diff mbox series

[13/18] linux: Only use 64-bit syscall if required for mq_timedreceive

Message ID 20210617115104.1359598-14-adhemerval.zanella@linaro.org
State Committed
Headers
Series More y2038 fixes |

Checks

Context Check Description
dj/TryBot-apply_patch success Patch applied to master at the time it was sent

Commit Message

Adhemerval Zanella June 17, 2021, 11:50 a.m. UTC 
  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.
---
 rt/Makefile                               |  4 +-
 rt/tst-mqueue10-time64.c                  |  1 +
 rt/tst-mqueue10.c                         | 62 +++++++++++++++++++++++
 sysdeps/unix/sysv/linux/mq_timedreceive.c | 35 +++++++------
 4 files changed, 85 insertions(+), 17 deletions(-)
 create mode 100644 rt/tst-mqueue10-time64.c
 create mode 100644 rt/tst-mqueue10.c

Comments

Lukasz Majewski June 21, 2021, 7:44 a.m. UTC | #1 
On Thu, 17 Jun 2021 08:50:59 -0300
Adhemerval Zanella <adhemerval.zanella@linaro.org> wrote:

> 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.
> ---
>  rt/Makefile                               |  4 +-
>  rt/tst-mqueue10-time64.c                  |  1 +
>  rt/tst-mqueue10.c                         | 62
> +++++++++++++++++++++++ sysdeps/unix/sysv/linux/mq_timedreceive.c |
> 35 +++++++------ 4 files changed, 85 insertions(+), 17 deletions(-)
>  create mode 100644 rt/tst-mqueue10-time64.c
>  create mode 100644 rt/tst-mqueue10.c
> 
> diff --git a/rt/Makefile b/rt/Makefile
> index 797f2da51e..3382c7a1d2 100644
> --- a/rt/Makefile
> +++ b/rt/Makefile
> @@ -48,7 +48,8 @@ tests := tst-shm tst-timer tst-timer2 \
>  	 tst-mqueue5 tst-mqueue6 tst-mqueue7 tst-mqueue8 tst-mqueue9
> \ tst-timer3 tst-timer4 tst-timer5 \
>  	 tst-cpuclock2 tst-cputimer1 tst-cputimer2 tst-cputimer3 \
> -	 tst-shm-cancel
> +	 tst-shm-cancel \
> +	 tst-mqueue10
>  tests-internal := tst-timer-sigmask
>  
>  tests-time64 := \
> @@ -58,6 +59,7 @@ tests-time64 := \
>    tst-mqueue2-time64 \
>    tst-mqueue4-time64 \
>    tst-mqueue8-time64 \
> +  tst-mqueue10-time64 \
>    tst-timer4-time64
>  
>  extra-libs := librt
> diff --git a/rt/tst-mqueue10-time64.c b/rt/tst-mqueue10-time64.c
> new file mode 100644
> index 0000000000..2c8a4ae372
> --- /dev/null
> +++ b/rt/tst-mqueue10-time64.c
> @@ -0,0 +1 @@
> +#include "tst-mqueue10.c"
> diff --git a/rt/tst-mqueue10.c b/rt/tst-mqueue10.c
> new file mode 100644
> index 0000000000..7fb53a1cae
> --- /dev/null
> +++ b/rt/tst-mqueue10.c
> @@ -0,0 +1,62 @@
> +/* Check for large timeout with mq_timedsend and mq_timedreceive.
> +   Copyright (C) 2021 Free Software Foundation, Inc.
> +   This file is part of the GNU C Library.
> +
> +   The GNU C Library is free software; you can redistribute it and/or
> +   modify it under the terms of the GNU Lesser General Public
> +   License as published by the Free Software Foundation; either
> +   version 2.1 of the License, or (at your option) any later version.
> +
> +   The GNU C Library is distributed in the hope that it will be
> useful,
> +   but WITHOUT ANY WARRANTY; without even the implied warranty of
> +   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
> +   Lesser General Public License for more details.
> +
> +   You should have received a copy of the GNU Lesser General Public
> +   License along with the GNU C Library; if not, see
> +   <https://www.gnu.org/licenses/>.  */
> +
> +#include <errno.h>
> +#include <intprops.h>
> +#include <mqueue.h>
> +#include <stdio.h>
> +#include <support/check.h>
> +#include <support/support.h>
> +#include <support/temp_file.h>
> +#include <unistd.h>
> +
> +static char name[sizeof "/tst-mqueue2-" + INT_BUFSIZE_BOUND (pid_t)];
> +
> +static void
> +do_cleanup (void)
> +{
> +  mq_unlink (name);
> +}
> +#define CLEANUP_HANDLER	do_cleanup
> +
> +static int
> +do_test (void)
> +{
> +  snprintf (name, sizeof (name), "/tst-mqueue2-%u", getpid ());
> +
> +  char msg[8] = { 0x55 };
> +
> +  struct mq_attr attr = { .mq_maxmsg = 1, .mq_msgsize = sizeof (msg)
> };
> +  mqd_t q = mq_open (name, O_CREAT | O_EXCL | O_RDWR, 0600, &attr);
> +  TEST_VERIFY_EXIT (q != (mqd_t) -1);
> +
> +  struct timespec ts = { TYPE_MAXIMUM (time_t), 0 };
> +
> +  {
> +    timer_t timer = support_create_timer (0, 100000000, false, NULL);
> +    TEST_COMPARE (mq_timedreceive (q, msg, sizeof (msg), NULL, &ts),
> -1);
> +    TEST_VERIFY (errno == EINTR || errno == EOVERFLOW);
> +    support_delete_timer (timer);
> +  }
> +
> +  mq_unlink (name);
> +
> +  return 0;
> +}
> +
> +#include <support/test-driver.c>
> diff --git a/sysdeps/unix/sysv/linux/mq_timedreceive.c
> b/sysdeps/unix/sysv/linux/mq_timedreceive.c index
> eb948ccc18..8776977daf 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 is32bit = abs_timeout != NULL
> +		 ? in_time_t_range (abs_timeout->tv_sec) : true;
> +  if (!is32bit)
> +    {
> +      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

Reviewed-by: Lukasz Majewski <lukma@denx.de>


Best regards,

Lukasz Majewski

--

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-59 Fax: (+49)-8142-66989-80 Email: lukma@denx.de
diff mbox series

Patch

diff --git a/rt/Makefile b/rt/Makefile
index 797f2da51e..3382c7a1d2 100644
--- a/rt/Makefile
+++ b/rt/Makefile
@@ -48,7 +48,8 @@  tests := tst-shm tst-timer tst-timer2 \
 	 tst-mqueue5 tst-mqueue6 tst-mqueue7 tst-mqueue8 tst-mqueue9 \
 	 tst-timer3 tst-timer4 tst-timer5 \
 	 tst-cpuclock2 tst-cputimer1 tst-cputimer2 tst-cputimer3 \
-	 tst-shm-cancel
+	 tst-shm-cancel \
+	 tst-mqueue10
 tests-internal := tst-timer-sigmask
 
 tests-time64 := \
@@ -58,6 +59,7 @@  tests-time64 := \
   tst-mqueue2-time64 \
   tst-mqueue4-time64 \
   tst-mqueue8-time64 \
+  tst-mqueue10-time64 \
   tst-timer4-time64
 
 extra-libs := librt
diff --git a/rt/tst-mqueue10-time64.c b/rt/tst-mqueue10-time64.c
new file mode 100644
index 0000000000..2c8a4ae372
--- /dev/null
+++ b/rt/tst-mqueue10-time64.c
@@ -0,0 +1 @@ 
+#include "tst-mqueue10.c"
diff --git a/rt/tst-mqueue10.c b/rt/tst-mqueue10.c
new file mode 100644
index 0000000000..7fb53a1cae
--- /dev/null
+++ b/rt/tst-mqueue10.c
@@ -0,0 +1,62 @@ 
+/* Check for large timeout with mq_timedsend and mq_timedreceive.
+   Copyright (C) 2021 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <errno.h>
+#include <intprops.h>
+#include <mqueue.h>
+#include <stdio.h>
+#include <support/check.h>
+#include <support/support.h>
+#include <support/temp_file.h>
+#include <unistd.h>
+
+static char name[sizeof "/tst-mqueue2-" + INT_BUFSIZE_BOUND (pid_t)];
+
+static void
+do_cleanup (void)
+{
+  mq_unlink (name);
+}
+#define CLEANUP_HANDLER	do_cleanup
+
+static int
+do_test (void)
+{
+  snprintf (name, sizeof (name), "/tst-mqueue2-%u", getpid ());
+
+  char msg[8] = { 0x55 };
+
+  struct mq_attr attr = { .mq_maxmsg = 1, .mq_msgsize = sizeof (msg) };
+  mqd_t q = mq_open (name, O_CREAT | O_EXCL | O_RDWR, 0600, &attr);
+  TEST_VERIFY_EXIT (q != (mqd_t) -1);
+
+  struct timespec ts = { TYPE_MAXIMUM (time_t), 0 };
+
+  {
+    timer_t timer = support_create_timer (0, 100000000, false, NULL);
+    TEST_COMPARE (mq_timedreceive (q, msg, sizeof (msg), NULL, &ts), -1);
+    TEST_VERIFY (errno == EINTR || errno == EOVERFLOW);
+    support_delete_timer (timer);
+  }
+
+  mq_unlink (name);
+
+  return 0;
+}
+
+#include <support/test-driver.c>
diff --git a/sysdeps/unix/sysv/linux/mq_timedreceive.c b/sysdeps/unix/sysv/linux/mq_timedreceive.c
index eb948ccc18..8776977daf 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 is32bit = abs_timeout != NULL
+		 ? in_time_t_range (abs_timeout->tv_sec) : true;
+  if (!is32bit)
+    {
+      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