From patchwork Wed Nov 11 20:43:15 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Samuel Thibault X-Patchwork-Id: 41022 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 13D823984003; Wed, 11 Nov 2020 20:43:28 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from hera.aquilenet.fr (hera.aquilenet.fr [185.233.100.1]) by sourceware.org (Postfix) with ESMTPS id 7DD983833021 for ; Wed, 11 Nov 2020 20:43:24 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 7DD983833021 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=ens-lyon.org Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=samuel.thibault@ens-lyon.org Received: from localhost (localhost [127.0.0.1]) by hera.aquilenet.fr (Postfix) with ESMTP id 672CBD93; Wed, 11 Nov 2020 21:43:23 +0100 (CET) X-Virus-Scanned: Debian amavisd-new at aquilenet.fr Received: from hera.aquilenet.fr ([127.0.0.1]) by localhost (hera.aquilenet.fr [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id gk-1deypix-z; Wed, 11 Nov 2020 21:43:21 +0100 (CET) Received: from function.youpi.perso.aquilenet.fr (lfbn-bor-1-56-204.w90-50.abo.wanadoo.fr [90.50.148.204]) by hera.aquilenet.fr (Postfix) with ESMTPSA id 257FBDB6; Wed, 11 Nov 2020 21:43:20 +0100 (CET) Received: from samy by function.youpi.perso.aquilenet.fr with local (Exim 4.94) (envelope-from ) id 1kcwxZ-002Unw-Ra; Wed, 11 Nov 2020 21:43:17 +0100 From: Samuel Thibault To: libc-alpha@sourceware.org Subject: [hurd,commited 3/4] htl: Initialize later Date: Wed, 11 Nov 2020 21:43:15 +0100 Message-Id: <20201111204316.595017-4-samuel.thibault@ens-lyon.org> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201111204316.595017-1-samuel.thibault@ens-lyon.org> References: <20201111204316.595017-1-samuel.thibault@ens-lyon.org> MIME-Version: 1.0 X-Spam-Status: No, score=-11.4 required=5.0 tests=BAYES_00, GIT_PATCH_0, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, SPF_HELO_PASS, 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: , Cc: commit-hurd@gnu.org Errors-To: libc-alpha-bounces@sourceware.org Sender: "Libc-alpha" Since htl does not actually need a stack switch, we can initialize it like nptl is, avoiding all sorts of startup issues with ifunc. More precisely, htl defines __pthread_initialize_minimal instead of the elder _cthread_init_routine. We can then drop the stack switching dances. --- htl/Versions | 4 +- htl/libpthread_syms.a | 2 +- hurd/Versions | 3 - sysdeps/mach/hurd/htl/pt-sysdep.c | 19 +--- sysdeps/mach/hurd/i386/init-first.c | 106 +++++----------------- sysdeps/mach/hurd/i386/libc.abilist | 1 - sysdeps/mach/hurd/i386/libpthread.abilist | 1 - sysdeps/mach/i386/sysdep.h | 10 -- sysdeps/mach/sysdep.h | 8 -- 9 files changed, 32 insertions(+), 122 deletions(-) diff --git a/htl/Versions b/htl/Versions index 832cc5d814..4e23c2ed64 100644 --- a/htl/Versions +++ b/htl/Versions @@ -43,8 +43,6 @@ libpthread { __pthread_mutex_transfer_np; - _cthread_init_routine; - cthread_detach; cthread_fork; cthread_keycreate; @@ -168,6 +166,8 @@ libpthread { } GLIBC_PRIVATE { + __pthread_initialize_minimal; + __shm_directory; __pthread_threads; diff --git a/htl/libpthread_syms.a b/htl/libpthread_syms.a index 3801ec93c8..48dadfbd5f 100644 --- a/htl/libpthread_syms.a +++ b/htl/libpthread_syms.a @@ -1,6 +1,6 @@ /* pthread initializer is weak in glibc. It must be included if glibc is to start threading. */ -EXTERN(_cthread_init_routine) +EXTERN(__pthread_initialize_minimal) /* Weak references in glibc that must be filled if glibc is to be thread safe. */ diff --git a/hurd/Versions b/hurd/Versions index 9b5448ab2f..aa27f0f098 100644 --- a/hurd/Versions +++ b/hurd/Versions @@ -143,9 +143,6 @@ libc { __cthread_fork; __cthread_detach; __pthread_getattr_np; __pthread_attr_getstack; - # variables used for detecting cthreads - _cthread_exit_routine; _cthread_init_routine; - # cthreads functions with stubs in libc __cthread_keycreate; __cthread_getspecific; __cthread_setspecific; } diff --git a/sysdeps/mach/hurd/htl/pt-sysdep.c b/sysdeps/mach/hurd/htl/pt-sysdep.c index 0963b44878..8ca549dd73 100644 --- a/sysdeps/mach/hurd/htl/pt-sysdep.c +++ b/sysdeps/mach/hurd/htl/pt-sysdep.c @@ -28,13 +28,6 @@ __thread struct __pthread *___pthread_self; -/* Forward. */ -static void *init_routine (void); - -/* OK, the name of this variable isn't really appropriate, but I don't - want to change it yet. */ -void *(*_cthread_init_routine) (void) = &init_routine; - static void reset_pthread_total (void) { @@ -45,7 +38,7 @@ reset_pthread_total (void) /* This function is called from the Hurd-specific startup code. It should return a new stack pointer for the main thread. The caller will switch to this new stack before doing anything serious. */ -static void * +static void _init_routine (void *stack) { struct __pthread *thread; @@ -54,7 +47,7 @@ _init_routine (void *stack) if (__pthread_threads != NULL) /* Already initialized */ - return 0; + return; /* Initialize the library. */ ___pthread_init (); @@ -96,14 +89,12 @@ _init_routine (void *stack) /* Make MiG code thread aware. */ __mig_init (thread->stackaddr); - - return thread->mcontext.sp; } -static void * -init_routine (void) +void +__pthread_initialize_minimal (void) { - return _init_routine (0); + _init_routine (__libc_stack_end); } #ifdef SHARED diff --git a/sysdeps/mach/hurd/i386/init-first.c b/sysdeps/mach/hurd/i386/init-first.c index 5e66602d4b..6c35dc8104 100644 --- a/sysdeps/mach/hurd/i386/init-first.c +++ b/sysdeps/mach/hurd/i386/init-first.c @@ -46,9 +46,6 @@ extern int __libc_argc attribute_hidden; extern char **__libc_argv attribute_hidden; extern char **_dl_argv; -extern void *(*_cthread_init_routine) (void) __attribute__ ((weak)); -void (*_cthread_exit_routine) (int status) __attribute__ ((__noreturn__)); - /* Things that want to be run before _hurd_init or much anything else. Importantly, these are called before anything tries to use malloc. */ DEFINE_HOOK (_hurd_preinit_hook, (void)); @@ -96,10 +93,6 @@ init1 (int argc, char *arg0, ...) ++envp; d = (void *) ++envp; - /* Initialize libpthread if linked in. */ - if (__pthread_initialize_minimal != NULL) - __pthread_initialize_minimal (); - if ((void *) d == argv[0]) /* No Hurd data block to process. */ return; @@ -145,7 +138,6 @@ init (int *data) int argc = *data; char **argv = (void *) (data + 1); char **envp = &argv[argc + 1]; - struct hurd_startup_data *d; /* Since the cthreads initialization code uses malloc, and the malloc initialization code needs to get at the environment, make @@ -154,11 +146,13 @@ init (int *data) stored. */ __environ = envp; +#ifndef SHARED + struct hurd_startup_data *d; + while (*envp) ++envp; d = (void *) ++envp; -#ifndef SHARED /* If we are the bootstrap task started by the kernel, then after the environment pointers there is no Hurd data block; the argument strings start there. */ @@ -190,79 +184,27 @@ init (int *data) __libc_setup_tls (); #endif - /* After possibly switching stacks, call `init1' (above) with the user - code as the return address, and the argument data immediately above - that on the stack. */ - - if (&_cthread_init_routine && _cthread_init_routine) - { - /* Initialize cthreads, which will allocate us a new stack to run on. */ - int *newsp = (*_cthread_init_routine) (); - struct hurd_startup_data *od; - - void switch_stacks (void); - - __libc_stack_end = newsp; - - /* Copy the argdata from the old stack to the new one. */ - newsp = memcpy (newsp - ((char *) &d[1] - (char *) data), data, - (char *) d - (char *) data); - -#ifdef SHARED - /* And readjust the dynamic linker's idea of where the argument - vector lives. */ - assert (_dl_argv == argv); - _dl_argv = (void *) (newsp + 1); -#endif - - /* Set up the Hurd startup data block immediately following - the argument and environment pointers on the new stack. */ - od = ((void *) newsp + ((char *) d - (char *) data)); - if ((void *) argv[0] == d) - /* We were started up by the kernel with arguments on the stack. - There is no Hurd startup data, so zero the block. */ - memset (od, 0, sizeof *od); - else - /* Copy the Hurd startup data block to the new stack. */ - *od = *d; - - /* Push the user code address on the top of the new stack. It will - be the return address for `init1'; we will jump there with NEWSP - as the stack pointer. */ - /* The following expression would typically be written as - ``__builtin_return_address (0)''. But, for example, GCC 4.4.6 doesn't - recognize that this read operation may alias the following write - operation, and thus is free to reorder the two, clobbering the - original return address. */ - *--newsp = *((int *) __builtin_frame_address (0) + 1); - /* GCC 4.4.6 also wants us to force loading *NEWSP already here. */ - asm volatile ("# %0" : : "X" (*newsp)); - *((void **) __builtin_frame_address (0) + 1) = &switch_stacks; - /* Force NEWSP into %eax and &init1 into %ecx, which are not restored - by function return. */ - asm volatile ("# a %0 c %1" : : "a" (newsp), "c" (&init1)); - } - else - { - int usercode; - - void call_init1 (void); - - /* The argument data is just above the stack frame we will unwind by - returning. Mutate our own return address to run the code below. */ - /* The following expression would typically be written as - ``__builtin_return_address (0)''. But, for example, GCC 4.4.6 doesn't - recognize that this read operation may alias the following write - operation, and thus is free to reorder the two, clobbering the - original return address. */ - usercode = *((int *) __builtin_frame_address (0) + 1); - /* GCC 4.4.6 also wants us to force loading USERCODE already here. */ - asm volatile ("# %0" : : "X" (usercode)); - *((void **) __builtin_frame_address (0) + 1) = &call_init1; - /* Force USERCODE into %eax and &init1 into %ecx, which are not - restored by function return. */ - asm volatile ("# a %0 c %1" : : "a" (usercode), "c" (&init1)); - } + /* Call `init1' (above) with the user code as the return address, and the + argument data immediately above that on the stack. */ + + int usercode; + + void call_init1 (void); + + /* The argument data is just above the stack frame we will unwind by + returning. Mutate our own return address to run the code below. */ + /* The following expression would typically be written as + ``__builtin_return_address (0)''. But, for example, GCC 4.4.6 doesn't + recognize that this read operation may alias the following write + operation, and thus is free to reorder the two, clobbering the + original return address. */ + usercode = *((int *) __builtin_frame_address (0) + 1); + /* GCC 4.4.6 also wants us to force loading USERCODE already here. */ + asm volatile ("# %0" : : "X" (usercode)); + *((void **) __builtin_frame_address (0) + 1) = &call_init1; + /* Force USERCODE into %eax and &init1 into %ecx, which are not + restored by function return. */ + asm volatile ("# a %0 c %1" : : "a" (usercode), "c" (&init1)); DIAG_POP_NEEDS_COMMENT; /* -Warray-bounds. */ } diff --git a/sysdeps/mach/hurd/i386/libc.abilist b/sysdeps/mach/hurd/i386/libc.abilist index e2ff0e8b9e..7a5eb66b85 100644 --- a/sysdeps/mach/hurd/i386/libc.abilist +++ b/sysdeps/mach/hurd/i386/libc.abilist @@ -2333,4 +2333,3 @@ HURD_CTHREADS_0.3 __spin_lock_init F HURD_CTHREADS_0.3 __spin_lock_solid F HURD_CTHREADS_0.3 __spin_try_lock F HURD_CTHREADS_0.3 __spin_unlock F -HURD_CTHREADS_0.3 _cthread_exit_routine D 0x4 diff --git a/sysdeps/mach/hurd/i386/libpthread.abilist b/sysdeps/mach/hurd/i386/libpthread.abilist index a1e0a7183b..b9c9b75c28 100644 --- a/sysdeps/mach/hurd/i386/libpthread.abilist +++ b/sysdeps/mach/hurd/i386/libpthread.abilist @@ -10,7 +10,6 @@ GLIBC_2.12 __pthread_spin_init F GLIBC_2.12 __pthread_spin_lock F GLIBC_2.12 __pthread_spin_trylock F GLIBC_2.12 __pthread_spin_unlock F -GLIBC_2.12 _cthread_init_routine D 0x4 GLIBC_2.12 _cthreads_flockfile F GLIBC_2.12 _cthreads_ftrylockfile F GLIBC_2.12 _cthreads_funlockfile F diff --git a/sysdeps/mach/i386/sysdep.h b/sysdeps/mach/i386/sysdep.h index e849f120f9..c132b3a4c3 100644 --- a/sysdeps/mach/i386/sysdep.h +++ b/sysdeps/mach/i386/sysdep.h @@ -39,16 +39,6 @@ envp = p; \ } while (0) -#define CALL_WITH_SP(fn, info, sp) \ - do { \ - void **ptr = (void **) sp; \ - *--(__typeof (info) *) ptr = info; \ - ptr[-1] = ptr; \ - --ptr; \ - asm volatile ("movl %0, %%esp; call %1" : : \ - "g" (ptr), "m" (*(long int *) (fn)) : "%esp"); \ - } while (0) - #define RETURN_TO(sp, pc, retval) \ asm volatile ("movl %0, %%esp; jmp %*%1 # %2" \ : : "g" (sp), "r" (pc), "a" (retval)) diff --git a/sysdeps/mach/sysdep.h b/sysdeps/mach/sysdep.h index ba65015253..13ea04d980 100644 --- a/sysdeps/mach/sysdep.h +++ b/sysdeps/mach/sysdep.h @@ -62,14 +62,6 @@ #error SNARF_ARGS not defined by sysdeps/mach/MACHINE/sysdep.h #endif -/* Call the C function FN with no arguments, - on a stack starting at SP (as returned by *_cthread_init_routine). - You don't need to deal with FN returning; it shouldn't. */ -#ifndef CALL_WITH_SP -#define CALL_WITH_SP(fn, sp) -#error CALL_WITH_SP not defined by sysdeps/mach/MACHINE/sysdep.h -#endif - /* LOSE can be defined as the `halt' instruction or something similar which will cause the process to die in a characteristic way suggesting a bug. */