git: 94816f650989 - stable/15 - amd64: add helpers to set up thread state on trap

The branch stable/15 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=94816f650989310f5d19dc562b73544e84520eaf

commit 94816f650989310f5d19dc562b73544e84520eaf
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2026-10-29 02:16:42 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2026-11-03 09:01:18 +0000

    amd64: add helpers to set up thread state on trap
    
    (cherry picked from commit 7f49a62e3c5ff15d87afcce9ab7fe787319a3f7f)
---
 sys/amd64/amd64/trap.c | 25 +++++++++++++++++--------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/sys/amd64/amd64/trap.c b/sys/amd64/amd64/trap.c
index 94b8804268b3..6de47c23c79a 100644
--- a/sys/amd64/amd64/trap.c
+++ b/sys/amd64/amd64/trap.c
@@ -356,6 +356,15 @@ static const struct sfhandler sfhandlers[] = {
 	},
 };
 
+static void
+trap_update_thread(struct thread *td, struct trapframe *frame)
+{
+	td->td_pticks = 0;
+	td->td_frame = frame;
+	if (td->td_cowgen != atomic_load_int(&td->td_proc->p_cowgen))
+		thread_cow_update(td);
+}
+
 /*
  * Exception, fault, and trap interface to the FreeBSD kernel.
  * This common code is called from assembly language IDT gate entry
@@ -404,11 +413,8 @@ trap(struct trapframe *frame)
 		/* user trap */
 		trap_check_intr_user(td, frame);
 
-		td->td_pticks = 0;
-		td->td_frame = frame;
+		trap_update_thread(td, frame);
 		addr = frame->tf_rip;
-		if (td->td_cowgen != atomic_load_int(&p->p_cowgen))
-			thread_cow_update(td);
 
 		switch (type) {
 		case T_PRIVINFLT:	/* privileged instruction fault */
@@ -1587,6 +1593,12 @@ trap_fred_u_noperm(struct trapframe_fred *frame, ksiginfo_t *ksi)
 	ksi->ksi_addr = (void *)frame->tf_idt.tf_rip;
 }
 
+static void
+trap_fred_update_thread(struct thread *td, struct trapframe_fred *frame)
+{
+	trap_update_thread(td, &frame->tf_idt);
+}
+
 int fred_verbose_events;
 
 void trap_fred_u(struct trapframe_fred *frame);
@@ -1650,10 +1662,7 @@ trap_fred_u(struct trapframe_fred *frame)
 		    &frame->tf_idt, frame->tf_idt.tf_trapno) != 0)
 			return;
 #endif
-		td->td_pticks = 0;
-		td->td_frame = &frame->tf_idt;
-		if (td->td_cowgen != atomic_load_int(&td->td_proc->p_cowgen))
-			thread_cow_update(td);
+		trap_fred_update_thread(td, frame);
 		trap_fred_handle_u_exc(td, frame, vec, &ksi, &do_trapsig);
 		break;
 	case TF_FRED_EVINFO2_TYPE_INTn: