Attachment 15960 Details for Bug 14361 – PROTOTYPE !!! wip fix for master.

[patch] PROTOTYPE !!! wip fix for master.

0001-WIP-io_uring-short-read-fix.patch (text/plain), 8.57 KB, created by Jeremy Allison on 2020-05-08 04:08:42 UTC

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Creator: Jeremy Allison

Created: 2020-05-08 04:08:42 UTC

Size: 8.57 KB

patch

obsolete

>From baac8d196cf72a6264f865ceb7fd93f0d903609b Mon Sep 17 00:00:00 2001
>From: Jeremy Allison <jra@samba.org>
>Date: Thu, 7 May 2020 18:35:14 -0700
>Subject: [PATCH] WIP: io_uring short read fix.
>
>Signed-off-by: Jeremy Allison <jra@samba.org>
>---
> source3/modules/vfs_io_uring.c | 183 ++++++++++++++++++++++++++++++++-
> 1 file changed, 181 insertions(+), 2 deletions(-)
>
>diff --git a/source3/modules/vfs_io_uring.c b/source3/modules/vfs_io_uring.c
>index 378e48d112f..3a53a955a11 100644
>--- a/source3/modules/vfs_io_uring.c
>+++ b/source3/modules/vfs_io_uring.c
>@@ -32,15 +32,24 @@ struct vfs_io_uring_request;
> 
> struct vfs_io_uring_config {
> 	struct io_uring uring;
>+	struct tevent_context *ev;
> 	struct tevent_fd *fde;
>+	struct tevent_immediate *im;
> 	struct vfs_io_uring_request *queue;
> 	struct vfs_io_uring_request *pending;
> };
> 
>+enum vfs_io_uring_opcode {
>+	VFS_IO_URING_PREAD,
>+	VFS_IO_URING_PWRITE,
>+	VFS_IO_URING_FSYNC
>+};
>+
> struct vfs_io_uring_request {
> 	struct vfs_io_uring_request *prev, *next;
> 	struct vfs_io_uring_request **list_head;
> 	struct vfs_io_uring_config *config;
>+	enum vfs_io_uring_opcode opcode;
> 	struct tevent_req *req;
> 	void *state;
> 	struct io_uring_sqe sqe;
>@@ -147,6 +156,10 @@ static void vfs_io_uring_fd_handler(struct tevent_context *ev,
> 				    uint16_t flags,
> 				    void *private_data);
> 
>+static void vfs_io_uring_reschedule_run_handler(struct tevent_context *ctx,
>+						struct tevent_immediate *im,
>+						void *private_data);
>+
> static int vfs_io_uring_connect(vfs_handle_struct *handle, const char *service,
> 			    const char *user)
> {
>@@ -216,9 +229,56 @@ static int vfs_io_uring_connect(vfs_handle_struct *handle, const char *service,
> 		return -1;
> 	}
> 
>+	config->ev = handle->conn->sconn->ev_ctx;
>+
>+	config->im = tevent_create_immediate(config);
>+	if (config->im == NULL) {
>+		ret = errno;
>+		SMB_VFS_NEXT_DISCONNECT(handle);
>+		errno = ret;
>+		return -1;
>+	}
> 	return 0;
> }
> 
>+static bool is_io_uring_pread_complete(struct vfs_io_uring_request *cur,
>+				       const struct io_uring_cqe *cqe);
>+
>+#if 0
>+static bool is_io_uring_pwrite_complete(struct vfs_io_uring_request *cur,
>+					const struct io_uring_cqe *cqe);
>+#endif
>+
>+/*
>+ * Return true if it was a pread/pwrite and the bytes transferred
>+ * are less than requested.
>+ */
>+
>+static bool vfs_io_uring_complete(struct vfs_io_uring_request *cur,
>+				  const struct io_uring_cqe *cqe)
>+{
>+	if (cur->opcode == VFS_IO_URING_PREAD) {
>+		return is_io_uring_pread_complete(cur, cqe);
>+	}
>+#if 0
>+	} else if (cur->opcode == VFS_IO_URING_PWRITE) {
>+		return is_io_uring_pwrite_complete(cur, cqe);
>+	}
>+#endif
>+	return true;
>+}
>+
>+static void vfs_io_uring_pread_op_reschedule(struct vfs_io_uring_config *config,
>+					     struct vfs_io_uring_request *cur);
>+
>+static void vfs_io_uring_op_reschedule(struct vfs_io_uring_config *config,
>+				       struct vfs_io_uring_request *cur)
>+{
>+	if (cur->opcode == VFS_IO_URING_PREAD) {
>+		vfs_io_uring_pread_op_reschedule(config, cur);
>+	}
>+}
>+
> static void vfs_io_uring_queue_run(struct vfs_io_uring_config *config)
> {
> 	struct vfs_io_uring_request *cur = NULL, *next = NULL;
>@@ -228,6 +288,7 @@ static void vfs_io_uring_queue_run(struct vfs_io_uring_config *config)
> 	struct timespec start_time;
> 	struct timespec end_time;
> 	int ret;
>+	bool need_resubmit = false;
> 
> 	PROFILE_TIMESTAMP(&start_time);
> 
>@@ -269,11 +330,34 @@ static void vfs_io_uring_queue_run(struct vfs_io_uring_config *config)
> 
> 	io_uring_for_each_cqe(&config->uring, cqhead, cqe) {
> 		cur = (struct vfs_io_uring_request *)io_uring_cqe_get_data(cqe);
>-		vfs_io_uring_finish_req(cur, cqe, end_time, __location__);
>+		if (vfs_io_uring_complete(cur, cqe)) {
>+			/* Done. */
>+			vfs_io_uring_finish_req(cur, cqe, end_time, __location__);
>+		} else {
>+			/* Take us off the pending list. */
>+			DLIST_REMOVE(config->pending, cur);
>+			cur->list_head = NULL;
>+
>+			vfs_io_uring_op_reschedule(config, cur);
>+
>+			/* Put us back on the queued list. */
>+			DLIST_ADD_END(config->queue, cur);
>+			cur->list_head = &config->queue;
>+
>+			need_resubmit = true;
>+		}
> 		nr++;
> 	}
> 
> 	io_uring_cq_advance(&config->uring, nr);
>+
>+	if (need_resubmit) {
>+		/* This is essentially the same as GOTO top, but cleaner :-). */
>+		tevent_schedule_immediate(config->im,
>+					  config->ev,
>+					  vfs_io_uring_reschedule_run_handler,
>+					  config);
>+	}
> }
> 
> static void vfs_io_uring_fd_handler(struct tevent_context *ev,
>@@ -291,9 +375,25 @@ static void vfs_io_uring_fd_handler(struct tevent_context *ev,
> 	vfs_io_uring_queue_run(config);
> }
> 
>+static void vfs_io_uring_reschedule_run_handler(struct tevent_context *ctx,
>+						struct tevent_immediate *im,
>+						void *private_data)
>+{
>+	struct vfs_io_uring_config *config = (struct vfs_io_uring_config *)
>+						private_data;
>+
>+	vfs_io_uring_queue_run(config);
>+}
>+
> struct vfs_io_uring_pread_state {
> 	struct vfs_io_uring_request ur;
> 	struct iovec iov;
>+	/* We have to remember the original values in case of short read. */
>+	struct files_struct *fsp;
>+	void *data;
>+	size_t count;
>+	ssize_t total_read;
>+	off_t offset;
> };
> 
> static struct tevent_req *vfs_io_uring_pread_send(struct vfs_handle_struct *handle,
>@@ -319,6 +419,11 @@ static struct tevent_req *vfs_io_uring_pread_send(struct vfs_handle_struct *hand
> 	state->ur.config = config;
> 	state->ur.req = req;
> 	state->ur.state = state;
>+	state->ur.opcode = VFS_IO_URING_PREAD;
>+	state->fsp = fsp;
>+	state->data = data;
>+	state->count = n;
>+	state->offset = offset;
> 
> 	SMBPROFILE_BYTES_ASYNC_START(syscall_asys_pread, profile_p,
> 				     state->ur.profile_bytes, n);
>@@ -326,6 +431,15 @@ static struct tevent_req *vfs_io_uring_pread_send(struct vfs_handle_struct *hand
> 
> 	state->iov.iov_base = (void *)data;
> 	state->iov.iov_len = n;
>+
>+#if 0
>+/* JRATEST */
>+	if (n > 4096) {
>+		state->iov.iov_len -= 4096;
>+	}
>+/* JRATEST */
>+#endif
>+
> 	io_uring_prep_readv(&state->ur.sqe,
> 			    fsp->fh->fd,
> 			    &state->iov, 1,
>@@ -364,13 +478,76 @@ static ssize_t vfs_io_uring_pread_recv(struct tevent_req *req,
> 		ret = -1;
> 	} else {
> 		vfs_aio_state->error = 0;
>-		ret = state->ur.cqe.res;
>+		ret = state->total_read;
> 	}
> 
> 	tevent_req_received(req);
> 	return ret;
> }
> 
>+/* Returns false if more to read. Updates the total_read count. */
>+
>+static bool is_io_uring_pread_complete(struct vfs_io_uring_request *cur,
>+			      const struct io_uring_cqe *cqe)
>+{
>+	struct tevent_req *req = talloc_get_type_abort(cur->req,
>+					struct tevent_req);
>+	struct vfs_io_uring_pread_state *state = tevent_req_data(
>+			req, struct vfs_io_uring_pread_state);
>+
>+	if (cqe->res < 0) {
>+		/* Error. Deal with it as normal. */
>+		return true;
>+	}
>+
>+	if (cqe->res == 0) {
>+		/* EOF. Deal with it as normal. */
>+		return true;
>+	}
>+
>+	state->total_read += cqe->res;
>+
>+	if (state->total_read < state->count ) {
>+		/* More needed. */
>+		DBG_DEBUG("short read, %p wanted %u at offset %u, got %u\n",
>+			state->iov.iov_base,
>+			(unsigned int)state->count,
>+			(unsigned int)state->offset,
>+			(unsigned int)state->total_read);
>+		return false;
>+	}
>+	return true;
>+}
>+
>+/* Short read. Adjust the buffer, length and offsets and resubmit. */
>+static void vfs_io_uring_pread_op_reschedule(struct vfs_io_uring_config *config,
>+					     struct vfs_io_uring_request *cur)
>+{
>+	struct tevent_req *req = talloc_get_type_abort(cur->req,
>+					struct tevent_req);
>+	struct vfs_io_uring_pread_state *state = tevent_req_data(
>+			req, struct vfs_io_uring_pread_state);
>+	off_t offset;
>+	uint8_t *new_base = (uint8_t *)state->data + state->total_read;
>+
>+	/* Set up the parameters for the remaining IO. */
>+	state->iov.iov_base = (void *)new_base;
>+	state->iov.iov_len = state->count - state->total_read;
>+	offset = state->offset + state->total_read;
>+
>+	DBG_DEBUG("reschedule, %p get %u, at offset %u\n",
>+			state->iov.iov_base,
>+			(unsigned int)state->iov.iov_len,
>+			(unsigned int)offset);
>+
>+	io_uring_prep_readv(&cur->sqe,
>+			    state->fsp->fh->fd,
>+			    &state->iov,
>+			    1,
>+			    offset);
>+	io_uring_sqe_set_data(&cur->sqe, cur);
>+}
>+
> struct vfs_io_uring_pwrite_state {
> 	struct vfs_io_uring_request ur;
> 	struct iovec iov;
>@@ -399,6 +576,7 @@ static struct tevent_req *vfs_io_uring_pwrite_send(struct vfs_handle_struct *han
> 	state->ur.config = config;
> 	state->ur.req = req;
> 	state->ur.state = state;
>+	state->ur.opcode = VFS_IO_URING_PWRITE;
> 
> 	SMBPROFILE_BYTES_ASYNC_START(syscall_asys_pwrite, profile_p,
> 				     state->ur.profile_bytes, n);
>@@ -476,6 +654,7 @@ static struct tevent_req *vfs_io_uring_fsync_send(struct vfs_handle_struct *hand
> 	state->ur.config = config;
> 	state->ur.req = req;
> 	state->ur.state = state;
>+	state->ur.opcode = VFS_IO_URING_FSYNC;
> 
> 	SMBPROFILE_BYTES_ASYNC_START(syscall_asys_fsync, profile_p,
> 				     state->ur.profile_bytes, 0);
>-- 
>2.20.1
>

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Attachments on bug 14361: 15947 | 15955 | 15960 | 15961 | 15962 | 15964 | 15965 | 15969 | 15971 | 15976