Date: Thu, 7 Aug 2008 21:28:03 GMT From: Ed Schouten <ed@FreeBSD.org> To: Perforce Change Reviews <perforce@FreeBSD.org> Subject: PERFORCE change 146870 for review Message-ID: <200808072128.m77LS356025334@repoman.freebsd.org>
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http://perforce.freebsd.org/chv.cgi?CH=146870 Change 146870 by ed@ed_dull on 2008/08/07 21:27:50 Now that our condvar(9) supports Giant as its interlock, remove the evil hacks I had to make to the TTY code. We can now live without them. Affected files ... .. //depot/projects/mpsafetty/sys/kern/tty.c#17 edit Differences ... ==== //depot/projects/mpsafetty/sys/kern/tty.c#17 (text+ko) ==== @@ -880,8 +880,12 @@ STAILQ_INIT(&tp->t_outq.to_list); /* Allow drivers to use a custom mutex to lock the TTY */ - mtx_init(&tp->t_mtxobj, "tty lock", NULL, MTX_DEF); - tp->t_mtx = mutex != NULL ? mutex : &tp->t_mtxobj; + if (mutex != NULL) { + tp->t_mtx = mutex; + } else { + tp->t_mtx = &tp->t_mtxobj; + mtx_init(&tp->t_mtxobj, "tty lock", NULL, MTX_DEF); + } knlist_init(&tp->t_inpoll.si_note, tp->t_mtx, NULL, NULL, NULL); knlist_init(&tp->t_outpoll.si_note, tp->t_mtx, NULL, NULL, NULL); @@ -912,7 +916,8 @@ cv_destroy(&tp->t_bgwait); cv_destroy(&tp->t_dcdwait); - mtx_destroy(&tp->t_mtxobj); + if (tp->t_mtx == &tp->t_mtxobj) + mtx_destroy(&tp->t_mtxobj); ttydevsw_free(tp); free(tp, M_TTY); } @@ -1189,18 +1194,7 @@ #endif tty_lock_assert(tp, MA_OWNED); - if (tp->t_mtx == &Giant) { - /* - * XXX: condvar(9) doesn't allow Giant to be passed as - * its mutex. Because we don't use the per-TTY mutex - * here, temporarily abuse it to make condvar(9) work. - */ - mtx_lock(&tp->t_mtxobj); - error = cv_wait_sig(cv, &tp->t_mtxobj); - mtx_unlock(&tp->t_mtxobj); - } else { - error = cv_wait_sig(cv, tp->t_mtx); - } + error = cv_wait_sig(cv, tp->t_mtx); /* Restart the system call when we may have been revoked */ if (tp->t_revokecnt != revokecnt) @@ -1225,18 +1219,7 @@ #endif tty_lock_assert(tp, MA_OWNED); - if (tp->t_mtx == &Giant) { - /* - * XXX: condvar(9) doesn't allow Giant to be passed as - * its mutex. Because we don't use the per-TTY mutex - * here, temporarily abuse it to make condvar(9) work. - */ - mtx_lock(&tp->t_mtxobj); - error = cv_timedwait_sig(cv, &tp->t_mtxobj, hz); - mtx_unlock(&tp->t_mtxobj); - } else { - error = cv_timedwait_sig(cv, tp->t_mtx, hz); - } + error = cv_timedwait_sig(cv, tp->t_mtx, hz); /* Restart the system call when we may have been revoked */ if (tp->t_revokecnt != revokecnt)
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