SUBDIR= aal add_route arp ash at autil awk \
backup badblocks banner basename binpackage \
- binpackages cal calendar \
+ binpackages btrace cal calendar \
cat cawf cd cdprobe checkhier chmem \
chmod chown chroot ci cksum cleantmp clear cmp co \
comm compress cp crc cron crontab cut date \
--- /dev/null
+PROG= btrace
+MAN=
+
+.include <bsd.prog.mk>
--- /dev/null
+/* Block trace command line tool */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <minix/types.h>
+#include <minix/btrace.h>
+#include <sys/ioc_block.h>
+
+static void usage(char *name)
+{
+ printf("usage:\n"
+ "%s start <device> <nr_entries>\n"
+ "%s stop <device> <file>\n"
+ "%s reset <device>\n"
+ "%s dump <file>\n",
+ name, name, name, name);
+
+ exit(EXIT_FAILURE);
+}
+
+static void btrace_start(char *device, int nr_entries)
+{
+ int r, ctl, devfd;
+ size_t size;
+
+ if ((devfd = open(device, O_RDONLY)) < 0) {
+ perror("device open");
+ exit(EXIT_FAILURE);
+ }
+
+ size = nr_entries;
+ if ((r = ioctl(devfd, BIOCTRACEBUF, &size)) < 0) {
+ perror("ioctl(BIOCTRACEBUF)");
+ exit(EXIT_FAILURE);
+ }
+
+ ctl = BTCTL_START;
+ if ((r = ioctl(devfd, BIOCTRACECTL, &ctl)) < 0) {
+ perror("ioctl(BIOCTRACECTL)");
+
+ size = 0;
+ ioctl(devfd, BIOCTRACEBUF, &size);
+
+ exit(EXIT_FAILURE);
+ }
+
+ close(devfd);
+}
+
+static void btrace_stop(char *device, char *file)
+{
+ btrace_entry buf[BTBUF_SIZE];
+ int r, ctl, devfd, outfd;
+ size_t size;
+
+ if ((devfd = open(device, O_RDONLY)) < 0) {
+ perror("device open");
+ exit(EXIT_FAILURE);
+ }
+
+ if ((outfd = open(file, O_CREAT|O_TRUNC|O_WRONLY, 0600)) < 0) {
+ perror("file open");
+ exit(EXIT_FAILURE);
+ }
+
+ ctl = BTCTL_STOP;
+ if ((r = ioctl(devfd, BIOCTRACECTL, &ctl)) < 0) {
+ perror("ioctl(BIOCTRACECTL)");
+ exit(EXIT_FAILURE);
+ }
+
+ for (;;) {
+ if ((r = ioctl(devfd, BIOCTRACEGET, buf)) < 0) {
+ perror("ioctl(BIOCTRACEGET)");
+ break;
+ }
+
+ if (r == 0) break;
+
+ size = r * sizeof(buf[0]);
+ if ((r = write(outfd, (char *) buf, size)) != size) {
+ if (r < 0) perror("write");
+ else fputs("short write\n", stderr);
+ }
+ }
+
+ close(outfd);
+
+ size = 0;
+ if ((r = ioctl(devfd, BIOCTRACEBUF, &size)) < 0) {
+ perror("ioctl(BIOCTRACEBUF)");
+ exit(EXIT_FAILURE);
+ }
+
+ close(devfd);
+}
+
+static void btrace_reset(char *device)
+{
+ size_t size;
+ int r, ctl, devfd;
+
+ if ((devfd = open(device, O_RDONLY)) < 0) {
+ perror("device open");
+ exit(EXIT_FAILURE);
+ }
+
+ ctl = BTCTL_STOP;
+ (void) ioctl(devfd, BIOCTRACECTL, &ctl);
+
+ size = 0;
+ if ((r = ioctl(devfd, BIOCTRACEBUF, &size)) < 0) {
+ perror("ioctl(BIOCTRACEBUF)");
+ exit(EXIT_FAILURE);
+ }
+
+ close(devfd);
+}
+
+static void dump_entry(btrace_entry *entry)
+{
+ switch (entry->request) {
+ case BTREQ_OPEN: printf("OPEN"); break;
+ case BTREQ_CLOSE: printf("CLOSE"); break;
+ case BTREQ_READ: printf("READ"); break;
+ case BTREQ_WRITE: printf("WRITE"); break;
+ case BTREQ_GATHER: printf("GATHER"); break;
+ case BTREQ_SCATTER: printf("SCATTER"); break;
+ case BTREQ_IOCTL: printf("IOCTL"); break;
+ }
+
+ printf(" request\n");
+
+ switch (entry->request) {
+ case BTREQ_OPEN:
+ printf("- access:\t%lx\n", entry->size);
+ break;
+ case BTREQ_READ:
+ case BTREQ_WRITE:
+ case BTREQ_GATHER:
+ case BTREQ_SCATTER:
+ printf("- position:\t%08lx%08lx\n",
+ ex64hi(entry->position), ex64lo(entry->position));
+ printf("- size:\t\t%u\n", entry->size);
+ printf("- flags:\t%x\n", entry->flags);
+ break;
+ case BTREQ_IOCTL:
+ printf("- request:\t%08x\n", entry->size);
+ break;
+ }
+
+ printf("- start:\t%u us\n", entry->start_time);
+ printf("- finish:\t%u us\n", entry->finish_time);
+ if (entry->result == BTRES_INPROGRESS)
+ printf("- result:\t(in progress)\n");
+ else
+ printf("- result:\t%d\n", entry->result);
+ printf("\n");
+}
+
+static void btrace_dump(char *file)
+{
+ btrace_entry buf[BTBUF_SIZE];
+ int i, r, infd;
+
+ if ((infd = open(file, O_RDONLY)) < 0) {
+ perror("open");
+ exit(EXIT_FAILURE);
+ }
+
+ for (;;) {
+ if ((r = read(infd, (char *) buf, sizeof(buf))) <= 0)
+ break;
+
+ r /= sizeof(buf[0]);
+
+ for (i = 0; i < r; i++)
+ dump_entry(&buf[i]);
+ }
+
+ if (r < 0) perror("read");
+
+ close(infd);
+}
+
+int main(int argc, char **argv)
+{
+ int num;
+ char *name = argv[0];
+
+ if (argc < 3) usage(name);
+
+ if (!strcmp(argv[1], "start")) {
+ if (argc < 4) usage(name);
+
+ num = atoi(argv[3]);
+
+ if (num <= 0) usage(name);
+
+ btrace_start(argv[2], num);
+ }
+ else if (!strcmp(argv[1], "stop")) {
+ if (argc < 4) usage(name);
+
+ btrace_stop(argv[2], argv[3]);
+ }
+ else if (!strcmp(argv[1], "reset")) {
+ btrace_reset(argv[2]);
+ }
+ else if (!strcmp(argv[1], "dump")) {
+ btrace_dump(argv[2]);
+ }
+ else usage(name);
+
+ return EXIT_SUCCESS;
+}
INCS+= minix/acpi.h minix/ansi.h minix/audio_fw.h minix/bitmap.h \
minix/bdev.h minix/blockdriver.h minix/blockdriver_mt.h \
+ minix/btrace.h \
minix/callnr.h minix/chardriver.h minix/com.h minix/compiler.h \
minix/config.h minix/const.h minix/cpufeature.h minix/crtso.h \
minix/debug.h minix/devio.h minix/devman.h minix/dmap.h \
*/
_PROTOTYPE( void blockdriver_announce, (void) );
-#ifndef _DRIVER_MT_API
+#ifndef _BLOCKDRIVER_MT_API
/* Additional functions for the singlethreaded version. These allow the driver
* to either use the stock driver_task(), or implement its own message loop.
* To avoid accidents, these functions are not exposed when minix/driver_mt.h
_PROTOTYPE( void blockdriver_terminate, (void) );
_PROTOTYPE( void blockdriver_task, (struct blockdriver *bdp) );
_PROTOTYPE( int blockdriver_mq_queue, (message *m_ptr, int status) );
-#endif /* !_DRIVER_MT_API */
+#endif /* !_BLOCKDRIVER_MT_API */
/* Parameters for the disk drive. */
#define SECTOR_SIZE 512 /* physical sector size in bytes */
#ifndef _MINIX_BLOCKDRIVER_MT_H
#define _MINIX_BLOCKDRIVER_MT_H
-#define DRIVER_MT_API 1 /* do not expose the singlethreaded API */
+#define BLOCKDRIVER_MT_API 1 /* do not expose the singlethreaded API */
#include <minix/blockdriver.h>
/* The maximum number of worker threads. */
-#define DRIVER_MT_MAX_WORKERS 32
+#define BLOCKDRIVER_MT_MAX_WORKERS 32
_PROTOTYPE( void blockdriver_mt_task, (struct blockdriver *driver_tab) );
_PROTOTYPE( void blockdriver_mt_sleep, (void) );
--- /dev/null
+#ifndef _MINIX_BTRACE_H
+#define _MINIX_BTRACE_H
+
+/* Control directives. */
+enum {
+ BTCTL_START,
+ BTCTL_STOP
+};
+
+/* Request codes. */
+enum {
+ BTREQ_OPEN,
+ BTREQ_CLOSE,
+ BTREQ_READ,
+ BTREQ_WRITE,
+ BTREQ_GATHER,
+ BTREQ_SCATTER,
+ BTREQ_IOCTL
+};
+
+/* Special result codes. */
+#define BTRES_INPROGRESS (-997)
+
+/* Block trace entry. */
+typedef struct {
+ u32_t request; /* request code; one of BTR_xxx */
+ u32_t size; /* request size, ioctl request, or access */
+ u64_t position; /* starting disk position */
+ u32_t flags; /* transfer flags */
+ i32_t result; /* request result; OK, bytes, or error */
+ u32_t start_time; /* request service start time (us) */
+ u32_t finish_time; /* request service completion time (us) */
+} btrace_entry; /* (32 bytes) */
+
+/* This is the number of btrace_entry structures copied out at once using the
+ * BIOCTRACEGET ioctl call.
+ */
+#define BTBUF_SIZE 1024
+
+#endif /* _MINIX_BTRACE_H */
.PATH: ${MINIXSRCDIR}/common/include/sys
INCS+= elf32.h elf64.h elf_common.h elf_generic.h \
- ioc_file.h ioc_tape.h ioc_disk.h \
+ ioc_block.h ioc_file.h ioc_tape.h ioc_disk.h \
ioc_memory.h ioc_sound.h ioc_tty.h \
kbdio.h mtio.h svrctl.h video.h vm.h procfs.h elf_core.h exec_elf.h
--- /dev/null
+/* sys/ioc_block.h - Block ioctl() command codes.
+ *
+ */
+
+#ifndef _S_I_BLOCK_H
+#define _S_I_BLOCK_H
+
+#include <minix/ioctl.h>
+#include <minix/btrace.h>
+
+#define BIOCTRACEBUF _IOW('b', 1, size_t)
+#define BIOCTRACECTL _IOW('b', 2, int)
+#define BIOCTRACEGET _IOR_BIG(3, btrace_entry[BTBUF_SIZE])
+
+#endif /* _S_I_BLOCK_H */
LIB= blockdriver
-SRCS= driver.c drvlib.c driver_st.c driver_mt.c mq.c event.c
+SRCS= driver.c drvlib.c driver_st.c driver_mt.c mq.c event.c trace.c
.if ${USE_STATECTL} != "no"
CPPFLAGS+= -DUSE_STATECTL
#include <minix/drivers.h>
#include <minix/blockdriver.h>
#include <minix/ds.h>
+#include <sys/ioc_block.h>
#include <sys/ioc_disk.h>
#include "driver.h"
#include "mq.h"
+#include "trace.h"
/* Management data for opened devices. */
PRIVATE int open_devs[MAX_NR_OPEN_DEVICES];
/*===========================================================================*
* do_vrdwt *
*===========================================================================*/
-PRIVATE int do_vrdwt(struct blockdriver *bdp, message *mp)
+PRIVATE int do_vrdwt(struct blockdriver *bdp, message *mp, thread_id_t id)
{
/* Carry out an device read or write to/from a vector of buffers. */
iovec_t iovec[NR_IOREQS];
return EINVAL;
}
- /* Check for overflow condition. */
+ /* Check for overflow condition, and update the size for block tracing. */
for (i = size = 0; i < nr_req; i++) {
if ((ssize_t) (size + iovec[i].iov_size) < size) return EINVAL;
size += iovec[i].iov_size;
}
+ trace_setsize(id, size);
+
/* Transfer bytes from/to the device. */
do_write = (mp->m_type == BDEV_SCATTER);
position = make64(mp->BDEV_POS_LO, mp->BDEV_POS_HI);
PRIVATE int do_ioctl(struct blockdriver *bdp, message *mp)
{
/* Carry out an I/O control request. For now, we handle setting/getting
- * partitions here, and let the driver handle any other requests.
+ * partitions here, forward block trace control requests to the tracing module,
+ * and let the driver handle any other requests. In the future, a stricter
+ * separation between block and disk I/O controls may become desirable, but we
+ * do not have any non-"disk" block drivers at this time.
*/
struct device *dv;
struct partition entry;
grant = mp->BDEV_GRANT;
switch (request) {
+ case BIOCTRACEBUF:
+ case BIOCTRACECTL:
+ case BIOCTRACEGET:
+ /* Block trace control. */
+ r = trace_ctl(minor, request, mp->m_source, grant);
+
+ break;
+
case DIOCSETP:
/* Copy just this one partition table entry. */
r = sys_safecopyfrom(mp->m_source, grant, 0, (vir_bytes) &entry,
/*===========================================================================*
* blockdriver_handle_request *
*===========================================================================*/
-PUBLIC int blockdriver_handle_request(struct blockdriver *bdp, message *m_ptr)
+PUBLIC int blockdriver_handle_request(struct blockdriver *bdp, message *m_ptr,
+ thread_id_t id)
{
/* Call the appropiate driver function, based on the type of request. Return
* the result code that is to be sent back to the caller, or EDONTREPLY if no
set_open_dev(m_ptr->BDEV_MINOR);
}
+ trace_start(id, m_ptr);
+
/* Call the appropriate function(s) for this request. */
switch (m_ptr->m_type) {
case BDEV_OPEN: r = do_open(bdp, m_ptr); break;
case BDEV_READ:
case BDEV_WRITE: r = do_rdwt(bdp, m_ptr); break;
case BDEV_GATHER:
- case BDEV_SCATTER: r = do_vrdwt(bdp, m_ptr); break;
+ case BDEV_SCATTER: r = do_vrdwt(bdp, m_ptr, id); break;
case BDEV_IOCTL: r = do_ioctl(bdp, m_ptr); break;
default:
if (bdp->bdr_other)
if (bdp->bdr_cleanup != NULL)
(*bdp->bdr_cleanup)();
+ trace_finish(id, r);
+
return r;
}
#ifndef _BLOCKDRIVER_DRIVER_H
#define _BLOCKDRIVER_DRIVER_H
+#define SINGLE_THREAD (0) /* single-thread ID */
+#define MAIN_THREAD (BLOCKDRIVER_MT_MAX_WORKERS) /* main thread ID */
+
_PROTOTYPE( void blockdriver_handle_notify, (struct blockdriver *bdp,
message *m_ptr) );
_PROTOTYPE( int blockdriver_handle_request, (struct blockdriver *bdp,
- message *m_ptr) );
+ message *m_ptr, thread_id_t thread) );
_PROTOTYPE( void blockdriver_reply, (message *m_ptr, int ipc_status,
int reply) );
PRIVATE mthread_key_t worker_key;
-PRIVATE worker_t worker[DRIVER_MT_MAX_WORKERS];
+PRIVATE worker_t worker[BLOCKDRIVER_MT_MAX_WORKERS];
-PRIVATE worker_t *exited[DRIVER_MT_MAX_WORKERS];
+PRIVATE worker_t *exited[BLOCKDRIVER_MT_MAX_WORKERS];
PRIVATE int num_exited = 0;
/*===========================================================================*
wp->state = STATE_RUNNING;
/* Handle the request, and send a reply. */
- r = blockdriver_handle_request(bdtab, &m);
+ r = blockdriver_handle_request(bdtab, &m, wp->id);
blockdriver_reply(&m, ipc_status, r);
}
*/
if (!IS_BDEV_RQ(m_ptr->m_type)) {
/* Process as 'other' message. */
- r = blockdriver_handle_request(bdtab, m_ptr);
+ r = blockdriver_handle_request(bdtab, m_ptr, MAIN_THREAD);
blockdriver_reply(m_ptr, ipc_status, r);
}
/* Start the thread if it is not already running. */
- assert(thread_id >= 0 && thread_id < DRIVER_MT_MAX_WORKERS);
+ assert(thread_id >= 0 && thread_id < BLOCKDRIVER_MT_MAX_WORKERS);
wp = &worker[thread_id];
bdtab = bdp;
- for (i = 0; i < DRIVER_MT_MAX_WORKERS; i++)
+ for (i = 0; i < BLOCKDRIVER_MT_MAX_WORKERS; i++)
worker[i].state = STATE_DEAD;
/* Initialize a per-thread key, where each worker thread stores its own
*/
worker_t *wp;
- assert(id >= 0 && id < DRIVER_MT_MAX_WORKERS);
+ assert(id >= 0 && id < BLOCKDRIVER_MT_MAX_WORKERS);
wp = &worker[id];
/* receive() interface for drivers with message queueing. */
/* Any queued messages? */
- if (mq_dequeue(MQ_SINGLE, m_ptr, status_ptr))
+ if (mq_dequeue(SINGLE_THREAD, m_ptr, status_ptr))
return OK;
/* Fall back to standard receive() interface otherwise. */
/* Do not reply to notifications. */
} else {
- r = blockdriver_handle_request(bdp, m_ptr);
+ r = blockdriver_handle_request(bdp, m_ptr, SINGLE_THREAD);
blockdriver_reply(m_ptr, ipc_status, r);
}
{
/* Queue a message for later processing. */
- return mq_enqueue(MQ_SINGLE, m, status);
+ return mq_enqueue(SINGLE_THREAD, m, status);
}
PRIVATE struct mq_cell pool[MQ_SIZE];
-PRIVATE STAILQ_HEAD(queue, mq_cell) queue[DRIVER_MT_MAX_WORKERS];
+PRIVATE STAILQ_HEAD(queue, mq_cell) queue[BLOCKDRIVER_MT_MAX_WORKERS];
PRIVATE STAILQ_HEAD(free_list, mq_cell) free_list;
/*===========================================================================*
STAILQ_INIT(&free_list);
- for (i = 0; i < DRIVER_MT_MAX_WORKERS; i++)
+ for (i = 0; i < BLOCKDRIVER_MT_MAX_WORKERS; i++)
STAILQ_INIT(&queue[i]);
for (i = 0; i < MQ_SIZE; i++)
*/
struct mq_cell *cell;
- assert(thread_id >= 0 && thread_id < DRIVER_MT_MAX_WORKERS);
+ assert(thread_id >= 0 && thread_id < BLOCKDRIVER_MT_MAX_WORKERS);
if (STAILQ_EMPTY(&free_list))
return FALSE;
*/
struct mq_cell *cell;
- assert(thread_id >= 0 && thread_id < DRIVER_MT_MAX_WORKERS);
+ assert(thread_id >= 0 && thread_id < BLOCKDRIVER_MT_MAX_WORKERS);
if (STAILQ_EMPTY(&queue[thread_id]))
return FALSE;
#ifndef _BLOCKDRIVER_MQ_H
#define _BLOCKDRIVER_MQ_H
-#define MQ_SINGLE 0 /* thread ID for single-threading */
-
_PROTOTYPE( void mq_init, (void) );
_PROTOTYPE( int mq_enqueue, (thread_id_t thread_id, const message *mess,
int ipc_status) );
--- /dev/null
+/* This file implements block level tracing support. */
+
+#include <minix/drivers.h>
+#include <minix/blockdriver_mt.h>
+#include <minix/btrace.h>
+#include <sys/ioc_block.h>
+#include <minix/minlib.h>
+#include <assert.h>
+
+#include "trace.h"
+
+#define NO_TRACEDEV ((dev_t) -1)
+#define NO_TIME ((u32_t) -1)
+
+PRIVATE int trace_enabled = FALSE;
+PRIVATE dev_t trace_dev = NO_TRACEDEV;
+PRIVATE btrace_entry *trace_buf = NULL;
+PRIVATE size_t trace_size = 0;
+PRIVATE size_t trace_pos;
+PRIVATE size_t trace_next;
+PRIVATE u64_t trace_tsc;
+
+/* Pointers to in-progress trace entries for each thread (all worker threads,
+ * plus one for the main thread). Each pointer is set to NULL whenever no
+ * operation is currently being traced for that thread, for whatever reason.
+ */
+PRIVATE btrace_entry *trace_ptr[BLOCKDRIVER_MT_MAX_WORKERS + 1] = { NULL };
+
+/*===========================================================================*
+ * trace_gettime *
+ *===========================================================================*/
+PRIVATE u32_t trace_gettime(void)
+{
+/* Return the current time, in microseconds since the start of the trace.
+ */
+ u64_t tsc;
+
+ assert(trace_enabled);
+
+ read_tsc_64(&tsc);
+
+ tsc = sub64(tsc, trace_tsc);
+
+ return tsc_64_to_micros(tsc);
+}
+
+/*===========================================================================*
+ * trace_ctl *
+ *===========================================================================*/
+PUBLIC int trace_ctl(dev_t minor, unsigned int request, endpoint_t endpt,
+ cp_grant_id_t grant)
+{
+/* Process a block trace control request.
+ */
+ size_t size;
+ int r, ctl, entries;
+
+ switch (request) {
+ case BIOCTRACEBUF:
+ /* The size cannot be changed when tracing is enabled. */
+ if (trace_enabled) return EBUSY;
+
+ /* Copy in the requested size. */
+ if ((r = sys_safecopyfrom(endpt, grant, 0, (vir_bytes) &size,
+ sizeof(size), D)) != OK)
+ return r;
+
+ if (size >= INT_MAX / sizeof(btrace_entry)) return EINVAL;
+
+ /* The size can only be set or reset, not changed. */
+ if (size > 0 && trace_size > 0) return EBUSY;
+
+ /* Allocate or free a buffer for tracing data. For future multi-device
+ * tracing support, the buffer is associated with a minor device.
+ */
+ if (size == 0) {
+ if (trace_dev == NO_TRACEDEV) return OK;
+
+ if (trace_dev != minor) return EINVAL;
+
+ free(trace_buf);
+
+ trace_dev = NO_TRACEDEV;
+ } else {
+ if ((trace_buf = malloc(size * sizeof(btrace_entry))) == NULL)
+ return errno;
+
+ trace_dev = minor;
+ }
+
+ trace_size = size;
+ trace_pos = 0;
+ trace_next = 0;
+
+ return OK;
+
+ case BIOCTRACECTL:
+ /* We can only start/stop tracing if the given device has a trace
+ * buffer associated with it.
+ */
+ if (trace_dev != minor) return EINVAL;
+
+ /* Copy in the request code. */
+ if ((r = sys_safecopyfrom(endpt, grant, 0, (vir_bytes) &ctl,
+ sizeof(ctl), D)) != OK)
+ return r;
+
+ /* Start or stop tracing. */
+ switch (ctl) {
+ case BTCTL_START:
+ if (trace_enabled) return EBUSY;
+
+ read_tsc_64(&trace_tsc);
+
+ trace_enabled = TRUE;
+
+ break;
+
+ case BTCTL_STOP:
+ if (!trace_enabled) return EINVAL;
+
+ trace_enabled = FALSE;
+
+ /* Cancel all ongoing trace operations. */
+ memset(trace_ptr, 0, sizeof(trace_ptr));
+
+ break;
+
+ default:
+ return EINVAL;
+ }
+
+ return OK;
+
+ case BIOCTRACEGET:
+ /* We can only retrieve tracing entries if the given device has a trace
+ * buffer associated with it.
+ */
+ if (trace_dev != minor) return EINVAL;
+
+ if (trace_enabled) return EBUSY;
+
+ /* How much can we copy out? */
+ entries = MIN(trace_pos - trace_next,
+ _MINIX_IOCTL_SIZE_BIG(request) / sizeof(btrace_entry));
+
+ if (entries == 0)
+ return 0;
+
+ if ((r = sys_safecopyto(endpt, grant, 0,
+ (vir_bytes) &trace_buf[trace_next],
+ entries * sizeof(btrace_entry), D)) != OK)
+ return r;
+
+ trace_next += entries;
+
+ return entries;
+ }
+
+ return EINVAL;
+}
+
+/*===========================================================================*
+ * trace_start *
+ *===========================================================================*/
+PUBLIC void trace_start(thread_id_t id, message *m_ptr)
+{
+/* Start creating a trace entry.
+ */
+ btrace_entry *entry;
+ int req;
+ u64_t pos;
+ size_t size;
+ int flags;
+
+ if (!trace_enabled || trace_dev != m_ptr->BDEV_MINOR) return;
+
+ assert(id >= 0 && id < BLOCKDRIVER_MT_MAX_WORKERS + 1);
+
+ if (trace_pos == trace_size)
+ return;
+
+ switch (m_ptr->m_type) {
+ case BDEV_OPEN: req = BTREQ_OPEN; break;
+ case BDEV_CLOSE: req = BTREQ_CLOSE; break;
+ case BDEV_READ: req = BTREQ_READ; break;
+ case BDEV_WRITE: req = BTREQ_WRITE; break;
+ case BDEV_GATHER: req = BTREQ_GATHER; break;
+ case BDEV_SCATTER: req = BTREQ_SCATTER; break;
+ case BDEV_IOCTL: req = BTREQ_IOCTL; break;
+ default: return;
+ }
+
+ switch (m_ptr->m_type) {
+ case BDEV_OPEN:
+ case BDEV_CLOSE:
+ pos = cvu64(0);
+ size = m_ptr->BDEV_ACCESS;
+ flags = 0;
+
+ break;
+
+ case BDEV_READ:
+ case BDEV_WRITE:
+ case BDEV_GATHER:
+ case BDEV_SCATTER:
+ pos = make64(m_ptr->BDEV_POS_LO, m_ptr->BDEV_POS_HI);
+ size = m_ptr->BDEV_COUNT;
+ flags = m_ptr->BDEV_FLAGS;
+
+ break;
+
+ case BDEV_IOCTL:
+ pos = cvu64(0);
+ size = m_ptr->BDEV_REQUEST;
+ flags = 0;
+
+ /* Do not log trace control requests. */
+ switch (size) {
+ case BIOCTRACEBUF:
+ case BIOCTRACECTL:
+ case BIOCTRACEGET:
+ return;
+ }
+
+ break;
+
+ default:
+ /* Do not log any other messages. */
+ return;
+ }
+
+ entry = &trace_buf[trace_pos];
+ entry->request = req;
+ entry->size = size;
+ entry->position = pos;
+ entry->flags = flags;
+ entry->result = BTRES_INPROGRESS;
+ entry->start_time = trace_gettime();
+ entry->finish_time = NO_TIME;
+
+ trace_ptr[id] = entry;
+ trace_pos++;
+}
+
+/*===========================================================================*
+ * trace_setsize *
+ *===========================================================================*/
+PUBLIC void trace_setsize(thread_id_t id, size_t size)
+{
+/* Set the current trace entry's actual (byte) size, for vector requests.
+ */
+ btrace_entry *entry;
+
+ if (!trace_enabled) return;
+
+ assert(id >= 0 && id < BLOCKDRIVER_MT_MAX_WORKERS + 1);
+
+ if ((entry = trace_ptr[id]) == NULL) return;
+
+ entry->size = size;
+}
+
+/*===========================================================================*
+ * trace_finish *
+ *===========================================================================*/
+PUBLIC void trace_finish(thread_id_t id, int result)
+{
+/* Finish a trace entry.
+ */
+ btrace_entry *entry;
+
+ if (!trace_enabled) return;
+
+ assert(id >= 0 && id < BLOCKDRIVER_MT_MAX_WORKERS + 1);
+
+ if ((entry = trace_ptr[id]) == NULL) return;
+
+ entry->result = result;
+ entry->finish_time = trace_gettime();
+
+ trace_ptr[id] = NULL;
+}
--- /dev/null
+#ifndef _BLOCKDRIVER_TRACE_H
+#define _BLOCKDRIVER_TRACE_H
+
+_PROTOTYPE( int trace_ctl, (dev_t minor, unsigned int request,
+ endpoint_t endpt, cp_grant_id_t grant));
+
+_PROTOTYPE( void trace_start, (thread_id_t thread_id, message *m_ptr));
+_PROTOTYPE( void trace_setsize, (thread_id_t thread_id, size_t size));
+_PROTOTYPE( void trace_finish, (thread_id_t thread_id, int r));
+
+#endif /* _BLOCKDRIVER_TRACE_H */
-MAN= add_route.8 backup.8 badblocks.8 boot.8 \
+MAN= add_route.8 backup.8 badblocks.8 boot.8 btrace.8 \
cdprobe.8 checkhier.8 chown.8 cleantmp.8 config.8 cron.8 \
dhcpd.8 diskctl.8 dosminix.8 elvprsv.8 fdisk.8 fingerd.8 ftpd.8 \
getty.8 halt.8 hgfs.8 httpd.8 ifconfig.8 inet.8 init.8 \
--- /dev/null
+.TH BTRACE 8
+.SH NAME
+btrace \- block-level tracing interface
+.SH SYNOPSIS
+\fBbtrace\fR \fBstart\fR \fIdevice\fR \fIentries\fR
+.PP
+\fBbtrace\fR \fBstop\fR \fIdevice\fR \fIfile\fR
+.PP
+\fBbtrace\fR \fBreset\fR \fIdevice\fR
+.PP
+\fBbtrace\fR \fBdump\fR \fIfile\fR
+.SH DESCRIPTION
+The \fBbtrace\fR tool is the user interface to MINIX3's block-level tracing
+facility. It allows one to start, stop, and reset tracing, and dump a trace
+output file in a somewhat human-readable format.
+.SH COMMANDS
+.TP 10
+\fBstart\fR
+This command starts tracing all block requests on the given \fIdevice\fR. Each
+block request takes up one entry in the log. The \fIentries\fR parameter
+specifies the allocation side of the log in the driver process, in number of
+(32-byte) entries. Once the log is full, no more entries will be added.
+.TP 10
+\fBstop\fR
+This command stops tracing on the given \fIdevice\fR, and dumps the resulting
+log to the given output \fIfile\fR.
+.TP 10
+\fBreset\fR
+This command stops tracing on the given \fIdevice\fR and resets the state of
+the block tracer. This should be useful only in emergency situations.
+.TP 10
+\fBdump\fR
+Dump the contents of a log file generated earlier with \fBbtrace stop\fR, in
+human-readable format. Heavy users of the block tracing facility will probably
+want to write their own tools for parsing and visualizing dump files.
+.SH LIMITATIONS
+Only one block device can be traced per driver at once. It is therefore also
+not possible to trace a device and all its partitions at the same time. The
+tracing facility has been designed for tracing activity of a single file
+system, in which case these limitations are not important.
+.PP
+The log will always start with a \fIclose\fR operation on the device, since
+\fBbtrace\fR closes the file descriptor used to instruct the driver to start
+tracing. Similarly, for logs that have not already filled up during tracing,
+the last entry will be a \fBbtrace\fR-triggered \fIopen\fR operation.
+.SH EXAMPLES
+.TP 35
+.B btrace start /dev/c2d0 10240
+# Start a block trace on c2d0.
+.TP 35
+.B btrace stop /dev/c2d0 outfile
+# Stop the block trace on c2d0.
+.TP 35
+.B btrace dump outfile
+# View the output of the trace.
+.SH "SEE ALSO"
+.BR ioctl (2).
+.SH AUTHOR
+David van Moolenbroek <david@minix3.org>
