5 #include <linux/module.h>
6 #include <linux/proc_fs.h>
7 #include <linux/sched.h>
8 #include <linux/timex.h>
9 #include <linux/marker.h>
10 #include <asm/ptrace.h>
11 #include <asm/system.h>
13 static void pmc_flush_cache(void)
15 /* write back and invalidate cache (a serializing instruction) */
17 __asm__
__volatile__ ( "wbinvd" : : : "memory" );
19 /* The wbinvd instruction does not wait for the external caches
20 * to be flushed, but only requests that it be done. The loop
21 * is to be sure that enough time has elapsed, but the compiler
22 * might simplify or even remove it. The loop bound is for a
23 * 512 KB L2 cache. On a Pentium Pro/II/III, the loop uses
24 * 2 cycles per iteration.
26 * Does wbinvd also cause the TLB to be flushed?
27 * A comment in mtrr.c suggests that it does.
29 { register int i
; for (i
= 0; i
< 512*1024; i
++) { } }
33 static void noinline
test2(const struct marker
*mdata
,
34 void *call_private
, ...)
36 unsigned char *ins
= __builtin_return_address(0) - 5;
39 printk("ip %p\n", __builtin_return_address(0));
40 printk("prev_ins %hX %hX %hX %hX %hX\n",
41 ins
[0], ins
[1], ins
[2], ins
[3], ins
[4]);
51 * Generic marker flavor always available.
52 * Note : the empty asm volatile with read constraint is used here instead of a
53 * "used" attribute to fix a gcc 4.1.x bug.
54 * Make sure the alignment of the structure in the __markers section will
55 * not add unwanted padding between the beginning of the section and the
56 * structure. Force alignment to the same alignment as the section start.
58 #define __my_trace_mark(generic, name, call_private, format, args...) \
60 static const char __mstrtab_##name[] \
61 __attribute__((section("__markers_strings"))) \
62 = #name "\0" format; \
63 static struct marker __mark_##name \
64 __attribute__((section("__markers"), aligned(8))) = \
65 { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \
66 0, 0, marker_probe_cb, \
67 { __mark_empty_function, NULL}, NULL }; \
68 __mark_check_format(format, ## args); \
70 if (unlikely(imv_read(__mark_##name.state))) \
72 (&__mark_##name, call_private, \
75 if (unlikely(_imv_read(__mark_##name.state))) \
77 (&__mark_##name, call_private, \
82 struct proc_dir_entry
*pentry
= NULL
;
84 static inline void test(unsigned long arg
, unsigned long arg2
)
90 temp
[2] = (temp
[0] + 60) << 10;
91 temp
[3] = (temp
[2] + 60) << 10;
92 temp
[4] = (temp
[3] + 60) << 10;
93 temp
[0] = (temp
[4] + 60) << 10;
95 //__my_trace_mark(1, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
97 test2(NULL
, NULL
, 2, 10, arg
, arg2
);
98 barrier(); // make sure the compiler does not optimize marker conditions away!
99 //__my_trace_mark(0, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2);
102 static int my_open(struct inode
*inode
, struct file
*file
)
105 cycles_t cycles1
, cycles2
;
108 local_irq_save(flags
);
110 pmc_flush_cache(); /* initial write back, without cycle count */
111 msleep(20); /* wait for L2 flush */
114 cycles1
= get_cycles();
116 for(i
=0; i
<2000; i
++) {
129 cycles2
= get_cycles();
131 local_irq_restore(flags
);
132 printk("cycles : %llu\n", cycles2
-cycles1
);
137 static struct file_operations my_operations
= {
141 int init_module(void)
143 pentry
= create_proc_entry("testmark", 0444, NULL
);
145 pentry
->proc_fops
= &my_operations
;
150 void cleanup_module(void)
152 remove_proc_entry("testmark", NULL
);
155 MODULE_LICENSE("GPL");
156 MODULE_AUTHOR("Mathieu Desnoyers");
157 MODULE_DESCRIPTION("Marker Test");
158 MODULE_VERSION("1.0");