Re: [PATCH v1] misc: fastrpc: Add support for multiple PD from one process

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On 7/3/2024 4:12 PM, Dmitry Baryshkov wrote:
> On Wed, Jul 03, 2024 at 12:22:00PM GMT, Ekansh Gupta wrote:
>> Memory intensive applications(which requires more tha 4GB) that wants
>> to offload tasks to DSP might have to split the tasks to multiple
>> user PD to make the resources available. For every call to DSP,
>> fastrpc driver passes the process tgid which works as an identifier
>> for the DSP to enqueue the tasks to specific PD. With current design,
>> if any process opens device node more than once and makes PD init
>> request, same tgid will be passed to DSP which will be considered a
>> bad request and this will result in failure as the same identifier
>> cannot be used for multiple DSP PD. Allocate and pass an effective
>> pgid to DSP which would be allocated during device open and will have
>> a lifetime till the device is closed. This will allow the same process
>> to open the device more than once and spawn multiple dynamic PD for
>> ease of processing.
> Consider adding line breaks to split the text into paragraphs to make it
> easier to read.
>
> The patch also raises the question whether the identifier should be
> unique per DSP or per the channel.
I'll update the commit text with more clear information.
>> Signed-off-by: Ekansh Gupta <quic_ekangupt@xxxxxxxxxxx>
>> ---
>>  drivers/misc/fastrpc.c | 48 ++++++++++++++++++++++++++++++++++--------
>>  1 file changed, 39 insertions(+), 9 deletions(-)
>>
>> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
>> index 5204fda51da3..7250e30aa93f 100644
>> --- a/drivers/misc/fastrpc.c
>> +++ b/drivers/misc/fastrpc.c
>> @@ -105,6 +105,10 @@
>>  
>>  #define miscdev_to_fdevice(d) container_of(d, struct fastrpc_device, miscdev)
>>  
>> +#define MAX_DSP_PD	64
>> +#define MIN_FRPC_PGID	1000
>> +#define MAX_FRPC_PGID	(MIN_FRPC_PGID + MAX_DSP_PD)
>> +
>>  static const char *domains[FASTRPC_DEV_MAX] = { "adsp", "mdsp",
>>  						"sdsp", "cdsp"};
>>  struct fastrpc_phy_page {
>> @@ -268,6 +272,7 @@ struct fastrpc_channel_ctx {
>>  	struct fastrpc_session_ctx session[FASTRPC_MAX_SESSIONS];
>>  	spinlock_t lock;
>>  	struct idr ctx_idr;
>> +	struct ida dsp_pgid_ida;
>>  	struct list_head users;
>>  	struct kref refcount;
>>  	/* Flag if dsp attributes are cached */
>> @@ -299,6 +304,7 @@ struct fastrpc_user {
>>  	struct fastrpc_buf *init_mem;
>>  
>>  	int tgid;
> Is it still used? What for?
I don't see any usage as of now, this can be removed.
>
>> +	int dsp_pgid;
> unsigned int
planning to keep it u32 as the range is going to be from 1000-1064
>
>>  	int pd;
>>  	bool is_secure_dev;
>>  	/* Lock for lists */
>> @@ -462,6 +468,7 @@ static void fastrpc_channel_ctx_free(struct kref *ref)
>>  	struct fastrpc_channel_ctx *cctx;
>>  
>>  	cctx = container_of(ref, struct fastrpc_channel_ctx, refcount);
>> +	ida_destroy(&cctx->dsp_pgid_ida);
>>  
>>  	kfree(cctx);
>>  }
>> @@ -1114,7 +1121,7 @@ static int fastrpc_invoke_send(struct fastrpc_session_ctx *sctx,
>>  	int ret;
>>  
>>  	cctx = fl->cctx;
>> -	msg->pid = fl->tgid;
>> +	msg->pid = fl->dsp_pgid;
>>  	msg->tid = current->pid;
>>  
>>  	if (kernel)
>> @@ -1292,7 +1299,7 @@ static int fastrpc_init_create_static_process(struct fastrpc_user *fl,
>>  		}
>>  	}
>>  
>> -	inbuf.pgid = fl->tgid;
>> +	inbuf.pgid = fl->dsp_pgid;
>>  	inbuf.namelen = init.namelen;
>>  	inbuf.pageslen = 0;
>>  	fl->pd = USER_PD;
>> @@ -1394,7 +1401,7 @@ static int fastrpc_init_create_process(struct fastrpc_user *fl,
>>  		goto err;
>>  	}
>>  
>> -	inbuf.pgid = fl->tgid;
>> +	inbuf.pgid = fl->dsp_pgid;
>>  	inbuf.namelen = strlen(current->comm) + 1;
>>  	inbuf.filelen = init.filelen;
>>  	inbuf.pageslen = 1;
>> @@ -1503,7 +1510,7 @@ static int fastrpc_release_current_dsp_process(struct fastrpc_user *fl)
>>  	int tgid = 0;
>>  	u32 sc;
>>  
>> -	tgid = fl->tgid;
>> +	tgid = fl->dsp_pgid;
>>  	args[0].ptr = (u64)(uintptr_t) &tgid;
>>  	args[0].length = sizeof(tgid);
>>  	args[0].fd = -1;
>> @@ -1528,6 +1535,9 @@ static int fastrpc_device_release(struct inode *inode, struct file *file)
>>  	list_del(&fl->user);
>>  	spin_unlock_irqrestore(&cctx->lock, flags);
>>  
>> +	if (fl->dsp_pgid != -1)
> Why -1? On which path can it be left uninitialized?
in case ida allocation fails, I was setting this to -1 but now I don't see any reason for
this check as if ida alloc fails, that will result in open() failure.
>
>> +		ida_free(&cctx->dsp_pgid_ida, fl->dsp_pgid);
>> +
>>  	if (fl->init_mem)
>>  		fastrpc_buf_free(fl->init_mem);
>>  
>> @@ -1554,6 +1564,19 @@ static int fastrpc_device_release(struct inode *inode, struct file *file)
>>  	return 0;
>>  }
>>  
>> +static int fastrpc_pgid_alloc(struct fastrpc_channel_ctx *cctx)
>> +{
>> +	int ret = -1;
> There is no need to init it, is there?
no, I'll remove this.
>
>> +
>> +	/* allocate unique id between MIN_FRPC_PGID and MAX_FRPC_PGID */
>> +	ret = ida_alloc_range(&cctx->dsp_pgid_ida, MIN_FRPC_PGID,
>> +					MAX_FRPC_PGID, GFP_ATOMIC);
>> +	if (ret < 0)
>> +		return -1;
> Don't throw away error codes. Pass them as is.
Ack.
>
>> +
>> +	return ret;
>> +}
>> +
>>  static int fastrpc_device_open(struct inode *inode, struct file *filp)
>>  {
>>  	struct fastrpc_channel_ctx *cctx;
>> @@ -1582,6 +1605,12 @@ static int fastrpc_device_open(struct inode *inode, struct file *filp)
>>  	fl->cctx = cctx;
>>  	fl->is_secure_dev = fdevice->secure;
>>  
>> +	fl->dsp_pgid = fastrpc_pgid_alloc(cctx);
>> +	if (fl->dsp_pgid == -1) {
>> +		dev_dbg(&cctx->rpdev->dev, "too many fastrpc clients, max %u allowed\n", MAX_DSP_PD);
>> +		return -EUSERS;
> Huh? Please return the error code that ida_alloc() returned;
Ack.
>
>> +	}
>> +
>>  	fl->sctx = fastrpc_session_alloc(cctx);
>>  	if (!fl->sctx) {
>>  		dev_err(&cctx->rpdev->dev, "No session available\n");
>> @@ -1646,7 +1675,7 @@ static int fastrpc_dmabuf_alloc(struct fastrpc_user *fl, char __user *argp)
>>  static int fastrpc_init_attach(struct fastrpc_user *fl, int pd)
>>  {
>>  	struct fastrpc_invoke_args args[1];
>> -	int tgid = fl->tgid;
>> +	int tgid = fl->dsp_pgid;
> unsigned?
will update this. Thanks.

--Ekansh
>
>>  	u32 sc;
>>  
>>  	args[0].ptr = (u64)(uintptr_t) &tgid;
>> @@ -1802,7 +1831,7 @@ static int fastrpc_req_munmap_impl(struct fastrpc_user *fl, struct fastrpc_buf *
>>  	int err;
>>  	u32 sc;
>>  
>> -	req_msg.pgid = fl->tgid;
>> +	req_msg.pgid = fl->dsp_pgid;
>>  	req_msg.size = buf->size;
>>  	req_msg.vaddr = buf->raddr;
>>  
>> @@ -1888,7 +1917,7 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl, char __user *argp)
>>  		return err;
>>  	}
>>  
>> -	req_msg.pgid = fl->tgid;
>> +	req_msg.pgid = fl->dsp_pgid;
>>  	req_msg.flags = req.flags;
>>  	req_msg.vaddr = req.vaddrin;
>>  	req_msg.num = sizeof(pages);
>> @@ -1978,7 +2007,7 @@ static int fastrpc_req_mem_unmap_impl(struct fastrpc_user *fl, struct fastrpc_me
>>  		return -EINVAL;
>>  	}
>>  
>> -	req_msg.pgid = fl->tgid;
>> +	req_msg.pgid = fl->dsp_pgid;
>>  	req_msg.len = map->len;
>>  	req_msg.vaddrin = map->raddr;
>>  	req_msg.fd = map->fd;
>> @@ -2031,7 +2060,7 @@ static int fastrpc_req_mem_map(struct fastrpc_user *fl, char __user *argp)
>>  		return err;
>>  	}
>>  
>> -	req_msg.pgid = fl->tgid;
>> +	req_msg.pgid = fl->dsp_pgid;
>>  	req_msg.fd = req.fd;
>>  	req_msg.offset = req.offset;
>>  	req_msg.vaddrin = req.vaddrin;
>> @@ -2375,6 +2404,7 @@ static int fastrpc_rpmsg_probe(struct rpmsg_device *rpdev)
>>  	INIT_LIST_HEAD(&data->invoke_interrupted_mmaps);
>>  	spin_lock_init(&data->lock);
>>  	idr_init(&data->ctx_idr);
>> +	ida_init(&data->dsp_pgid_ida);
>>  	data->domain_id = domain_id;
>>  	data->rpdev = rpdev;
>>  
>> -- 
>> 2.34.1
>>




[Index of Archives]     [Linux DRI Users]     [Linux Intel Graphics]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite News]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]
  Powered by Linux