Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Thu, 3 Jun 2021 10:43:24 +0200
From:   Jan Kara <jack@suse.cz>
To:     Amir Goldstein <amir73il@gmail.com>
Cc:     kernel test robot <oliver.sang@intel.com>, Jan Kara <jack@suse.cz>,
        Matthew Bobrowski <repnop@google.com>,
        Christian Brauner <christian.brauner@ubuntu.com>,
        LKML <linux-kernel@vger.kernel.org>, lkp@lists.01.org,
        kbuild test robot <lkp@intel.com>, ying.huang@intel.com,
        feng.tang@intel.com, zhengjun.xing@linux.intel.com,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [fanotify] a8b98c808e: stress-ng.fanotify.ops_per_sec 32.2%
 improvement
Message-ID: <20210603084324.GC23647@quack2.suse.cz>
References: <20210603015314.GA21290@xsang-OptiPlex-9020>
 <CAOQ4uxjdtfriARxh_CiTxFi8=T6j065HtbJGnuAas7oyPNADKg@mail.gmail.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <CAOQ4uxjdtfriARxh_CiTxFi8=T6j065HtbJGnuAas7oyPNADKg@mail.gmail.com>
User-Agent: Mutt/1.10.1 (2018-07-13)
Precedence: bulk

On Thu 03-06-21 09:57:15, Amir Goldstein wrote:
> On Thu, Jun 3, 2021 at 4:36 AM kernel test robot <oliver.sang@intel.com> wrote:
> >
> >
> >
> > Greeting,
> >
> > FYI, we noticed a 32.2% improvement of stress-ng.fanotify.ops_per_sec due to commit:
> >
> >
> > commit: a8b98c808eab3ec8f1b5a64be967b0f4af4cae43 ("fanotify: fix permission model of unprivileged group")
> > https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master
> >
> >
> 
> I guess now we know what caused the reported regression:
> https://lore.kernel.org/lkml/20210511124632.GL24154@quack2.suse.cz/
> 
> I didn't know that capable() is so significant.

Yeah, I wouldn't guess either. Interesting.

								Honza

-- 
Jan Kara <jack@suse.com>
SUSE Labs, CR