single_thread_clear() w/o KERNEL_LOCK()
single_thread_clear() manipulates the same data structures as single_thread_set() and, as such, doesn't need the KERNEL_LOCK(). However cursig() does need some sort of serialization to ensure that per-process data structures like signals, flags and traced-signum stay consistent. So the diff below move the assertion up in preparation for more mp work. ok? Index: kern/kern_sig.c === RCS file: /cvs/src/sys/kern/kern_sig.c,v retrieving revision 1.274 diff -u -p -r1.274 kern_sig.c --- kern/kern_sig.c 4 Mar 2021 09:02:37 - 1.274 +++ kern/kern_sig.c 4 Mar 2021 09:35:47 - @@ -1182,6 +1182,8 @@ cursig(struct proc *p) int dolock = (p->p_flag & P_SINTR) == 0; int s; + KERNEL_ASSERT_LOCKED(); + sigpending = (p->p_siglist | pr->ps_siglist); if (sigpending == 0) return 0; @@ -1225,11 +1227,7 @@ cursig(struct proc *p) if (dolock) SCHED_UNLOCK(s); - if (dolock) - KERNEL_LOCK(); single_thread_clear(p, 0); - if (dolock) - KERNEL_UNLOCK(); /* * If we are no longer being traced, or the parent @@ -2128,7 +2126,6 @@ single_thread_clear(struct proc *p, int KASSERT(pr->ps_single == p); KASSERT(curproc == p); - KERNEL_ASSERT_LOCKED(); SCHED_LOCK(s); pr->ps_single = NULL;
Re: single_thread_clear() w/o KERNEL_LOCK()
On 04/03/21(Thu) 10:44, Martin Pieuchot wrote: > single_thread_clear() manipulates the same data structures as > single_thread_set() and, as such, doesn't need the KERNEL_LOCK(). > > However cursig() does need some sort of serialization to ensure that > per-process data structures like signals, flags and traced-signum stay > consistent. So the diff below move the assertion up in preparation for > more mp work. > > ok? Anyone? > Index: kern/kern_sig.c > === > RCS file: /cvs/src/sys/kern/kern_sig.c,v > retrieving revision 1.274 > diff -u -p -r1.274 kern_sig.c > --- kern/kern_sig.c 4 Mar 2021 09:02:37 - 1.274 > +++ kern/kern_sig.c 4 Mar 2021 09:35:47 - > @@ -1182,6 +1182,8 @@ cursig(struct proc *p) > int dolock = (p->p_flag & P_SINTR) == 0; > int s; > > + KERNEL_ASSERT_LOCKED(); > + > sigpending = (p->p_siglist | pr->ps_siglist); > if (sigpending == 0) > return 0; > @@ -1225,11 +1227,7 @@ cursig(struct proc *p) > if (dolock) > SCHED_UNLOCK(s); > > - if (dolock) > - KERNEL_LOCK(); > single_thread_clear(p, 0); > - if (dolock) > - KERNEL_UNLOCK(); > > /* >* If we are no longer being traced, or the parent > @@ -2128,7 +2126,6 @@ single_thread_clear(struct proc *p, int > > KASSERT(pr->ps_single == p); > KASSERT(curproc == p); > - KERNEL_ASSERT_LOCKED(); > > SCHED_LOCK(s); > pr->ps_single = NULL; >
Re: single_thread_clear() w/o KERNEL_LOCK()
On Mon, Mar 08, 2021 at 11:07:01AM +0100, Martin Pieuchot wrote: > On 04/03/21(Thu) 10:44, Martin Pieuchot wrote: > > single_thread_clear() manipulates the same data structures as > > single_thread_set() and, as such, doesn't need the KERNEL_LOCK(). > > > > However cursig() does need some sort of serialization to ensure that > > per-process data structures like signals, flags and traced-signum stay > > consistent. So the diff below move the assertion up in preparation for > > more mp work. > > > > ok? > > Anyone? OK claudio > > Index: kern/kern_sig.c > > === > > RCS file: /cvs/src/sys/kern/kern_sig.c,v > > retrieving revision 1.274 > > diff -u -p -r1.274 kern_sig.c > > --- kern/kern_sig.c 4 Mar 2021 09:02:37 - 1.274 > > +++ kern/kern_sig.c 4 Mar 2021 09:35:47 - > > @@ -1182,6 +1182,8 @@ cursig(struct proc *p) > > int dolock = (p->p_flag & P_SINTR) == 0; > > int s; > > > > + KERNEL_ASSERT_LOCKED(); > > + > > sigpending = (p->p_siglist | pr->ps_siglist); > > if (sigpending == 0) > > return 0; > > @@ -1225,11 +1227,7 @@ cursig(struct proc *p) > > if (dolock) > > SCHED_UNLOCK(s); > > > > - if (dolock) > > - KERNEL_LOCK(); > > single_thread_clear(p, 0); > > - if (dolock) > > - KERNEL_UNLOCK(); > > > > /* > > * If we are no longer being traced, or the parent > > @@ -2128,7 +2126,6 @@ single_thread_clear(struct proc *p, int > > > > KASSERT(pr->ps_single == p); > > KASSERT(curproc == p); > > - KERNEL_ASSERT_LOCKED(); > > > > SCHED_LOCK(s); > > pr->ps_single = NULL; > > > -- :wq Claudio
