From: Harvey Yang <harvey.huawei.yang@gmail.com>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
Matt Mooney <mfm@muteddisk.com>,
linux-usb@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, Harvey Yang <harvey.huawei.yang@gmail.com>
Subject: [PATCH 0/2] staging: usbip: refine the lock
Date: Tue, 8 Jan 2013 13:49:00 +0800 [thread overview]
Message-ID: <1357624142-7178-1-git-send-email-harvey.huawei.yang@gmail.com> (raw)
This patchset refines some spinlocks which maybe not used properly.
[PATCH 1/2]: The function 'usbip_event_add()' may be called in interrupt context on the stub side:
'stub_complete'->'stub_enqueue_ret_unlink'->'usbip_event_add'.
In this function it tries to get the lock 'ud->lock', so we should disable irq when we get this lock in process context.
[PATCH 2/2]: On the client side, we have a virtual hcd driver, there actually no hardware interrupts, so we do not need worry about race conditions caused by irq. To achieve a good performance there is no need to use the interrupt safe spinlock. Just replace them with a non interrupt safe version.
Harvey Yang (2):
staging: usbip: use interrupt safe spinlock to avoid potential
deadlock.
staging: usbip: replace the interrupt safe spinlocks with common
ones.
drivers/staging/usbip/stub_dev.c | 34 ++++++++--------
drivers/staging/usbip/stub_rx.c | 4 +-
drivers/staging/usbip/usbip_event.c | 6 ++-
drivers/staging/usbip/vhci_hcd.c | 76 +++++++++++++++--------------------
drivers/staging/usbip/vhci_rx.c | 10 ++---
drivers/staging/usbip/vhci_tx.c | 14 +++----
6 files changed, 65 insertions(+), 79 deletions(-)
next reply other threads:[~2013-01-08 5:44 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-08 5:49 Harvey Yang [this message]
2013-01-08 5:49 ` [PATCH 1/2] staging: usbip: use interrupt safe spinlock to avoid potential deadlock Harvey Yang
2013-01-08 5:51 ` Greg Kroah-Hartman
2013-01-08 5:49 ` [PATCH 2/2] staging: usbip: replace the interrupt safe spinlocks with common ones Harvey Yang
2013-01-08 5:52 ` [PATCH 0/2] staging: usbip: refine the lock Greg Kroah-Hartman
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1357624142-7178-1-git-send-email-harvey.huawei.yang@gmail.com \
--to=harvey.huawei.yang@gmail.com \
--cc=gregkh@linuxfoundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-usb@vger.kernel.org \
--cc=mfm@muteddisk.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®