The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=d37286b9bf92ec923ab6823bbedef9e39e7e1ebb
commit d37286b9bf92ec923ab6823bbedef9e39e7e1ebb Author: Mark Johnston <[email protected]> AuthorDate: 2024-07-29 01:41:06 +0000 Commit: Mark Johnston <[email protected]> CommitDate: 2024-07-29 01:43:49 +0000 proc: Remove kernel stack swapping support, part 7 Remove some uses of PHOLD which were there only to prevent the process' threads from being swapped out. Tested by: pho Reviewed by: imp, kib Differential Revision: https://reviews.freebsd.org/D46118 --- sys/cam/cam_periph.c | 14 -------------- sys/compat/linuxkpi/common/src/linux_schedule.c | 6 ------ sys/dev/nvme/nvme_ctrlr.c | 12 ------------ sys/kern/kern_physio.c | 7 ------- sys/kern/kern_procctl.c | 10 ---------- sys/kern/subr_firmware.c | 2 -- sys/ufs/ffs/ffs_rawread.c | 6 ------ sys/ufs/ffs/ffs_softdep.c | 4 ---- 8 files changed, 61 deletions(-) diff --git a/sys/cam/cam_periph.c b/sys/cam/cam_periph.c index e957edee67f1..4052ec2e1570 100644 --- a/sys/cam/cam_periph.c +++ b/sys/cam/cam_periph.c @@ -928,16 +928,6 @@ cam_periph_mapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo, } } - /* - * This keeps the kernel stack of current thread from getting - * swapped. In low-memory situations where the kernel stack might - * otherwise get swapped out, this holds it and allows the thread - * to make progress and release the kernel mapped pages sooner. - * - * XXX KDM should I use P_NOSWAP instead? - */ - PHOLD(curproc); - for (i = 0; i < numbufs; i++) { /* Save the user's data address. */ mapinfo->orig[i] = *data_ptrs[i]; @@ -1005,7 +995,6 @@ fail: free(*data_ptrs[i], M_CAMPERIPH); *data_ptrs[i] = mapinfo->orig[i]; } - PRELE(curproc); return(EACCES); } @@ -1116,9 +1105,6 @@ cam_periph_unmapmem(union ccb *ccb, struct cam_periph_map_info *mapinfo) *data_ptrs[i] = mapinfo->orig[i]; } - /* allow ourselves to be swapped once again */ - PRELE(curproc); - return (error); } diff --git a/sys/compat/linuxkpi/common/src/linux_schedule.c b/sys/compat/linuxkpi/common/src/linux_schedule.c index 66b339bfbdbd..3349a4aa8d72 100644 --- a/sys/compat/linuxkpi/common/src/linux_schedule.c +++ b/sys/compat/linuxkpi/common/src/linux_schedule.c @@ -268,11 +268,6 @@ linux_wait_event_common(wait_queue_head_t *wqh, wait_queue_t *wq, int timeout, task = current; - /* - * Our wait queue entry is on the stack - make sure it doesn't - * get swapped out while we sleep. - */ - PHOLD(task->task_thread->td_proc); sleepq_lock(task); if (atomic_read(&task->state) != TASK_WAKING) { ret = linux_add_to_sleepqueue(task, task, "wevent", timeout, @@ -281,7 +276,6 @@ linux_wait_event_common(wait_queue_head_t *wqh, wait_queue_t *wq, int timeout, sleepq_release(task); ret = 0; } - PRELE(task->task_thread->td_proc); if (lock != NULL) spin_lock_irq(lock); diff --git a/sys/dev/nvme/nvme_ctrlr.c b/sys/dev/nvme/nvme_ctrlr.c index e07ac737ffc8..52834cb26b8e 100644 --- a/sys/dev/nvme/nvme_ctrlr.c +++ b/sys/dev/nvme/nvme_ctrlr.c @@ -1259,11 +1259,6 @@ nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr, return EIO; } if (is_user_buffer) { - /* - * Ensure the user buffer is wired for the duration of - * this pass-through command. - */ - PHOLD(curproc); buf = uma_zalloc(pbuf_zone, M_WAITOK); buf->b_iocmd = pt->is_read ? BIO_READ : BIO_WRITE; if (vmapbuf(buf, pt->buf, pt->len, 1) < 0) { @@ -1309,7 +1304,6 @@ nvme_ctrlr_passthrough_cmd(struct nvme_controller *ctrlr, vunmapbuf(buf); err: uma_zfree(pbuf_zone, buf); - PRELE(curproc); } return (ret); @@ -1356,11 +1350,6 @@ nvme_ctrlr_linux_passthru_cmd(struct nvme_controller *ctrlr, if ((npc->opcode & 0x3) == 0 || (npc->opcode & 0x3) == 3) return (EINVAL); if (is_user) { - /* - * Ensure the user buffer is wired for the duration of - * this pass-through command. - */ - PHOLD(curproc); buf = uma_zalloc(pbuf_zone, M_WAITOK); buf->b_iocmd = npc->opcode & 1 ? BIO_WRITE : BIO_READ; if (vmapbuf(buf, (void *)(uintptr_t)npc->addr, @@ -1408,7 +1397,6 @@ nvme_ctrlr_linux_passthru_cmd(struct nvme_controller *ctrlr, vunmapbuf(buf); err: uma_zfree(pbuf_zone, buf); - PRELE(curproc); } return (ret); diff --git a/sys/kern/kern_physio.c b/sys/kern/kern_physio.c index 79b7694192e4..787505c1096f 100644 --- a/sys/kern/kern_physio.c +++ b/sys/kern/kern_physio.c @@ -87,12 +87,6 @@ physio(struct cdev *dev, struct uio *uio, int ioflag) return (EFBIG); } - /* - * Keep the process UPAGES from being swapped. Processes swapped - * out while holding pbufs, used by swapper, may lead to deadlock. - */ - PHOLD(curproc); - bp = g_alloc_bio(); if (uio->uio_segflg != UIO_USERSPACE) { pbuf = NULL; @@ -209,6 +203,5 @@ doerror: else if (pages) free(pages, M_DEVBUF); g_destroy_bio(bp); - PRELE(curproc); return (error); } diff --git a/sys/kern/kern_procctl.c b/sys/kern/kern_procctl.c index 888feb94bb8d..e7519f1b0de4 100644 --- a/sys/kern/kern_procctl.c +++ b/sys/kern/kern_procctl.c @@ -573,17 +573,7 @@ reap_kill(struct thread *td, struct proc *p, void *data) w.rk = rk; w.error = &error; TASK_INIT(&w.t, 0, reap_kill_proc_work, &w); - - /* - * Prevent swapout, since w, ksi, and possibly rk, are - * allocated on the stack. We sleep in - * reap_kill_subtree_once() waiting for task to - * complete single-threading. - */ - PHOLD(td->td_proc); - reap_kill_subtree(td, p, reaper, &w); - PRELE(td->td_proc); crfree(w.cr); } PROC_LOCK(p); diff --git a/sys/kern/subr_firmware.c b/sys/kern/subr_firmware.c index 99f7ef6ff8b9..d616339f2c07 100644 --- a/sys/kern/subr_firmware.c +++ b/sys/kern/subr_firmware.c @@ -419,9 +419,7 @@ firmware_get_flags(const char *imagename, uint32_t flags) fwli.flags = flags; TASK_INIT(&fwload_task, 0, loadimage, (void *)&fwli); taskqueue_enqueue(firmware_tq, &fwload_task); - PHOLD(curproc); msleep((void *)&fwli, &firmware_mtx, 0, "fwload", 0); - PRELE(curproc); } /* * After attempting to load the module, see if the image is registered. diff --git a/sys/ufs/ffs/ffs_rawread.c b/sys/ufs/ffs/ffs_rawread.c index 3a415d766303..9db0bee0d66d 100644 --- a/sys/ufs/ffs/ffs_rawread.c +++ b/sys/ufs/ffs/ffs_rawread.c @@ -265,11 +265,6 @@ ffs_rawread_main(struct vnode *vp, resid = uio->uio_resid; offset = uio->uio_offset; - /* - * keep the process from being swapped - */ - PHOLD(td->td_proc); - error = 0; nerror = 0; @@ -389,7 +384,6 @@ ffs_rawread_main(struct vnode *vp, if (error == 0) error = nerror; - PRELE(td->td_proc); uio->uio_iov->iov_base = udata; uio->uio_resid = resid; uio->uio_offset = offset; diff --git a/sys/ufs/ffs/ffs_softdep.c b/sys/ufs/ffs/ffs_softdep.c index 5c8e2b6cde81..86c90000e8d2 100644 --- a/sys/ufs/ffs/ffs_softdep.c +++ b/sys/ufs/ffs/ffs_softdep.c @@ -1904,7 +1904,6 @@ process_worklist_item(struct mount *mp, */ if (curthread->td_pflags & TDP_COWINPROGRESS) return (-1); - PHOLD(curproc); /* Don't let the stack go away. */ ump = VFSTOUFS(mp); LOCK_OWNED(ump); matchcnt = 0; @@ -1977,7 +1976,6 @@ process_worklist_item(struct mount *mp, ump->softdep_worklist_tail = (struct worklist *)sentinel.wk_list.le_prev; LIST_REMOVE(&sentinel, wk_list); - PRELE(curproc); return (matchcnt); } @@ -10230,7 +10228,6 @@ softdep_disk_io_initiation( return; marker.wk_type = D_LAST + 1; /* Not a normal workitem */ - PHOLD(curproc); /* Don't swap out kernel stack */ ACQUIRE_LOCK(ump); /* * Do any necessary pre-I/O processing. @@ -10315,7 +10312,6 @@ softdep_disk_io_initiation( } } FREE_LOCK(ump); - PRELE(curproc); /* Allow swapout of kernel stack */ } /*
