| 1 | /* test-mark.c |
| 2 | * |
| 3 | */ |
| 4 | |
| 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> |
| 12 | |
| 13 | static void pmc_flush_cache(void) |
| 14 | { |
| 15 | register int i; |
| 16 | /* write back and invalidate cache (a serializing instruction) */ |
| 17 | |
| 18 | __asm__ __volatile__ ( "wbinvd" : : : "memory" ); |
| 19 | |
| 20 | /* The wbinvd instruction does not wait for the external caches |
| 21 | * to be flushed, but only requests that it be done. The loop |
| 22 | * is to be sure that enough time has elapsed, but the compiler |
| 23 | * might simplify or even remove it. The loop bound is for a |
| 24 | * 512 KB L2 cache. On a Pentium Pro/II/III, the loop uses |
| 25 | * 2 cycles per iteration. |
| 26 | * |
| 27 | * Does wbinvd also cause the TLB to be flushed? |
| 28 | * A comment in mtrr.c suggests that it does. |
| 29 | */ |
| 30 | for (i = 0; i < 512*1024; i++) { |
| 31 | cpu_relax(); |
| 32 | } |
| 33 | } |
| 34 | |
| 35 | static void noinline test2(const struct marker *mdata, |
| 36 | void *call_private, ...) |
| 37 | { |
| 38 | /* not called */ |
| 39 | printk("blah\n"); |
| 40 | } |
| 41 | |
| 42 | /* |
| 43 | * Generic marker flavor always available. |
| 44 | * Note : the empty asm volatile with read constraint is used here instead of a |
| 45 | * "used" attribute to fix a gcc 4.1.x bug. |
| 46 | * Make sure the alignment of the structure in the __markers section will |
| 47 | * not add unwanted padding between the beginning of the section and the |
| 48 | * structure. Force alignment to the same alignment as the section start. |
| 49 | */ |
| 50 | #define __my_trace_mark(generic, name, call_private, format, args...) \ |
| 51 | do { \ |
| 52 | static const char __mstrtab_##name[] \ |
| 53 | __attribute__((section("__markers_strings"))) \ |
| 54 | = #name "\0" format; \ |
| 55 | static struct marker __mark_##name \ |
| 56 | __attribute__((section("__markers"), aligned(8))) = \ |
| 57 | { __mstrtab_##name, &__mstrtab_##name[sizeof(#name)], \ |
| 58 | 0, 0, marker_probe_cb, \ |
| 59 | { __mark_empty_function, NULL}, NULL }; \ |
| 60 | __mark_check_format(format, ## args); \ |
| 61 | if (!generic) { \ |
| 62 | if (unlikely(imv_read(__mark_##name.state))) \ |
| 63 | test2 \ |
| 64 | (&__mark_##name, call_private, \ |
| 65 | ## args); \ |
| 66 | } else { \ |
| 67 | if (unlikely(_imv_read(__mark_##name.state))) \ |
| 68 | test2 \ |
| 69 | (&__mark_##name, call_private, \ |
| 70 | ## args); \ |
| 71 | } \ |
| 72 | } while (0) |
| 73 | |
| 74 | //asm volatile (""); |
| 75 | struct proc_dir_entry *pentry = NULL; |
| 76 | |
| 77 | static inline void test(unsigned long arg, unsigned long arg2) |
| 78 | { |
| 79 | volatile int temp[5]; |
| 80 | #ifdef CACHEFLUSH |
| 81 | pmc_flush_cache(); |
| 82 | #endif |
| 83 | temp[2] = (temp[0] + 60) << 10; |
| 84 | temp[3] = (temp[2] + 60) << 10; |
| 85 | temp[4] = (temp[3] + 60) << 10; |
| 86 | temp[0] = (temp[4] + 60) << 10; |
| 87 | //asm volatile (""); |
| 88 | barrier(); |
| 89 | __my_trace_mark(1, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2); |
| 90 | barrier(); |
| 91 | //__my_trace_mark(0, kernel_debug_test, NULL, "%d %d %ld %ld", 2, current->pid, arg, arg2); |
| 92 | } |
| 93 | |
| 94 | static int my_open(struct inode *inode, struct file *file) |
| 95 | { |
| 96 | unsigned int i; |
| 97 | cycles_t cycles1, cycles2; |
| 98 | unsigned long flags; |
| 99 | |
| 100 | local_irq_save(flags); |
| 101 | #ifdef CACHEFLUSH |
| 102 | pmc_flush_cache(); /* initial write back, without cycle count */ |
| 103 | msleep(20); /* wait for L2 flush */ |
| 104 | #endif |
| 105 | rdtsc_barrier(); |
| 106 | cycles1 = get_cycles(); |
| 107 | rdtsc_barrier(); |
| 108 | for(i=0; i<2000; i++) { |
| 109 | test(i, i); |
| 110 | test(i, i); |
| 111 | test(i, i); |
| 112 | test(i, i); |
| 113 | test(i, i); |
| 114 | test(i, i); |
| 115 | test(i, i); |
| 116 | test(i, i); |
| 117 | test(i, i); |
| 118 | test(i, i); |
| 119 | } |
| 120 | rdtsc_barrier(); |
| 121 | cycles2 = get_cycles(); |
| 122 | rdtsc_barrier(); |
| 123 | local_irq_restore(flags); |
| 124 | printk("cycles : %llu\n", cycles2-cycles1); |
| 125 | return -EPERM; |
| 126 | } |
| 127 | |
| 128 | |
| 129 | static struct file_operations my_operations = { |
| 130 | .open = my_open, |
| 131 | }; |
| 132 | |
| 133 | int init_module(void) |
| 134 | { |
| 135 | pentry = create_proc_entry("testmark", 0444, NULL); |
| 136 | if (pentry) |
| 137 | pentry->proc_fops = &my_operations; |
| 138 | |
| 139 | return 0; |
| 140 | } |
| 141 | |
| 142 | void cleanup_module(void) |
| 143 | { |
| 144 | remove_proc_entry("testmark", NULL); |
| 145 | } |
| 146 | |
| 147 | MODULE_LICENSE("GPL"); |
| 148 | MODULE_AUTHOR("Mathieu Desnoyers"); |
| 149 | MODULE_DESCRIPTION("Marker Test"); |
| 150 | MODULE_VERSION("1.0"); |