Linux kernel staging patches
 help / color / mirror / Atom feed
From: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
To: Umang Jain <umang.jain@ideasonboard.com>
Cc: linux-staging@lists.linux.dev, Dan Carpenter <error27@gmail.com>,
	Kieran Bingham <kieran.bingham@ideasonboard.com>,
	Dave Stevenson <dave.stevenson@raspberrypi.com>,
	Phil Elwell <phil@raspberrypi.com>, Greg KH <greg@kroah.com>,
	Stefan Wahren <wahrenst@gmx.net>
Subject: Re: [PATCH v4 06/11] staging: vc04_services: Move global variables tracking allocated pages
Date: Fri, 29 Mar 2024 01:04:08 +0200	[thread overview]
Message-ID: <20240328230408.GN11463@pendragon.ideasonboard.com> (raw)
In-Reply-To: <20240328225958.GK11463@pendragon.ideasonboard.com>

On Fri, Mar 29, 2024 at 12:59:59AM +0200, Laurent Pinchart wrote:
> Hi Umang,
> 
> Thank you for the patch.
> 
> On Thu, Mar 28, 2024 at 11:41:28PM +0530, Umang Jain wrote:
> > The variables tracking allocated pages fragments in vchiq_arm.c
> > can be easily moved to struct vchiq_drv_mgmt instead of being global.
> > This helps us to drop the non-essential global variables in the vchiq
> > interface.
> > 
> > No functional changes intended in this patch.
> > 
> > Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
> 
> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
> 
> > ---
> >  .../interface/vchiq_arm/vchiq_arm.c           | 53 +++++++++----------
> >  .../interface/vchiq_arm/vchiq_arm.h           |  6 +++
> >  2 files changed, 30 insertions(+), 29 deletions(-)
> > 
> > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > index 2005d392d0b7..b335948f4b0c 100644
> > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> > @@ -130,12 +130,6 @@ struct vchiq_pagelist_info {
> >  };
> >  
> >  static void __iomem *g_regs;
> > -static unsigned int g_fragments_size;
> > -static char *g_fragments_base;
> > -static char *g_free_fragments;
> > -static struct semaphore g_free_fragments_sema;
> > -
> > -static DEFINE_SEMAPHORE(g_free_fragments_mutex, 1);
> >  
> >  static int
> >  vchiq_blocking_bulk_transfer(struct vchiq_instance *instance, unsigned int handle, void *data,
> > @@ -414,20 +408,20 @@ create_pagelist(struct vchiq_instance *instance, char *buf, char __user *ubuf,
> >  	    (drv_mgmt->info->cache_line_size - 1)))) {
> >  		char *fragments;
> >  
> > -		if (down_interruptible(&g_free_fragments_sema)) {
> > +		if (down_interruptible(&drv_mgmt->free_fragments_sema)) {
> >  			cleanup_pagelistinfo(instance, pagelistinfo);
> >  			return NULL;
> >  		}
> >  
> > -		WARN_ON(!g_free_fragments);
> > +		WARN_ON(!drv_mgmt->free_fragments);
> >  
> > -		down(&g_free_fragments_mutex);
> > -		fragments = g_free_fragments;
> > +		down(&drv_mgmt->free_fragments_mutex);
> > +		fragments = drv_mgmt->free_fragments;
> >  		WARN_ON(!fragments);
> > -		g_free_fragments = *(char **)g_free_fragments;
> > -		up(&g_free_fragments_mutex);
> > +		drv_mgmt->free_fragments = *(char **)drv_mgmt->free_fragments;
> > +		up(&drv_mgmt->free_fragments_mutex);
> >  		pagelist->type = PAGELIST_READ_WITH_FRAGMENTS +
> > -			(fragments - g_fragments_base) / g_fragments_size;
> > +			(fragments - drv_mgmt->fragments_base) / drv_mgmt->fragments_size;
> >  	}
> >  
> >  	return pagelistinfo;
> > @@ -455,10 +449,10 @@ free_pagelist(struct vchiq_instance *instance, struct vchiq_pagelist_info *pagel
> >  	pagelistinfo->scatterlist_mapped = 0;
> >  
> >  	/* Deal with any partial cache lines (fragments) */
> > -	if (pagelist->type >= PAGELIST_READ_WITH_FRAGMENTS && g_fragments_base) {
> > -		char *fragments = g_fragments_base +
> > +	if (pagelist->type >= PAGELIST_READ_WITH_FRAGMENTS && drv_mgmt->fragments_base) {
> > +		char *fragments = drv_mgmt->fragments_base +
> >  			(pagelist->type - PAGELIST_READ_WITH_FRAGMENTS) *
> > -			g_fragments_size;
> > +			drv_mgmt->fragments_size;
> >  		int head_bytes, tail_bytes;
> >  
> >  		head_bytes = (drv_mgmt->info->cache_line_size - pagelist->offset) &
> > @@ -483,11 +477,11 @@ free_pagelist(struct vchiq_instance *instance, struct vchiq_pagelist_info *pagel
> >  				fragments + drv_mgmt->info->cache_line_size,
> >  				tail_bytes);
> >  
> > -		down(&g_free_fragments_mutex);
> > -		*(char **)fragments = g_free_fragments;
> > -		g_free_fragments = fragments;
> > -		up(&g_free_fragments_mutex);
> > -		up(&g_free_fragments_sema);
> > +		down(&drv_mgmt->free_fragments_mutex);
> > +		*(char **)fragments = drv_mgmt->free_fragments;
> > +		drv_mgmt->free_fragments = fragments;
> > +		up(&drv_mgmt->free_fragments_mutex);
> > +		up(&drv_mgmt->free_fragments_sema);
> >  	}
> >  
> >  	/* Need to mark all the pages dirty. */
> > @@ -523,11 +517,11 @@ static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state
> >  	if (err < 0)
> >  		return err;
> >  
> > -	g_fragments_size = 2 * drv_mgmt->info->cache_line_size;
> > +	drv_mgmt->fragments_size = 2 * drv_mgmt->info->cache_line_size;
> >  
> >  	/* Allocate space for the channels in coherent memory */
> >  	slot_mem_size = PAGE_ALIGN(TOTAL_SLOTS * VCHIQ_SLOT_SIZE);
> > -	frag_mem_size = PAGE_ALIGN(g_fragments_size * MAX_FRAGMENTS);
> > +	frag_mem_size = PAGE_ALIGN(drv_mgmt->fragments_size * MAX_FRAGMENTS);
> >  
> >  	slot_mem = dmam_alloc_coherent(dev, slot_mem_size + frag_mem_size,
> >  				       &slot_phys, GFP_KERNEL);
> > @@ -547,15 +541,16 @@ static int vchiq_platform_init(struct platform_device *pdev, struct vchiq_state
> >  	vchiq_slot_zero->platform_data[VCHIQ_PLATFORM_FRAGMENTS_COUNT_IDX] =
> >  		MAX_FRAGMENTS;
> >  
> > -	g_fragments_base = (char *)slot_mem + slot_mem_size;
> > +	drv_mgmt->fragments_base = (char *)slot_mem + slot_mem_size;
> >  
> > -	g_free_fragments = g_fragments_base;
> > +	drv_mgmt->free_fragments = drv_mgmt->fragments_base;
> >  	for (i = 0; i < (MAX_FRAGMENTS - 1); i++) {
> > -		*(char **)&g_fragments_base[i * g_fragments_size] =
> > -			&g_fragments_base[(i + 1) * g_fragments_size];
> > +		*(char **)&drv_mgmt->fragments_base[i * drv_mgmt->fragments_size] =
> > +			&drv_mgmt->fragments_base[(i + 1) * drv_mgmt->fragments_size];
> >  	}
> > -	*(char **)&g_fragments_base[i * g_fragments_size] = NULL;
> > -	sema_init(&g_free_fragments_sema, MAX_FRAGMENTS);
> > +	*(char **)&drv_mgmt->fragments_base[i * drv_mgmt->fragments_size] = NULL;
> > +	sema_init(&drv_mgmt->free_fragments_sema, MAX_FRAGMENTS);
> > +	sema_init(&drv_mgmt->free_fragments_mutex, 1);
> >  
> >  	err = vchiq_init_state(state, vchiq_slot_zero, dev);
> >  	if (err)
> > diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > index 4a5b5ae9625a..a3bba245bfe2 100644
> > --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.h
> > @@ -59,6 +59,12 @@ struct vchiq_drv_mgmt {
> >  	struct mutex connected_mutex;
> >  
> >  	void (*deferred_callback[VCHIQ_DRV_MAX_CALLBACKS])(void);
> > +
> > +	struct semaphore free_fragments_sema;
> > +	struct semaphore free_fragments_mutex;

Could we turn the latter into a mutex (in a separate patch) ?

> > +	char *fragments_base;
> > +	char *free_fragments;
> > +	unsigned int fragments_size;
> >  };
> >  
> >  struct user_service {

-- 
Regards,

Laurent Pinchart

  reply	other threads:[~2024-03-28 23:04 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2024-03-28 18:11 [PATCH v4 00/11] staging: vc04_services: Drop non-essential global members Umang Jain
2024-03-28 18:11 ` [PATCH v4 01/11] staging: vc04_services: Drop g_once_init global variable Umang Jain
2024-03-28 18:11 ` [PATCH v4 02/11] staging: vc04_services: vchiq_arm: Split driver static and runtime data Umang Jain
2024-03-28 22:33   ` Laurent Pinchart
2024-03-28 18:11 ` [PATCH v4 03/11] staging: vc04_services: vchiq_arm: Drop g_cache_line_size Umang Jain
2024-03-28 18:11 ` [PATCH v4 04/11] staging: vc04_services: Move variables for tracking connections Umang Jain
2024-03-28 22:38   ` Laurent Pinchart
2024-03-28 18:11 ` [PATCH v4 05/11] staging: vc04_services: Drop vchiq_connected.[ch] files Umang Jain
2024-03-28 22:52   ` Laurent Pinchart
2024-03-28 18:11 ` [PATCH v4 06/11] staging: vc04_services: Move global variables tracking allocated pages Umang Jain
2024-03-28 22:59   ` Laurent Pinchart
2024-03-28 23:04     ` Laurent Pinchart [this message]
2024-04-01  5:00       ` Umang Jain
2024-03-28 18:11 ` [PATCH v4 07/11] staging: vc04_services: Move global memory mapped pointer Umang Jain
2024-03-28 23:01   ` Laurent Pinchart
2024-03-28 18:11 ` [PATCH v4 08/11] staging: vc04_services: Move spinlocks to vchiq_state Umang Jain
2024-03-28 18:11 ` [PATCH v4 09/11] staging: vc04_services: vchiq_mmal: Rename service_callback() Umang Jain
2024-03-28 23:03   ` Laurent Pinchart
2024-03-28 18:11 ` [PATCH v4 10/11] staging: vc04_services: Move global g_state vchiq_state pointer Umang Jain
2024-03-28 18:11 ` [PATCH v4 11/11] staging: vc04_services: Drop completed TODO item Umang Jain
2024-04-09 15:46 ` [PATCH v4 00/11] staging: vc04_services: Drop non-essential global members Greg KH

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20240328230408.GN11463@pendragon.ideasonboard.com \
    --to=laurent.pinchart@ideasonboard.com \
    --cc=dave.stevenson@raspberrypi.com \
    --cc=error27@gmail.com \
    --cc=greg@kroah.com \
    --cc=kieran.bingham@ideasonboard.com \
    --cc=linux-staging@lists.linux.dev \
    --cc=phil@raspberrypi.com \
    --cc=umang.jain@ideasonboard.com \
    --cc=wahrenst@gmx.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).