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	We are going to split <linux/sched/task_stack.h> out of <linux/sched.h>, which will have to be picked up from other headers and a couple of .c files. Create a trivial placeholder <linux/sched/task_stack.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
		
			
				
	
	
		
			70 lines
		
	
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			70 lines
		
	
	
	
		
			1.8 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
/*
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 * Linux performance counter support for MIPS.
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 *
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 * Copyright (C) 2010 MIPS Technologies, Inc.
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 * Author: Deng-Cheng Zhu
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 *
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 * This code is based on the implementation for ARM, which is in turn
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 * based on the sparc64 perf event code and the x86 code. Performance
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 * counter access is based on the MIPS Oprofile code. And the callchain
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 * support references the code of MIPS stacktrace.c.
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 *
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 * This program is free software; you can redistribute it and/or modify
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 * it under the terms of the GNU General Public License version 2 as
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 * published by the Free Software Foundation.
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 */
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#include <linux/perf_event.h>
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#include <linux/sched/task_stack.h>
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#include <asm/stacktrace.h>
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/* Callchain handling code. */
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/*
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 * Leave userspace callchain empty for now. When we find a way to trace
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 * the user stack callchains, we will add it here.
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 */
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static void save_raw_perf_callchain(struct perf_callchain_entry_ctx *entry,
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				    unsigned long reg29)
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{
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	unsigned long *sp = (unsigned long *)reg29;
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	unsigned long addr;
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	while (!kstack_end(sp)) {
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		addr = *sp++;
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		if (__kernel_text_address(addr)) {
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			perf_callchain_store(entry, addr);
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			if (entry->nr >= entry->max_stack)
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				break;
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		}
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	}
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}
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void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
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			   struct pt_regs *regs)
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{
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	unsigned long sp = regs->regs[29];
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#ifdef CONFIG_KALLSYMS
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	unsigned long ra = regs->regs[31];
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	unsigned long pc = regs->cp0_epc;
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	if (raw_show_trace || !__kernel_text_address(pc)) {
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		unsigned long stack_page =
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			(unsigned long)task_stack_page(current);
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		if (stack_page && sp >= stack_page &&
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		    sp <= stack_page + THREAD_SIZE - 32)
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			save_raw_perf_callchain(entry, sp);
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		return;
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	}
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	do {
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		perf_callchain_store(entry, pc);
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		if (entry->nr >= entry->max_stack)
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			break;
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		pc = unwind_stack(current, &sp, pc, &ra);
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	} while (pc);
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#else
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	save_raw_perf_callchain(entry, sp);
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#endif
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}
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