From b86ff981a8252d83d6a7719ae09f3a05307e3592 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 23 Mar 2006 19:56:55 +0100 Subject: [PATCH] relay: migrate from relayfs to a generic relay API Original patch from Paul Mundt, sysfs parts removed by me since they were broken. Signed-off-by: Jens Axboe --- include/linux/relay.h | 281 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 281 insertions(+) create mode 100644 include/linux/relay.h (limited to 'include') diff --git a/include/linux/relay.h b/include/linux/relay.h new file mode 100644 index 0000000..4bcc153 --- /dev/null +++ b/include/linux/relay.h @@ -0,0 +1,281 @@ +/* + * linux/include/linux/relay.h + * + * Copyright (C) 2002, 2003 - Tom Zanussi (zanussi@us.ibm.com), IBM Corp + * Copyright (C) 1999, 2000, 2001, 2002 - Karim Yaghmour (karim@opersys.com) + * + * CONFIG_RELAY definitions and declarations + */ + +#ifndef _LINUX_RELAY_H +#define _LINUX_RELAY_H + +#include +#include +#include +#include +#include +#include +#include +#include + +/* Needs a _much_ better name... */ +#define FIX_SIZE(x) ((((x) - 1) & PAGE_MASK) + PAGE_SIZE) + +/* + * Tracks changes to rchan/rchan_buf structs + */ +#define RELAYFS_CHANNEL_VERSION 6 + +/* + * Per-cpu relay channel buffer + */ +struct rchan_buf +{ + void *start; /* start of channel buffer */ + void *data; /* start of current sub-buffer */ + size_t offset; /* current offset into sub-buffer */ + size_t subbufs_produced; /* count of sub-buffers produced */ + size_t subbufs_consumed; /* count of sub-buffers consumed */ + struct rchan *chan; /* associated channel */ + wait_queue_head_t read_wait; /* reader wait queue */ + struct work_struct wake_readers; /* reader wake-up work struct */ + struct dentry *dentry; /* channel file dentry */ + struct kref kref; /* channel buffer refcount */ + struct page **page_array; /* array of current buffer pages */ + unsigned int page_count; /* number of current buffer pages */ + unsigned int finalized; /* buffer has been finalized */ + size_t *padding; /* padding counts per sub-buffer */ + size_t prev_padding; /* temporary variable */ + size_t bytes_consumed; /* bytes consumed in cur read subbuf */ + unsigned int cpu; /* this buf's cpu */ +} ____cacheline_aligned; + +/* + * Relay channel data structure + */ +struct rchan +{ + u32 version; /* the version of this struct */ + size_t subbuf_size; /* sub-buffer size */ + size_t n_subbufs; /* number of sub-buffers per buffer */ + size_t alloc_size; /* total buffer size allocated */ + struct rchan_callbacks *cb; /* client callbacks */ + struct kref kref; /* channel refcount */ + void *private_data; /* for user-defined data */ + size_t last_toobig; /* tried to log event > subbuf size */ + struct rchan_buf *buf[NR_CPUS]; /* per-cpu channel buffers */ +}; + +/* + * Relay channel client callbacks + */ +struct rchan_callbacks +{ + /* + * subbuf_start - called on buffer-switch to a new sub-buffer + * @buf: the channel buffer containing the new sub-buffer + * @subbuf: the start of the new sub-buffer + * @prev_subbuf: the start of the previous sub-buffer + * @prev_padding: unused space at the end of previous sub-buffer + * + * The client should return 1 to continue logging, 0 to stop + * logging. + * + * NOTE: subbuf_start will also be invoked when the buffer is + * created, so that the first sub-buffer can be initialized + * if necessary. In this case, prev_subbuf will be NULL. + * + * NOTE: the client can reserve bytes at the beginning of the new + * sub-buffer by calling subbuf_start_reserve() in this callback. + */ + int (*subbuf_start) (struct rchan_buf *buf, + void *subbuf, + void *prev_subbuf, + size_t prev_padding); + + /* + * buf_mapped - relay buffer mmap notification + * @buf: the channel buffer + * @filp: relay file pointer + * + * Called when a relay file is successfully mmapped + */ + void (*buf_mapped)(struct rchan_buf *buf, + struct file *filp); + + /* + * buf_unmapped - relay buffer unmap notification + * @buf: the channel buffer + * @filp: relay file pointer + * + * Called when a relay file is successfully unmapped + */ + void (*buf_unmapped)(struct rchan_buf *buf, + struct file *filp); + /* + * create_buf_file - create file to represent a relay channel buffer + * @filename: the name of the file to create + * @parent: the parent of the file to create + * @mode: the mode of the file to create + * @buf: the channel buffer + * @is_global: outparam - set non-zero if the buffer should be global + * + * Called during relay_open(), once for each per-cpu buffer, + * to allow the client to create a file to be used to + * represent the corresponding channel buffer. If the file is + * created outside of relay, the parent must also exist in + * that filesystem. + * + * The callback should return the dentry of the file created + * to represent the relay buffer. + * + * Setting the is_global outparam to a non-zero value will + * cause relay_open() to create a single global buffer rather + * than the default set of per-cpu buffers. + * + * See Documentation/filesystems/relayfs.txt for more info. + */ + struct dentry *(*create_buf_file)(const char *filename, + struct dentry *parent, + int mode, + struct rchan_buf *buf, + int *is_global); + + /* + * remove_buf_file - remove file representing a relay channel buffer + * @dentry: the dentry of the file to remove + * + * Called during relay_close(), once for each per-cpu buffer, + * to allow the client to remove a file used to represent a + * channel buffer. + * + * The callback should return 0 if successful, negative if not. + */ + int (*remove_buf_file)(struct dentry *dentry); +}; + +/* + * CONFIG_RELAY kernel API, kernel/relay.c + */ + +struct rchan *relay_open(const char *base_filename, + struct dentry *parent, + size_t subbuf_size, + size_t n_subbufs, + struct rchan_callbacks *cb); +extern void relay_close(struct rchan *chan); +extern void relay_flush(struct rchan *chan); +extern void relay_subbufs_consumed(struct rchan *chan, + unsigned int cpu, + size_t consumed); +extern void relay_reset(struct rchan *chan); +extern int relay_buf_full(struct rchan_buf *buf); + +extern size_t relay_switch_subbuf(struct rchan_buf *buf, + size_t length); + +/** + * relay_write - write data into the channel + * @chan: relay channel + * @data: data to be written + * @length: number of bytes to write + * + * Writes data into the current cpu's channel buffer. + * + * Protects the buffer by disabling interrupts. Use this + * if you might be logging from interrupt context. Try + * __relay_write() if you know you won't be logging from + * interrupt context. + */ +static inline void relay_write(struct rchan *chan, + const void *data, + size_t length) +{ + unsigned long flags; + struct rchan_buf *buf; + + local_irq_save(flags); + buf = chan->buf[smp_processor_id()]; + if (unlikely(buf->offset + length > chan->subbuf_size)) + length = relay_switch_subbuf(buf, length); + memcpy(buf->data + buf->offset, data, length); + buf->offset += length; + local_irq_restore(flags); +} + +/** + * __relay_write - write data into the channel + * @chan: relay channel + * @data: data to be written + * @length: number of bytes to write + * + * Writes data into the current cpu's channel buffer. + * + * Protects the buffer by disabling preemption. Use + * relay_write() if you might be logging from interrupt + * context. + */ +static inline void __relay_write(struct rchan *chan, + const void *data, + size_t length) +{ + struct rchan_buf *buf; + + buf = chan->buf[get_cpu()]; + if (unlikely(buf->offset + length > buf->chan->subbuf_size)) + length = relay_switch_subbuf(buf, length); + memcpy(buf->data + buf->offset, data, length); + buf->offset += length; + put_cpu(); +} + +/** + * relay_reserve - reserve slot in channel buffer + * @chan: relay channel + * @length: number of bytes to reserve + * + * Returns pointer to reserved slot, NULL if full. + * + * Reserves a slot in the current cpu's channel buffer. + * Does not protect the buffer at all - caller must provide + * appropriate synchronization. + */ +static inline void *relay_reserve(struct rchan *chan, size_t length) +{ + void *reserved; + struct rchan_buf *buf = chan->buf[smp_processor_id()]; + + if (unlikely(buf->offset + length > buf->chan->subbuf_size)) { + length = relay_switch_subbuf(buf, length); + if (!length) + return NULL; + } + reserved = buf->data + buf->offset; + buf->offset += length; + + return reserved; +} + +/** + * subbuf_start_reserve - reserve bytes at the start of a sub-buffer + * @buf: relay channel buffer + * @length: number of bytes to reserve + * + * Helper function used to reserve bytes at the beginning of + * a sub-buffer in the subbuf_start() callback. + */ +static inline void subbuf_start_reserve(struct rchan_buf *buf, + size_t length) +{ + BUG_ON(length >= buf->chan->subbuf_size - 1); + buf->offset = length; +} + +/* + * exported relay file operations, kernel/relay.c + */ +extern struct file_operations relay_file_operations; + +#endif /* _LINUX_RELAY_H */ + -- cgit v1.1 From 2056a782f8e7e65fd4bfd027506b4ce1c5e9ccd4 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 23 Mar 2006 20:00:26 +0100 Subject: [PATCH] Block queue IO tracing support (blktrace) as of 2006-03-23 Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 3 + include/linux/blktrace_api.h | 277 +++++++++++++++++++++++++++++++++++++++++++ include/linux/compat_ioctl.h | 4 + include/linux/fs.h | 4 + include/linux/sched.h | 1 + 5 files changed, 289 insertions(+) create mode 100644 include/linux/blktrace_api.h (limited to 'include') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 56bb6a4..c179966 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -22,6 +22,7 @@ typedef struct request_queue request_queue_t; 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 */ @@ -416,6 +417,8 @@ struct request_queue unsigned int sg_reserved_size; int node; + struct blk_trace *blk_trace; + /* * reserved for flush operations */ diff --git a/include/linux/blktrace_api.h b/include/linux/blktrace_api.h new file mode 100644 index 0000000..b34d3e7 --- /dev/null +++ b/include/linux/blktrace_api.h @@ -0,0 +1,277 @@ +#ifndef BLKTRACE_H +#define BLKTRACE_H + +#include +#include +#include + +/* + * Trace categories + */ +enum blktrace_cat { + 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_NOTIFY = 1 << 10, /* special message */ + + 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 blktrace_act { + __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 */ + __BLK_TA_PLUG, /* queue was plugged */ + __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ + __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ + __BLK_TA_INSERT, /* insert request */ + __BLK_TA_SPLIT, /* bio was split */ + __BLK_TA_BOUNCE, /* bio was bounced */ + __BLK_TA_REMAP, /* bio was remapped */ +}; + +/* + * 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_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) +#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) +#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) +#define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) +#define BLK_TA_SPLIT (__BLK_TA_SPLIT) +#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) +#define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) + +#define BLK_IO_TRACE_MAGIC 0x65617400 +#define BLK_IO_TRACE_VERSION 0x07 + +/* + * 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 */ + u32 device; /* device number */ + u32 cpu; /* on what cpu did it happen */ + u16 error; /* completion error */ + u16 pdu_len; /* length of data after this trace */ +}; + +/* + * The remap event + */ +struct blk_io_trace_remap { + u32 device; + u32 __pad; + u64 sector; +}; + +enum { + Blktrace_setup = 1, + Blktrace_running, + Blktrace_stopped, +}; + +struct blk_trace { + int trace_state; + struct rchan *rchan; + unsigned long *sequence; + u16 act_mask; + u64 start_lba; + u64 end_lba; + u32 pid; + u32 dev; + struct dentry *dir; + struct dentry *dropped_file; + atomic_t dropped; +}; + +/* + * User setup structure passed with BLKTRACESTART + */ +struct blk_user_trace_setup { + char name[BDEVNAME_SIZE]; /* output */ + u16 act_mask; /* input */ + u32 buf_size; /* input */ + u32 buf_nr; /* input */ + u64 start_lba; + u64 end_lba; + u32 pid; +}; + +#if defined(CONFIG_BLK_DEV_IO_TRACE) +extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); +extern void blk_trace_shutdown(request_queue_t *); +extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); + +/** + * blk_add_trace_rq - Add a trace for a request oriented action + * @q: queue the io is for + * @rq: the source request + * @what: the action + * + * Description: + * Records an action against a request. Will log the bio offset + size. + * + **/ +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); + } +} + +/** + * blk_add_trace_bio - Add a trace for a bio oriented action + * @q: queue the io is for + * @bio: the source bio + * @what: the action + * + * Description: + * Records an action against a bio. Will log the bio offset + size. + * + **/ +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); +} + +/** + * blk_add_trace_generic - Add a trace for a generic action + * @q: queue the io is for + * @bio: the source bio + * @rw: the data direction + * @what: the action + * + * Description: + * Records a simple trace + * + **/ +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); +} + +/** + * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload + * @q: queue the io is for + * @what: the action + * @bio: the source bio + * @pdu: the integer payload + * + * Description: + * Adds a trace with some integer payload. This might be an unplug + * option given as the action, with the depth at unplug time given + * as the payload + * + **/ +static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, + struct bio *bio, unsigned int pdu) +{ + struct blk_trace *bt = q->blk_trace; + u64 rpdu = cpu_to_be64(pdu); + + if (likely(!bt)) + return; + + if (bio) + __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); + else + __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); +} + +/** + * blk_add_trace_remap - Add a trace for a remap operation + * @q: queue the io is for + * @bio: the source bio + * @dev: target device + * @from: source sector + * @to: target sector + * + * Description: + * Device mapper or raid target sometimes need to split a bio because + * it spans a stripe (or similar). Add a trace for that action. + * + **/ +static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, + dev_t dev, sector_t from, sector_t to) +{ + struct blk_trace *bt = q->blk_trace; + struct blk_io_trace_remap r; + + if (likely(!bt)) + return; + + r.device = cpu_to_be32(dev); + r.sector = cpu_to_be64(to); + + __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); +} + +#else /* !CONFIG_BLK_DEV_IO_TRACE */ +#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) +#define blk_trace_shutdown(q) do { } while (0) +#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) +#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) +#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) +#endif /* CONFIG_BLK_DEV_IO_TRACE */ + +#endif diff --git a/include/linux/compat_ioctl.h b/include/linux/compat_ioctl.h index ae7dfb7..efb518f 100644 --- a/include/linux/compat_ioctl.h +++ b/include/linux/compat_ioctl.h @@ -97,6 +97,10 @@ COMPATIBLE_IOCTL(BLKRRPART) COMPATIBLE_IOCTL(BLKFLSBUF) COMPATIBLE_IOCTL(BLKSECTSET) COMPATIBLE_IOCTL(BLKSSZGET) +COMPATIBLE_IOCTL(BLKTRACESTART) +COMPATIBLE_IOCTL(BLKTRACESTOP) +COMPATIBLE_IOCTL(BLKTRACESETUP) +COMPATIBLE_IOCTL(BLKTRACETEARDOWN) ULONG_IOCTL(BLKRASET) ULONG_IOCTL(BLKFRASET) /* RAID */ diff --git a/include/linux/fs.h b/include/linux/fs.h index f9c9dea..9b34a1b 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -197,6 +197,10 @@ 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 BLKTRACESETUP _IOWR(0x12,115,struct blk_user_trace_setup) +#define BLKTRACESTART _IO(0x12,116) +#define BLKTRACESTOP _IO(0x12,117) +#define BLKTRACETEARDOWN _IO(0x12,118) #define BMAP_IOCTL 1 /* obsolete - kept for compatibility */ #define FIBMAP _IO(0x00,1) /* bmap access */ diff --git a/include/linux/sched.h b/include/linux/sched.h index 62e6314..e60a91d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -706,6 +706,7 @@ struct task_struct { prio_array_t *array; unsigned short ioprio; + unsigned int btrace_seq; unsigned long sleep_avg; unsigned long long timestamp, last_ran; -- cgit v1.1