From mboxrd@z Thu Jan 1 00:00:00 1970 Subject: Re: [PATCH] cobalt/sched: dovetail: fix missed switching to OOB opportunities References: <20210309044520.28816-1-hongzhan.chen@intel.com> From: Jan Kiszka Message-ID: Date: Wed, 10 Mar 2021 17:15:16 +0100 MIME-Version: 1.0 In-Reply-To: <20210309044520.28816-1-hongzhan.chen@intel.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit List-Id: Discussions about the Xenomai project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: hongzha1 , xenomai@xenomai.org, Philippe Gerum On 09.03.21 05:45, hongzha1 via Xenomai wrote: > Ask for switching back to oob mode once ptrace core tell that > current is resuming from a stopped state, leaving space for > other runnable RT threads of the process to take over. > > Signed-off-by: hongzha1 > > diff --git a/kernel/cobalt/dovetail/kevents.c b/kernel/cobalt/dovetail/kevents.c > index 966a63ce0..a640c4d9e 100644 > --- a/kernel/cobalt/dovetail/kevents.c > +++ b/kernel/cobalt/dovetail/kevents.c > @@ -492,6 +492,8 @@ static void handle_ptrace_cont(void) > unregister_debugged_thread(curr); > > xnthread_set_localinfo(curr, XNHICCUP); > + > + dovetail_request_ucall(current); > } > > xnlock_put_irqrestore(&nklock, s); > diff --git a/kernel/cobalt/dovetail/sched.c b/kernel/cobalt/dovetail/sched.c > index de7c43b70..2bdddfeef 100644 > --- a/kernel/cobalt/dovetail/sched.c > +++ b/kernel/cobalt/dovetail/sched.c > @@ -56,9 +56,21 @@ int pipeline_leave_inband(void) > > int pipeline_leave_oob_prepare(void) > { > - dovetail_leave_oob(); > + int suspmask = XNRELAX; > + struct xnthread *curr = xnthread_current(); > > - return XNRELAX; > + dovetail_leave_oob(); > + /* > + * If current is being debugged, record that it should migrate > + * back in case it resumes in userspace. If it resumes in > + * kernel space, i.e. over a restarting syscall, the > + * associated hardening will clear XNCONTHI. > + */ > + if (xnthread_test_state(curr, XNSSTEP)) { > + xnthread_set_info(curr, XNCONTHI); > + suspmask |= XNDBGSTOP; > + } > + return suspmask; > } > > void pipeline_leave_oob_finish(void) > I've applied this to wip/dovetail, but that alone does not fix ptrace/gdb use cases yet: (gdb latency -> run) [ 52.097078] ------------[ cut here ]------------ [ 52.097079] WARNING: CPU: 2 PID: 1318 at ../kernel/irq/pipeline.c:316 inband_irq_enable+0x10/0x20 [ 52.097079] Modules linked in: 9p [ 52.097080] CPU: 2 PID: 1318 Comm: latency Not tainted 5.10.19+ #41 [ 52.097080] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 52.097080] IRQ stage: Linux [ 52.097081] RIP: 0010:inband_irq_enable+0x10/0x20 [ 52.097081] Code: 00 00 00 01 75 ee e8 cf fa ff ff 53 9d 5b c3 66 66 2e 0f 1f 84 00 00 00 00 00 80 3d 9a 38 b3 02 00 75 09 9c 58 f6 c4 02 75 02 <0f> 0b eb 8c 66 66 2e 0f 1f 84 00 00 00 00 00 90 0f 1f 44 00 00 48 [ 52.097081] RSP: 0000:ffffc90000783f20 EFLAGS: 00010046 [ 52.097082] RAX: 0000000000000046 RBX: ffffc90000783f58 RCX: 0000000000000000 [ 52.097082] RDX: ffffc90000783ef0 RSI: ffffffff8109e600 RDI: ffffffff81d4eee2 [ 52.097082] RBP: ffff888006e70000 R08: 0000000000000000 R09: 0000000000000000 [ 52.097083] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000004000 [ 52.097083] R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 [ 52.097083] FS: 00007ffff7fe6640(0000) GS:ffff88803ed00000(0000) knlGS:0000000000000000 [ 52.097084] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 52.097084] CR2: 00007ffff7243610 CR3: 00000000070c6001 CR4: 0000000000370ee0 [ 52.097084] Call Trace: [ 52.097084] noist_exc_debug+0xf7/0x180 [ 52.097085] ? asm_exc_debug+0x23/0x30 [ 52.097085] asm_exc_debug+0x2b/0x30 [ 52.097085] RIP: 0033:0x401df3 [ 52.097086] Code: 00 00 e9 b0 fb ff ff ff 25 62 44 20 00 68 44 00 00 00 e9 a0 fb ff ff ff 25 5a 44 20 00 68 45 00 00 00 e9 90 fb ff ff 31 ed 90 f9 30 01 00 48 8d 65 d8 5b 41 5c 41 5d 41 70 44 40 00 48 c7 c1 [ 52.097086] RSP: 002b:00007fffffffe1c0 EFLAGS: 00000346 [ 52.097086] RAX: 00007ffff7ffe0e0 RBX: 00007ffff7ffe0e0 RCX: 00007ffff7df23c7 [ 52.097087] RDX: 0000103e00000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 52.097087] RBP: 00007fffffffe3a0 R08: 00007ffff6e8f008 R09: 0000000000000009 [ 52.097087] R10: 00007ffff7ffd990 R11: 0000000000000206 R12: 0000000000000000 [ 52.097087] R13: 00007ffff7ffe110 R14: 00007ffff7ffe110 R15: 00007ffff7fe6640 [ 52.097088] irq event stamp: 0 [ 52.097088] hardirqs last enabled at (0): [<0000000000000000>] 0x0 [ 52.097088] hardirqs last disabled at (0): [] copy_process+0x718/0x1cd0 [ 52.097089] softirqs last enabled at (0): [] copy_process+0x718/0x1cd0 [ 52.097089] softirqs last disabled at (0): [<0000000000000000>] 0x0 [ 52.097089] ---[ end trace b07496576d3779dc ]--- Do I miss some other patch? Jan -- Siemens AG, T RDA IOT Corporate Competence Center Embedded Linux