The following commit has been merged into the timers/nohz branch of tip: Commit-ID: 7c805795307b40af50a45b7db44dd09ac1700947 Gitweb: https://git.kernel.org/tip/7c805795307b40af50a45b7db44dd09ac1700947 Author: Thomas Gleixner <tglx@xxxxxxxxxxxxx> AuthorDate: Wed, 23 Oct 2019 14:27:14 +02:00 Committer: Frederic Weisbecker <frederic@xxxxxxxxxx> CommitterDate: Fri, 14 Feb 2020 16:04:35 +01:00 x86/entry: Remove _TIF_NOHZ from _TIF_WORK_SYSCALL_ENTRY Evaluating _TIF_NOHZ to decide whether to use the slow syscall entry path is not only pointless, it's actually counterproductive: 1) Context tracking code is invoked unconditionally before that flag is evaluated. 2) If the flag is set the slow path is invoked for nothing due to #1 Remove it. Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Signed-off-by: Frederic Weisbecker <frederic@xxxxxxxxxx> --- arch/x86/include/asm/thread_info.h | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index cf43279..6cb9d1b 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -133,14 +133,10 @@ struct thread_info { #define _TIF_X32 (1 << TIF_X32) #define _TIF_FSCHECK (1 << TIF_FSCHECK) -/* - * work to do in syscall_trace_enter(). Also includes TIF_NOHZ for - * enter_from_user_mode() - */ +/* Work to do before invoking the actual syscall. */ #define _TIF_WORK_SYSCALL_ENTRY \ (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_EMU | _TIF_SYSCALL_AUDIT | \ - _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \ - _TIF_NOHZ) + _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT) /* flags to check in __switch_to() */ #define _TIF_WORK_CTXSW_BASE \
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