From: Jens Axboe Date: Thu, 1 Sep 2005 13:43:12 +0000 (+0200) Subject: [PATCH] Sync inter processor time X-Git-Tag: blktrace-0.99~226 X-Git-Url: https://git.kernel.dk/?a=commitdiff_plain;h=1c066f23e412a67f8f958447b80eb83f75557bdb;p=blktrace.git [PATCH] Sync inter processor time Calibrate the time offsets of each processor in an SMP system on boot time to attempt to keep the timestamps offsets in check. --- diff --git a/CHANGELOG b/CHANGELOG index 377369c..6fc87f4 100644 --- a/CHANGELOG +++ b/CHANGELOG @@ -1,3 +1,5 @@ +20050901: + - Update kernel patch 20050830: - Added argument parsing - Added action mask set up diff --git a/kernel/blk-trace-2.6.13-mm1-A0 b/kernel/blk-trace-2.6.13-mm1-A0 deleted file mode 100644 index 70e7356..0000000 --- a/kernel/blk-trace-2.6.13-mm1-A0 +++ /dev/null @@ -1,537 +0,0 @@ -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/blktrace.c linux-2.6.13-rc6-mm2/drivers/block/blktrace.c ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/blktrace.c 1970-01-01 01:00:00.000000000 +0100 -+++ linux-2.6.13-rc6-mm2/drivers/block/blktrace.c 2005-08-30 20:56:43.000000000 +0200 -@@ -0,0 +1,184 @@ -+#include -+#include -+#include -+#include -+#include -+#include -+#include -+ -+static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; -+ -+static inline unsigned long long blk_trace_cpu_time(void) -+{ -+ unsigned long long offset; -+ -+ offset = sched_clock() - per_cpu(blk_trace_cpu_offset, get_cpu()); -+ put_cpu(); -+ return offset; -+} -+ -+void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, -+ int rw, u32 what, int error, int pdu_len, char *pdu_data) -+{ -+ struct blk_io_trace t; -+ unsigned long flags; -+ -+ if (rw & (1 << BIO_RW_BARRIER)) -+ what |= BLK_TC_ACT(BLK_TC_BARRIER); -+ if (rw & (1 << BIO_RW_SYNC)) -+ what |= BLK_TC_ACT(BLK_TC_SYNC); -+ -+ if (rw & WRITE) -+ what |= BLK_TC_ACT(BLK_TC_WRITE); -+ else -+ what |= BLK_TC_ACT(BLK_TC_READ); -+ -+ if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) -+ return; -+ -+ t.magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; -+ t.sequence = atomic_add_return(1, &bt->sequence); -+ t.time = blk_trace_cpu_time(); -+ t.sector = sector; -+ t.bytes = bytes; -+ t.action = what; -+ t.pid = current->pid; -+ t.error = error; -+ t.pdu_len = pdu_len; -+ -+ local_irq_save(flags); -+ __relay_write(bt->rchan, &t, sizeof(t)); -+ if (pdu_len) -+ __relay_write(bt->rchan, pdu_data, pdu_len); -+ local_irq_restore(flags); -+} -+ -+int blk_stop_trace(struct block_device *bdev) -+{ -+ request_queue_t *q = bdev_get_queue(bdev); -+ struct blk_trace *bt = NULL; -+ int ret = -EINVAL; -+ -+ if (!q) -+ return -ENXIO; -+ -+ down(&bdev->bd_sem); -+ -+ spin_lock_irq(q->queue_lock); -+ if (q->blk_trace) { -+ bt = q->blk_trace; -+ q->blk_trace = NULL; -+ ret = 0; -+ } -+ spin_unlock_irq(q->queue_lock); -+ -+ up(&bdev->bd_sem); -+ -+ if (bt) { -+ relay_close(bt->rchan); -+ kfree(bt); -+ } -+ -+ return ret; -+} -+ -+int blk_start_trace(struct block_device *bdev, char __user *arg) -+{ -+ request_queue_t *q = bdev_get_queue(bdev); -+ struct blk_user_trace_setup buts; -+ struct blk_trace *bt; -+ char b[BDEVNAME_SIZE]; -+ int ret = 0; -+ -+ if (!q) -+ return -ENXIO; -+ -+ if (copy_from_user(&buts, arg, sizeof(buts))) -+ return -EFAULT; -+ -+ if (!buts.buf_size || !buts.buf_nr) -+ return -EINVAL; -+ -+ strcpy(buts.name, bdevname(bdev, b)); -+ -+ if (copy_to_user(arg, &buts, sizeof(buts))) -+ return -EFAULT; -+ -+ down(&bdev->bd_sem); -+ ret = -EBUSY; -+ if (q->blk_trace) -+ goto err; -+ -+ ret = -ENOMEM; -+ bt = kmalloc(sizeof(*bt), GFP_KERNEL); -+ if (!bt) -+ goto err; -+ -+ atomic_set(&bt->sequence, 0); -+ -+ bt->rchan = relay_open(bdevname(bdev, b), NULL, buts.buf_size, -+ buts.buf_nr, NULL); -+ ret = -EIO; -+ if (!bt->rchan) -+ goto err; -+ -+ bt->act_mask = buts.act_mask; -+ if (!bt->act_mask) -+ bt->act_mask = (u16) -1; -+ -+ spin_lock_irq(q->queue_lock); -+ q->blk_trace = bt; -+ spin_unlock_irq(q->queue_lock); -+ ret = 0; -+err: -+ up(&bdev->bd_sem); -+ return ret; -+} -+ -+static void blk_trace_check_cpu_time(void *data) -+{ -+ unsigned long long a, b, *t; -+ struct timeval tv; -+ int cpu = get_cpu(); -+ -+ t = &per_cpu(blk_trace_cpu_offset, cpu); -+ -+ a = sched_clock(); -+ do_gettimeofday(&tv); -+ b = sched_clock(); -+ -+ *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; -+ *t -= (a + b) / 2; -+ put_cpu(); -+} -+ -+static int blk_trace_calibrate_offsets(void) -+{ -+ int cpus = num_online_cpus(); -+ unsigned long flags; -+ long long *time_offset; -+ -+ time_offset = kmalloc(cpus * sizeof(long long), GFP_KERNEL); -+ if (!time_offset) { -+ printk(KERN_ERR "blktrace: time offsets will be unreliable\n"); -+ return -ENOMEM; -+ } -+ -+ memset(time_offset, 0, cpus * sizeof(long long)); -+ -+ smp_call_function(blk_trace_check_cpu_time, time_offset, 1, 1); -+ local_irq_save(flags); -+ blk_trace_check_cpu_time(time_offset); -+ local_irq_restore(flags); -+ -+ kfree(time_offset); -+ return 0; -+} -+ -+static __init int blk_trace_init(void) -+{ -+ return blk_trace_calibrate_offsets(); -+} -+ -+module_init(blk_trace_init); -+ -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/elevator.c linux-2.6.13-rc6-mm2/drivers/block/elevator.c ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/elevator.c 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/drivers/block/elevator.c 2005-08-26 11:03:38.000000000 +0200 -@@ -34,6 +34,7 @@ - #include - #include - #include -+#include - - #include - -@@ -371,6 +372,9 @@ struct request *elv_next_request(request - int ret; - - while ((rq = __elv_next_request(q)) != NULL) { -+ -+ blk_add_trace_rq(q, rq, BLK_TA_ISSUE); -+ - /* - * just mark as started even if we don't start it, a request - * that has been delayed should not be passed by new incoming -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/ioctl.c linux-2.6.13-rc6-mm2/drivers/block/ioctl.c ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/ioctl.c 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/drivers/block/ioctl.c 2005-08-26 11:03:38.000000000 +0200 -@@ -4,6 +4,7 @@ - #include - #include - #include -+#include - #include - - static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) -@@ -188,6 +189,10 @@ static int blkdev_locked_ioctl(struct fi - return put_ulong(arg, bdev->bd_inode->i_size >> 9); - case BLKGETSIZE64: - return put_u64(arg, bdev->bd_inode->i_size); -+ case BLKSTARTTRACE: -+ return blk_start_trace(bdev, (char __user *) arg); -+ case BLKSTOPTRACE: -+ return blk_stop_trace(bdev); - } - return -ENOIOCTLCMD; - } -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/Kconfig linux-2.6.13-rc6-mm2/drivers/block/Kconfig ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/Kconfig 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/drivers/block/Kconfig 2005-08-29 08:00:42.000000000 +0200 -@@ -419,6 +419,14 @@ config LBD - your machine, or if you want to have a raid or loopback device - bigger than 2TB. Otherwise say N. - -+config BLK_DEV_IO_TRACE -+ bool "Support for tracing block io actions" -+ select RELAYFS_FS -+ help -+ Say Y here, if you want to be able to trace the block layer actions -+ on a given queue. -+ -+ - config CDROM_PKTCDVD - tristate "Packet writing on CD/DVD media" - depends on !UML -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/ll_rw_blk.c linux-2.6.13-rc6-mm2/drivers/block/ll_rw_blk.c ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/ll_rw_blk.c 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/drivers/block/ll_rw_blk.c 2005-08-26 11:03:38.000000000 +0200 -@@ -29,6 +29,7 @@ - #include - #include - #include -+#include - - /* - * for max sense size -@@ -1625,6 +1626,12 @@ void blk_cleanup_queue(request_queue_t * - if (q->queue_tags) - __blk_queue_free_tags(q); - -+ if (q->blk_trace) { -+ relay_close(q->blk_trace->rchan); -+ kfree(q->blk_trace); -+ q->blk_trace = NULL; -+ } -+ - blk_queue_ordered(q, QUEUE_ORDERED_NONE); - - kmem_cache_free(requestq_cachep, q); -@@ -1971,6 +1978,8 @@ rq_starved: - - rq_init(q, rq); - rq->rl = rl; -+ -+ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ); - out: - return rq; - } -@@ -1999,6 +2008,8 @@ static struct request *get_request_wait( - if (!rq) { - struct io_context *ioc; - -+ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ); -+ - __generic_unplug_device(q); - spin_unlock_irq(q->queue_lock); - io_schedule(); -@@ -2052,6 +2063,8 @@ EXPORT_SYMBOL(blk_get_request); - */ - void blk_requeue_request(request_queue_t *q, struct request *rq) - { -+ blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); -+ - if (blk_rq_tagged(rq)) - blk_queue_end_tag(q, rq); - -@@ -2665,6 +2678,8 @@ static int __make_request(request_queue_ - if (!q->back_merge_fn(q, req, bio)) - break; - -+ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); -+ - req->biotail->bi_next = bio; - req->biotail = bio; - req->nr_sectors = req->hard_nr_sectors += nr_sectors; -@@ -2680,6 +2695,8 @@ static int __make_request(request_queue_ - if (!q->front_merge_fn(q, req, bio)) - break; - -+ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); -+ - bio->bi_next = req->bio; - req->bio = bio; - -@@ -2705,6 +2722,8 @@ static int __make_request(request_queue_ - } - - get_rq: -+ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); -+ - /* - * Grab a free request. This is might sleep but can not fail. - * Returns with the queue unlocked. -@@ -2981,6 +3000,10 @@ end_io: - blk_partition_remap(bio); - - ret = q->make_request_fn(q, bio); -+ -+ if (ret) -+ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); -+ - } while (ret); - } - -@@ -3099,6 +3122,8 @@ static int __end_that_request_first(stru - int total_bytes, bio_nbytes, error, next_idx = 0; - struct bio *bio; - -+ blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE); -+ - /* - * extend uptodate bool to allow < 0 value to be direct io error - */ -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/Makefile linux-2.6.13-rc6-mm2/drivers/block/Makefile ---- /opt/kernel/linux-2.6.13-rc6-mm2/drivers/block/Makefile 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/drivers/block/Makefile 2005-08-26 11:03:38.000000000 +0200 -@@ -45,3 +45,5 @@ obj-$(CONFIG_VIODASD) += viodasd.o - obj-$(CONFIG_BLK_DEV_SX8) += sx8.o - obj-$(CONFIG_BLK_DEV_UB) += ub.o - -+obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o -+ -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/blkdev.h linux-2.6.13-rc6-mm2/include/linux/blkdev.h ---- /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/blkdev.h 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/include/linux/blkdev.h 2005-08-26 11:03:38.000000000 +0200 -@@ -22,6 +22,7 @@ typedef struct request_queue request_que - struct elevator_queue; - typedef struct elevator_queue elevator_t; - struct request_pm_state; -+struct blk_trace; - - #define BLKDEV_MIN_RQ 4 - #define BLKDEV_MAX_RQ 128 /* Default maximum */ -@@ -412,6 +413,8 @@ struct request_queue - */ - struct request *flush_rq; - unsigned char ordered; -+ -+ struct blk_trace *blk_trace; - }; - - enum { -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/blktrace.h linux-2.6.13-rc6-mm2/include/linux/blktrace.h ---- /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/blktrace.h 1970-01-01 01:00:00.000000000 +0100 -+++ linux-2.6.13-rc6-mm2/include/linux/blktrace.h 2005-08-30 09:57:59.000000000 +0200 -@@ -0,0 +1,145 @@ -+#ifndef BLKTRACE_H -+#define BLKTRACE_H -+ -+#include -+#include -+#include -+ -+/* -+ * Trace categories -+ */ -+enum { -+ BLK_TC_READ = 1 << 0, /* reads */ -+ BLK_TC_WRITE = 1 << 1, /* writes */ -+ BLK_TC_BARRIER = 1 << 2, /* barrier */ -+ BLK_TC_SYNC = 1 << 3, /* barrier */ -+ BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ -+ BLK_TC_REQUEUE = 1 << 5, /* requeueing */ -+ BLK_TC_ISSUE = 1 << 6, /* issue */ -+ BLK_TC_COMPLETE = 1 << 7, /* completions */ -+ BLK_TC_FS = 1 << 8, /* fs requests */ -+ BLK_TC_PC = 1 << 9, /* pc requests */ -+ -+ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ -+}; -+ -+#define BLK_TC_SHIFT (16) -+#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) -+ -+/* -+ * Basic trace actions -+ */ -+enum { -+ __BLK_TA_QUEUE = 1, /* queued */ -+ __BLK_TA_BACKMERGE, /* back merged to existing rq */ -+ __BLK_TA_FRONTMERGE, /* front merge to existing rq */ -+ __BLK_TA_GETRQ, /* allocated new request */ -+ __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ -+ __BLK_TA_REQUEUE, /* request requeued */ -+ __BLK_TA_ISSUE, /* sent to driver */ -+ __BLK_TA_COMPLETE, /* completed by driver */ -+}; -+ -+/* -+ * Trace actions in full. Additionally, read or write is masked -+ */ -+#define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) -+#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) -+#define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) -+#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) -+ -+#define BLK_IO_TRACE_MAGIC 0x65617400 -+#define BLK_IO_TRACE_VERSION 0x02 -+ -+/* -+ * The trace itself -+ */ -+struct blk_io_trace { -+ u32 magic; /* MAGIC << 8 | version */ -+ u32 sequence; /* event number */ -+ u64 time; /* in microseconds */ -+ u64 sector; /* disk offset */ -+ u32 bytes; /* transfer length */ -+ u32 action; /* what happened */ -+ u32 pid; /* who did it */ -+ u16 error; /* completion error */ -+ u16 pdu_len; /* length of data after this trace */ -+}; -+ -+struct blk_trace { -+ struct rchan *rchan; -+ atomic_t sequence; -+ u16 act_mask; -+}; -+ -+/* -+ * User setup structure passed with BLKSTARTTRACE -+ */ -+struct blk_user_trace_setup { -+ char name[BDEVNAME_SIZE]; /* output */ -+ u16 act_mask; /* input */ -+ u32 buf_size; /* input */ -+ u32 buf_nr; /* input */ -+}; -+ -+#if defined(CONFIG_BLK_DEV_IO_TRACE) -+extern int blk_start_trace(struct block_device *, char __user *); -+extern int blk_stop_trace(struct block_device *); -+extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, char *); -+ -+static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, -+ u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ int rw = rq->flags & 0x07; -+ -+ if (likely(!bt)) -+ return; -+ -+ if (blk_pc_request(rq)) { -+ what |= BLK_TC_ACT(BLK_TC_PC); -+ __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); -+ } else { -+ what |= BLK_TC_ACT(BLK_TC_FS); -+ __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); -+ } -+} -+ -+static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, -+ u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ -+ if (likely(!bt)) -+ return; -+ -+ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); -+} -+ -+static inline void blk_add_trace_generic(struct request_queue *q, -+ struct bio *bio, int rw, u32 what) -+{ -+ struct blk_trace *bt = q->blk_trace; -+ -+ if (likely(!bt)) -+ return; -+ -+ if (bio) -+ blk_add_trace_bio(q, bio, what); -+ else -+ __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); -+} -+ -+#else /* !CONFIG_BLK_DEV_IO_TRACE */ -+#define blk_start_trace(bdev, arg) (-EINVAL) -+#define blk_stop_trace(bdev) (-EINVAL) -+#define blk_add_trace_rq(q, rq, what) do { } while (0) -+#define blk_add_trace_bio(q, rq, what) do { } while (0) -+#define blk_add_trace_generic(q, rq, rw, what) do { } while (0) -+#endif /* CONFIG_BLK_DEV_IO_TRACE */ -+ -+#endif -diff -urpN -X linux-2.6.13-rc6-mm2/Documentation/dontdiff /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/fs.h linux-2.6.13-rc6-mm2/include/linux/fs.h ---- /opt/kernel/linux-2.6.13-rc6-mm2/include/linux/fs.h 2005-08-30 20:55:03.000000000 +0200 -+++ linux-2.6.13-rc6-mm2/include/linux/fs.h 2005-08-26 11:03:38.000000000 +0200 -@@ -196,6 +196,8 @@ extern int dir_notify_enable; - #define BLKBSZGET _IOR(0x12,112,size_t) - #define BLKBSZSET _IOW(0x12,113,size_t) - #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ -+#define BLKSTARTTRACE _IOWR(0x12,115,struct blk_user_trace_setup) -+#define BLKSTOPTRACE _IO(0x12,116) - - #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ - #define FIBMAP _IO(0x00,1) /* bmap access */ diff --git a/kernel/blk-trace-2.6.13-mm1-B0 b/kernel/blk-trace-2.6.13-mm1-B0 new file mode 100644 index 0000000..4d00ba7 --- /dev/null +++ b/kernel/blk-trace-2.6.13-mm1-B0 @@ -0,0 +1,526 @@ +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/blktrace.c linux-2.6.13-mm1/drivers/block/blktrace.c +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/blktrace.c 1970-01-01 01:00:00.000000000 +0100 ++++ linux-2.6.13-mm1/drivers/block/blktrace.c 2005-09-01 14:54:51.000000000 +0200 +@@ -0,0 +1,173 @@ ++#include ++#include ++#include ++#include ++#include ++#include ++#include ++ ++static DEFINE_PER_CPU(unsigned long long, blk_trace_cpu_offset) = { 0, }; ++ ++static inline unsigned long long blk_trace_cpu_time(void) ++{ ++ unsigned long long offset; ++ ++ offset = sched_clock() - per_cpu(blk_trace_cpu_offset, get_cpu()); ++ put_cpu(); ++ return offset; ++} ++ ++void __blk_add_trace(struct blk_trace *bt, sector_t sector, int bytes, ++ int rw, u32 what, int error, int pdu_len, char *pdu_data) ++{ ++ struct blk_io_trace t; ++ unsigned long flags; ++ ++ if (rw & (1 << BIO_RW_BARRIER)) ++ what |= BLK_TC_ACT(BLK_TC_BARRIER); ++ if (rw & (1 << BIO_RW_SYNC)) ++ what |= BLK_TC_ACT(BLK_TC_SYNC); ++ ++ if (rw & WRITE) ++ what |= BLK_TC_ACT(BLK_TC_WRITE); ++ else ++ what |= BLK_TC_ACT(BLK_TC_READ); ++ ++ if (((bt->act_mask << BLK_TC_SHIFT) & what) == 0) ++ return; ++ ++ t.magic = BLK_IO_TRACE_MAGIC | BLK_IO_TRACE_VERSION; ++ t.sequence = atomic_add_return(1, &bt->sequence); ++ t.time = blk_trace_cpu_time(); ++ t.sector = sector; ++ t.bytes = bytes; ++ t.action = what; ++ t.pid = current->pid; ++ t.error = error; ++ t.pdu_len = pdu_len; ++ ++ local_irq_save(flags); ++ __relay_write(bt->rchan, &t, sizeof(t)); ++ if (pdu_len) ++ __relay_write(bt->rchan, pdu_data, pdu_len); ++ local_irq_restore(flags); ++} ++ ++int blk_stop_trace(struct block_device *bdev) ++{ ++ request_queue_t *q = bdev_get_queue(bdev); ++ struct blk_trace *bt = NULL; ++ int ret = -EINVAL; ++ ++ if (!q) ++ return -ENXIO; ++ ++ down(&bdev->bd_sem); ++ ++ spin_lock_irq(q->queue_lock); ++ if (q->blk_trace) { ++ bt = q->blk_trace; ++ q->blk_trace = NULL; ++ ret = 0; ++ } ++ spin_unlock_irq(q->queue_lock); ++ ++ up(&bdev->bd_sem); ++ ++ if (bt) { ++ relay_close(bt->rchan); ++ kfree(bt); ++ } ++ ++ return ret; ++} ++ ++int blk_start_trace(struct block_device *bdev, char __user *arg) ++{ ++ request_queue_t *q = bdev_get_queue(bdev); ++ struct blk_user_trace_setup buts; ++ struct blk_trace *bt; ++ char b[BDEVNAME_SIZE]; ++ int ret = 0; ++ ++ if (!q) ++ return -ENXIO; ++ ++ if (copy_from_user(&buts, arg, sizeof(buts))) ++ return -EFAULT; ++ ++ if (!buts.buf_size || !buts.buf_nr) ++ return -EINVAL; ++ ++ strcpy(buts.name, bdevname(bdev, b)); ++ ++ if (copy_to_user(arg, &buts, sizeof(buts))) ++ return -EFAULT; ++ ++ down(&bdev->bd_sem); ++ ret = -EBUSY; ++ if (q->blk_trace) ++ goto err; ++ ++ ret = -ENOMEM; ++ bt = kmalloc(sizeof(*bt), GFP_KERNEL); ++ if (!bt) ++ goto err; ++ ++ atomic_set(&bt->sequence, 0); ++ ++ bt->rchan = relay_open(bdevname(bdev, b), NULL, buts.buf_size, ++ buts.buf_nr, NULL); ++ ret = -EIO; ++ if (!bt->rchan) ++ goto err; ++ ++ bt->act_mask = buts.act_mask; ++ if (!bt->act_mask) ++ bt->act_mask = (u16) -1; ++ ++ spin_lock_irq(q->queue_lock); ++ q->blk_trace = bt; ++ spin_unlock_irq(q->queue_lock); ++ ret = 0; ++err: ++ up(&bdev->bd_sem); ++ return ret; ++} ++ ++static void blk_trace_check_cpu_time(void *data) ++{ ++ unsigned long long a, b, *t; ++ struct timeval tv; ++ int cpu = get_cpu(); ++ ++ t = &per_cpu(blk_trace_cpu_offset, cpu); ++ ++ a = sched_clock(); ++ do_gettimeofday(&tv); ++ b = sched_clock(); ++ ++ *t = tv.tv_sec * 1000000000 + tv.tv_usec * 1000; ++ *t -= (a + b) / 2; ++ put_cpu(); ++} ++ ++static int 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); ++ ++ return 0; ++} ++ ++static __init int blk_trace_init(void) ++{ ++ return blk_trace_calibrate_offsets(); ++} ++ ++module_init(blk_trace_init); ++ +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/elevator.c linux-2.6.13-mm1/drivers/block/elevator.c +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/elevator.c 2005-09-01 13:07:30.000000000 +0200 ++++ linux-2.6.13-mm1/drivers/block/elevator.c 2005-09-01 13:08:42.000000000 +0200 +@@ -34,6 +34,7 @@ + #include + #include + #include ++#include + + #include + +@@ -371,6 +372,9 @@ struct request *elv_next_request(request + int ret; + + while ((rq = __elv_next_request(q)) != NULL) { ++ ++ blk_add_trace_rq(q, rq, BLK_TA_ISSUE); ++ + /* + * just mark as started even if we don't start it, a request + * that has been delayed should not be passed by new incoming +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/ioctl.c linux-2.6.13-mm1/drivers/block/ioctl.c +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/ioctl.c 2005-09-01 13:07:30.000000000 +0200 ++++ linux-2.6.13-mm1/drivers/block/ioctl.c 2005-09-01 13:08:42.000000000 +0200 +@@ -4,6 +4,7 @@ + #include + #include + #include ++#include + #include + + static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) +@@ -188,6 +189,10 @@ static int blkdev_locked_ioctl(struct fi + return put_ulong(arg, bdev->bd_inode->i_size >> 9); + case BLKGETSIZE64: + return put_u64(arg, bdev->bd_inode->i_size); ++ case BLKSTARTTRACE: ++ return blk_start_trace(bdev, (char __user *) arg); ++ case BLKSTOPTRACE: ++ return blk_stop_trace(bdev); + } + return -ENOIOCTLCMD; + } +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/Kconfig linux-2.6.13-mm1/drivers/block/Kconfig +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/Kconfig 2005-09-01 13:07:30.000000000 +0200 ++++ linux-2.6.13-mm1/drivers/block/Kconfig 2005-09-01 13:08:42.000000000 +0200 +@@ -419,6 +419,14 @@ config LBD + your machine, or if you want to have a raid or loopback device + bigger than 2TB. Otherwise say N. + ++config BLK_DEV_IO_TRACE ++ bool "Support for tracing block io actions" ++ select RELAYFS_FS ++ help ++ Say Y here, if you want to be able to trace the block layer actions ++ on a given queue. ++ ++ + config CDROM_PKTCDVD + tristate "Packet writing on CD/DVD media" + depends on !UML +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/ll_rw_blk.c linux-2.6.13-mm1/drivers/block/ll_rw_blk.c +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/ll_rw_blk.c 2005-09-01 13:07:30.000000000 +0200 ++++ linux-2.6.13-mm1/drivers/block/ll_rw_blk.c 2005-09-01 13:08:42.000000000 +0200 +@@ -29,6 +29,7 @@ + #include + #include + #include ++#include + + /* + * for max sense size +@@ -1625,6 +1626,12 @@ void blk_cleanup_queue(request_queue_t * + if (q->queue_tags) + __blk_queue_free_tags(q); + ++ if (q->blk_trace) { ++ relay_close(q->blk_trace->rchan); ++ kfree(q->blk_trace); ++ q->blk_trace = NULL; ++ } ++ + blk_queue_ordered(q, QUEUE_ORDERED_NONE); + + kmem_cache_free(requestq_cachep, q); +@@ -1971,6 +1978,8 @@ rq_starved: + + rq_init(q, rq); + rq->rl = rl; ++ ++ blk_add_trace_generic(q, bio, rw, BLK_TA_GETRQ); + out: + return rq; + } +@@ -1999,6 +2008,8 @@ static struct request *get_request_wait( + if (!rq) { + struct io_context *ioc; + ++ blk_add_trace_generic(q, bio, rw, BLK_TA_SLEEPRQ); ++ + __generic_unplug_device(q); + spin_unlock_irq(q->queue_lock); + io_schedule(); +@@ -2052,6 +2063,8 @@ EXPORT_SYMBOL(blk_get_request); + */ + void blk_requeue_request(request_queue_t *q, struct request *rq) + { ++ blk_add_trace_rq(q, rq, BLK_TA_REQUEUE); ++ + if (blk_rq_tagged(rq)) + blk_queue_end_tag(q, rq); + +@@ -2665,6 +2678,8 @@ static int __make_request(request_queue_ + if (!q->back_merge_fn(q, req, bio)) + break; + ++ blk_add_trace_bio(q, bio, BLK_TA_BACKMERGE); ++ + req->biotail->bi_next = bio; + req->biotail = bio; + req->nr_sectors = req->hard_nr_sectors += nr_sectors; +@@ -2680,6 +2695,8 @@ static int __make_request(request_queue_ + if (!q->front_merge_fn(q, req, bio)) + break; + ++ blk_add_trace_bio(q, bio, BLK_TA_FRONTMERGE); ++ + bio->bi_next = req->bio; + req->bio = bio; + +@@ -2705,6 +2722,8 @@ static int __make_request(request_queue_ + } + + get_rq: ++ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); ++ + /* + * Grab a free request. This is might sleep but can not fail. + * Returns with the queue unlocked. +@@ -2981,6 +3000,10 @@ end_io: + blk_partition_remap(bio); + + ret = q->make_request_fn(q, bio); ++ ++ if (ret) ++ blk_add_trace_bio(q, bio, BLK_TA_QUEUE); ++ + } while (ret); + } + +@@ -3099,6 +3122,8 @@ static int __end_that_request_first(stru + int total_bytes, bio_nbytes, error, next_idx = 0; + struct bio *bio; + ++ blk_add_trace_rq(req->q, req, BLK_TA_COMPLETE); ++ + /* + * extend uptodate bool to allow < 0 value to be direct io error + */ +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/drivers/block/Makefile linux-2.6.13-mm1/drivers/block/Makefile +--- /opt/kernel/linux-2.6.13-mm1/drivers/block/Makefile 2005-09-01 13:07:30.000000000 +0200 ++++ linux-2.6.13-mm1/drivers/block/Makefile 2005-09-01 13:08:42.000000000 +0200 +@@ -45,3 +45,5 @@ obj-$(CONFIG_VIODASD) += viodasd.o + obj-$(CONFIG_BLK_DEV_SX8) += sx8.o + obj-$(CONFIG_BLK_DEV_UB) += ub.o + ++obj-$(CONFIG_BLK_DEV_IO_TRACE) += blktrace.o ++ +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/include/linux/blkdev.h linux-2.6.13-mm1/include/linux/blkdev.h +--- /opt/kernel/linux-2.6.13-mm1/include/linux/blkdev.h 2005-09-01 13:07:53.000000000 +0200 ++++ linux-2.6.13-mm1/include/linux/blkdev.h 2005-09-01 13:08:42.000000000 +0200 +@@ -22,6 +22,7 @@ typedef struct request_queue request_que + struct elevator_queue; + typedef struct elevator_queue elevator_t; + struct request_pm_state; ++struct blk_trace; + + #define BLKDEV_MIN_RQ 4 + #define BLKDEV_MAX_RQ 128 /* Default maximum */ +@@ -412,6 +413,8 @@ struct request_queue + */ + struct request *flush_rq; + unsigned char ordered; ++ ++ struct blk_trace *blk_trace; + }; + + enum { +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/include/linux/blktrace.h linux-2.6.13-mm1/include/linux/blktrace.h +--- /opt/kernel/linux-2.6.13-mm1/include/linux/blktrace.h 1970-01-01 01:00:00.000000000 +0100 ++++ linux-2.6.13-mm1/include/linux/blktrace.h 2005-09-01 13:08:42.000000000 +0200 +@@ -0,0 +1,145 @@ ++#ifndef BLKTRACE_H ++#define BLKTRACE_H ++ ++#include ++#include ++#include ++ ++/* ++ * Trace categories ++ */ ++enum { ++ BLK_TC_READ = 1 << 0, /* reads */ ++ BLK_TC_WRITE = 1 << 1, /* writes */ ++ BLK_TC_BARRIER = 1 << 2, /* barrier */ ++ BLK_TC_SYNC = 1 << 3, /* barrier */ ++ BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ ++ BLK_TC_REQUEUE = 1 << 5, /* requeueing */ ++ BLK_TC_ISSUE = 1 << 6, /* issue */ ++ BLK_TC_COMPLETE = 1 << 7, /* completions */ ++ BLK_TC_FS = 1 << 8, /* fs requests */ ++ BLK_TC_PC = 1 << 9, /* pc requests */ ++ ++ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ ++}; ++ ++#define BLK_TC_SHIFT (16) ++#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) ++ ++/* ++ * Basic trace actions ++ */ ++enum { ++ __BLK_TA_QUEUE = 1, /* queued */ ++ __BLK_TA_BACKMERGE, /* back merged to existing rq */ ++ __BLK_TA_FRONTMERGE, /* front merge to existing rq */ ++ __BLK_TA_GETRQ, /* allocated new request */ ++ __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ ++ __BLK_TA_REQUEUE, /* request requeued */ ++ __BLK_TA_ISSUE, /* sent to driver */ ++ __BLK_TA_COMPLETE, /* completed by driver */ ++}; ++ ++/* ++ * Trace actions in full. Additionally, read or write is masked ++ */ ++#define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) ++#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) ++#define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) ++#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) ++ ++#define BLK_IO_TRACE_MAGIC 0x65617400 ++#define BLK_IO_TRACE_VERSION 0x02 ++ ++/* ++ * The trace itself ++ */ ++struct blk_io_trace { ++ u32 magic; /* MAGIC << 8 | version */ ++ u32 sequence; /* event number */ ++ u64 time; /* in microseconds */ ++ u64 sector; /* disk offset */ ++ u32 bytes; /* transfer length */ ++ u32 action; /* what happened */ ++ u32 pid; /* who did it */ ++ u16 error; /* completion error */ ++ u16 pdu_len; /* length of data after this trace */ ++}; ++ ++struct blk_trace { ++ struct rchan *rchan; ++ atomic_t sequence; ++ u16 act_mask; ++}; ++ ++/* ++ * User setup structure passed with BLKSTARTTRACE ++ */ ++struct blk_user_trace_setup { ++ char name[BDEVNAME_SIZE]; /* output */ ++ u16 act_mask; /* input */ ++ u32 buf_size; /* input */ ++ u32 buf_nr; /* input */ ++}; ++ ++#if defined(CONFIG_BLK_DEV_IO_TRACE) ++extern int blk_start_trace(struct block_device *, char __user *); ++extern int blk_stop_trace(struct block_device *); ++extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, char *); ++ ++static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, ++ u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ int rw = rq->flags & 0x07; ++ ++ if (likely(!bt)) ++ return; ++ ++ if (blk_pc_request(rq)) { ++ what |= BLK_TC_ACT(BLK_TC_PC); ++ __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); ++ } else { ++ what |= BLK_TC_ACT(BLK_TC_FS); ++ __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); ++ } ++} ++ ++static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, ++ u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ ++ if (likely(!bt)) ++ return; ++ ++ __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); ++} ++ ++static inline void blk_add_trace_generic(struct request_queue *q, ++ struct bio *bio, int rw, u32 what) ++{ ++ struct blk_trace *bt = q->blk_trace; ++ ++ if (likely(!bt)) ++ return; ++ ++ if (bio) ++ blk_add_trace_bio(q, bio, what); ++ else ++ __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); ++} ++ ++#else /* !CONFIG_BLK_DEV_IO_TRACE */ ++#define blk_start_trace(bdev, arg) (-EINVAL) ++#define blk_stop_trace(bdev) (-EINVAL) ++#define blk_add_trace_rq(q, rq, what) do { } while (0) ++#define blk_add_trace_bio(q, rq, what) do { } while (0) ++#define blk_add_trace_generic(q, rq, rw, what) do { } while (0) ++#endif /* CONFIG_BLK_DEV_IO_TRACE */ ++ ++#endif +diff -urpN -X linux-2.6.13-mm1/Documentation/dontdiff /opt/kernel/linux-2.6.13-mm1/include/linux/fs.h linux-2.6.13-mm1/include/linux/fs.h +--- /opt/kernel/linux-2.6.13-mm1/include/linux/fs.h 2005-09-01 13:07:53.000000000 +0200 ++++ linux-2.6.13-mm1/include/linux/fs.h 2005-09-01 13:08:42.000000000 +0200 +@@ -196,6 +196,8 @@ extern int dir_notify_enable; + #define BLKBSZGET _IOR(0x12,112,size_t) + #define BLKBSZSET _IOW(0x12,113,size_t) + #define BLKGETSIZE64 _IOR(0x12,114,size_t) /* return device size in bytes (u64 *arg) */ ++#define BLKSTARTTRACE _IOWR(0x12,115,struct blk_user_trace_setup) ++#define BLKSTOPTRACE _IO(0x12,116) + + #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ + #define FIBMAP _IO(0x00,1) /* bmap access */