Le 14/03/2020 à 00:56, Alistair Francis a écrit :
> Add support for host and target futex_time64. If futex_time64 exists on
> the host we try that first before falling back to the standard futux
> syscall.
>
> Signed-off-by: Alistair Francis <alistair.fran...@wdc.com>
> ---
> linux-user/syscall.c | 144 +++++++++++++++++++++++++++++++++++++++----
> 1 file changed, 131 insertions(+), 13 deletions(-)
>
> diff --git a/linux-user/syscall.c b/linux-user/syscall.c
> index 60fd775d9c..b3bfb02688 100644
> --- a/linux-user/syscall.c
> +++ b/linux-user/syscall.c
> @@ -245,7 +245,12 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4
> arg4,type5 arg5, \
> #define __NR_sys_rt_sigqueueinfo __NR_rt_sigqueueinfo
> #define __NR_sys_rt_tgsigqueueinfo __NR_rt_tgsigqueueinfo
> #define __NR_sys_syslog __NR_syslog
> -#define __NR_sys_futex __NR_futex
> +#if defined(__NR_futex)
> +# define __NR_sys_futex __NR_futex
> +#endif
> +#if defined(__NR_futex_time64)
> +# define __NR_sys_futex_time64 __NR_futex_time64
> +#endif
> #define __NR_sys_inotify_init __NR_inotify_init
> #define __NR_sys_inotify_add_watch __NR_inotify_add_watch
> #define __NR_sys_inotify_rm_watch __NR_inotify_rm_watch
> @@ -295,10 +300,16 @@ _syscall1(int,exit_group,int,error_code)
> #if defined(TARGET_NR_set_tid_address) && defined(__NR_set_tid_address)
> _syscall1(int,set_tid_address,int *,tidptr)
> #endif
> -#if defined(TARGET_NR_futex) && defined(__NR_futex)
> +#if (defined(TARGET_NR_futex) && defined(__NR_futex)) || \
> + (defined(TARGET_NR_futex_time64) && \
> + (HOST_LONG_BITS == 64 && defined(__NR_futex)))
> _syscall6(int,sys_futex,int *,uaddr,int,op,int,val,
> const struct timespec *,timeout,int *,uaddr2,int,val3)
> #endif
> +#if (defined(TARGET_NR_futex_time64) && defined(__NR_futex_teim64))
> +_syscall6(int,sys_futex_time64,int *,uaddr,int,op,int,val,
> + const struct timespec *,timeout,int *,uaddr2,int,val3)
> +#endif
> #define __NR_sys_sched_getaffinity __NR_sched_getaffinity
> _syscall3(int, sys_sched_getaffinity, pid_t, pid, unsigned int, len,
> unsigned long *, user_mask_ptr);
> @@ -762,10 +773,14 @@ safe_syscall5(int, ppoll, struct pollfd *, ufds,
> unsigned int, nfds,
> safe_syscall6(int, epoll_pwait, int, epfd, struct epoll_event *, events,
> int, maxevents, int, timeout, const sigset_t *, sigmask,
> size_t, sigsetsize)
> -#ifdef TARGET_NR_futex
> +#if defined(__NR_futex)
> safe_syscall6(int,futex,int *,uaddr,int,op,int,val, \
> const struct timespec *,timeout,int *,uaddr2,int,val3)
> #endif
> +#if defined(__NR_futex_time64)
> +safe_syscall6(int,futex_time64,int *,uaddr,int,op,int,val, \
> + const struct timespec *,timeout,int *,uaddr2,int,val3)
> +#endif
> safe_syscall2(int, rt_sigsuspend, sigset_t *, newset, size_t, sigsetsize)
> safe_syscall2(int, kill, pid_t, pid, int, sig)
> safe_syscall2(int, tkill, int, tid, int, sig)
> @@ -1229,7 +1244,7 @@ static inline abi_long target_to_host_timespec(struct
> timespec *host_ts,
> }
> #endif
>
> -#if defined(TARGET_NR_clock_settime64)
> +#if defined(TARGET_NR_clock_settime64) || defined(TARGET_NR_futex_time64)
> static inline abi_long target_to_host_timespec64(struct timespec *host_ts,
> abi_ulong target_addr)
> {
> @@ -6890,6 +6905,55 @@ static inline abi_long host_to_target_statx(struct
> target_statx *host_stx,
> }
> #endif
>
> +static int do_sys_futex(int *uaddr, int op, int val,
> + const struct timespec *timeout, int *uaddr2,
> + int val3)
> +{
> +#if HOST_LONG_BITS == 64
> +#if defined(__NR_futex)
> + /* always a 64-bit time_t, it doesn't define _time64 version */
> + return sys_futex(uaddr, op, val, timeout, uaddr2, val3);
> +
> +#endif
> +#else /* HOST_LONG_BITS == 64 */
> +#if defined(__NR_futex_time64)
> + if (sizeof(timeout->tv_sec) == 8) {
> + /* _time64 function on 32bit arch */
> + return sys_futex_time64(uaddr, op, val, timeout, uaddr2, val3);
> + }
> +#endif
> +#if defined(__NR_futex)
> + /* old function on 32bit arch */
> + return sys_futex(uaddr, op, val, timeout, uaddr2, val3);
> +#endif
> +#endif /* HOST_LONG_BITS == 64 */
> + g_assert_not_reached();
> +}
> +
> +static int do_safe_futex(int *uaddr, int op, int val,
> + const struct timespec *timeout, int *uaddr2,
> + int val3)
> +{
> +#if HOST_LONG_BITS == 64
> +#if defined(__NR_futex)
> + /* always a 64-bit time_t, it doesn't define _time64 version */
> + return get_errno(safe_futex(uaddr, op, val, timeout, uaddr2, val3));
> +#endif
> +#else /* HOST_LONG_BITS == 64 */
> +#if defined(__NR_futex_time64)
> + if (sizeof(timeout->tv_sec) == 8) {
> + /* _time64 function on 32bit arch */
> + return get_errno(safe_futex_time64(uaddr, op, val, timeout, uaddr2,
> + val3));
> + }
> +#endif
> +#if defined(__NR_futex)
> + /* old function on 32bit arch */
> + return get_errno(safe_futex(uaddr, op, val, timeout, uaddr2, val3));
> +#endif
> +#endif /* HOST_LONG_BITS == 64 */
> + return -TARGET_ENOSYS;
> +}
>
> /* ??? Using host futex calls even when target atomic operations
> are not really atomic probably breaks things. However implementing
> @@ -6919,12 +6983,61 @@ static int do_futex(target_ulong uaddr, int op, int
> val, target_ulong timeout,
> } else {
> pts = NULL;
> }
> - return get_errno(safe_futex(g2h(uaddr), op, tswap32(val),
> + return get_errno(do_safe_futex(g2h(uaddr), op, tswap32(val),
> + pts, NULL, val3));
> + case FUTEX_WAKE:
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> + case FUTEX_FD:
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> + case FUTEX_REQUEUE:
> + case FUTEX_CMP_REQUEUE:
> + case FUTEX_WAKE_OP:
> + /* For FUTEX_REQUEUE, FUTEX_CMP_REQUEUE, and FUTEX_WAKE_OP, the
> + TIMEOUT parameter is interpreted as a uint32_t by the kernel.
> + But the prototype takes a `struct timespec *'; insert casts
> + to satisfy the compiler. We do not need to tswap TIMEOUT
> + since it's not compared to guest memory. */
> + pts = (struct timespec *)(uintptr_t) timeout;
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, pts,
> + g2h(uaddr2),
> + (base_op == FUTEX_CMP_REQUEUE
> + ? tswap32(val3)
> + : val3)));
> + default:
> + return -TARGET_ENOSYS;
> + }
> +}
> +#endif
> +
> +#if defined(TARGET_NR_futex_time64)
> +static int do_futex_time64(target_ulong uaddr, int op, int val, target_ulong
> timeout,
> + target_ulong uaddr2, int val3)
> +{
> + struct timespec ts, *pts;
> + int base_op;
> +
> + /* ??? We assume FUTEX_* constants are the same on both host
> + and target. */
> +#ifdef FUTEX_CMD_MASK
> + base_op = op & FUTEX_CMD_MASK;
> +#else
> + base_op = op;
> +#endif
> + switch (base_op) {
> + case FUTEX_WAIT:
> + case FUTEX_WAIT_BITSET:
> + if (timeout) {
> + pts = &ts;
> + target_to_host_timespec64(pts, timeout);
> + } else {
> + pts = NULL;
> + }
> + return get_errno(do_safe_futex(g2h(uaddr), op, tswap32(val),
> pts, NULL, val3));
> case FUTEX_WAKE:
> - return get_errno(safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> case FUTEX_FD:
> - return get_errno(safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, NULL, NULL, 0));
> case FUTEX_REQUEUE:
> case FUTEX_CMP_REQUEUE:
> case FUTEX_WAKE_OP:
> @@ -6934,16 +7047,17 @@ static int do_futex(target_ulong uaddr, int op, int
> val, target_ulong timeout,
> to satisfy the compiler. We do not need to tswap TIMEOUT
> since it's not compared to guest memory. */
> pts = (struct timespec *)(uintptr_t) timeout;
> - return get_errno(safe_futex(g2h(uaddr), op, val, pts,
> - g2h(uaddr2),
> - (base_op == FUTEX_CMP_REQUEUE
> - ? tswap32(val3)
> - : val3)));
> + return get_errno(do_safe_futex(g2h(uaddr), op, val, pts,
> + g2h(uaddr2),
> + (base_op == FUTEX_CMP_REQUEUE
> + ? tswap32(val3)
> + : val3)));
> default:
> return -TARGET_ENOSYS;
> }
> }
> #endif
> +
> #if defined(TARGET_NR_name_to_handle_at) && defined(CONFIG_OPEN_BY_HANDLE)
> static abi_long do_name_to_handle_at(abi_long dirfd, abi_long pathname,
> abi_long handle, abi_long mount_id,
> @@ -7505,7 +7619,7 @@ static abi_long do_syscall1(void *cpu_env, int num,
> abi_long arg1,
> ts = cpu->opaque;
> if (ts->child_tidptr) {
> put_user_u32(0, ts->child_tidptr);
> - sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX,
> + do_sys_futex(g2h(ts->child_tidptr), FUTEX_WAKE, INT_MAX,
> NULL, NULL, 0);
> }
> thread_cpu = NULL;
> @@ -11597,6 +11711,10 @@ static abi_long do_syscall1(void *cpu_env, int num,
> abi_long arg1,
> case TARGET_NR_futex:
> return do_futex(arg1, arg2, arg3, arg4, arg5, arg6);
> #endif
> +#ifdef TARGET_NR_futex_time64
> + case TARGET_NR_futex_time64:
> + return do_futex_time64(arg1, arg2, arg3, arg4, arg5, arg6);
> +#endif
> #if defined(TARGET_NR_inotify_init) && defined(__NR_inotify_init)
> case TARGET_NR_inotify_init:
> ret = get_errno(sys_inotify_init());
>
Reviewed-by: Laurent Vivier <laur...@vivier.eu>
