857C7E for ; Thu, 23 Nov 2023 17:29:40 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by sourceware.org (Postfix) with ESMTPS id 0E91C385841B for ; Thu, 23 Nov 2023 17:29:25 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 0E91C385841B Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=linaro.org ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 0E91C385841B Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2607:f8b0:4864:20::42b ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1700760566; cv=none; b=PkPzY5kVivy4PMvbJmyzZspIhHerNXjQim0MefQB4w7Ldxt9EWEfhNq4XdmWYzTmvEMfPnAX65aqMnK+V+A8ozSK3I5IT9vtaaVhl/UAq6khCrh4Ft5xvSvZbBGRU6MEZuLqw5RxypZ/8/LOI5/8s+DRW1gKjiNX9mtTRsLcl5M= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1700760566; c=relaxed/simple; bh=fu9fqQPysqLW+4ihIaoIuQWazerxcNBuNYwBFj8awFw=; h=DKIM-Signature:From:To:Subject:Date:Message-Id:MIME-Version; b=SZz3anMILxmpOkjTY+66Jzx6ek+0gX3zl+4sn6JA07ZA/O1lRKUhsFIW+1Upg5lPVhA6NukWodXdFoYto8bj9VYhqNQ5q3rsOSD/5YVGh5BK9nuk33skzPEDp+JniCLwa5dNdBBW67Za8qI62nzNXdj9geIJVgFNuM19C0PWdGA= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-pf1-x42b.google.com with SMTP id d2e1a72fcca58-6c4cf0aea06so1093350b3a.0 for ; Thu, 23 Nov 2023 09:29:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1700760563; x=1701365363; darn=sourceware.org; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:from:to:cc:subject:date :message-id:reply-to; bh=nvOMmR5nPPRiCAP9uZifd0VYB7zzegrn6fbP+R0su68=; b=M1j5mYFnNwghq1UI/BSKzLHydqtnp5fhDQ/hXAkSC1r4UtxpbrxPM99jvL/QPYqfYn bJ1lh0r93cKh4iqujRTnX7sAsGO3tAQzDdH8A/AaSrewVjv0G5r9cut8FO1F55iwjVL5 QnbTrOBW/roABY/dyvemBZou1/uEboQMf7EVOLmd4w9vhL5HTeWQvRaj3MWi3VHgxilN 7NGKhsNuLQAA3xXkMCSrN37PXRfD1QB9pXZ7SClRISzXDjq/ayR8WVBHTsPXYDhMSAKd Byn9M/UELxAPiNvywaAw2Ay5Vbf7HX8BOdEqaVPIycyc1KJB67hI2ZBXGmIw56MMiwOX 8nvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1700760563; x=1701365363; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:cc:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=nvOMmR5nPPRiCAP9uZifd0VYB7zzegrn6fbP+R0su68=; b=mmHs1LakcXUNvDu6U/LK0RXket5y0rMaQvuPakJ/R1qSQ91KRwdcH+Grf4XomQ3vjk 9F3SZN2VOeGXESy6tPveppzzEXAgjk8dCm8UOHBgy3x0+LY2gNcbkD7SABm9hBx6qOKg G6n3Ed+uVz5T24ATumXEkgMISv222WL7ROg5oOZBLNHTpYPdH4zwF187PQw+GaYRXYLY aAgGeJojFv7Nm8DfguVwoJoRF3QTbPlekZ7+cFMYZ/NJ30ypBqFqu6NBS0uLqenl4wQj uzaUv0KXKXgSVdvY2pHFlCz7i4Z8YyaxF0LjiTnQZB5Yoa9G3wnAJaYMdRLNP2Gy5rAM 1MEg== X-Gm-Message-State: AOJu0YzVfnb51gioRh65HOeq8qd3/L6WSj+T8ML0czxX4iKLszp2jzJ/ 42Q9UeU/tUNXD3V/7qjvsj/IWiz6RknhDDVsjpZtNg== X-Google-Smtp-Source: AGHT+IFJTCS1k2+jJA37PmgRKahAZvn75EH3G6xc8wvsMrveEQ/xifrT3TvwUHd+H4pkREBuGJ/EVA== X-Received: by 2002:a05:6a20:8418:b0:187:5302:4b2e with SMTP id c24-20020a056a20841800b0018753024b2emr285300pzd.41.1700760563663; Thu, 23 Nov 2023 09:29:23 -0800 (PST) Received: from mandiga.. ([2804:1b3:a7c2:94e:b32d:2af9:e993:fe7c]) by smtp.gmail.com with ESMTPSA id 16-20020aa79150000000b006c2fcb25c15sm1466578pfi.162.2023.11.23.09.29.22 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 23 Nov 2023 09:29:23 -0800 (PST) From: Adhemerval Zanella To: libc-alpha@sourceware.org, DJ Delorie Cc: Zhangfei Gao Subject: [PATCH v2 2/2] malloc: Improve MAP_HUGETLB with glibc.malloc.hugetlb=2 Date: Thu, 23 Nov 2023 14:29:15 -0300 Message-Id: <20231123172915.893408-3-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231123172915.893408-1-adhemerval.zanella@linaro.org> References: <20231123172915.893408-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_NUMSUBJECT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Even for explicit large page support, allocation might use mmap without the hugepage bit set if the requested size is smaller than mmap_threshold. For this case where mmap is issued, MAP_HUGETLB is set iff the allocation size is larger than the used large page. To force such allocations to use large pages, also tune the mmap_threhold (if it is not explicit set by a tunable). This forces allocation to follow the sbrk path, which will fall back to mmap (which will try large pages before galling back to default mmap). Checked on x86_64-linux-gnu. Reviewed-by: DJ Delorie --- malloc/arena.c | 13 ++++++++++--- 1 file changed, 10 insertions(+), 3 deletions(-) diff --git a/malloc/arena.c b/malloc/arena.c index a1a75e5a2b..c73f68890d 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -312,10 +312,17 @@ ptmalloc_init (void) # endif TUNABLE_GET (mxfast, size_t, TUNABLE_CALLBACK (set_mxfast)); TUNABLE_GET (hugetlb, size_t, TUNABLE_CALLBACK (set_hugetlb)); + if (mp_.hp_pagesize > 0) - /* Force mmap for main arena instead of sbrk, so hugepages are explicitly - used. */ - __always_fail_morecore = true; + { + /* Force mmap for main arena instead of sbrk, so MAP_HUGETLB is always + tried. Also tune the mmap threshold, so allocation smaller than the + large page will also try to use large pages by falling back + to sysmalloc_mmap_fallback on sysmalloc. */ + if (!TUNABLE_IS_INITIALIZED (mmap_threshold)) + do_set_mmap_threshold (mp_.hp_pagesize); + __always_fail_morecore = true; + } } /* Managing heaps and arenas (for concurrent threads) */