gigaset: atomic cleanup

Convert atomic_t variables that don't actually use atomic_t functionality
to int.
Signed-off-by: Tilman Schmidt <tilman@imap.cc>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/isdn/gigaset/asyncdata.c

@@ -350,8 +350,8 @@ void gigaset_m10x_input(struct inbuf_t *inbuf)
 	unsigned char *src, c;
 	int procbytes;
 
-	head = atomic_read(&inbuf->head);
-	tail = atomic_read(&inbuf->tail);
+	head = inbuf->head;
+	tail = inbuf->tail;
 	gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
 
 	if (head != tail) {
@@ -361,7 +361,7 @@ void gigaset_m10x_input(struct inbuf_t *inbuf)
 		gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes);
 
 		while (numbytes) {
-			if (atomic_read(&cs->mstate) == MS_LOCKED) {
+			if (cs->mstate == MS_LOCKED) {
 				procbytes = lock_loop(src, numbytes, inbuf);
 				src += procbytes;
 				numbytes -= procbytes;
@@ -436,7 +436,7 @@ void gigaset_m10x_input(struct inbuf_t *inbuf)
 		}
 
 		gig_dbg(DEBUG_INTR, "setting head to %u", head);
-		atomic_set(&inbuf->head, head);
+		inbuf->head = head;
 	}
 }
 EXPORT_SYMBOL_GPL(gigaset_m10x_input);

drivers/isdn/gigaset/common.c

@@ -501,11 +501,11 @@ static void gigaset_inbuf_init(struct inbuf_t *inbuf, struct bc_state *bcs,
 			       struct cardstate *cs, int inputstate)
 /* inbuf->read must be allocated before! */
 {
-	atomic_set(&inbuf->head, 0);
-	atomic_set(&inbuf->tail, 0);
+	inbuf->head = 0;
+	inbuf->tail = 0;
 	inbuf->cs = cs;
 	inbuf->bcs = bcs; /*base driver: NULL*/
-	inbuf->rcvbuf = NULL; //FIXME
+	inbuf->rcvbuf = NULL;
 	inbuf->inputstate = inputstate;
 }
 
@@ -521,8 +521,8 @@ int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 		return 0;
 
 	bytesleft = numbytes;
-	tail = atomic_read(&inbuf->tail);
-	head = atomic_read(&inbuf->head);
+	tail = inbuf->tail;
+	head = inbuf->head;
 	gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
 
 	while (bytesleft) {
@@ -546,7 +546,7 @@ int gigaset_fill_inbuf(struct inbuf_t *inbuf, const unsigned char *src,
 		src += n;
 	}
 	gig_dbg(DEBUG_INTR, "setting tail to %u", tail);
-	atomic_set(&inbuf->tail, tail);
+	inbuf->tail = tail;
 	return numbytes != bytesleft;
 }
 EXPORT_SYMBOL_GPL(gigaset_fill_inbuf);
@@ -668,7 +668,7 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 
 	tasklet_init(&cs->event_tasklet, &gigaset_handle_event,
 		     (unsigned long) cs);
-	atomic_set(&cs->commands_pending, 0);
+	cs->commands_pending = 0;
 	cs->cur_at_seq = 0;
 	cs->gotfwver = -1;
 	cs->open_count = 0;
@@ -688,8 +688,8 @@ struct cardstate *gigaset_initcs(struct gigaset_driver *drv, int channels,
 	init_waitqueue_head(&cs->waitqueue);
 	cs->waiting = 0;
 
-	atomic_set(&cs->mode, M_UNKNOWN);
-	atomic_set(&cs->mstate, MS_UNINITIALIZED);
+	cs->mode = M_UNKNOWN;
+	cs->mstate = MS_UNINITIALIZED;
 
 	for (i = 0; i < channels; ++i) {
 		gig_dbg(DEBUG_INIT, "setting up bcs[%d].read", i);
@@ -806,8 +806,8 @@ static void cleanup_cs(struct cardstate *cs)
 
 	spin_lock_irqsave(&cs->lock, flags);
 
-	atomic_set(&cs->mode, M_UNKNOWN);
-	atomic_set(&cs->mstate, MS_UNINITIALIZED);
+	cs->mode = M_UNKNOWN;
+	cs->mstate = MS_UNINITIALIZED;
 
 	clear_at_state(&cs->at_state);
 	dealloc_at_states(cs);
@@ -817,8 +817,8 @@ static void cleanup_cs(struct cardstate *cs)
 	kfree(cs->inbuf->rcvbuf);
 	cs->inbuf->rcvbuf = NULL;
 	cs->inbuf->inputstate = INS_command;
-	atomic_set(&cs->inbuf->head, 0);
-	atomic_set(&cs->inbuf->tail, 0);
+	cs->inbuf->head = 0;
+	cs->inbuf->tail = 0;
 
 	cb = cs->cmdbuf;
 	while (cb) {
@@ -832,7 +832,7 @@ static void cleanup_cs(struct cardstate *cs)
 	cs->gotfwver = -1;
 	cs->dle = 0;
 	cs->cur_at_seq = 0;
-	atomic_set(&cs->commands_pending, 0);
+	cs->commands_pending = 0;
 	cs->cbytes = 0;
 
 	spin_unlock_irqrestore(&cs->lock, flags);
@@ -862,7 +862,7 @@ int gigaset_start(struct cardstate *cs)
 	cs->connected = 1;
 	spin_unlock_irqrestore(&cs->lock, flags);
 
-	if (atomic_read(&cs->mstate) != MS_LOCKED) {
+	if (cs->mstate != MS_LOCKED) {
 		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
 		cs->ops->baud_rate(cs, B115200);
 		cs->ops->set_line_ctrl(cs, CS8);

drivers/isdn/gigaset/gigaset.h

@@ -307,7 +307,7 @@ struct inbuf_t {
 	struct bc_state		*bcs;
 	struct cardstate	*cs;
 	int			inputstate;
-	atomic_t		head, tail;
+	int			head, tail;
 	unsigned char		data[RBUFSIZE];
 };
 
@@ -329,9 +329,9 @@ struct inbuf_t {
  *   are also filled with that value
  */
 struct isowbuf_t {
-	atomic_t	read;
-	atomic_t	nextread;
-	atomic_t	write;
+	int		read;
+	int		nextread;
+	int		write;
 	atomic_t	writesem;
 	int		wbits;
 	unsigned char	data[BAS_OUTBUFSIZE + BAS_OUTBUFPAD];
@@ -441,8 +441,8 @@ struct cardstate {
 	/* Stuff to handle communication */
 	wait_queue_head_t waitqueue;
 	int waiting;
-	atomic_t mode;			/* see M_XXXX */
-	atomic_t mstate;		/* Modem state: see MS_XXXX */
+	int mode;			/* see M_XXXX */
+	int mstate;			/* Modem state: see MS_XXXX */
 					/* only changed by the event layer */
 	int cmd_result;
 
@@ -499,7 +499,7 @@ struct cardstate {
 					   processed */
 	int curchannel;			/* channel those commands are meant
 					   for */
-	atomic_t commands_pending;	/* flag(s) in xxx.commands_pending have
+	int commands_pending;		/* flag(s) in xxx.commands_pending have
 					   been set */
 	struct tasklet_struct event_tasklet;
 					/* tasklet for serializing AT commands.
@@ -555,7 +555,7 @@ struct cmdbuf_t {
 
 struct bas_bc_state {
 	/* isochronous output state */
-	atomic_t	running;
+	int		running;
 	atomic_t	corrbytes;
 	spinlock_t	isooutlock;
 	struct isow_urbctx_t	isoouturbs[BAS_OUTURBS];

drivers/isdn/gigaset/interface.c

@@ -28,12 +28,11 @@ static int if_lock(struct cardstate *cs, int *arg)
 		return -EINVAL;
 
 	if (cmd < 0) {
-		*arg = atomic_read(&cs->mstate) == MS_LOCKED; //FIXME remove?
+		*arg = cs->mstate == MS_LOCKED;
 		return 0;
 	}
 
-	if (!cmd && atomic_read(&cs->mstate) == MS_LOCKED
-	    && cs->connected) {
+	if (!cmd && cs->mstate == MS_LOCKED && cs->connected) {
 		cs->ops->set_modem_ctrl(cs, 0, TIOCM_DTR|TIOCM_RTS);
 		cs->ops->baud_rate(cs, B115200);
 		cs->ops->set_line_ctrl(cs, CS8);
@@ -104,7 +103,7 @@ static int if_config(struct cardstate *cs, int *arg)
 	if (*arg != 1)
 		return -EINVAL;
 
-	if (atomic_read(&cs->mstate) != MS_LOCKED)
+	if (cs->mstate != MS_LOCKED)
 		return -EBUSY;
 
 	if (!cs->connected) {
@@ -364,7 +363,7 @@ static int if_write(struct tty_struct *tty, const unsigned char *buf, int count)
 
 	if (!cs->open_count)
 		warn("%s: device not opened", __func__);
-	else if (atomic_read(&cs->mstate) != MS_LOCKED) {
+	else if (cs->mstate != MS_LOCKED) {
 		warn("can't write to unlocked device");
 		retval = -EBUSY;
 	} else if (!cs->connected) {
@@ -398,9 +397,9 @@ static int if_write_room(struct tty_struct *tty)
 
 	if (!cs->open_count)
 		warn("%s: device not opened", __func__);
-	else if (atomic_read(&cs->mstate) != MS_LOCKED) {
+	else if (cs->mstate != MS_LOCKED) {
 		warn("can't write to unlocked device");
-		retval = -EBUSY; //FIXME
+		retval = -EBUSY;
 	} else if (!cs->connected) {
 		gig_dbg(DEBUG_ANY, "can't write to unplugged device");
 		retval = -EBUSY; //FIXME
@@ -430,7 +429,7 @@ static int if_chars_in_buffer(struct tty_struct *tty)
 
 	if (!cs->open_count)
 		warn("%s: device not opened", __func__);
-	else if (atomic_read(&cs->mstate) != MS_LOCKED) {
+	else if (cs->mstate != MS_LOCKED) {
 		warn("can't write to unlocked device");
 		retval = -EBUSY;
 	} else if (!cs->connected) {

drivers/isdn/gigaset/isocdata.c

@@ -23,9 +23,9 @@
  */
 void gigaset_isowbuf_init(struct isowbuf_t *iwb, unsigned char idle)
 {
-	atomic_set(&iwb->read, 0);
-	atomic_set(&iwb->nextread, 0);
-	atomic_set(&iwb->write, 0);
+	iwb->read = 0;
+	iwb->nextread = 0;
+	iwb->write = 0;
 	atomic_set(&iwb->writesem, 1);
 	iwb->wbits = 0;
 	iwb->idle = idle;
@@ -39,8 +39,8 @@ static inline int isowbuf_freebytes(struct isowbuf_t *iwb)
 {
 	int read, write, freebytes;
 
-	read = atomic_read(&iwb->read);
-	write = atomic_read(&iwb->write);
+	read = iwb->read;
+	write = iwb->write;
 	if ((freebytes = read - write) > 0) {
 		/* no wraparound: need padding space within regular area */
 		return freebytes - BAS_OUTBUFPAD;
@@ -62,7 +62,7 @@ static inline int isowbuf_poscmp(struct isowbuf_t *iwb, int a, int b)
 	int read;
 	if (a == b)
 		return 0;
-	read = atomic_read(&iwb->read);
+	read = iwb->read;
 	if (a < b) {
 		if (a < read && read <= b)
 			return +1;
@@ -91,18 +91,18 @@ static inline int isowbuf_startwrite(struct isowbuf_t *iwb)
 #ifdef CONFIG_GIGASET_DEBUG
 	gig_dbg(DEBUG_ISO,
 		"%s: acquired iso write semaphore, data[write]=%02x, nbits=%d",
-		__func__, iwb->data[atomic_read(&iwb->write)], iwb->wbits);
+		__func__, iwb->data[iwb->write], iwb->wbits);
 #endif
 	return 1;
 }
 
 /* finish writing
- * release the write semaphore and update the maximum buffer fill level
+ * release the write semaphore
  * returns the current write position
  */
 static inline int isowbuf_donewrite(struct isowbuf_t *iwb)
 {
-	int write = atomic_read(&iwb->write);
+	int write = iwb->write;
 	atomic_inc(&iwb->writesem);
 	return write;
 }
@@ -116,7 +116,7 @@ static inline int isowbuf_donewrite(struct isowbuf_t *iwb)
  */
 static inline void isowbuf_putbits(struct isowbuf_t *iwb, u32 data, int nbits)
 {
-	int write = atomic_read(&iwb->write);
+	int write = iwb->write;
 	data <<= iwb->wbits;
 	data |= iwb->data[write];
 	nbits += iwb->wbits;
@@ -128,7 +128,7 @@ static inline void isowbuf_putbits(struct isowbuf_t *iwb, u32 data, int nbits)
 	}
 	iwb->wbits = nbits;
 	iwb->data[write] = data & 0xff;
-	atomic_set(&iwb->write, write);
+	iwb->write = write;
 }
 
 /* put final flag on HDLC bitstream
@@ -142,7 +142,7 @@ static inline void isowbuf_putflag(struct isowbuf_t *iwb)
 	/* add two flags, thus reliably covering one byte */
 	isowbuf_putbits(iwb, 0x7e7e, 8);
 	/* recover the idle flag byte */
-	write = atomic_read(&iwb->write);
+	write = iwb->write;
 	iwb->idle = iwb->data[write];
 	gig_dbg(DEBUG_ISO, "idle fill byte %02x", iwb->idle);
 	/* mask extraneous bits in buffer */
@@ -160,8 +160,8 @@ int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
 	int read, write, limit, src, dst;
 	unsigned char pbyte;
 
-	read = atomic_read(&iwb->nextread);
-	write = atomic_read(&iwb->write);
+	read = iwb->nextread;
+	write = iwb->write;
 	if (likely(read == write)) {
 		/* return idle frame */
 		return read < BAS_OUTBUFPAD ?
@@ -176,7 +176,7 @@ int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
 		err("invalid size %d", size);
 		return -EINVAL;
 	}
-	src = atomic_read(&iwb->read);
+	src = iwb->read;
 	if (unlikely(limit > BAS_OUTBUFSIZE + BAS_OUTBUFPAD ||
 		     (read < src && limit >= src))) {
 		err("isoc write buffer frame reservation violated");
@@ -191,7 +191,8 @@ int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
 			if (!isowbuf_startwrite(iwb))
 				return -EBUSY;
 			/* write position could have changed */
-			if (limit >= (write = atomic_read(&iwb->write))) {
+			write = iwb->write;
+			if (limit >= write) {
 				pbyte = iwb->data[write]; /* save
 							     partial byte */
 				limit = write + BAS_OUTBUFPAD;
@@ -213,7 +214,7 @@ int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
 					__func__, pbyte, limit);
 				iwb->data[limit] = pbyte; /* restore
 							     partial byte */
-				atomic_set(&iwb->write, limit);
+				iwb->write = limit;
 			}
 			isowbuf_donewrite(iwb);
 		}
@@ -233,7 +234,7 @@ int gigaset_isowbuf_getbytes(struct isowbuf_t *iwb, int size)
 			limit = src;
 		}
 	}
-	atomic_set(&iwb->nextread, limit);
+	iwb->nextread = limit;
 	return read;
 }
 
@@ -477,7 +478,7 @@ static inline int trans_buildframe(struct isowbuf_t *iwb,
 	unsigned char c;
 
 	if (unlikely(count <= 0))
-		return atomic_read(&iwb->write); /* better ideas? */
+		return iwb->write;
 
 	if (isowbuf_freebytes(iwb) < count ||
 	    !isowbuf_startwrite(iwb)) {
@@ -486,13 +487,13 @@ static inline int trans_buildframe(struct isowbuf_t *iwb,
 	}
 
 	gig_dbg(DEBUG_STREAM, "put %d bytes", count);
-	write = atomic_read(&iwb->write);
+	write = iwb->write;
 	do {
 		c = bitrev8(*in++);
 		iwb->data[write++] = c;
 		write %= BAS_OUTBUFSIZE;
 	} while (--count > 0);
-	atomic_set(&iwb->write, write);
+	iwb->write = write;
 	iwb->idle = c;
 
 	return isowbuf_donewrite(iwb);
@@ -947,8 +948,8 @@ void gigaset_isoc_input(struct inbuf_t *inbuf)
 	unsigned tail, head, numbytes;
 	unsigned char *src;
 
-	head = atomic_read(&inbuf->head);
-	while (head != (tail = atomic_read(&inbuf->tail))) {
+	head = inbuf->head;
+	while (head != (tail = inbuf->tail)) {
 		gig_dbg(DEBUG_INTR, "buffer state: %u -> %u", head, tail);
 		if (head > tail)
 			tail = RBUFSIZE;
@@ -956,7 +957,7 @@ void gigaset_isoc_input(struct inbuf_t *inbuf)
 		numbytes = tail - head;
 		gig_dbg(DEBUG_INTR, "processing %u bytes", numbytes);
 
-		if (atomic_read(&cs->mstate) == MS_LOCKED) {
+		if (cs->mstate == MS_LOCKED) {
 			gigaset_dbg_buffer(DEBUG_LOCKCMD, "received response",
 					   numbytes, src);
 			gigaset_if_receive(inbuf->cs, src, numbytes);
@@ -970,7 +971,7 @@ void gigaset_isoc_input(struct inbuf_t *inbuf)
 		if (head == RBUFSIZE)
 			head = 0;
 		gig_dbg(DEBUG_INTR, "setting head to %u", head);
-		atomic_set(&inbuf->head, head);
+		inbuf->head = head;
 	}
 }
 

drivers/isdn/gigaset/ser-gigaset.c

@@ -240,7 +240,7 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
 	struct cmdbuf_t *cb;
 	unsigned long flags;
 
-	gigaset_dbg_buffer(atomic_read(&cs->mstate) != MS_LOCKED ?
+	gigaset_dbg_buffer(cs->mstate != MS_LOCKED ?
 	                     DEBUG_TRANSCMD : DEBUG_LOCKCMD,
 	                   "CMD Transmit", len, buf);
 
@@ -536,7 +536,7 @@ gigaset_tty_open(struct tty_struct *tty)
 	 * startup system and notify the LL that we are ready to run
 	 */
 	if (startmode == SM_LOCKED)
-		atomic_set(&cs->mstate, MS_LOCKED);
+		cs->mstate = MS_LOCKED;
 	if (!gigaset_start(cs)) {
 		tasklet_kill(&cs->write_tasklet);
 		goto error;
@@ -714,8 +714,8 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf,
 		return;
 	}
 
-	tail = atomic_read(&inbuf->tail);
-	head = atomic_read(&inbuf->head);
+	tail = inbuf->tail;
+	head = inbuf->head;
 	gig_dbg(DEBUG_INTR, "buffer state: %u -> %u, receive %u bytes",
 		head, tail, count);
 
@@ -742,7 +742,7 @@ gigaset_tty_receive(struct tty_struct *tty, const unsigned char *buf,
 	}
 
 	gig_dbg(DEBUG_INTR, "setting tail to %u", tail);
-	atomic_set(&inbuf->tail, tail);
+	inbuf->tail = tail;
 
 	/* Everything was received .. Push data into handler */
 	gig_dbg(DEBUG_INTR, "%s-->BH", __func__);

drivers/isdn/gigaset/usb-gigaset.c

@@ -133,7 +133,7 @@ static struct usb_driver gigaset_usb_driver = {
 struct usb_cardstate {
 	struct usb_device	*udev;		/* usb device pointer */
 	struct usb_interface	*interface;	/* interface for this device */
-	atomic_t		busy;		/* bulk output in progress */
+	int			busy;		/* bulk output in progress */
 
 	/* Output buffer */
 	unsigned char		*bulk_out_buffer;
@@ -325,7 +325,7 @@ static void gigaset_modem_fill(unsigned long data)
 
 	gig_dbg(DEBUG_OUTPUT, "modem_fill");
 
-	if (atomic_read(&cs->hw.usb->busy)) {
+	if (cs->hw.usb->busy) {
 		gig_dbg(DEBUG_OUTPUT, "modem_fill: busy");
 		return;
 	}
@@ -430,7 +430,7 @@ static void gigaset_write_bulk_callback(struct urb *urb)
 		break;
 	case -ENOENT:		/* killed */
 		gig_dbg(DEBUG_ANY, "%s: killed", __func__);
-		atomic_set(&cs->hw.usb->busy, 0);
+		cs->hw.usb->busy = 0;
 		return;
 	default:
 		dev_err(cs->dev, "bulk transfer failed (status %d)\n",
@@ -443,7 +443,7 @@ static void gigaset_write_bulk_callback(struct urb *urb)
 	if (!cs->connected) {
 		err("%s: not connected", __func__);
 	} else {
-		atomic_set(&cs->hw.usb->busy, 0);
+		cs->hw.usb->busy = 0;
 		tasklet_schedule(&cs->write_tasklet);
 	}
 	spin_unlock_irqrestore(&cs->lock, flags);
@@ -491,14 +491,14 @@ static int send_cb(struct cardstate *cs, struct cmdbuf_t *cb)
 
 			cb->offset += count;
 			cb->len -= count;
-			atomic_set(&ucs->busy, 1);
+			ucs->busy = 1;
 
 			spin_lock_irqsave(&cs->lock, flags);
 			status = cs->connected ? usb_submit_urb(ucs->bulk_out_urb, GFP_ATOMIC) : -ENODEV;
 			spin_unlock_irqrestore(&cs->lock, flags);
 
 			if (status) {
-				atomic_set(&ucs->busy, 0);
+				ucs->busy = 0;
 				err("could not submit urb (error %d)\n",
 				    -status);
 				cb->len = 0; /* skip urb => remove cb+wakeup
@@ -517,7 +517,7 @@ static int gigaset_write_cmd(struct cardstate *cs, const unsigned char *buf,
 	struct cmdbuf_t *cb;
 	unsigned long flags;
 
-	gigaset_dbg_buffer(atomic_read(&cs->mstate) != MS_LOCKED ?
+	gigaset_dbg_buffer(cs->mstate != MS_LOCKED ?
 			     DEBUG_TRANSCMD : DEBUG_LOCKCMD,
 			   "CMD Transmit", len, buf);
 
@@ -654,7 +654,7 @@ static int write_modem(struct cardstate *cs)
 	count = min(bcs->tx_skb->len, (unsigned) ucs->bulk_out_size);
 	skb_copy_from_linear_data(bcs->tx_skb, ucs->bulk_out_buffer, count);
 	skb_pull(bcs->tx_skb, count);
-	atomic_set(&ucs->busy, 1);
+	ucs->busy = 1;
 	gig_dbg(DEBUG_OUTPUT, "write_modem: send %d bytes", count);
 
 	spin_lock_irqsave(&cs->lock, flags);
@@ -672,7 +672,7 @@ static int write_modem(struct cardstate *cs)
 
 	if (ret) {
 		err("could not submit urb (error %d)\n", -ret);
-		atomic_set(&ucs->busy, 0);
+		ucs->busy = 0;
 	}
 
 	if (!bcs->tx_skb->len) {
@@ -764,7 +764,7 @@ static int gigaset_probe(struct usb_interface *interface,
 
 	endpoint = &hostif->endpoint[1].desc;
 
-	atomic_set(&ucs->busy, 0);
+	ucs->busy = 0;
 
 	ucs->read_urb = usb_alloc_urb(0, GFP_KERNEL);
 	if (!ucs->read_urb) {
@@ -797,7 +797,7 @@ static int gigaset_probe(struct usb_interface *interface,
 
 	/* tell common part that the device is ready */
 	if (startmode == SM_LOCKED)
-		atomic_set(&cs->mstate, MS_LOCKED);
+		cs->mstate = MS_LOCKED;
 
 	if (!gigaset_start(cs)) {
 		tasklet_kill(&cs->write_tasklet);