Comments
Patch
@@ -3608,6 +3608,10 @@ check_rsp_state:
spin_lock_bh(&cmd->istate_lock);
cmd->i_state = ISTATE_SENT_STATUS;
spin_unlock_bh(&cmd->istate_lock);
+
+ if (atomic_read(&conn->check_immediate_queue))
+ return 1;
+
continue;
} else if (ret == 2) {
/* Still must send status,
@@ -3697,7 +3701,7 @@ check_rsp_state:
}
if (atomic_read(&conn->check_immediate_queue))
- break;
+ return 1;
}
return 0;
@@ -3741,12 +3745,15 @@ restart:
signal_pending(current))
goto transport_err;
+get_immediate:
ret = handle_immediate_queue(conn);
if (ret < 0)
goto transport_err;
ret = handle_response_queue(conn);
- if (ret == -EAGAIN)
+ if (ret == 1)
+ goto get_immediate;
+ else if (ret == -EAGAIN)
goto restart;
else if (ret < 0)
goto transport_err;
This is a note to let you know that I have just added a patch titled iscsi-target: Fix immediate queue starvation regression with to the linux-3.5.y-queue branch of the 3.5.y.z extended stable tree which can be found at: http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.5.y-queue If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.5.y.z tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ------ From beba5d727beeae6f12f12a1df21cfbe413b4a501 Mon Sep 17 00:00:00 2001 From: Nicholas Bellinger <nab@linux-iscsi.org> Date: Wed, 27 Feb 2013 17:53:52 -0800 Subject: [PATCH] iscsi-target: Fix immediate queue starvation regression with DATAIN commit fd3a9025c0349bc9b01d627529f54e6e1e389015 upstream. This patch addresses a v3.5+ regression in iscsi-target where TX thread process context -> handle_response_queue() execution is allowed to run unbounded while servicing constant outgoing flow of ISTATE_SEND_DATAIN response state. This ends up preventing memory release of StatSN acknowledged commands in a timely manner when under heavy large block streaming DATAIN workloads. The regression bug was initially introduced with: commit 6f3c0e69a9c20441bdc6d3b2d18b83b244384ec6 Author: Andy Grover <agrover@redhat.com> Date: Tue Apr 3 15:51:09 2012 -0700 target/iscsi: Refactor target_tx_thread immediate+response queue loops Go ahead and follow original iscsi_target_tx_thread() logic and check to break for immediate queue processing after each DataIN Sequence and/or Response PDU has been sent. Reported-by: Benjamin ESTRABAUD <be@mpstor.com> Cc: Andy Grover <agrover@redhat.com> Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/target/iscsi/iscsi_target.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) -- 1.8.1.2