From mboxrd@z Thu Jan 1 00:00:00 1970 From: Wengang Wang Date: Wed, 17 Nov 2010 09:12:35 +0800 Subject: [Ocfs2-devel] [PATCH] ocfs2/dlmfs: use GFP_KERNEL instead of GFP_NOFS In-Reply-To: <4CE2BD0C.3020501@oracle.com> References: <201011161537.oAG4gEQI002875@acsinet15.oracle.com> <4CE2BD0C.3020501@oracle.com> Message-ID: <20101117011235.GA2289@laptop.jp.oracle.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: ocfs2-devel@oss.oracle.com On 10-11-16 09:19, Sunil Mushran wrote: > We do NOFS allocs in the dlm to prevent deadlocks (not live locks). > And you are right we don't have to do NOFS allocs here. But the sizes > we are talking about are really small. Do we really care? I didn't hit problem at the allocation with NOFS. I just noticed it when looking at the codes. Since the sizes are small, it shouldn't effects much. The locks I meant is not dlm related. It's when system feel memory pressure and causes filesystems sync data to disk to free memory. During that time I think it's live lock if we allocate memory(GFP_KERNEL) when syncing data to disk. no? regards, wengang. > > On 11/16/2010 07:33 AM, Wengang Wang wrote: > >There is no need for dlmfs to sync data to disk so that no memory is needed > >for that purpose. So no worry about the live lock: sync data -> alloc mem -> > >sync data ->.... We'd better use GFP_KERNEL instead of GFP_NOFS to allow FS sync > >during the memory allocation. > >