From ea952fcaf26e4a0d2bdefc8c7c67dc4f0b3ceb15 Mon Sep 17 00:00:00 2001 From: Jim Harris Date: Wed, 23 Aug 2017 15:40:22 -0700 Subject: [PATCH] bdev/split: remove resubmit logic Issue each I/O to the base bdev as a new discrete I/O rather than resubmitting the original I/O. This enables some upcoming changes to better handle queueing and reset-related work at the generic bdev layer, which will also deprecate the resubmit I/O logic. Signed-off-by: Jim Harris Change-Id: Ic1caa89014981e948edfec5e8eaaacd41a73d49c Reviewed-on: https://review.gerrithub.io/375495 Reviewed-by: Daniel Verkamp Tested-by: SPDK Automated Test System Reviewed-by: Ben Walker --- lib/bdev/split/vbdev_split.c | 111 ++++++++++++++++++++--------------- 1 file changed, 65 insertions(+), 46 deletions(-) diff --git a/lib/bdev/split/vbdev_split.c b/lib/bdev/split/vbdev_split.c index 6fff374fc..e7fbadc51 100644 --- a/lib/bdev/split/vbdev_split.c +++ b/lib/bdev/split/vbdev_split.c @@ -43,6 +43,7 @@ #include "spdk/endian.h" #include "spdk/string.h" #include "spdk/io_channel.h" +#include "spdk/util.h" #include "spdk_internal/bdev.h" #include "spdk_internal/log.h" @@ -67,75 +68,70 @@ struct split_disk { static TAILQ_HEAD(, split_disk) g_split_disks = TAILQ_HEAD_INITIALIZER(g_split_disks); -static void -split_read(struct split_disk *split_disk, struct spdk_bdev_io *bdev_io) -{ - bdev_io->u.read.offset += split_disk->offset_bytes; -} +struct split_channel { + struct split_disk *disk; + struct spdk_io_channel *base_ch; +}; static void -split_write(struct split_disk *split_disk, struct spdk_bdev_io *bdev_io) -{ - bdev_io->u.write.offset += split_disk->offset_bytes; -} - -static void -split_unmap(struct split_disk *split_disk, struct spdk_bdev_io *bdev_io) -{ - bdev_io->u.unmap.offset += split_disk->offset_bytes; -} - -static void -split_flush(struct split_disk *split_disk, struct spdk_bdev_io *bdev_io) -{ - bdev_io->u.flush.offset += split_disk->offset_bytes; -} - -static void -_vbdev_split_complete_reset(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg) +vbdev_split_complete_io(struct spdk_bdev_io *bdev_io, bool success, void *cb_arg) { struct spdk_bdev_io *split_io = cb_arg; - struct spdk_io_channel *base_ch = *(struct spdk_io_channel **)split_io->driver_ctx; + int status = success ? SPDK_BDEV_IO_STATUS_SUCCESS : SPDK_BDEV_IO_STATUS_FAILED; - spdk_put_io_channel(base_ch); - spdk_bdev_io_complete(split_io, success); + spdk_bdev_io_complete(split_io, status); spdk_bdev_free_io(bdev_io); } static void vbdev_split_submit_request(struct spdk_io_channel *ch, struct spdk_bdev_io *bdev_io) { - struct split_disk *split_disk = bdev_io->bdev->ctxt; - struct spdk_io_channel *base_ch; + struct split_channel *split_ch = spdk_io_channel_get_ctx(ch); + struct split_disk *split_disk = split_ch->disk; + struct spdk_io_channel *base_ch = split_ch->base_ch; + struct spdk_bdev_desc *base_desc = split_disk->base->desc; + uint64_t offset; + int rc = 0; /* Modify the I/O to adjust for the offset within the base bdev. */ switch (bdev_io->type) { case SPDK_BDEV_IO_TYPE_READ: - split_read(split_disk, bdev_io); + offset = bdev_io->u.read.offset + split_disk->offset_bytes; + rc = spdk_bdev_readv(base_desc, base_ch, bdev_io->u.read.iovs, + bdev_io->u.read.iovcnt, offset, + bdev_io->u.read.len, vbdev_split_complete_io, + bdev_io); break; case SPDK_BDEV_IO_TYPE_WRITE: - split_write(split_disk, bdev_io); + offset = bdev_io->u.write.offset + split_disk->offset_bytes; + rc = spdk_bdev_writev(base_desc, base_ch, bdev_io->u.write.iovs, + bdev_io->u.write.iovcnt, offset, + bdev_io->u.write.len, vbdev_split_complete_io, + bdev_io); break; case SPDK_BDEV_IO_TYPE_UNMAP: - split_unmap(split_disk, bdev_io); + offset = bdev_io->u.unmap.offset + split_disk->offset_bytes; + rc = spdk_bdev_unmap(base_desc, base_ch, offset, bdev_io->u.unmap.len, + vbdev_split_complete_io, bdev_io); break; case SPDK_BDEV_IO_TYPE_FLUSH: - split_flush(split_disk, bdev_io); + offset = bdev_io->u.flush.offset + split_disk->offset_bytes; + rc = spdk_bdev_flush(base_desc, base_ch, offset, bdev_io->u.flush.len, + vbdev_split_complete_io, bdev_io); break; case SPDK_BDEV_IO_TYPE_RESET: - base_ch = spdk_get_io_channel(split_disk->base->bdev); - *(struct spdk_io_channel **)bdev_io->driver_ctx = base_ch; - spdk_bdev_reset(split_disk->base->desc, base_ch, - _vbdev_split_complete_reset, bdev_io); - return; + rc = spdk_bdev_reset(split_disk->base->desc, base_ch, + vbdev_split_complete_io, bdev_io); + break; default: SPDK_ERRLOG("split: unknown I/O type %d\n", bdev_io->type); spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED); return; } - /* Submit the modified I/O to the underlying bdev. */ - spdk_bdev_io_resubmit(bdev_io, split_disk->base->desc); + if (rc != 0) { + spdk_bdev_io_complete(bdev_io, SPDK_BDEV_IO_STATUS_FAILED); + } } static void @@ -174,6 +170,7 @@ vbdev_split_free(struct split_disk *split_disk) split_base = split_disk->base; + spdk_io_device_unregister(&split_disk->base, NULL); TAILQ_REMOVE(&g_split_disks, split_disk, tailq); free(split_disk->disk.name); free(split_disk); @@ -218,7 +215,7 @@ vbdev_split_get_io_channel(void *ctx) { struct split_disk *split_disk = ctx; - return split_disk->base->bdev->fn_table->get_io_channel(split_disk->base->bdev); + return spdk_get_io_channel(&split_disk->base); } static int @@ -247,6 +244,29 @@ static struct spdk_bdev_fn_table vbdev_split_fn_table = { .dump_config_json = vbdev_split_dump_config_json, }; +static int +split_channel_create_cb(void *io_device, void *ctx_buf) +{ + struct split_disk *disk = SPDK_CONTAINEROF(io_device, struct split_disk, base); + struct split_channel *ch = ctx_buf; + + ch->disk = disk; + ch->base_ch = spdk_bdev_get_io_channel(disk->base->desc); + if (ch->base_ch == NULL) { + return -1; + } + + return 0; +} + +static void +split_channel_destroy_cb(void *io_device, void *ctx_buf) +{ + struct split_channel *ch = ctx_buf; + + spdk_put_io_channel(ch->base_ch); +} + static int vbdev_split_create(struct spdk_bdev *base_bdev, uint64_t split_count, uint64_t split_size_mb) { @@ -347,6 +367,9 @@ vbdev_split_create(struct spdk_bdev *base_bdev, uint64_t split_count, uint64_t s vbdev_split_base_get_ref(split_base, d); + spdk_io_device_register(&d->base, split_channel_create_cb, split_channel_destroy_cb, + sizeof(struct split_channel)); + spdk_vbdev_register(&d->disk, &base_bdev, 1); TAILQ_INSERT_TAIL(&g_split_disks, d, tailq); @@ -447,11 +470,7 @@ vbdev_split_fini(void) static int vbdev_split_get_ctx_size(void) { - /* - * Note: this context is only used for RESET operations, since it is the only - * I/O type that does not just resubmit to the base bdev. - */ - return sizeof(struct spdk_io_channel *); + return 0; } SPDK_BDEV_MODULE_REGISTER(split, vbdev_split_init, vbdev_split_fini, NULL,