From mboxrd@z Thu Jan 1 00:00:00 1970 From: Hannes Reinecke Subject: Re: [PATCH v2 3/5] dm mpath: reduce size of multipath structure Date: Wed, 09 May 2012 08:58:53 +0200 Message-ID: <4FAA15AD.2040709@suse.de> References: <1336514167-15393-1-git-send-email-snitzer@redhat.com> <1336514167-15393-4-git-send-email-snitzer@redhat.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <1336514167-15393-4-git-send-email-snitzer@redhat.com> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mike Snitzer Cc: dm-devel@redhat.com, babu.moger@netapp.com, agk@redhat.com List-Id: dm-devel.ids On 05/08/2012 11:56 PM, Mike Snitzer wrote: > Move multipath structure's 'lock' and 'queue_size' members to eliminate > 2 4-byte holes. Also use a bit within a single unsigned int for each > existing flag (saves 8-bytes). This allows future flags to be added > without each consuming an unsigned int. > = > Signed-off-by: Mike Snitzer > --- > drivers/md/dm-mpath.c | 13 +++++++------ > 1 files changed, 7 insertions(+), 6 deletions(-) > = > diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c > index 754f38f..c351607 100644 > --- a/drivers/md/dm-mpath.c > +++ b/drivers/md/dm-mpath.c > @@ -61,11 +61,11 @@ struct multipath { > struct list_head list; > struct dm_target *ti; > = > - spinlock_t lock; > - > const char *hw_handler_name; > char *hw_handler_params; > = > + spinlock_t lock; > + > unsigned nr_priority_groups; > struct list_head priority_groups; > = > @@ -81,16 +81,17 @@ struct multipath { > struct priority_group *next_pg; /* Switch to this PG if set */ > unsigned repeat_count; /* I/Os left before calling PS again */ > = > - unsigned queue_io; /* Must we queue all I/O? */ > - unsigned queue_if_no_path; /* Queue I/O if last path fails? */ > - unsigned saved_queue_if_no_path;/* Saved state during suspension */ > + unsigned queue_io:1; /* Must we queue all I/O? */ > + unsigned queue_if_no_path:1; /* Queue I/O if last path fails? */ > + unsigned saved_queue_if_no_path:1; /* Saved state during suspension */ > + > unsigned pg_init_retries; /* Number of times to retry pg_init */ > unsigned pg_init_count; /* Number of times pg_init called */ > unsigned pg_init_delay_msecs; /* Number of msecs before pg_init retry */ > = > + unsigned queue_size; > struct work_struct process_queued_ios; > struct list_head queued_ios; > - unsigned queue_size; > = > struct work_struct trigger_event; > = Acked-by: Hannes Reinecke Cheers, Hannes -- = Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg GF: J. Hawn, J. Guild, F. Imend=F6rffer, HRB 16746 (AG N=FCrnberg)