block: fix linkage problem with blk_iopoll and !CONFIG_BLOCK

kernel/built-in.o:(.data+0x17b0): undefined reference to `blk_iopoll_enabled'

Since the extern declaration makes the compile work, but the actual
symbol is missing when block/blk-iopoll.o isn't linked in.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
This commit is contained in:
Jens Axboe 2009-09-15 21:53:11 +02:00
parent 1824090496
commit cb684b5bcd

View file

@ -91,7 +91,9 @@ extern int sysctl_nr_trim_pages;
#ifdef CONFIG_RCU_TORTURE_TEST
extern int rcutorture_runnable;
#endif /* #ifdef CONFIG_RCU_TORTURE_TEST */
#ifdef CONFIG_BLOCK
extern int blk_iopoll_enabled;
#endif
/* Constants used for minimum and maximum */
#ifdef CONFIG_DETECT_SOFTLOCKUP
@ -998,6 +1000,7 @@ static struct ctl_table kern_table[] = {
.proc_handler = &proc_dointvec,
},
#endif
#ifdef CONFIG_BLOCK
{
.ctl_name = CTL_UNNUMBERED,
.procname = "blk_iopoll",
@ -1006,6 +1009,7 @@ static struct ctl_table kern_table[] = {
.mode = 0644,
.proc_handler = &proc_dointvec,
},
#endif
/*
* NOTE: do not add new entries to this table unless you have read
* Documentation/sysctl/ctl_unnumbered.txt