projects / ipfire-2.x.git / blame
| Commit | Line | Data |
|---|---|---|
| 4d1e5b62 AF |
1 | From: Vasu Dev <vasu.dev@intel.com> |
| 2 | Subject: [FcOE] updated comment for order of em and ex locks | |
| 3 | References: bnc #459142 | |
| 4 | ||
| 5 | The fc_exch is public but em_lock is static to fc_exch.c, | |
| 6 | so updated comment only in fc_exch.c on order of these locks. | |
| 7 | ||
| 8 | Also removed seq.f_ctl from comments since this field is | |
| 9 | already removed. | |
| 10 | ||
| 11 | Signed-off-by: Vasu Dev <vasu.dev@intel.com> | |
| 12 | Acked-by: Bernhard Walle <bwalle@suse.de> | |
| 13 | --- | |
| 14 | ||
| 15 | drivers/scsi/libfc/fc_exch.c | 5 ++++- | |
| 16 | include/scsi/libfc.h | 5 ++--- | |
| 17 | 2 files changed, 6 insertions(+), 4 deletions(-) | |
| 18 | ||
| 19 | ||
| 20 | --- a/drivers/scsi/libfc/fc_exch.c | |
| 21 | +++ b/drivers/scsi/libfc/fc_exch.c | |
| 22 | @@ -68,7 +68,8 @@ static struct kmem_cache *fc_em_cachep; | |
| 23 | */ | |
| 24 | struct fc_exch_mgr { | |
| 25 | enum fc_class class; /* default class for sequences */ | |
| 26 | - spinlock_t em_lock; /* exchange manager lock */ | |
| 27 | + spinlock_t em_lock; /* exchange manager lock, | |
| 28 | + must be taken before ex_lock */ | |
| 29 | u16 last_xid; /* last allocated exchange ID */ | |
| 30 | u16 min_xid; /* min exchange ID */ | |
| 31 | u16 max_xid; /* max exchange ID */ | |
| 32 | @@ -179,6 +180,8 @@ static struct fc_seq *fc_seq_start_next_ | |
| 33 | * sequence allocation and deallocation must be locked. | |
| 34 | * - exchange refcnt can be done atomicly without locks. | |
| 35 | * - sequence allocation must be locked by exch lock. | |
| 36 | + * - If the em_lock and ex_lock must be taken at the same time, then the | |
| 37 | + * em_lock must be taken before the ex_lock. | |
| 38 | */ | |
| 39 | ||
| 40 | /* | |
| 41 | --- a/include/scsi/libfc.h | |
| 42 | +++ b/include/scsi/libfc.h | |
| 43 | @@ -299,11 +299,10 @@ struct fc_seq { | |
| 44 | /* | |
| 45 | * Exchange. | |
| 46 | * | |
| 47 | - * Locking notes: The ex_lock protects changes to the following fields: | |
| 48 | - * esb_stat, f_ctl, seq.ssb_stat, seq.f_ctl. | |
| 49 | + * Locking notes: The ex_lock protects following items: | |
| 50 | + * state, esb_stat, f_ctl, seq.ssb_stat | |
| 51 | * seq_id | |
| 52 | * sequence allocation | |
| 53 | - * | |
| 54 | */ | |
| 55 | struct fc_exch { | |
| 56 | struct fc_exch_mgr *em; /* exchange manager */ |