From patchwork Fri Jun 18 09:09:45 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Siddhesh Poyarekar X-Patchwork-Id: 43919 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 DEE7539B4405 for ; Fri, 18 Jun 2021 09:10:23 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org DEE7539B4405 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1624007423; bh=agzoREuZ7gKDWuML6fUX1jXHKwtsuxG8IB95CGXs0Mc=; h=To:Subject:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:From; b=LPjLMLuZ7UU8MmhFggZsTmABfa6fMLw+YA9Iwd7AM0Rkc9jOJzbcrF7hauG7l6Juy Zwk1Fsr3oV+UKejrt9hJhjnfoFqqWElHaBVrE77BzCoVYpUVjvwOH4ns8jIzYmG7Z4 3zzjdJAuZrMQHXctsRI+ekq+UYjdMI9jdi9gcz8Y= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from crocodile.elm.relay.mailchannels.net (crocodile.elm.relay.mailchannels.net [23.83.212.45]) by sourceware.org (Postfix) with ESMTPS id 0652139B4414 for ; Fri, 18 Jun 2021 09:10:00 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 0652139B4414 X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from relay.mailchannels.net (localhost [127.0.0.1]) by relay.mailchannels.net (Postfix) with ESMTP id AE6AA7E1FF7 for ; Fri, 18 Jun 2021 09:09:59 +0000 (UTC) Received: from pdx1-sub0-mail-a91.g.dreamhost.com (100-101-162-61.trex.outbound.svc.cluster.local [100.101.162.61]) (Authenticated sender: dreamhost) by relay.mailchannels.net (Postfix) with ESMTPA id 3730C7E2406 for ; Fri, 18 Jun 2021 09:09:59 +0000 (UTC) X-Sender-Id: dreamhost|x-authsender|siddhesh@gotplt.org Received: from pdx1-sub0-mail-a91.g.dreamhost.com (pop.dreamhost.com [64.90.62.162]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384) by 100.101.162.61 (trex/6.3.3); Fri, 18 Jun 2021 09:09:59 +0000 X-MC-Relay: Neutral X-MailChannels-SenderId: dreamhost|x-authsender|siddhesh@gotplt.org X-MailChannels-Auth-Id: dreamhost X-Well-Made-Irritate: 0d8939fd54f9cbaa_1624007399449_4258810065 X-MC-Loop-Signature: 1624007399449:655899937 X-MC-Ingress-Time: 1624007399449 Received: from pdx1-sub0-mail-a91.g.dreamhost.com (localhost [127.0.0.1]) by pdx1-sub0-mail-a91.g.dreamhost.com (Postfix) with ESMTP id F0F377E3B8 for ; Fri, 18 Jun 2021 02:09:58 -0700 (PDT) Received: from rhbox.intra.reserved-bit.com (unknown [1.186.101.110]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: siddhesh@gotplt.org) by pdx1-sub0-mail-a91.g.dreamhost.com (Postfix) with ESMTPSA id C1DCB7E6CF for ; Fri, 18 Jun 2021 02:09:57 -0700 (PDT) X-DH-BACKEND: pdx1-sub0-mail-a91 To: libc-alpha@sourceware.org Subject: [PATCH] malloc: Clean up __malloc_initialized Date: Fri, 18 Jun 2021 14:39:45 +0530 Message-Id: <20210618090945.721332-1-siddhesh@sourceware.org> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 X-Spam-Status: No, score=-3494.6 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_NONE, KAM_DMARC_STATUS, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_NEUTRAL, 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-Patchwork-Original-From: Siddhesh Poyarekar via Libc-alpha From: Siddhesh Poyarekar Reply-To: Siddhesh Poyarekar Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" It can be assumed that ptmalloc_init is always called in a single-threaded context because pthread_create calls malloc before spawning a thread. As a result, a boolean value for __malloc_initialized is sufficient to ensure that the function body is executed only once. Further, __malloc_initialized is mentioned in Versions when it is actually an internal symbol. Drop that reference and also remove its declaration from include/malloc.h since ideally it should not be used anywhere outside malloc. mcheck uses it (and hence needs an extern decl), but mcheck is broken enough that this use is just a small chink in an already cracked vase. --- include/malloc.h | 6 ------ malloc/Versions | 2 +- malloc/arena.c | 16 +++++++++------- malloc/malloc.c | 14 +++++++------- malloc/mcheck.c | 5 ++++- 5 files changed, 21 insertions(+), 22 deletions(-) diff --git a/include/malloc.h b/include/malloc.h index b77761f74d..f9c9610548 100644 --- a/include/malloc.h +++ b/include/malloc.h @@ -5,12 +5,6 @@ # ifndef _ISOMAC # include -/* In the GNU libc we rename the global variable - `__malloc_initialized' to `__libc_malloc_initialized'. */ -#define __malloc_initialized __libc_malloc_initialized -/* Nonzero if the malloc is already initialized. */ -extern int __malloc_initialized attribute_hidden; - struct malloc_state; typedef struct malloc_state *mstate; diff --git a/malloc/Versions b/malloc/Versions index 6693c46ee2..62e4698a08 100644 --- a/malloc/Versions +++ b/malloc/Versions @@ -9,7 +9,7 @@ libc { __libc_valloc; __malloc_initialize_hook; __free_hook; __malloc_hook; __realloc_hook; __memalign_hook; __after_morecore_hook; - __malloc_initialized; __default_morecore; __morecore; + __default_morecore; __morecore; # functions used in inline functions or macros _obstack_allocated_p; _obstack_begin; _obstack_begin_1; diff --git a/malloc/arena.c b/malloc/arena.c index 7eb110445e..bb14bc5ca9 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -97,7 +97,7 @@ static mstate free_list; __libc_lock_define_initialized (static, list_lock); /* Already initialized? */ -int __malloc_initialized = -1; +bool __malloc_initialized; /**************************************************************************/ @@ -143,7 +143,7 @@ int __malloc_initialized = -1; void __malloc_fork_lock_parent (void) { - if (__malloc_initialized < 1) + if (!__malloc_initialized) return; /* We do not acquire free_list_lock here because we completely @@ -163,7 +163,7 @@ __malloc_fork_lock_parent (void) void __malloc_fork_unlock_parent (void) { - if (__malloc_initialized < 1) + if (!__malloc_initialized) return; for (mstate ar_ptr = &main_arena;; ) @@ -179,7 +179,7 @@ __malloc_fork_unlock_parent (void) void __malloc_fork_unlock_child (void) { - if (__malloc_initialized < 1) + if (!__malloc_initialized) return; /* Push all arenas to the free list, except thread_arena, which is @@ -287,13 +287,16 @@ extern struct dl_open_hook *_dl_open_hook; libc_hidden_proto (_dl_open_hook); #endif +/* Malloc initialization. We assume that the function is always called in a + single threaded context because pthread_create calls malloc before spawning + a thread. */ static void ptmalloc_init (void) { - if (__malloc_initialized >= 0) + if (__malloc_initialized) return; - __malloc_initialized = 0; + __malloc_initialized = true; #ifdef USE_MTAG if ((TUNABLE_GET_FULL (glibc, mem, tagging, int32_t, NULL) & 1) != 0) @@ -410,7 +413,6 @@ ptmalloc_init (void) if (hook != NULL) (*hook)(); #endif - __malloc_initialized = 1; } /* Managing heaps and arenas (for concurrent threads) */ diff --git a/malloc/malloc.c b/malloc/malloc.c index 0e2e1747e0..0ba50a497b 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -3562,7 +3562,7 @@ libc_hidden_def (__libc_memalign) void * __libc_valloc (size_t bytes) { - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); void *address = RETURN_ADDRESS (0); @@ -3573,7 +3573,7 @@ __libc_valloc (size_t bytes) void * __libc_pvalloc (size_t bytes) { - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); void *address = RETURN_ADDRESS (0); @@ -5077,7 +5077,7 @@ __malloc_trim (size_t s) { int result = 0; - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); mstate ar_ptr = &main_arena; @@ -5212,7 +5212,7 @@ __libc_mallinfo2 (void) struct mallinfo2 m; mstate ar_ptr; - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); memset (&m, 0, sizeof (m)); @@ -5263,7 +5263,7 @@ __malloc_stats (void) mstate ar_ptr; unsigned int in_use_b = mp_.mmapped_mem, system_b = in_use_b; - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); _IO_flockfile (stderr); int old_flags2 = stderr->_flags2; @@ -5432,7 +5432,7 @@ __libc_mallopt (int param_number, int value) mstate av = &main_arena; int res = 1; - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); __libc_lock_lock (av->mutex); @@ -5691,7 +5691,7 @@ __malloc_info (int options, FILE *fp) - if (__malloc_initialized < 0) + if (!__malloc_initialized) ptmalloc_init (); fputs ("\n", fp); diff --git a/malloc/mcheck.c b/malloc/mcheck.c index 2a1fc645d4..93d7992a41 100644 --- a/malloc/mcheck.c +++ b/malloc/mcheck.c @@ -21,6 +21,7 @@ # define _MALLOC_INTERNAL # include # include +# include # include # include # include @@ -372,10 +373,12 @@ mabort (enum mcheck_status status) int mcheck (void (*func) (enum mcheck_status)) { + extern bool __malloc_initialized; + abortfunc = (func != NULL) ? func : &mabort; /* These hooks may not be safely inserted if malloc is already in use. */ - if (__malloc_initialized <= 0 && !mcheck_used) + if (!__malloc_initialized && !mcheck_used) { /* We call malloc() once here to ensure it is initialized. */ void *p = malloc (0);