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From: Kevin Wolf <kwolf@redhat.com>
To: qemu-block@nongnu.org
Cc: kwolf@redhat.com, qemu-devel@nongnu.org
Subject: [Qemu-devel] [PULL 11/14] block: Don't acquire AioContext in hmp_qemu_io()
Date: Wed, 20 Dec 2017 14:19:36 +0100	[thread overview]
Message-ID: <20171220131939.27543-12-kwolf@redhat.com> (raw)
In-Reply-To: <20171220131939.27543-1-kwolf@redhat.com>

Commit 15afd94a047 added code to acquire and release the AioContext in
qemuio_command(). This means that the lock is taken twice now in the
call path from hmp_qemu_io(). This causes BDRV_POLL_WHILE() to hang for
any requests issued to nodes in a non-mainloop AioContext.

Dropping the first locking from hmp_qemu_io() fixes the problem.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
---
 hmp.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/hmp.c b/hmp.c
index 35a7041824..2d72f94193 100644
--- a/hmp.c
+++ b/hmp.c
@@ -2318,7 +2318,6 @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict)
 {
     BlockBackend *blk;
     BlockBackend *local_blk = NULL;
-    AioContext *aio_context;
     const char* device = qdict_get_str(qdict, "device");
     const char* command = qdict_get_str(qdict, "command");
     Error *err = NULL;
@@ -2338,9 +2337,6 @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict)
         }
     }
 
-    aio_context = blk_get_aio_context(blk);
-    aio_context_acquire(aio_context);
-
     /*
      * Notably absent: Proper permission management. This is sad, but it seems
      * almost impossible to achieve without changing the semantics and thereby
@@ -2368,8 +2364,6 @@ void hmp_qemu_io(Monitor *mon, const QDict *qdict)
      */
     qemuio_command(blk, command);
 
-    aio_context_release(aio_context);
-
 fail:
     blk_unref(local_blk);
     hmp_handle_error(mon, &err);
-- 
2.13.6

  parent reply	other threads:[~2017-12-20 13:20 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-12-20 13:19 [Qemu-devel] [PULL 00/14] Block layer patches Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 01/14] hw/block/nvme: Convert to realize Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 02/14] block: Formats don't need CONSISTENT_READ with NO_IO Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 03/14] iotests: fix 197 for vpc Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 04/14] block: Make bdrv_drain_invoke() recursive Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 05/14] block: Call .drain_begin only once in bdrv_drain_all_begin() Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 06/14] test-bdrv-drain: Test BlockDriver callbacks for drain Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 07/14] block: bdrv_drain_recurse(): Remove unused begin parameter Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 08/14] block: Don't wait for requests in bdrv_drain*_end() Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 09/14] block: Unify order in drain functions Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 10/14] qemu-img: Document --force-share / -U Kevin Wolf
2017-12-20 13:19 ` Kevin Wolf [this message]
2017-12-20 13:19 ` [Qemu-devel] [PULL 12/14] qcow2: get rid of qcow2_backing_read1 routine Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 13/14] block: Document that x-blockdev-change breaks quorum children list Kevin Wolf
2017-12-20 13:19 ` [Qemu-devel] [PULL 14/14] nvme: Add tracing Kevin Wolf
2017-12-20 15:30 ` [Qemu-devel] [PULL 00/14] Block layer patches Peter Maydell

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