diff options
author | Paul Mackerras <paulus@samba.org> | 2008-01-24 10:07:21 +1100 |
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committer | Paul Mackerras <paulus@samba.org> | 2008-01-24 10:07:21 +1100 |
commit | 9156ad48338e0306e508ead5c0d9986050744475 (patch) | |
tree | 37f3a90e38190052ecf3cdf9171dfdddd37b56fd /block | |
parent | fa28237cfcc5827553044cbd6ee52e33692b0faa (diff) | |
parent | 8f7b3d156d348b6766833cd4e272d0d19b501e64 (diff) |
Merge branch 'linux-2.6'
Diffstat (limited to 'block')
-rw-r--r-- | block/blktrace.c | 81 |
1 files changed, 3 insertions, 78 deletions
diff --git a/block/blktrace.c b/block/blktrace.c index 498a0a54a6a..9b4da4ae3c7 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -25,7 +25,6 @@ #include <linux/time.h> #include <asm/uaccess.h> -static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; static unsigned int blktrace_seq __read_mostly = 1; /* @@ -41,7 +40,7 @@ static void trace_note(struct blk_trace *bt, pid_t pid, int action, const int cpu = smp_processor_id(); t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; - t->time = cpu_clock(cpu) - per_cpu(blk_trace_cpu_offset, cpu); + t->time = ktime_to_ns(ktime_get()); t->device = bt->dev; t->action = action; t->pid = pid; @@ -159,7 +158,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; t->sequence = ++(*sequence); - t->time = cpu_clock(cpu) - per_cpu(blk_trace_cpu_offset, cpu); + t->time = ktime_to_ns(ktime_get()); t->sector = sector; t->bytes = bytes; t->action = what; @@ -179,7 +178,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, EXPORT_SYMBOL_GPL(__blk_add_trace); static struct dentry *blk_tree_root; -static struct mutex blk_tree_mutex; +static DEFINE_MUTEX(blk_tree_mutex); static unsigned int root_users; static inline void blk_remove_root(void) @@ -505,77 +504,3 @@ void blk_trace_shutdown(struct request_queue *q) blk_trace_remove(q); } } - -/* - * Average offset over two calls to cpu_clock() with a gettimeofday() - * in the middle - */ -static void blk_check_time(unsigned long long *t, int this_cpu) -{ - unsigned long long a, b; - struct timeval tv; - - a = cpu_clock(this_cpu); - do_gettimeofday(&tv); - b = cpu_clock(this_cpu); - - *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; - *t -= (a + b) / 2; -} - -/* - * calibrate our inter-CPU timings - */ -static void blk_trace_check_cpu_time(void *data) -{ - unsigned long long *t; - int this_cpu = get_cpu(); - - t = &per_cpu(blk_trace_cpu_offset, this_cpu); - - /* - * Just call it twice, hopefully the second call will be cache hot - * and a little more precise - */ - blk_check_time(t, this_cpu); - blk_check_time(t, this_cpu); - - put_cpu(); -} - -static void blk_trace_set_ht_offsets(void) -{ -#if defined(CONFIG_SCHED_SMT) - int cpu, i; - - /* - * now make sure HT siblings have the same time offset - */ - preempt_disable(); - for_each_online_cpu(cpu) { - unsigned long long *cpu_off, *sibling_off; - - for_each_cpu_mask(i, per_cpu(cpu_sibling_map, cpu)) { - if (i == cpu) - continue; - - cpu_off = &per_cpu(blk_trace_cpu_offset, cpu); - sibling_off = &per_cpu(blk_trace_cpu_offset, i); - *sibling_off = *cpu_off; - } - } - preempt_enable(); -#endif -} - -static __init int blk_trace_init(void) -{ - mutex_init(&blk_tree_mutex); - on_each_cpu(blk_trace_check_cpu_time, NULL, 1, 1); - blk_trace_set_ht_offsets(); - - return 0; -} - -module_init(blk_trace_init); - |