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0ad6e3c519
___preempt_schedule() does SAVE_ALL/RESTORE_ALL but this is suboptimal, we do not need to save/restore the callee-saved register. And we already have arch/x86/lib/thunk_*.S which implements the similar asm wrappers, so it makes sense to redefine ___preempt_schedule() as "THUNK ..." and remove preempt.S altogether. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Reviewed-by: Andy Lutomirski <luto@amacapital.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20140921184153.GA23727@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
56 lines
1.3 KiB
ArmAsm
56 lines
1.3 KiB
ArmAsm
/*
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* Save registers before calling assembly functions. This avoids
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* disturbance of register allocation in some inline assembly constructs.
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* Copyright 2001,2002 by Andi Kleen, SuSE Labs.
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* Added trace_hardirqs callers - Copyright 2007 Steven Rostedt, Red Hat, Inc.
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* Subject to the GNU public license, v.2. No warranty of any kind.
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*/
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#include <linux/linkage.h>
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#include <asm/dwarf2.h>
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#include <asm/calling.h>
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#include <asm/asm.h>
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/* rdi: arg1 ... normal C conventions. rax is saved/restored. */
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.macro THUNK name, func, put_ret_addr_in_rdi=0
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.globl \name
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\name:
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CFI_STARTPROC
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/* this one pushes 9 elems, the next one would be %rIP */
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SAVE_ARGS
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.if \put_ret_addr_in_rdi
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movq_cfi_restore 9*8, rdi
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.endif
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call \func
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jmp restore
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CFI_ENDPROC
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_ASM_NOKPROBE(\name)
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.endm
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#ifdef CONFIG_TRACE_IRQFLAGS
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THUNK trace_hardirqs_on_thunk,trace_hardirqs_on_caller,1
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THUNK trace_hardirqs_off_thunk,trace_hardirqs_off_caller,1
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#endif
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#ifdef CONFIG_DEBUG_LOCK_ALLOC
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THUNK lockdep_sys_exit_thunk,lockdep_sys_exit
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#endif
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#ifdef CONFIG_PREEMPT
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THUNK ___preempt_schedule, preempt_schedule
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#ifdef CONFIG_CONTEXT_TRACKING
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THUNK ___preempt_schedule_context, preempt_schedule_context
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#endif
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#endif
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/* SAVE_ARGS below is used only for the .cfi directives it contains. */
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CFI_STARTPROC
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SAVE_ARGS
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restore:
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RESTORE_ARGS
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ret
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CFI_ENDPROC
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_ASM_NOKPROBE(restore)
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