From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Doug Ledford <dledford@redhat.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>,
Dan Carpenter <dan.carpenter@oracle.com>,
Mike Marciniszyn <mike.marciniszyn@intel.com>,
Sean Hefty <sean.hefty@intel.com>,
Hal Rosenstock <hal.rosenstock@gmail.com>,
linux-rdma@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] IB/hfi1: Fix a wrapping test (make it less strict)
Date: Mon, 23 Oct 2017 19:04:00 +0000 [thread overview]
Message-ID: <20171023190400.GA24412@obsidianresearch.com> (raw)
In-Reply-To: <1508783626.3325.16.camel@redhat.com>
On Mon, Oct 23, 2017 at 02:33:46PM -0400, Doug Ledford wrote:
> > > > @@ -3781,7 +3781,7 @@ static int
> > > > __subn_get_opa_hfi1_cong_log(struct
> > > > opa_smp *smp, u32 am,
> > > > * required to wrap the counter are supposed to
> > > > * be zeroed (CA10-49 IBTA, release 1.2.1, V1).
> > > > */
> > > > - if ((u64)(ts - cce->timestamp) > (2 * UINT_MAX))
> > > > + if ((u64)(ts - cce->timestamp) > (2ULL *
> > > > UINT_MAX))
This is really weird looking. Both ts and cce->timestamp are s64, why
do the convoluted conversion to unsigned? And surely UINT_MAX is not
the right thing..
if ((ts - cce->timestamp)/2 > 0xFFFFFFFF)
?
ktime_get is defined to be monotonic, so ts - cce->timestamp should
never go negative.
Jason
WARNING: multiple messages have this Message-ID (diff)
From: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
To: Doug Ledford <dledford@redhat.com>
Cc: Dennis Dalessandro <dennis.dalessandro@intel.com>,
Dan Carpenter <dan.carpenter@oracle.com>,
Mike Marciniszyn <mike.marciniszyn@intel.com>,
Sean Hefty <sean.hefty@intel.com>,
Hal Rosenstock <hal.rosenstock@gmail.com>,
linux-rdma@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: Re: [PATCH] IB/hfi1: Fix a wrapping test (make it less strict)
Date: Mon, 23 Oct 2017 13:04:00 -0600 [thread overview]
Message-ID: <20171023190400.GA24412@obsidianresearch.com> (raw)
In-Reply-To: <1508783626.3325.16.camel@redhat.com>
On Mon, Oct 23, 2017 at 02:33:46PM -0400, Doug Ledford wrote:
> > > > @@ -3781,7 +3781,7 @@ static int
> > > > __subn_get_opa_hfi1_cong_log(struct
> > > > opa_smp *smp, u32 am,
> > > > * required to wrap the counter are supposed to
> > > > * be zeroed (CA10-49 IBTA, release 1.2.1, V1).
> > > > */
> > > > - if ((u64)(ts - cce->timestamp) > (2 * UINT_MAX))
> > > > + if ((u64)(ts - cce->timestamp) > (2ULL *
> > > > UINT_MAX))
This is really weird looking. Both ts and cce->timestamp are s64, why
do the convoluted conversion to unsigned? And surely UINT_MAX is not
the right thing..
if ((ts - cce->timestamp)/2 > 0xFFFFFFFF)
?
ktime_get is defined to be monotonic, so ts - cce->timestamp should
never go negative.
Jason
next prev parent reply other threads:[~2017-10-23 19:04 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-13 10:56 [PATCH] IB/hfi1: Fix a wrapping test (make it less strict) Dan Carpenter
2017-10-13 10:56 ` Dan Carpenter
2017-10-23 15:05 ` Doug Ledford
2017-10-23 15:05 ` Doug Ledford
[not found] ` <1508771116.3325.0.camel-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2017-10-23 17:57 ` Dennis Dalessandro
2017-10-23 17:57 ` Dennis Dalessandro
2017-10-23 18:33 ` Doug Ledford
2017-10-23 18:33 ` Doug Ledford
2017-10-23 19:04 ` Jason Gunthorpe [this message]
2017-10-23 19:04 ` Jason Gunthorpe
2017-10-24 19:54 ` Marciniszyn, Mike
[not found] ` <32E1700B9017364D9B60AED9960492BC3443EB1C-RjuIdWtd+YbTXloPLtfHfbfspsVTdybXVpNB7YpNyf8@public.gmane.org>
2017-10-24 20:02 ` Jason Gunthorpe
2017-10-24 20:02 ` Jason Gunthorpe
[not found] ` <20171024200216.GA15994-ePGOBjL8dl3ta4EC/59zMFaTQe2KTcn/@public.gmane.org>
2017-10-24 20:03 ` Marciniszyn, Mike
2017-10-24 20:03 ` Marciniszyn, Mike
2017-10-25 5:27 ` Dan Carpenter
2017-10-25 5:27 ` Dan Carpenter
2017-10-25 5:14 ` Dan Carpenter
2017-10-25 5:14 ` Dan Carpenter
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=20171023190400.GA24412@obsidianresearch.com \
--to=jgunthorpe@obsidianresearch.com \
--cc=dan.carpenter@oracle.com \
--cc=dennis.dalessandro@intel.com \
--cc=dledford@redhat.com \
--cc=hal.rosenstock@gmail.com \
--cc=kernel-janitors@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=mike.marciniszyn@intel.com \
--cc=sean.hefty@intel.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.