diff options
Diffstat (limited to 'block/blktrace.c')
| -rw-r--r-- | block/blktrace.c | 53 |
1 files changed, 41 insertions, 12 deletions
diff --git a/block/blktrace.c b/block/blktrace.c index 135593c8e45b..d3679dd1d220 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -22,32 +22,60 @@ #include <linux/init.h> #include <linux/mutex.h> #include <linux/debugfs.h> +#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; /* - * Send out a notify for this process, if we haven't done so since a trace - * started + * Send out a notify message. */ -static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) +static void trace_note(struct blk_trace *bt, pid_t pid, int action, + const void *data, size_t len) { struct blk_io_trace *t; - t = relay_reserve(bt->rchan, sizeof(*t) + sizeof(tsk->comm)); + t = relay_reserve(bt->rchan, sizeof(*t) + len); if (t) { + const int cpu = smp_processor_id(); + t->magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; + t->time = sched_clock() - per_cpu(blk_trace_cpu_offset, cpu); t->device = bt->dev; - t->action = BLK_TC_ACT(BLK_TC_NOTIFY); - t->pid = tsk->pid; - t->cpu = smp_processor_id(); - t->pdu_len = sizeof(tsk->comm); - memcpy((void *) t + sizeof(*t), tsk->comm, t->pdu_len); - tsk->btrace_seq = blktrace_seq; + t->action = action; + t->pid = pid; + t->cpu = cpu; + t->pdu_len = len; + memcpy((void *) t + sizeof(*t), data, len); } } +/* + * Send out a notify for this process, if we haven't done so since a trace + * started + */ +static void trace_note_tsk(struct blk_trace *bt, struct task_struct *tsk) +{ + tsk->btrace_seq = blktrace_seq; + trace_note(bt, tsk->pid, BLK_TN_PROCESS, tsk->comm, sizeof(tsk->comm)); +} + +static void trace_note_time(struct blk_trace *bt) +{ + struct timespec now; + unsigned long flags; + u32 words[2]; + + getnstimeofday(&now); + words[0] = now.tv_sec; + words[1] = now.tv_nsec; + + local_irq_save(flags); + trace_note(bt, 0, BLK_TN_TIMESTAMP, words, sizeof(words)); + local_irq_restore(flags); +} + static int act_log_check(struct blk_trace *bt, u32 what, sector_t sector, pid_t pid) { @@ -366,8 +394,7 @@ err: if (bt) { if (bt->dropped_file) debugfs_remove(bt->dropped_file); - if (bt->sequence) - free_percpu(bt->sequence); + free_percpu(bt->sequence); if (bt->rchan) relay_close(bt->rchan); kfree(bt); @@ -394,6 +421,8 @@ static int blk_trace_startstop(request_queue_t *q, int start) blktrace_seq++; smp_mb(); bt->trace_state = Blktrace_running; + + trace_note_time(bt); ret = 0; } } else { |