From 5febf432df1cfa5b25d99b54c32103fafbdd0eb9 Mon Sep 17 00:00:00 2001 From: Miguel Ojeda Date: Sun, 16 Aug 2026 15:32:33 +0200 Subject: kbuild: rust: keep Rust objects out of Clang LTO with inline helpers Under `CONFIG_LTO_CLANG` + `CONFIG_RUST_INLINE_HELPERS`, one may hit `objtool` errors such as: vmlinux.o: error: objtool: _R..._3Gsp4boot+0xd6a: can't find jump dest instruction at .text._R..._3Gsp4boot+0x1dfd The reason is that in such builds, the Clang invocation that compiles the combined Rust plus helpers bitcode emits LLVM bitcode (again) -- the final code generation happens in the linker's LTO step, which the `-mllvm` trap options passed to Clang do not reach. This, in turn, means that unreachable traps are missing, and the impossible paths do not merely fallthrough to the next symbol, but past the end of their own section, since LTO builds place each function in its own section. Thus filter `CC_FLAGS_LTO` out of the Clang invocation, so that it always emits machine code directly, with the traps in place. Assisted-by: LLM Cc: Gary Guo Cc: Boqun Feng Cc: Alice Ryhl Cc: Matthew Maurer Cc: Josh Poimboeuf Cc: Peter Zijlstra Cc: stable@vger.kernel.org Fixes: 3a2486cc1da5 ("kbuild: rust: provide an option to inline C helpers into Rust") Acked-by: Gary Guo Link: https://patch.msgid.link/20260816133233.197500-2-ojeda@kernel.org Signed-off-by: Miguel Ojeda --- fs/orangefs/waitqueue.c | 373 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 373 insertions(+) create mode 100644 fs/orangefs/waitqueue.c (limited to 'fs/orangefs/waitqueue.c') diff --git a/fs/orangefs/waitqueue.c b/fs/orangefs/waitqueue.c new file mode 100644 index 000000000..beafc33d5 --- /dev/null +++ b/fs/orangefs/waitqueue.c @@ -0,0 +1,373 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * (C) 2001 Clemson University and The University of Chicago + * (C) 2011 Omnibond Systems + * + * Changes by Acxiom Corporation to implement generic service_operation() + * function, Copyright Acxiom Corporation, 2005. + * + * See COPYING in top-level directory. + */ + +/* + * In-kernel waitqueue operations. + */ + +#include "protocol.h" +#include "orangefs-kernel.h" +#include "orangefs-bufmap.h" + +static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op, + long timeout, + int flags) + __acquires(op->lock); +static void orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op) + __releases(op->lock); + +/* + * What we do in this function is to walk the list of operations that are + * present in the request queue and mark them as purged. + * NOTE: This is called from the device close after client-core has + * guaranteed that no new operations could appear on the list since the + * client-core is anyway going to exit. + */ +void purge_waiting_ops(void) +{ + struct orangefs_kernel_op_s *op, *tmp; + + spin_lock(&orangefs_request_list_lock); + list_for_each_entry_safe(op, tmp, &orangefs_request_list, list) { + gossip_debug(GOSSIP_WAIT_DEBUG, + "pvfs2-client-core: purging op tag %llu %s\n", + llu(op->tag), + get_opname_string(op)); + set_op_state_purged(op); + gossip_debug(GOSSIP_DEV_DEBUG, + "%s: op:%s: op_state:%d: process:%s:\n", + __func__, + get_opname_string(op), + op->op_state, + current->comm); + } + spin_unlock(&orangefs_request_list_lock); +} + +/* + * submits a ORANGEFS operation and waits for it to complete + * + * Note op->downcall.status will contain the status of the operation (in + * errno format), whether provided by pvfs2-client or a result of failure to + * service the operation. If the caller wishes to distinguish, then + * op->state can be checked to see if it was serviced or not. + * + * Returns contents of op->downcall.status for convenience + */ +int service_operation(struct orangefs_kernel_op_s *op, + const char *op_name, + int flags) +{ + long timeout = MAX_SCHEDULE_TIMEOUT; + int ret = 0; + + DEFINE_WAIT(wait_entry); + + op->upcall.tgid = current->tgid; + op->upcall.pid = current->pid; + +retry_servicing: + op->downcall.status = 0; + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: %s op:%p: process:%s: pid:%d:\n", + __func__, + op_name, + op, + current->comm, + current->pid); + + /* + * If ORANGEFS_OP_NO_MUTEX was set in flags, we need to avoid + * acquiring the request_mutex because we're servicing a + * high priority remount operation and the request_mutex is + * already taken. + */ + if (!(flags & ORANGEFS_OP_NO_MUTEX)) { + if (flags & ORANGEFS_OP_INTERRUPTIBLE) + ret = mutex_lock_interruptible(&orangefs_request_mutex); + else + ret = mutex_lock_killable(&orangefs_request_mutex); + /* + * check to see if we were interrupted while waiting for + * mutex + */ + if (ret < 0) { + op->downcall.status = ret; + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: service_operation interrupted.\n", + __func__); + return ret; + } + } + + /* queue up the operation */ + spin_lock(&orangefs_request_list_lock); + spin_lock(&op->lock); + set_op_state_waiting(op); + gossip_debug(GOSSIP_DEV_DEBUG, + "%s: op:%s: op_state:%d: process:%s:\n", + __func__, + get_opname_string(op), + op->op_state, + current->comm); + /* add high priority remount op to the front of the line. */ + if (flags & ORANGEFS_OP_PRIORITY) + list_add(&op->list, &orangefs_request_list); + else + list_add_tail(&op->list, &orangefs_request_list); + spin_unlock(&op->lock); + wake_up_interruptible(&orangefs_request_list_waitq); + if (!__is_daemon_in_service()) { + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s:client core is NOT in service.\n", + __func__); + /* + * Don't wait for the userspace component to return if + * the filesystem is being umounted anyway. + */ + if (op->upcall.type == ORANGEFS_VFS_OP_FS_UMOUNT) + timeout = 0; + else + timeout = op_timeout_secs * HZ; + } + spin_unlock(&orangefs_request_list_lock); + + if (!(flags & ORANGEFS_OP_NO_MUTEX)) + mutex_unlock(&orangefs_request_mutex); + + ret = wait_for_matching_downcall(op, timeout, flags); + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: wait_for_matching_downcall returned %d for %p\n", + __func__, + ret, + op); + + /* got matching downcall; make sure status is in errno format */ + if (!ret) { + spin_unlock(&op->lock); + op->downcall.status = + orangefs_normalize_to_errno(op->downcall.status); + ret = op->downcall.status; + goto out; + } + + /* failed to get matching downcall */ + if (ret == -ETIMEDOUT) { + gossip_err("%s: %s -- wait timed out; aborting attempt.\n", + __func__, + op_name); + } + + /* + * remove a waiting op from the request list or + * remove an in-progress op from the in-progress list. + */ + orangefs_clean_up_interrupted_operation(op); + + op->downcall.status = ret; + /* retry if operation has not been serviced and if requested */ + if (ret == -EAGAIN) { + op->attempts++; + timeout = op_timeout_secs * HZ; + gossip_debug(GOSSIP_WAIT_DEBUG, + "orangefs: tag %llu (%s)" + " -- operation to be retried (%d attempt)\n", + llu(op->tag), + op_name, + op->attempts); + + /* + * io ops (ops that use the shared memory buffer) have + * to be returned to their caller for a retry. Other ops + * can just be recycled here. + */ + if (!op->uses_shared_memory) + goto retry_servicing; + } + +out: + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: %s returning: %d for %p.\n", + __func__, + op_name, + ret, + op); + return ret; +} + +/* This can get called on an I/O op if it had a bad service_operation. */ +bool orangefs_cancel_op_in_progress(struct orangefs_kernel_op_s *op) +{ + u64 tag = op->tag; + if (!op_state_in_progress(op)) + return false; + + op->slot_to_free = op->upcall.req.io.buf_index; + memset(&op->upcall, 0, sizeof(op->upcall)); + memset(&op->downcall, 0, sizeof(op->downcall)); + op->upcall.type = ORANGEFS_VFS_OP_CANCEL; + op->upcall.req.cancel.op_tag = tag; + op->downcall.type = ORANGEFS_VFS_OP_INVALID; + op->downcall.status = -1; + orangefs_new_tag(op); + + spin_lock(&orangefs_request_list_lock); + /* orangefs_request_list_lock is enough of a barrier here */ + if (!__is_daemon_in_service()) { + spin_unlock(&orangefs_request_list_lock); + return false; + } + spin_lock(&op->lock); + set_op_state_waiting(op); + gossip_debug(GOSSIP_DEV_DEBUG, + "%s: op:%s: op_state:%d: process:%s:\n", + __func__, + get_opname_string(op), + op->op_state, + current->comm); + list_add(&op->list, &orangefs_request_list); + spin_unlock(&op->lock); + spin_unlock(&orangefs_request_list_lock); + + gossip_debug(GOSSIP_WAIT_DEBUG, + "Attempting ORANGEFS operation cancellation of tag %llu\n", + llu(tag)); + return true; +} + +/* + * Change an op to the "given up" state and remove it from its list. + */ +static void + orangefs_clean_up_interrupted_operation(struct orangefs_kernel_op_s *op) + __releases(op->lock) +{ + /* + * handle interrupted cases depending on what state we were in when + * the interruption is detected. + * + * Called with op->lock held. + */ + + /* + * List manipulation code elsewhere will ignore ops that + * have been given up upon. + */ + op->op_state |= OP_VFS_STATE_GIVEN_UP; + + if (list_empty(&op->list)) { + /* caught copying to/from daemon */ + BUG_ON(op_state_serviced(op)); + spin_unlock(&op->lock); + wait_for_completion(&op->waitq); + } else if (op_state_waiting(op)) { + /* + * upcall hasn't been read; remove op from upcall request + * list. + */ + spin_unlock(&op->lock); + spin_lock(&orangefs_request_list_lock); + list_del_init(&op->list); + spin_unlock(&orangefs_request_list_lock); + gossip_debug(GOSSIP_WAIT_DEBUG, + "Interrupted: Removed op %p from request_list\n", + op); + } else if (op_state_in_progress(op)) { + /* op must be removed from the in progress htable */ + spin_unlock(&op->lock); + spin_lock(&orangefs_htable_ops_in_progress_lock); + list_del_init(&op->list); + spin_unlock(&orangefs_htable_ops_in_progress_lock); + gossip_debug(GOSSIP_WAIT_DEBUG, + "Interrupted: Removed op %p" + " from htable_ops_in_progress\n", + op); + } else { + spin_unlock(&op->lock); + gossip_err("interrupted operation is in a weird state 0x%x\n", + op->op_state); + } + reinit_completion(&op->waitq); +} + +/* + * Sleeps on waitqueue waiting for matching downcall. + * If client-core finishes servicing, then we are good to go. + * else if client-core exits, we get woken up here, and retry with a timeout + * + * When this call returns to the caller, the specified op will no + * longer be in either the in_progress hash table or on the request list. + * + * Returns 0 on success and -errno on failure + * Errors are: + * EAGAIN in case we want the caller to requeue and try again.. + * EINTR/EIO/ETIMEDOUT indicating we are done trying to service this + * operation since client-core seems to be exiting too often + * or if we were interrupted. + * + * Returns with op->lock taken. + */ +static int wait_for_matching_downcall(struct orangefs_kernel_op_s *op, + long timeout, + int flags) + __acquires(op->lock) +{ + long n; + int writeback = flags & ORANGEFS_OP_WRITEBACK, + interruptible = flags & ORANGEFS_OP_INTERRUPTIBLE; + + /* + * There's a "schedule_timeout" inside of these wait + * primitives, during which the op is out of the hands of the + * user process that needs something done and is being + * manipulated by the client-core process. + */ + if (writeback) + n = wait_for_completion_io_timeout(&op->waitq, timeout); + else if (!writeback && interruptible) + n = wait_for_completion_interruptible_timeout(&op->waitq, + timeout); + else /* !writeback && !interruptible but compiler complains */ + n = wait_for_completion_killable_timeout(&op->waitq, timeout); + + spin_lock(&op->lock); + + if (op_state_serviced(op)) + return 0; + + if (unlikely(n < 0)) { + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: operation interrupted, tag %llu, %p\n", + __func__, + llu(op->tag), + op); + return -EINTR; + } + if (op_state_purged(op)) { + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: operation purged, tag %llu, %p, %d\n", + __func__, + llu(op->tag), + op, + op->attempts); + return (op->attempts < ORANGEFS_PURGE_RETRY_COUNT) ? + -EAGAIN : + -EIO; + } + /* must have timed out, then... */ + gossip_debug(GOSSIP_WAIT_DEBUG, + "%s: operation timed out, tag %llu, %p, %d)\n", + __func__, + llu(op->tag), + op, + op->attempts); + return -ETIMEDOUT; +} -- cgit v1.3.1