From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:56288) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7vbx-0001rD-2M for qemu-devel@nongnu.org; Wed, 24 Jun 2015 21:05:50 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z7vbt-0006cU-Gy for qemu-devel@nongnu.org; Wed, 24 Jun 2015 21:05:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:48113) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7vbt-0006cK-9M for qemu-devel@nongnu.org; Wed, 24 Jun 2015 21:05:45 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (Postfix) with ESMTPS id D037FBAEDE for ; Thu, 25 Jun 2015 01:05:44 +0000 (UTC) Date: Thu, 25 Jun 2015 09:05:41 +0800 From: Fam Zheng Message-ID: <20150625010541.GD17695@ad.nay.redhat.com> References: <1435070633-20071-1-git-send-email-dgilbert@redhat.com> <20150624151951.GG7454@stefanha-thinkpad.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150624151951.GG7454@stefanha-thinkpad.redhat.com> Subject: Re: [Qemu-devel] [PATCH] gdb command: qemu iohandlers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Stefan Hajnoczi Cc: quintela@redhat.com, "Dr. David Alan Gilbert (git)" , qemu-devel@nongnu.org On Wed, 06/24 16:19, Stefan Hajnoczi wrote: > On Tue, Jun 23, 2015 at 03:43:53PM +0100, Dr. David Alan Gilbert (git) wrote: > > From: "Dr. David Alan Gilbert" > > > > Add a gdb command to print the current set of IOHandlers and > > if one of them is a thread yielding for data print the backtrace. > > > > Useful for debugging why an incoming migration has stalled, e.g. > > > > ---- > > {fd_read = 0x7fd4c8e40d00 , fd_write = 0x0, opaque = > > 0x7fd4b8bfeb00, next = {le_next = 0x7fd4cac81b00, le_prev = > > 0x7fd4c93d2bd0 }, fd = 22, pollfds_idx = 0, deleted = > > false} > > #0 qemu_coroutine_switch (from_=from_@entry=0x7fd4cbb33c00, > > to_=to_@entry=0x7fd4c8b13a90, > > action=action@entry=COROUTINE_YIELD) at coroutine-ucontext.c:177 > > #1 0x00007fd4c8e40507 in qemu_coroutine_yield () at > > qemu-coroutine.c:145 > > #2 0x00007fd4c8e40e75 in yield_until_fd_readable (fd=22) at > > qemu-coroutine-io.c:90 > > #3 0x00007fd4c8df347f in qemu_rdma_block_for_wrid > > (rdma=rdma@entry=0x7fd4b8c7e010, > > wrid_requested=wrid_requested@entry=2000, > > byte_len=byte_len@entry=0x0) at migration/rdma.c:1510 > > #4 0x00007fd4c8df388f in qemu_rdma_post_send_control > > (rdma=rdma@entry=0x7fd4b8c7e010, buf=buf@entry=0x0, > > head=head@entry=0x7fd4b8bfed00) at migration/rdma.c:1608 > > #5 0x00007fd4c8df4b8e in qemu_rdma_exchange_recv (rdma=0x7fd4b8c7e010, > > head=0x7fd4b8bfed50, expecting=3) > > at migration/rdma.c:1814 > > #6 0x00007fd4c8df5089 in qemu_rdma_get_buffer (opaque=0x7fd4cba34950, > > buf=0x7fd4cc24fd20 "TR\022", > > pos=, size=32768) at migration/rdma.c:2611 > > #7 0x00007fd4c8df000d in qemu_fill_buffer (f=f@entry=0x7fd4cc24fcf0) at > > migration/qemu-file.c:214 > > #8 0x00007fd4c8df08d4 in qemu_peek_byte (f=f@entry=0x7fd4cc24fcf0, > > offset=offset@entry=0) > > at migration/qemu-file.c:447 > > #9 0x00007fd4c8c2cad1 in qemu_loadvm_state (f=f@entry=0x7fd4cc24fcf0) > > at /root/qemu-world3/migration/savevm.c:1128 > > #10 0x00007fd4c8ded895 in process_incoming_migration_co > > (opaque=0x7fd4cc24fcf0) at migration/migration.c:145 > > #11 0x00007fd4c8e4112a in coroutine_trampoline (i0=, > > i1=) at coroutine-ucontext.c:80 > > #12 0x00007fd4c453e0f0 in ?? () from /lib64/libc.so.6 > > #13 0x00007ffee263e870 in ?? () > > #14 0x0000000000000000 in ?? () > > ---- > > {fd_read = 0x7fd4c8e3ace0 , fd_write = 0x0, opaque = 0x5, > > next = {le_next = 0x0, le_prev = 0x7fd4cb78a3d8}, fd = 5, pollfds_idx = > > 1, deleted = false} > > > > Signed-off-by: Dr. David Alan Gilbert > > --- > > scripts/qemu-gdb.py | 25 +++++++++++++++++++++++++ > > 1 file changed, 25 insertions(+) > > > > diff --git a/scripts/qemu-gdb.py b/scripts/qemu-gdb.py > > index 6c7f4fb..2670625 100644 > > --- a/scripts/qemu-gdb.py > > +++ b/scripts/qemu-gdb.py > > @@ -102,6 +102,30 @@ class CoroutineCommand(gdb.Command): > > coroutine_pointer = gdb.parse_and_eval(argv[0]).cast(gdb.lookup_type('CoroutineUContext').pointer()) > > bt_jmpbuf(coroutine_pointer['env']['__jmpbuf']) > > > > +class IOhandlersCommand(gdb.Command): > > + '''Display a backtrace for io handlers''' > > + def __init__(self): > > + gdb.Command.__init__(self, 'qemu iohandlers', gdb.COMMAND_DATA, > > + gdb.COMPLETE_NONE) > > + > > + def invoke(self, arg, from_tty): > > + cur = gdb.parse_and_eval('io_handlers.lh_first') > > Fam is getting rid of io_handlers and replacing it with an AioContext. > Yes, the series is [PATCH 0/9] slirp: iohandler: Rebase onto aio Fam