The branch main has been updated by dumbbell: URL: https://cgit.FreeBSD.org/src/commit/?id=28d6ffe37cf928c5b13e0aa34c39c4414a0f09e4
commit 28d6ffe37cf928c5b13e0aa34c39c4414a0f09e4 Author: Jean-Sébastien Pédron <[email protected]> AuthorDate: 2025-05-26 17:36:49 +0000 Commit: Jean-Sébastien Pédron <[email protected]> CommitDate: 2026-01-25 16:04:44 +0000 eventfd: Add eventfd_signal() The `eventfd_signal()` function is the equivalent to a write to an eventfd file descriptor: it bumps the internal counter and wakes up processes waiting for it. `eventfd_signal()` is meant to be used by kernel drivers. DRM drivers will call it through linuxkpi. Reviewed by: markj Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D50850 --- sys/kern/sys_eventfd.c | 25 ++++++++++++++++++++++--- sys/sys/eventfd.h | 1 + 2 files changed, 23 insertions(+), 3 deletions(-) diff --git a/sys/kern/sys_eventfd.c b/sys/kern/sys_eventfd.c index 433bcb57b2b3..47f1fcc316ec 100644 --- a/sys/kern/sys_eventfd.c +++ b/sys/kern/sys_eventfd.c @@ -157,6 +157,27 @@ eventfd_put(struct eventfd *efd) free(efd, M_EVENTFD); } +static void +eventfd_wakeup(struct eventfd *efd) +{ + KNOTE_LOCKED(&efd->efd_sel.si_note, 0); + selwakeup(&efd->efd_sel); + wakeup(&efd->efd_count); +} + +void +eventfd_signal(struct eventfd *efd) +{ + mtx_lock(&efd->efd_lock); + + if (efd->efd_count < UINT64_MAX) + efd->efd_count++; + + eventfd_wakeup(efd); + + mtx_unlock(&efd->efd_lock); +} + static int eventfd_close(struct file *fp, struct thread *td) { @@ -244,9 +265,7 @@ retry: if (error == 0) { MPASS(UINT64_MAX - efd->efd_count > count); efd->efd_count += count; - KNOTE_LOCKED(&efd->efd_sel.si_note, 0); - selwakeup(&efd->efd_sel); - wakeup(&efd->efd_count); + eventfd_wakeup(efd); } mtx_unlock(&efd->efd_lock); diff --git a/sys/sys/eventfd.h b/sys/sys/eventfd.h index 1f36dbecb92d..1b390feed48e 100644 --- a/sys/sys/eventfd.h +++ b/sys/sys/eventfd.h @@ -44,6 +44,7 @@ int eventfd_create_file(struct thread *td, struct file *fp, uint32_t initval, int flags); struct eventfd *eventfd_get(struct file *fp); void eventfd_put(struct eventfd *efd); +void eventfd_signal(struct eventfd *efd); #else
