summaryrefslogtreecommitdiff
path: root/include/linux/futex.h
diff options
context:
space:
mode:
authorDominik Brodowski <linux@dominikbrodowski.net>2018-03-11 11:34:26 +0100
committerDominik Brodowski <linux@dominikbrodowski.net>2018-04-02 20:15:02 +0200
commit2de0db992de189fccc83fed57c30875144821491 (patch)
tree138ea29f99e5e5ebb4c304da1961cdf0731a8b36 /include/linux/futex.h
parent6b27aef09fea32b805a8c81287b1bb80362dadb0 (diff)
mm: use do_futex() instead of sys_futex() in mm_release()
sys_futex() is a wrapper to do_futex() which does not modify any values here: - uaddr, val and val3 are kept the same - op is masked with FUTEX_CMD_MASK, but is always set to FUTEX_WAKE. Therefore, val2 is always 0. - as utime is set to NULL, *timeout is NULL This patch is part of a series which removes in-kernel calls to syscalls. On this basis, the syscall entry path can be streamlined. For details, see http://lkml.kernel.org/r/20180325162527.GA17492@light.dominikbrodowski.net Cc: Ingo Molnar <mingo@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Darren Hart <dvhart@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net>
Diffstat (limited to 'include/linux/futex.h')
-rw-r--r--include/linux/futex.h13
1 files changed, 10 insertions, 3 deletions
diff --git a/include/linux/futex.h b/include/linux/futex.h
index c0fb9a24bbd2..821ae502d3d8 100644
--- a/include/linux/futex.h
+++ b/include/linux/futex.h
@@ -9,9 +9,6 @@ struct inode;
struct mm_struct;
struct task_struct;
-long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
- u32 __user *uaddr2, u32 val2, u32 val3);
-
extern int
handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi);
@@ -55,6 +52,9 @@ union futex_key {
#ifdef CONFIG_FUTEX
extern void exit_robust_list(struct task_struct *curr);
+
+long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
+ u32 __user *uaddr2, u32 val2, u32 val3);
#ifdef CONFIG_HAVE_FUTEX_CMPXCHG
#define futex_cmpxchg_enabled 1
#else
@@ -64,6 +64,13 @@ extern int futex_cmpxchg_enabled;
static inline void exit_robust_list(struct task_struct *curr)
{
}
+
+static inline long do_futex(u32 __user *uaddr, int op, u32 val,
+ ktime_t *timeout, u32 __user *uaddr2,
+ u32 val2, u32 val3)
+{
+ return -EINVAL;
+}
#endif
#ifdef CONFIG_FUTEX_PI