Module Name: src
Committed By: ahoka
Date: Sun May 1 14:48:11 UTC 2011
Modified Files:
src/sys/dev/nand: nand.h nand_io.c
Log Message:
fix some bugs and simplify locking
from rmind
To generate a diff of this commit:
cvs rdiff -u -r1.8 -r1.9 src/sys/dev/nand/nand.h
cvs rdiff -u -r1.5 -r1.6 src/sys/dev/nand/nand_io.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/dev/nand/nand.h
diff -u src/sys/dev/nand/nand.h:1.8 src/sys/dev/nand/nand.h:1.9
--- src/sys/dev/nand/nand.h:1.8 Tue Apr 26 17:31:57 2011
+++ src/sys/dev/nand/nand.h Sun May 1 14:48:11 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: nand.h,v 1.8 2011/04/26 17:31:57 ahoka Exp $ */
+/* $NetBSD: nand.h,v 1.9 2011/05/01 14:48:11 ahoka Exp $ */
/*-
* Copyright (c) 2010 Department of Software Engineering,
@@ -141,6 +141,9 @@
daddr_t nwc_block;
kmutex_t nwc_lock;
bool nwc_write_pending;
+ struct lwp *nwc_thread;
+ kcondvar_t nwc_cv;
+ bool nwc_exiting;
};
/* driver softc for nand */
@@ -154,13 +157,7 @@
size_t sc_part_offset;
size_t sc_part_size;
kmutex_t sc_device_lock; /* serialize access to chip */
-
- /* for the i/o thread */
- struct lwp *sc_sync_thread;
struct nand_write_cache sc_cache;
- kmutex_t sc_io_lock;
- kcondvar_t sc_io_cv;
- bool sc_io_running;
};
/* structure holding the nand api */
Index: src/sys/dev/nand/nand_io.c
diff -u src/sys/dev/nand/nand_io.c:1.5 src/sys/dev/nand/nand_io.c:1.6
--- src/sys/dev/nand/nand_io.c:1.5 Sun May 1 13:20:28 2011
+++ src/sys/dev/nand/nand_io.c Sun May 1 14:48:11 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: nand_io.c,v 1.5 2011/05/01 13:20:28 rmind Exp $ */
+/* $NetBSD: nand_io.c,v 1.6 2011/05/01 14:48:11 ahoka Exp $ */
/*-
* Copyright (c) 2011 Department of Software Engineering,
@@ -37,7 +37,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: nand_io.c,v 1.5 2011/05/01 13:20:28 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: nand_io.c,v 1.6 2011/05/01 14:48:11 ahoka Exp $");
#include <sys/param.h>
#include <sys/buf.h>
@@ -109,31 +109,27 @@
sc->sc_cache.nwc_data = kmem_alloc(chip->nc_block_size, KM_SLEEP);
- mutex_init(&sc->sc_io_lock, MUTEX_DEFAULT, IPL_NONE);
mutex_init(&wc->nwc_lock, MUTEX_DEFAULT, IPL_NONE);
- cv_init(&sc->sc_io_cv, "nandcv");
+ cv_init(&wc->nwc_cv, "nandcv");
error = bufq_alloc(&wc->nwc_bufq, "fcfs", BUFQ_SORT_RAWBLOCK);
if (error)
goto err_bufq;
- sc->sc_io_running = true;
+ wc->nwc_exiting = false;
wc->nwc_write_pending = false;
/* arrange to allocate the kthread */
error = kthread_create(PRI_NONE, KTHREAD_JOINABLE | KTHREAD_MPSAFE,
- NULL, nand_sync_thread, self, &sc->sc_sync_thread, "nandio");
+ NULL, nand_sync_thread, self, &wc->nwc_thread, "nandio");
if (!error)
return 0;
bufq_free(wc->nwc_bufq);
err_bufq:
- cv_destroy(&sc->sc_io_cv);
-
- mutex_destroy(&sc->sc_io_lock);
+ cv_destroy(&wc->nwc_cv);
mutex_destroy(&wc->nwc_lock);
-
kmem_free(sc->sc_cache.nwc_data, chip->nc_block_size);
return error;
@@ -148,27 +144,17 @@
DPRINTF(("stopping nand io thread\n"));
- kmem_free(wc->nwc_data, chip->nc_block_size);
-
- sc->sc_io_running = false;
-
- mutex_enter(&sc->sc_io_lock);
- cv_broadcast(&sc->sc_io_cv);
- mutex_exit(&sc->sc_io_lock);
+ mutex_enter(&wc->nwc_lock);
+ wc->nwc_exiting = true;
+ cv_broadcast(&wc->nwc_cv);
+ mutex_exit(&wc->nwc_lock);
- kthread_join(sc->sc_sync_thread);
+ kthread_join(wc->nwc_thread);
+ kmem_free(wc->nwc_data, chip->nc_block_size);
bufq_free(wc->nwc_bufq);
mutex_destroy(&wc->nwc_lock);
-
-#ifdef DIAGNOSTIC
- mutex_enter(&sc->sc_io_lock);
- KASSERT(!cv_has_waiters(&sc->sc_io_cv));
- mutex_exit(&sc->sc_io_lock);
-#endif
-
- cv_destroy(&sc->sc_io_cv);
- mutex_destroy(&sc->sc_io_lock);
+ cv_destroy(&wc->nwc_cv);
}
int
@@ -179,7 +165,7 @@
DPRINTF(("submitting job to nand io thread: %p\n", bp));
- if (__predict_false(!sc->sc_io_running)) {
+ if (__predict_false(wc->nwc_exiting)) {
nand_io_done(self, bp, ENODEV);
return ENODEV;
}
@@ -211,6 +197,7 @@
daddr_t base, offset;
int error;
+ KASSERT(mutex_owned(&wc->nwc_lock));
KASSERT(chip->nc_block_size != 0);
base = block * chip->nc_block_size;
@@ -247,7 +234,6 @@
return 0;
}
-/* must be called with nwc_lock hold */
void
nand_io_cache_sync(device_t self)
{
@@ -260,6 +246,8 @@
daddr_t base;
int error;
+ KASSERT(mutex_owned(&wc->nwc_lock));
+
if (!wc->nwc_write_pending) {
DPRINTF(("trying to sync with an invalid buffer\n"));
return;
@@ -305,18 +293,12 @@
struct nand_write_cache *wc = &sc->sc_cache;
struct bintime now;
- /* sync thread waking in every seconds */
- while (sc->sc_io_running) {
- mutex_enter(&sc->sc_io_lock);
- cv_timedwait_sig(&sc->sc_io_cv, &sc->sc_io_lock, hz / 4);
- mutex_exit(&sc->sc_io_lock);
-
- mutex_enter(&wc->nwc_lock);
+ mutex_enter(&wc->nwc_lock);
+ while (!wc->nwc_exiting) {
+ cv_timedwait_sig(&wc->nwc_cv, &wc->nwc_lock, hz / 4);
if (!wc->nwc_write_pending) {
- mutex_exit(&wc->nwc_lock);
continue;
}
-
/* see if the cache is older than 3 seconds (safety limit),
* or if we havent touched the cache since more than 1 ms
*/
@@ -328,8 +310,8 @@
printf("syncing write cache after timeout\n");
nand_io_cache_sync(self);
}
- mutex_exit(&wc->nwc_lock);
}
+ mutex_exit(&wc->nwc_lock);
kthread_exit(0);
}
