X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=block%2Fblktrace.c;h=d3679dd1d2201785e91194415d01736a16af54bc;hb=refs%2Fheads%2Fvserver;hp=2b4ef2b89b8d74b376a2011b5455039fd3730e20;hpb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;p=linux-2.6.git diff --git a/block/blktrace.c b/block/blktrace.c index 2b4ef2b89..d3679dd1d 100644 --- a/block/blktrace.c +++ b/block/blktrace.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 2006 Jens Axboe + * Copyright (C) 2006 Jens Axboe * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -22,32 +22,60 @@ #include #include #include +#include #include 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) { @@ -69,7 +97,7 @@ static u32 ddir_act[2] __read_mostly = { BLK_TC_ACT(BLK_TC_READ), BLK_TC_ACT(BLK /* * Bio action bits of interest */ -static u32 bio_act[5] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC), 0, BLK_TC_ACT(BLK_TC_AHEAD) }; +static u32 bio_act[9] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_ACT(BLK_TC_SYNC), 0, BLK_TC_ACT(BLK_TC_AHEAD), 0, 0, 0, BLK_TC_ACT(BLK_TC_META) }; /* * More could be added as needed, taking care to increment the decrementer @@ -81,6 +109,8 @@ static u32 bio_act[5] __read_mostly = { 0, BLK_TC_ACT(BLK_TC_BARRIER), BLK_TC_AC (((rw) & (1 << BIO_RW_SYNC)) >> (BIO_RW_SYNC - 1)) #define trace_ahead_bit(rw) \ (((rw) & (1 << BIO_RW_AHEAD)) << (2 - BIO_RW_AHEAD)) +#define trace_meta_bit(rw) \ + (((rw) & (1 << BIO_RW_META)) >> (BIO_RW_META - 3)) /* * The worker for the various blk_add_trace*() types. Fills out a @@ -103,6 +133,7 @@ void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, what |= bio_act[trace_barrier_bit(rw)]; what |= bio_act[trace_sync_bit(rw)]; what |= bio_act[trace_ahead_bit(rw)]; + what |= bio_act[trace_meta_bit(rw)]; pid = tsk->pid; if (unlikely(act_log_check(bt, what, sector, pid))) @@ -363,8 +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); @@ -391,6 +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 { @@ -450,8 +482,10 @@ int blk_trace_ioctl(struct block_device *bdev, unsigned cmd, char __user *arg) **/ void blk_trace_shutdown(request_queue_t *q) { - blk_trace_startstop(q, 0); - blk_trace_remove(q); + if (q->blk_trace) { + blk_trace_startstop(q, 0); + blk_trace_remove(q); + } } /* @@ -471,6 +505,9 @@ static void blk_check_time(unsigned long long *t) *t -= (a + b) / 2; } +/* + * calibrate our inter-CPU timings + */ static void blk_trace_check_cpu_time(void *data) { unsigned long long *t; @@ -488,20 +525,6 @@ static void blk_trace_check_cpu_time(void *data) put_cpu(); } -/* - * Call blk_trace_check_cpu_time() on each CPU to calibrate our inter-CPU - * timings - */ -static void blk_trace_calibrate_offsets(void) -{ - unsigned long flags; - - smp_call_function(blk_trace_check_cpu_time, NULL, 1, 1); - local_irq_save(flags); - blk_trace_check_cpu_time(NULL); - local_irq_restore(flags); -} - static void blk_trace_set_ht_offsets(void) { #if defined(CONFIG_SCHED_SMT) @@ -530,7 +553,7 @@ static void blk_trace_set_ht_offsets(void) static __init int blk_trace_init(void) { mutex_init(&blk_tree_mutex); - blk_trace_calibrate_offsets(); + on_each_cpu(blk_trace_check_cpu_time, NULL, 1, 1); blk_trace_set_ht_offsets(); return 0;