OpenE2K
/
linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

target: Add transport_handle_cdb_direct optimization 

This patch adds a transport_handle_cdb_direct() optimization for mapping
and queueing tasks directly from within fabric processing context by calling
the newly exported transport_generic_new_cmd().  This currently expects to
be called from process context only, and will fail if called within interrupt
context.

This patch also leaves transport_generic_handle_cdb() unmodified for the
moment to function as expected with existing tcm_fc and ib_srpt fabrics,
and will be removed once these have been converted and tested with v4.1
code using transport_handle_cdb_direct().

Based on Andy's original patch here:

[PATCH 39/42] target: Call transport_new_cmd instead of adding to cmd queue

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Nicholas Bellinger 2011-06-03 20:59:19 -07:00
parent 35462975b2
commit 695434e1cb
2 changed files with 25 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
drivers/target/target_core_transport.c
View File

@ -1842,11 +1842,35 @@ int transport_generic_handle_cdb(
printk(KERN_ERR "cmd->se_lun is NULL\n");
return -EINVAL;
}
transport_add_cmd_to_queue(cmd, TRANSPORT_NEW_CMD);
return 0;
}
EXPORT_SYMBOL(transport_generic_handle_cdb);
/*
* Used by fabric module frontends to queue tasks directly.
* Many only be used from process context only
*/
int transport_handle_cdb_direct(
struct se_cmd *cmd)
{
if (!cmd->se_lun) {
dump_stack();
printk(KERN_ERR "cmd->se_lun is NULL\n");
return -EINVAL;
}
if (in_interrupt()) {
dump_stack();
printk(KERN_ERR "transport_generic_handle_cdb cannot be called"
" from interrupt context\n");
return -EINVAL;
}
return transport_generic_new_cmd(cmd);
}
EXPORT_SYMBOL(transport_handle_cdb_direct);
/*
* Used by fabric module frontends defining a TFO->new_cmd_map() caller
* to queue up a newly setup se_cmd w/ TRANSPORT_NEW_CMD_MAP in order to

1
include/target/target_core_transport.h
View File

@ -166,6 +166,7 @@ extern void transport_init_se_cmd(struct se_cmd *,
extern void transport_free_se_cmd(struct se_cmd *);
extern int transport_generic_allocate_tasks(struct se_cmd *, unsigned char *);
extern int transport_generic_handle_cdb(struct se_cmd *);
extern int transport_handle_cdb_direct(struct se_cmd *);
extern int transport_generic_handle_cdb_map(struct se_cmd *);
extern int transport_generic_handle_data(struct se_cmd *);
extern void transport_new_cmd_failure(struct se_cmd *);