From e9e912d3349d8caf3c40bc09370509724c72ac2f Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 15 Jun 2021 23:05:21 -0300 Subject: linux: Only use 64-bit syscall if required for mq_timedreceive For !__ASSUME_TIME64_SYSCALLS there is no need to issue a 64-bit syscall if the provided timeout fits in a 32-bit one. The 64-bit usage should be rare since the timeout is a relative one. Checked on i686-linux-gnu on a 4.15 kernel and on a 5.11 kernel (with and without --enable-kernel=5.1) and on x86_64-linux-gnu. Reviewed-by: Lukasz Majewski --- sysdeps/unix/sysv/linux/mq_timedreceive.c | 35 +++++++++++++++++-------------- 1 file changed, 19 insertions(+), 16 deletions(-) (limited to 'sysdeps/unix/sysv/linux') diff --git a/sysdeps/unix/sysv/linux/mq_timedreceive.c b/sysdeps/unix/sysv/linux/mq_timedreceive.c index eb948ccc18..1a7b7a9c11 100644 --- a/sysdeps/unix/sysv/linux/mq_timedreceive.c +++ b/sysdeps/unix/sysv/linux/mq_timedreceive.c @@ -29,30 +29,33 @@ __mq_timedreceive_time64 (mqd_t mqdes, char *__restrict msg_ptr, size_t msg_len, #ifndef __NR_mq_timedreceive_time64 # define __NR_mq_timedreceive_time64 __NR_mq_timedreceive #endif - int ret = SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len, - msg_prio, abs_timeout); -#ifndef __ASSUME_TIME64_SYSCALLS - if (ret == 0 || errno != ENOSYS) - return ret; +#ifdef __ASSUME_TIME64_SYSCALLS + return SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len, + msg_prio, abs_timeout); +#else + bool need_time64 = abs_timeout != NULL + && !in_time_t_range (abs_timeout->tv_sec); + if (need_time64) + { + int r = SYSCALL_CANCEL (mq_timedreceive_time64, mqdes, msg_ptr, msg_len, + msg_prio, abs_timeout); + if (r == 0 || errno != ENOSYS) + return r; + __set_errno (EOVERFLOW); + return -1; + } - struct timespec ts32; + struct timespec ts32, *pts32 = NULL; if (abs_timeout != NULL) { - if (! in_time_t_range (abs_timeout->tv_sec)) - { - __set_errno (EOVERFLOW); - return -1; - } - ts32 = valid_timespec64_to_timespec (*abs_timeout); + pts32 = &ts32; } - ret = SYSCALL_CANCEL (mq_timedreceive, mqdes, msg_ptr, msg_len, msg_prio, - abs_timeout != NULL ? &ts32 : NULL); + return SYSCALL_CANCEL (mq_timedreceive, mqdes, msg_ptr, msg_len, msg_prio, + pts32); #endif - - return ret; } #if __TIMESIZE != 64 -- cgit 1.4.1