Commit 320a4fc2 authored by Frederic Weisbecker's avatar Frederic Weisbecker
Browse files

arm64: Remove TIF_NOHZ 



The syscall slow path is spuriously invoked when context tracking is
activated while the entry code calls context tracking from fast path.

Remove that overhead and the unused flag itself while at it.

Acked-by: default avatarWill Deacon <will@kernel.org>
Signed-off-by: default avatarFrederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
parent 1acb2249

arch/arm64/Kconfig

+0 −1
Original line number Diff line number Diff line
@@ -140,7 +140,6 @@ config ARM64 
	select HAVE_CMPXCHG_DOUBLE

	select HAVE_CMPXCHG_LOCAL

	select HAVE_CONTEXT_TRACKING

	select HAVE_TIF_NOHZ

	select HAVE_COPY_THREAD_TLS

	select HAVE_DEBUG_BUGVERBOSE

	select HAVE_DEBUG_KMEMLEAK

arch/arm64/include/asm/thread_info.h

+1 −3
Original line number Diff line number Diff line
@@ -63,7 +63,6 @@ void arch_release_task_struct(struct task_struct *tsk); 
#define TIF_FOREIGN_FPSTATE	3	/* CPU's FP state is not current's */

#define TIF_UPROBE		4	/* uprobe breakpoint or singlestep */

#define TIF_FSCHECK		5	/* Check FS is USER_DS on return */

#define TIF_NOHZ		7

#define TIF_SYSCALL_TRACE	8	/* syscall trace active */

#define TIF_SYSCALL_AUDIT	9	/* syscall auditing */

#define TIF_SYSCALL_TRACEPOINT	10	/* syscall tracepoint for ftrace */
@@ -83,7 +82,6 @@ void arch_release_task_struct(struct task_struct *tsk); 
#define _TIF_NEED_RESCHED	(1 << TIF_NEED_RESCHED)

#define _TIF_NOTIFY_RESUME	(1 << TIF_NOTIFY_RESUME)

#define _TIF_FOREIGN_FPSTATE	(1 << TIF_FOREIGN_FPSTATE)

#define _TIF_NOHZ		(1 << TIF_NOHZ)

#define _TIF_SYSCALL_TRACE	(1 << TIF_SYSCALL_TRACE)

#define _TIF_SYSCALL_AUDIT	(1 << TIF_SYSCALL_AUDIT)

#define _TIF_SYSCALL_TRACEPOINT	(1 << TIF_SYSCALL_TRACEPOINT)
@@ -100,7 +98,7 @@ void arch_release_task_struct(struct task_struct *tsk); 


#define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \

				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \

				 _TIF_NOHZ | _TIF_SYSCALL_EMU)

				 _TIF_SYSCALL_EMU)



#define INIT_THREAD_INFO(tsk)						\

{									\

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