[PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[Andy Shevchenko]

Some of the existing users, and definitely will be new ones, want to
count existing nodes in the list. Provide a generic API for that by
moving code from i915 to list.h.

Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v5: added tag (Lucas), renamed API to list_count_nodes() (LKP)
v4: fixed prototype when converting to static inline
v3: added tag (Jani), changed to be static inline (Mike)
v2: dropped the duplicate code in i915 (LKP)
 drivers/gpu/drm/i915/gt/intel_engine_cs.c | 15 ++-------------
 include/linux/list.h                      | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/gt/intel_engine_cs.c b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
index 1f7188129cd1..370164363b0d 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -2004,17 +2004,6 @@ static void print_request_ring(struct drm_printer *m, struct i915_request *rq)
 	}
 }
 
-static unsigned long list_count(struct list_head *list)
-{
-	struct list_head *pos;
-	unsigned long count = 0;
-
-	list_for_each(pos, list)
-		count++;
-
-	return count;
-}
-
 static unsigned long read_ul(void *p, size_t x)
 {
 	return *(unsigned long *)(p + x);
@@ -2189,8 +2178,8 @@ void intel_engine_dump(struct intel_engine_cs *engine,
 	spin_lock_irqsave(&engine->sched_engine->lock, flags);
 	engine_dump_active_requests(engine, m);
 
-	drm_printf(m, "\tOn hold?: %lu\n",
-		   list_count(&engine->sched_engine->hold));
+	drm_printf(m, "\tOn hold?: %zu\n",
+		   list_count_nodes(&engine->sched_engine->hold));
 	spin_unlock_irqrestore(&engine->sched_engine->lock, flags);
 
 	drm_printf(m, "\tMMIO base:  0x%08x\n", engine->mmio_base);
diff --git a/include/linux/list.h b/include/linux/list.h
index 61762054b4be..f10344dbad4d 100644
--- a/include/linux/list.h
+++ b/include/linux/list.h
@@ -655,6 +655,21 @@ static inline void list_splice_tail_init(struct list_head *list,
 	     !list_is_head(pos, (head)); \
 	     pos = n, n = pos->prev)
 
+/**
+ * list_count_nodes - count nodes in the list
+ * @head:	the head for your list.
+ */
+static inline size_t list_count_nodes(struct list_head *head)
+{
+	struct list_head *pos;
+	size_t count = 0;
+
+	list_for_each(pos, head)
+		count++;
+
+	return count;
+}
+
 /**
  * list_entry_is_head - test if the entry points to the head of the list
  * @pos:	the type * to cursor
-- 
2.35.1

[PATCH v5 2/4] usb: gadget: hid: Convert to use list_count_nodes()

[Andy Shevchenko]

The list API provides the list_count_nodes() to help with counting
existing nodes in the list. Utilise it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v5: used renamed API (LKP)
v4: no change
v3: fixed typo in the commit message (Fabio)                                                                     
v2: no change
 drivers/usb/gadget/legacy/hid.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/gadget/legacy/hid.c b/drivers/usb/gadget/legacy/hid.c
index 1187ee4f316a..133daf88162e 100644
--- a/drivers/usb/gadget/legacy/hid.c
+++ b/drivers/usb/gadget/legacy/hid.c
@@ -133,14 +133,11 @@ static struct usb_configuration config_driver = {
 static int hid_bind(struct usb_composite_dev *cdev)
 {
 	struct usb_gadget *gadget = cdev->gadget;
-	struct list_head *tmp;
 	struct hidg_func_node *n = NULL, *m, *iter_n;
 	struct f_hid_opts *hid_opts;
-	int status, funcs = 0;
-
-	list_for_each(tmp, &hidg_func_list)
-		funcs++;
+	int status, funcs;
 
+	funcs = list_count_nodes(&hidg_func_list);
 	if (!funcs)
 		return -ENODEV;
 
-- 
2.35.1

[PATCH v5 3/4] usb: gadget: udc: bcm63xx: Convert to use list_count_nodes()

[Andy Shevchenko]

The list API provides the list_count_nodes() to help with counting
existing nodes in the list. Utilise it.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v5: used renamed API (LKP)
v4: no change
v3: no change
v2: no change
 drivers/usb/gadget/udc/bcm63xx_udc.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/drivers/usb/gadget/udc/bcm63xx_udc.c b/drivers/usb/gadget/udc/bcm63xx_udc.c
index 2cdb07905bde..771ba1ffce95 100644
--- a/drivers/usb/gadget/udc/bcm63xx_udc.c
+++ b/drivers/usb/gadget/udc/bcm63xx_udc.c
@@ -2172,7 +2172,6 @@ static int bcm63xx_iudma_dbg_show(struct seq_file *s, void *p)
 
 	for (ch_idx = 0; ch_idx < BCM63XX_NUM_IUDMA; ch_idx++) {
 		struct iudma_ch *iudma = &udc->iudma[ch_idx];
-		struct list_head *pos;
 
 		seq_printf(s, "IUDMA channel %d -- ", ch_idx);
 		switch (iudma_defaults[ch_idx].ep_type) {
@@ -2205,14 +2204,10 @@ static int bcm63xx_iudma_dbg_show(struct seq_file *s, void *p)
 		seq_printf(s, "  desc: %d/%d used", iudma->n_bds_used,
 			   iudma->n_bds);
 
-		if (iudma->bep) {
-			i = 0;
-			list_for_each(pos, &iudma->bep->queue)
-				i++;
-			seq_printf(s, "; %d queued\n", i);
-		} else {
+		if (iudma->bep)
+			seq_printf(s, "; %zu queued\n", list_count_nodes(&iudma->bep->queue));
+		else
 			seq_printf(s, "\n");
-		}
 
 		for (i = 0; i < iudma->n_bds; i++) {
 			struct bcm_enet_desc *d = &iudma->bd_ring[i];
-- 
2.35.1

[PATCH v5 4/4] xhci: Convert to use list_count_nodes()

[Andy Shevchenko]

The list API provides the list_count_nodes() to help with counting
existing nodes in the list. Utilise it.

Acked-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v5: used renamed API (LKP)
v4: added tag (Mathias)
v3: no change
v2: no change
 drivers/usb/host/xhci-ring.c | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index ddc30037f9ce..aa4d34efecd2 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -2528,7 +2528,6 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 	union xhci_trb *ep_trb;
 	int status = -EINPROGRESS;
 	struct xhci_ep_ctx *ep_ctx;
-	struct list_head *tmp;
 	u32 trb_comp_code;
 	int td_num = 0;
 	bool handling_skipped_tds = false;
@@ -2582,10 +2581,8 @@ static int handle_tx_event(struct xhci_hcd *xhci,
 	}
 
 	/* Count current td numbers if ep->skip is set */
-	if (ep->skip) {
-		list_for_each(tmp, &ep_ring->td_list)
-			td_num++;
-	}
+	if (ep->skip)
+		td_num += list_count_nodes(&ep_ring->td_list);
 
 	/* Look for common error cases */
 	switch (trb_comp_code) {
-- 
2.35.1

Re: [PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[Andy Shevchenko]

On Wed, Nov 30, 2022 at 03:48:35PM +0200, Andy Shevchenko wrote:
> Some of the existing users, and definitely will be new ones, want to
> count existing nodes in the list. Provide a generic API for that by
> moving code from i915 to list.h.

Greg, I believe this one is ready to be taken. Or please tell me what I need
to do.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[Greg Kroah-Hartman]

On Thu, Dec 08, 2022 at 02:54:45PM +0200, Andy Shevchenko wrote:
> On Wed, Nov 30, 2022 at 03:48:35PM +0200, Andy Shevchenko wrote:
> > Some of the existing users, and definitely will be new ones, want to
> > count existing nodes in the list. Provide a generic API for that by
> > moving code from i915 to list.h.
> 
> Greg, I believe this one is ready to be taken. Or please tell me what I need
> to do.

Wait for me to get through the current backlog of patches that I have in
my review queue.  Odds are, it will have to wait until after 6.2-rc1 is
out based on when 6.1 is going to be released.

Don't worry, it's not lost.

thanks,

greg k-h

Re: [PATCH v5 1/4] i915: Move list_count() to list.h as list_count_nodes() for broader use

[Andy Shevchenko]

On Thu, Dec 08, 2022 at 02:14:54PM +0100, Greg Kroah-Hartman wrote:
> On Thu, Dec 08, 2022 at 02:54:45PM +0200, Andy Shevchenko wrote:
> > On Wed, Nov 30, 2022 at 03:48:35PM +0200, Andy Shevchenko wrote:
> > > Some of the existing users, and definitely will be new ones, want to
> > > count existing nodes in the list. Provide a generic API for that by
> > > moving code from i915 to list.h.
> > 
> > Greg, I believe this one is ready to be taken. Or please tell me what I need
> > to do.
> 
> Wait for me to get through the current backlog of patches that I have in
> my review queue.  Odds are, it will have to wait until after 6.2-rc1 is
> out based on when 6.1 is going to be released.

It's fine, no hurry and take your time!

> Don't worry, it's not lost.

Thank you, got it!

-- 
With Best Regards,
Andy Shevchenko