+++ /dev/null
-/*
- * syslet engine
- *
- * IO engine that does regular pread(2)/pwrite(2) to transfer data, but
- * with syslets to make the execution async.
- *
- */
-#include <stdio.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <errno.h>
-#include <assert.h>
-#include <malloc.h>
-#include <asm/unistd.h>
-
-#include "../fio.h"
-#include "../lib/fls.h"
-
-#ifdef FIO_HAVE_SYSLET
-
-#ifdef __NR_pread64
-#define __NR_fio_pread __NR_pread64
-#define __NR_fio_pwrite __NR_pwrite64
-#else
-#define __NR_fio_pread __NR_pread
-#define __NR_fio_pwrite __NR_pwrite
-#endif
-
-struct syslet_data {
- struct io_u **events;
- unsigned int nr_events;
-
- struct syslet_ring *ring;
- unsigned int ring_mask;
- void *stack;
-};
-
-static void fio_syslet_add_event(struct thread_data *td, struct io_u *io_u)
-{
- struct syslet_data *sd = td->io_ops->data;
-
- assert(sd->nr_events < td->o.iodepth);
- sd->events[sd->nr_events++] = io_u;
-}
-
-static void fio_syslet_add_events(struct thread_data *td, unsigned int nr)
-{
- struct syslet_data *sd = td->io_ops->data;
- unsigned int i, uidx;
-
- uidx = sd->ring->user_tail;
- read_barrier();
-
- for (i = 0; i < nr; i++) {
- unsigned int idx = (i + uidx) & sd->ring_mask;
- struct syslet_completion *comp = &sd->ring->comp[idx];
- struct io_u *io_u = (struct io_u *) (long) comp->caller_data;
- long ret;
-
- ret = comp->status;
- if (ret <= 0) {
- io_u->resid = io_u->xfer_buflen;
- io_u->error = -ret;
- } else {
- io_u->resid = io_u->xfer_buflen - ret;
- io_u->error = 0;
- }
-
- fio_syslet_add_event(td, io_u);
- }
-}
-
-static void fio_syslet_wait_for_events(struct thread_data *td)
-{
- struct syslet_data *sd = td->io_ops->data;
- struct syslet_ring *ring = sd->ring;
-
- do {
- unsigned int kh = ring->kernel_head;
- int ret;
-
- /*
- * first reap events that are already completed
- */
- if (ring->user_tail != kh) {
- unsigned int nr = kh - ring->user_tail;
-
- fio_syslet_add_events(td, nr);
- ring->user_tail = kh;
- break;
- }
-
- /*
- * block waiting for at least one event
- */
- ret = syscall(__NR_syslet_ring_wait, ring, ring->user_tail);
- assert(!ret);
- } while (1);
-}
-
-static int fio_syslet_getevents(struct thread_data *td, unsigned int min,
- unsigned int fio_unused max,
- struct timespec fio_unused *t)
-{
- struct syslet_data *sd = td->io_ops->data;
- long ret;
-
- /*
- * While we have less events than requested, block waiting for them
- * (if we have to, there may already be more completed events ready
- * for us - see fio_syslet_wait_for_events()
- */
- while (sd->nr_events < min)
- fio_syslet_wait_for_events(td);
-
- ret = sd->nr_events;
- sd->nr_events = 0;
- return ret;
-}
-
-static struct io_u *fio_syslet_event(struct thread_data *td, int event)
-{
- struct syslet_data *sd = td->io_ops->data;
-
- return sd->events[event];
-}
-
-static void fio_syslet_prep_sync(struct fio_file *f,
- struct indirect_registers *regs)
-{
- FILL_IN(*regs, __NR_fsync, (long) f->fd);
-}
-
-static void fio_syslet_prep_datasync(struct fio_file *f,
- struct indirect_registers *regs)
-{
- FILL_IN(*regs, __NR_fdatasync, (long) f->fd);
-}
-
-static void fio_syslet_prep_rw(struct io_u *io_u, struct fio_file *f,
- struct indirect_registers *regs)
-{
- long nr;
-
- /*
- * prepare rw
- */
- if (io_u->ddir == DDIR_READ)
- nr = __NR_fio_pread;
- else
- nr = __NR_fio_pwrite;
-
- FILL_IN(*regs, nr, (long) f->fd, (long) io_u->xfer_buf,
- (long) io_u->xfer_buflen, (long) io_u->offset);
-}
-
-static void fio_syslet_prep(struct io_u *io_u, struct indirect_registers *regs)
-{
- struct fio_file *f = io_u->file;
-
- if (io_u->ddir == DDIR_SYNC)
- fio_syslet_prep_sync(f, regs);
- else if (io_u->ddir == DDIR_DATASYNC)
- fio_syslet_prep_datasync(f, regs);
- else
- fio_syslet_prep_rw(io_u, f, regs);
-}
-
-static void ret_func(void)
-{
- syscall(__NR_exit);
-}
-
-static int fio_syslet_queue(struct thread_data *td, struct io_u *io_u)
-{
- struct syslet_data *sd = td->io_ops->data;
- union indirect_params params;
- struct indirect_registers regs;
- int ret;
-
- fio_ro_check(td, io_u);
-
- memset(¶ms, 0, sizeof(params));
- fill_syslet_args(¶ms.syslet, sd->ring, (long)io_u, ret_func, sd->stack);
-
- fio_syslet_prep(io_u, ®s);
-
- ret = syscall(__NR_indirect, ®s, ¶ms, sizeof(params), 0);
- if (ret == (int) io_u->xfer_buflen) {
- /*
- * completed sync, account. this also catches fsync().
- */
- return FIO_Q_COMPLETED;
- } else if (ret < 0) {
- /*
- * queued for async execution
- */
- if (errno == ESYSLETPENDING)
- return FIO_Q_QUEUED;
- }
-
- io_u->error = errno;
- td_verror(td, io_u->error, "xfer");
- return FIO_Q_COMPLETED;
-}
-
-static int check_syslet_support(struct syslet_data *sd)
-{
- union indirect_params params;
- struct indirect_registers regs;
- pid_t pid, my_pid = getpid();
-
- memset(¶ms, 0, sizeof(params));
- fill_syslet_args(¶ms.syslet, sd->ring, 0, ret_func, sd->stack);
-
- FILL_IN(regs, __NR_getpid);
-
- pid = syscall(__NR_indirect, ®s, ¶ms, sizeof(params), 0);
- if (pid == my_pid)
- return 0;
-
- return 1;
-}
-
-static void fio_syslet_cleanup(struct thread_data *td)
-{
- struct syslet_data *sd = td->io_ops->data;
-
- if (sd) {
- free(sd->events);
- free(sd->ring);
- free(sd);
- }
-}
-
-static int fio_syslet_init(struct thread_data *td)
-{
- struct syslet_data *sd;
- void *ring = NULL, *stack = NULL;
- unsigned int ring_size, ring_nr;
-
- sd = malloc(sizeof(*sd));
- memset(sd, 0, sizeof(*sd));
-
- sd->events = malloc(sizeof(struct io_u *) * td->o.iodepth);
- memset(sd->events, 0, sizeof(struct io_u *) * td->o.iodepth);
-
- /*
- * The ring needs to be a power-of-2, so round it up if we have to
- */
- ring_nr = td->o.iodepth;
- if (ring_nr & (ring_nr - 1))
- ring_nr = 1 << __fls(ring_nr);
-
- ring_size = sizeof(struct syslet_ring) +
- ring_nr * sizeof(struct syslet_completion);
- if (posix_memalign(&ring, sizeof(uint64_t), ring_size))
- goto err_mem;
- if (posix_memalign(&stack, page_size, page_size))
- goto err_mem;
-
- sd->ring = ring;
- sd->ring_mask = ring_nr - 1;
- sd->stack = stack;
-
- memset(sd->ring, 0, ring_size);
- sd->ring->elements = ring_nr;
-
- if (!check_syslet_support(sd)) {
- td->io_ops->data = sd;
- return 0;
- }
-
- log_err("fio: syslets do not appear to work\n");
-err_mem:
- free(sd->events);
- if (ring)
- free(ring);
- if (stack)
- free(stack);
- free(sd);
- return 1;
-}
-
-static struct ioengine_ops ioengine = {
- .name = "syslet-rw",
- .version = FIO_IOOPS_VERSION,
- .init = fio_syslet_init,
- .queue = fio_syslet_queue,
- .getevents = fio_syslet_getevents,
- .event = fio_syslet_event,
- .cleanup = fio_syslet_cleanup,
- .open_file = generic_open_file,
- .close_file = generic_close_file,
- .get_file_size = generic_get_file_size,
-};
-
-#else /* FIO_HAVE_SYSLET */
-
-/*
- * When we have a proper configure system in place, we simply wont build
- * and install this io engine. For now install a crippled version that
- * just complains and fails to load.
- */
-static int fio_syslet_init(struct thread_data fio_unused *td)
-{
- log_err("fio: syslet not available\n");
- return 1;
-}
-
-static struct ioengine_ops ioengine = {
- .name = "syslet-rw",
- .version = FIO_IOOPS_VERSION,
- .init = fio_syslet_init,
-};
-
-#endif /* FIO_HAVE_SYSLET */
-
-static void fio_init fio_syslet_register(void)
-{
- register_ioengine(&ioengine);
-}
-
-static void fio_exit fio_syslet_unregister(void)
-{
- unregister_ioengine(&ioengine);
-}
projects / fio.git / blobdiff