Release 4.11 arch/x86/kernel/tracepoint.c

/*
 * Code for supporting irq vector tracepoints.
 *
 * Copyright (C) 2013 Seiji Aguchi <seiji.aguchi@hds.com>
 *
 */
#include <asm/hw_irq.h>
#include <asm/desc.h>
#include <linux/atomic.h>


atomic_t trace_idt_ctr = ATOMIC_INIT(0);

struct desc_ptr trace_idt_descr = { NR_VECTORS * 16 - 1,
				(unsigned long) trace_idt_table };

/* No need to be aligned, but done to keep all IDTs defined the same way. */

gate_desc trace_idt_table[NR_VECTORS] __page_aligned_bss;


static int trace_irq_vector_refcount;
static DEFINE_MUTEX(irq_vector_mutex);



static void set_trace_idt_ctr(int val)
{
	atomic_set(&trace_idt_ctr, val);
	/* Ensure the trace_idt_ctr is set before sending IPI */
	wmb();
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Seiji Aguchi
21
100.00%
1
100.00%
Total
21
100.00%
1
100.00%



static void switch_idt(void *arg)
{
	unsigned long flags;

	local_irq_save(flags);
	load_current_idt();
	local_irq_restore(flags);
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Steven Rostedt
14
51.85%
1
50.00%
Seiji Aguchi
13
48.15%
1
50.00%
Total
27
100.00%
2
100.00%



int trace_irq_vector_regfunc(void)
{
	mutex_lock(&irq_vector_mutex);
	if (!trace_irq_vector_refcount) {
		set_trace_idt_ctr(1);
		smp_call_function(switch_idt, NULL, 0);
		switch_idt(NULL);
	}
	trace_irq_vector_refcount++;
	mutex_unlock(&irq_vector_mutex);
	return 0;
}

Contributors
Person
Tokens
Prop
Commits
CommitProp
Seiji Aguchi
47
92.16%
1
50.00%
Steven Rostedt
4
7.84%
1
50.00%
Total
51
100.00%
2
100.00%



void trace_irq_vector_unregfunc(void)
{
	mutex_lock(&irq_vector_mutex);
	trace_irq_vector_refcount--;
	if (!trace_irq_vector_refcount) {
		set_trace_idt_ctr(0);
		smp_call_function(switch_idt, NULL, 0);
		switch_idt(NULL);
	}
	mutex_unlock(&irq_vector_mutex);
}
Contributors
Person
Tokens
Prop
Commits
CommitProp
Seiji Aguchi
48
100.00%
1
100.00%
Total
48
100.00%
1
100.00%

Overall Contributors
Person
Tokens
Prop
Commits
CommitProp
Seiji Aguchi
181
90.05%
1
25.00%
Steven Rostedt
18
8.96%
2
50.00%
Kees Cook
2
1.00%
1
25.00%
Total
201
100.00%
4
100.00%
Directory: arch/x86/kernel

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.