lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

[S390] cio: wait for channel report

Browse Source 
To fetch a pending channel report word (crw) we use a kernel
thread which triggers stcrw and sleeps on a semaphore. The s390
machine check handler uses crw_handle_channel_report to handle
one crw if needed.

This patch replaces the semaphore with a waitqueue (to block the
kernel thread) and an atomic_t (to count the number of pending
requests).

By this we achieve the ability to force this thread to check for
a pending crw (independent on when it is triggered by the machine
check handler) and wait for this action to finish.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Sebastian Ott
2010-02-26 22:37:26 +01:00
committed by Martin Schwidefsky
parent 879acca58a
commit b4563e891a
2 changed files with 16 additions and 14 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
arch/s390/include/asm/crw.h
View File

@@ -32,6 +32,7 @@ typedef void (*crw_handler_t)(struct crw *, struct crw *, int);
extern int crw_register_handler(int rsc, crw_handler_t handler);
extern void crw_unregister_handler(int rsc);
extern void crw_handle_channel_report(void);
void crw_wait_for_channel_report(void);
#define NR_RSCS 16