linux/include/scsi/libfc.h

1093 lines
28 KiB

[SCSI] fcoe, libfc: adds per cpu exch pool within exchange manager(EM) Adds per cpu exch pool for these reasons:- 1. Currently an EM instance is shared across all cpus to manage all exches for all cpus. This required em_lock across all cpus for an exch alloc, free, lookup and reset each frame and that made em_lock expensive, so instead having per cpu exch pool with their own per cpu pool lock will likely reduce locking contention in fast path for an exch alloc, free and lookup. 2. Per cpu exch pool will likely improve cache hit ratio since all frames of an exch will be processed on the same cpu on which exch originated. This patch is only prep work to help in keeping complexity of next patch low, so this patch only sets up per cpu exch pool and related helper funcs to be used by next patch. The next patch fully makes use of per cpu exch pool in all code paths ie. tx, rx and reset. Divides per EM exch id range equally across all cpus to setup per cpu exch pool. This division is such that lower bits of exch id carries cpu number info on which exch originated, later a simple bitwise AND operation on exch id of incoming frame with fc_cpu_mask retrieves cpu number info to direct all frames to same cpu on which exch originated. This required a global fc_cpu_mask and fc_cpu_order initialized to max possible cpus number nr_cpu_ids rounded up to 2's power, this will be used in mapping exch id and exch ptr array index in pool during exch allocation, find or reset code paths. Adds a check in fc_exch_mgr_alloc() to ensure specified min_xid lower bits are zero since these bits are used to carry cpu info. Adds and initializes struct fc_exch_pool with all required fields to manage exches in pool. Allocates per cpu struct fc_exch_pool with memory for exches array for range of exches per pool. The exches array memory is followed by struct fc_exch_pool. Adds fc_exch_ptr_get/set() helper functions to get/set exch ptr in pool exches array at specified array index. Increases default FCOE_MAX_XID to 0x0FFF from 0x07EF, so that more exches are available per cpu after above described exch id range division across all cpus to each pool. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-25 13:58:47 -07:00
[SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes em_lock 1. Updates fcoe_rcv() to queue incoming frames to the fcoe per cpu thread on which this frame's exch was originated and simply use current cpu for request exch not originated by initiator. It is redundant to add this code under CONFIG_SMP, so removes CONFIG_SMP uses around this code. 2. Updates fc_exch_em_alloc, fc_exch_delete, fc_exch_find to use per cpu exch pools, here fc_exch_delete is rename of older fc_exch_mgr_delete_ep since ep/exch are now deleted in pools of EM and so brief new name is sufficient and better name. Updates these functions to map exch id to their index into exch pool using fc_cpu_mask, fc_cpu_order and EM min_xid. This mapping is as per detailed explanation about this in last patch and basically this is just as lower fc_cpu_mask bits of exch id as cpu number and upper bit sum of EM min_xid and exch index in pool. Uses pool next_index to keep track of exch allocation from pool along with pool_max_index as upper bound of exches array in pool. 3. Adds exch pool ptr to fc_exch to free exch to its pool in fc_exch_delete. 4. Updates fc_exch_mgr_reset to reset all exch pools of an EM, this required adding fc_exch_pool_reset func to reset exches in pool and then have fc_exch_mgr_reset call fc_exch_pool_reset for each pool within each EM for a lport. 5. Removes no longer needed exches array, em_lock, next_xid, and total_exches from struct fc_exch_mgr, these are not needed after use of per cpu exch pool, also removes not used max_read, last_read from struct fc_exch_mgr. 6. Updates locking notes for exch pool lock with fc_exch lock and uses pool lock in exch allocation, lookup and reset. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-25 13:58:53 -07:00
[SCSI] libfc, fcoe: fixed locking issues with lport->lp_mutex around lport->link_status The fcoe_xmit could call fc_pause in case the pending skb queue len is larger than FCOE_MAX_QUEUE_DEPTH, the fc_pause was trying to grab lport->lp_muex to change lport->link_status and that had these issues :- 1. The fcoe_xmit was getting called with bh disabled, thus causing "BUG: scheduling while atomic" when grabbing lport->lp_muex with bh disabled. 2. fc_linkup and fc_linkdown function calls lport_enter function with lport->lp_mutex held and these enter function in turn calls fcoe_xmit to send lport related FC frame, e.g. fc_linkup => fc_lport_enter_flogi to send flogi req. In this case grabbing the same lport->lp_mutex again in fc_puase from fcoe_xmit would cause deadlock. The lport->lp_mutex was used for setting FC_PAUSE in fcoe_xmit path but FC_PAUSE bit was not used anywhere beside just setting and clear this bit in lport->link_status, instead used a separate field qfull in fc_lport to eliminate need for lport->lp_mutex to track pending queue full condition and in turn avoid above described two locking issues. Also added check for lp->qfull in fc_fcp_lport_queue_ready to trigger SCSI_MLQUEUE_HOST_BUSY when lp->qfull is set to prevent more scsi-ml cmds while lp->qfull is set. This patch eliminated FC_LINK_UP and FC_PAUSE and instead used dedicated fields in fc_lport for this, this simplified all related conditional code. Also removed fc_pause and fc_unpause functions and instead used newly added lport->qfull directly in fcoe. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2009-02-27 10:54:57 -08:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, fnic, libfc: modifies current code paths to use EM anchor list Modifies current code to use EM anchor list in EM allocation, EM free, EM reset, exch allocation and exch lookup code paths. 1. Modifies fc_exch_mgr_alloc to accept EM match function and then have allocated EM added to the lport using fc_exch_mgr_add API while also updating EM kref for newly added EM. 2. Updates fc_exch_mgr_free API to accept only lport pointer instead EM and then have this API free all EMs of the lport from EM anchor list. 3. Removes single lport pointer link from the EM, which was used in associating lport pointer in newly allocated exchange. Instead have lport pointer passed along new exchange allocation call path and then store passed lport pointer in newly allocated exchange, this will allow a single EM instance to be used across more than one lport and used in EM reset to reset only lport specific exchanges. 4. Modifies fc_exch_mgr_reset to reset all EMs from the EM anchor list of the lport, adds additional exch lport pointer (ep->lp) check for shared EM case to reset exchange specific to a lport requested reset. 5. Updates exch allocation API fc_exch_alloc to use EM anchor list and its anchor match func pointer. The fc_exch_alloc will walk the list of EMs until it finds a match, a match will be either null match func pointer or call to match function returning true value. 6. Updates fc_exch_recv to accept incoming frame on local port using only lport pointer and frame pointer without specifying EM instance of incoming frame. Instead modified fc_exch_recv to locate EM for the incoming frame by matching xid of incoming frame against a EM xid range. This change was required to use EM list in libfc Rx path and after this change the lport fc_exch_mgr pointer emp is not needed anymore, so removed emp pointer. 7. Updates fnic for removed lport emp pointer and above modified libfc APIs fc_exch_recv, fc_exch_mgr_alloc and fc_exch_mgr_free. 8. Removes exch_get and exch_put from libfc_function_template as these are no longer needed with EM anchor list and its match function use. Also removes its default function fc_exch_get. A defect this patch introduced regarding the libfc initialization order in the fnic driver was fixed by Joe Eykholt <jeykholt@cisco.com>. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-07-29 17:05:10 -07:00
[SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes em_lock 1. Updates fcoe_rcv() to queue incoming frames to the fcoe per cpu thread on which this frame's exch was originated and simply use current cpu for request exch not originated by initiator. It is redundant to add this code under CONFIG_SMP, so removes CONFIG_SMP uses around this code. 2. Updates fc_exch_em_alloc, fc_exch_delete, fc_exch_find to use per cpu exch pools, here fc_exch_delete is rename of older fc_exch_mgr_delete_ep since ep/exch are now deleted in pools of EM and so brief new name is sufficient and better name. Updates these functions to map exch id to their index into exch pool using fc_cpu_mask, fc_cpu_order and EM min_xid. This mapping is as per detailed explanation about this in last patch and basically this is just as lower fc_cpu_mask bits of exch id as cpu number and upper bit sum of EM min_xid and exch index in pool. Uses pool next_index to keep track of exch allocation from pool along with pool_max_index as upper bound of exches array in pool. 3. Adds exch pool ptr to fc_exch to free exch to its pool in fc_exch_delete. 4. Updates fc_exch_mgr_reset to reset all exch pools of an EM, this required adding fc_exch_pool_reset func to reset exches in pool and then have fc_exch_mgr_reset call fc_exch_pool_reset for each pool within each EM for a lport. 5. Removes no longer needed exches array, em_lock, next_xid, and total_exches from struct fc_exch_mgr, these are not needed after use of per cpu exch pool, also removes not used max_read, last_read from struct fc_exch_mgr. 6. Updates locking notes for exch pool lock with fc_exch lock and uses pool lock in exch allocation, lookup and reset. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-25 13:58:53 -07:00
[SCSI] fcoe, libfc: fully makes use of per cpu exch pool and then removes em_lock 1. Updates fcoe_rcv() to queue incoming frames to the fcoe per cpu thread on which this frame's exch was originated and simply use current cpu for request exch not originated by initiator. It is redundant to add this code under CONFIG_SMP, so removes CONFIG_SMP uses around this code. 2. Updates fc_exch_em_alloc, fc_exch_delete, fc_exch_find to use per cpu exch pools, here fc_exch_delete is rename of older fc_exch_mgr_delete_ep since ep/exch are now deleted in pools of EM and so brief new name is sufficient and better name. Updates these functions to map exch id to their index into exch pool using fc_cpu_mask, fc_cpu_order and EM min_xid. This mapping is as per detailed explanation about this in last patch and basically this is just as lower fc_cpu_mask bits of exch id as cpu number and upper bit sum of EM min_xid and exch index in pool. Uses pool next_index to keep track of exch allocation from pool along with pool_max_index as upper bound of exches array in pool. 3. Adds exch pool ptr to fc_exch to free exch to its pool in fc_exch_delete. 4. Updates fc_exch_mgr_reset to reset all exch pools of an EM, this required adding fc_exch_pool_reset func to reset exches in pool and then have fc_exch_mgr_reset call fc_exch_pool_reset for each pool within each EM for a lport. 5. Removes no longer needed exches array, em_lock, next_xid, and total_exches from struct fc_exch_mgr, these are not needed after use of per cpu exch pool, also removes not used max_read, last_read from struct fc_exch_mgr. 6. Updates locking notes for exch pool lock with fc_exch lock and uses pool lock in exch allocation, lookup and reset. Signed-off-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: Robert Love <robert.w.love@intel.com> Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-08-25 13:58:53 -07:00