From 3353a5a4cfcdc6ef58e1ec036bd3f47ebcc16f3c Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 25 Jun 2021 10:30:36 +0200 Subject: rt: Rework lio_listio implementation Move the common code into rt/lio_listio-common.c and include the file in both rt/lio_listio.c and rt/lio_listio64.c. The common code automatically defines both public symbols for __WORDSIZE == 64. Reviewed-by: Adhemerva Zanella --- rt/lio_listio.c | 235 ++------------------------------------------------------ 1 file changed, 6 insertions(+), 229 deletions(-) (limited to 'rt/lio_listio.c') diff --git a/rt/lio_listio.c b/rt/lio_listio.c index 2cab3c2254..a80865e5d7 100644 --- a/rt/lio_listio.c +++ b/rt/lio_listio.c @@ -1,7 +1,6 @@ /* Enqueue and list of read or write requests. - Copyright (C) 1997-2021 Free Software Foundation, Inc. + Copyright (C) 2021 Free Software Foundation, Inc. This file is part of the GNU C Library. - Contributed by Ulrich Drepper , 1997. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -17,232 +16,10 @@ License along with the GNU C Library; if not, see . */ -#ifndef lio_listio -#include -#include -#include -#include -#include - -#include - +#define LIO_LISTIO lio_listio +#define AIOCB aiocb +#define LIO_LISTIO_OLD __lio_listio_21 +#define LIO_LISTIO_NEW __lio_listio_24 #define LIO_OPCODE_BASE 0 -#endif - -#include - - -/* We need this special structure to handle asynchronous I/O. */ -struct async_waitlist - { - unsigned int counter; - struct sigevent sigev; - struct waitlist list[0]; - }; - - -/* The code in glibc 2.1 to glibc 2.4 issued only one event when all - requests submitted with lio_listio finished. The existing practice - is to issue events for the individual requests as well. This is - what the new code does. */ -#if SHLIB_COMPAT (librt, GLIBC_2_1, GLIBC_2_4) -# define LIO_MODE(mode) ((mode) & 127) -# define NO_INDIVIDUAL_EVENT_P(mode) ((mode) & 128) -#else -# define LIO_MODE(mode) mode -# define NO_INDIVIDUAL_EVENT_P(mode) 0 -#endif - - -static int -lio_listio_internal (int mode, struct aiocb *const list[], int nent, - struct sigevent *sig) -{ - struct sigevent defsigev; - struct requestlist *requests[nent]; - int cnt; - volatile unsigned int total = 0; - int result = 0; - - if (sig == NULL) - { - defsigev.sigev_notify = SIGEV_NONE; - sig = &defsigev; - } - - /* Request the mutex. */ - pthread_mutex_lock (&__aio_requests_mutex); - - /* Now we can enqueue all requests. Since we already acquired the - mutex the enqueue function need not do this. */ - for (cnt = 0; cnt < nent; ++cnt) - if (list[cnt] != NULL && list[cnt]->aio_lio_opcode != LIO_NOP) - { - if (NO_INDIVIDUAL_EVENT_P (mode)) - list[cnt]->aio_sigevent.sigev_notify = SIGEV_NONE; - - requests[cnt] = __aio_enqueue_request ((aiocb_union *) list[cnt], - (list[cnt]->aio_lio_opcode - | LIO_OPCODE_BASE)); - - if (requests[cnt] != NULL) - /* Successfully enqueued. */ - ++total; - else - /* Signal that we've seen an error. `errno' and the error code - of the aiocb will tell more. */ - result = -1; - } - else - requests[cnt] = NULL; - - if (total == 0) - { - /* We don't have anything to do except signalling if we work - asynchronously. */ - - /* Release the mutex. We do this before raising a signal since the - signal handler might do a `siglongjmp' and then the mutex is - locked forever. */ - pthread_mutex_unlock (&__aio_requests_mutex); - - if (LIO_MODE (mode) == LIO_NOWAIT) - __aio_notify_only (sig); - - return result; - } - else if (LIO_MODE (mode) == LIO_WAIT) - { -#ifndef DONT_NEED_AIO_MISC_COND - pthread_cond_t cond = PTHREAD_COND_INITIALIZER; - int oldstate; -#endif - struct waitlist waitlist[nent]; - - total = 0; - for (cnt = 0; cnt < nent; ++cnt) - { - assert (requests[cnt] == NULL || list[cnt] != NULL); - - if (requests[cnt] != NULL && list[cnt]->aio_lio_opcode != LIO_NOP) - { -#ifndef DONT_NEED_AIO_MISC_COND - waitlist[cnt].cond = &cond; -#endif - waitlist[cnt].result = &result; - waitlist[cnt].next = requests[cnt]->waiting; - waitlist[cnt].counterp = &total; - waitlist[cnt].sigevp = NULL; - requests[cnt]->waiting = &waitlist[cnt]; - ++total; - } - } - -#ifdef DONT_NEED_AIO_MISC_COND - AIO_MISC_WAIT (result, total, NULL, 0); -#else - /* Since `pthread_cond_wait'/`pthread_cond_timedwait' are cancellation - points we must be careful. We added entries to the waiting lists - which we must remove. So defer cancellation for now. */ - pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, &oldstate); - - while (total > 0) - pthread_cond_wait (&cond, &__aio_requests_mutex); - - /* Now it's time to restore the cancellation state. */ - pthread_setcancelstate (oldstate, NULL); - - /* Release the conditional variable. */ - if (pthread_cond_destroy (&cond) != 0) - /* This must never happen. */ - abort (); -#endif - - /* If any of the I/O requests failed, return -1 and set errno. */ - if (result != 0) - { - __set_errno (result == EINTR ? EINTR : EIO); - result = -1; - } - } - else - { - struct async_waitlist *waitlist; - - waitlist = (struct async_waitlist *) - malloc (sizeof (struct async_waitlist) - + (nent * sizeof (struct waitlist))); - - if (waitlist == NULL) - { - __set_errno (EAGAIN); - result = -1; - } - else - { - total = 0; - - for (cnt = 0; cnt < nent; ++cnt) - { - assert (requests[cnt] == NULL || list[cnt] != NULL); - - if (requests[cnt] != NULL - && list[cnt]->aio_lio_opcode != LIO_NOP) - { -#ifndef DONT_NEED_AIO_MISC_COND - waitlist->list[cnt].cond = NULL; -#endif - waitlist->list[cnt].result = NULL; - waitlist->list[cnt].next = requests[cnt]->waiting; - waitlist->list[cnt].counterp = &waitlist->counter; - waitlist->list[cnt].sigevp = &waitlist->sigev; - requests[cnt]->waiting = &waitlist->list[cnt]; - ++total; - } - } - - waitlist->counter = total; - waitlist->sigev = *sig; - } - } - - /* Release the mutex. */ - pthread_mutex_unlock (&__aio_requests_mutex); - - return result; -} - - -#if SHLIB_COMPAT (librt, GLIBC_2_1, GLIBC_2_4) -int -attribute_compat_text_section -__lio_listio_21 (int mode, struct aiocb *const list[], int nent, - struct sigevent *sig) -{ - /* Check arguments. */ - if (mode != LIO_WAIT && mode != LIO_NOWAIT) - { - __set_errno (EINVAL); - return -1; - } - - return lio_listio_internal (mode | LIO_NO_INDIVIDUAL_EVENT, list, nent, sig); -} -compat_symbol (librt, __lio_listio_21, lio_listio, GLIBC_2_1); -#endif - - -int -__lio_listio_item_notify (int mode, struct aiocb *const list[], int nent, - struct sigevent *sig) -{ - /* Check arguments. */ - if (mode != LIO_WAIT && mode != LIO_NOWAIT) - { - __set_errno (EINVAL); - return -1; - } - return lio_listio_internal (mode, list, nent, sig); -} -versioned_symbol (librt, __lio_listio_item_notify, lio_listio, GLIBC_2_4); +#include -- cgit 1.4.1