From e33b438a8456aecf60a661ee75ac5977a7b49815 Mon Sep 17 00:00:00 2001 From: Roland McGrath Date: Fri, 5 Jul 1996 23:47:08 +0000 Subject: Fri Jul 5 12:22:51 1996 Roland McGrath * hurd/hurdsig.c (_hurd_internal_post_signal): In case of handled signal during critical section doing interruptible RPC, if _hurdsig_abort_rpcs wants to change thread state, do thread_set_state before thread_resume. If in critical section, pass 0 for SIGNO to _hurdsig_abort_rpcs so rpc is interrupted regardless of SA_RESTART. --- hurd/hurdsig.c | 28 +++++++++++++++++++++++++--- 1 file changed, 25 insertions(+), 3 deletions(-) (limited to 'hurd') diff --git a/hurd/hurdsig.c b/hurd/hurdsig.c index a3ec24e..1da3fa5 100644 --- a/hurd/hurdsig.c +++ b/hurd/hurdsig.c @@ -802,19 +802,41 @@ _hurd_internal_post_signal (struct hurd_sigstate *ss, } else { + int crit = __spin_lock_locked (&ss->critical_section_lock); + wait_for_reply - = (_hurdsig_abort_rpcs (ss, signo, 1, + = (_hurdsig_abort_rpcs (ss, + /* In a critical section, any RPC + should be cancelled instead of + restarted, regardless of + SA_RESTART, so the the entire + "atomic" operation can be aborted + as a unit. */ + crit ? 0 : signo, 1, &thread_state, &state_changed, &reply) != MACH_PORT_NULL); - if (__spin_lock_locked (&ss->critical_section_lock)) + if (crit) { /* The thread is in a critical section. Mark the signal as pending. When it finishes the critical section, it will check for pending signals. */ mark_pending (); - assert (! state_changed); + if (state_changed) + /* Some cases of interrupting an RPC must change the + thread state to back out the call. Normally this + change is rolled into the warping to the handler and + sigreturn, but we are not running the handler now + because the thread is in a critical section. Instead, + mutate the thread right away for the RPC interruption + and resume it; the RPC will return early so the + critical section can end soon. */ + __thread_set_state (ss->thread, MACHINE_THREAD_STATE_FLAVOR, + (natural_t *) &thread_state.basic, + MACHINE_THREAD_STATE_COUNT); + /* */ + ss->intr_port = MACH_PORT_NULL; __thread_resume (ss->thread); break; } -- cgit v1.1