[PATCH v2 0/5] USB: Gadget SuperSpeed fixes and a cleanup

[PATCH v2 0/5] USB: Gadget SuperSpeed fixes and a cleanup

[Greg Kroah-Hartman]

Some small USB gadget fixes, and one cleanup patch at the end.

The first 4 of these come from the Android kernel tree, where they fix
the gadget drivers to work properly as a SuperSpeed device, odd that no
one else has hit this before.

The last one is a cleanup patch removing the abuse of likely/unlikely
from the f_fs driver.

Changes from v2:
 - added reviewed-by from Peter
 - added additional whitespace to patch 3
 - added 4th patch
 - added this cover letter

Greg Kroah-Hartman (1):
  USB: gadget: f_fs: remove likely/unlikely

Will McVicker (2):
  USB: gadget: f_rndis: fix bitrate for SuperSpeed and above
  USB: gadget: f_midi: setup SuperSpeed Plus descriptors

taehyun.cho (2):
  USB: gadget: f_acm: add support for SuperSpeed Plus
  USB: gadget: f_fs: add SuperSpeed Plus support

 drivers/usb/gadget/function/f_acm.c   |   2 +-
 drivers/usb/gadget/function/f_fs.c    | 182 +++++++++++++-------------
 drivers/usb/gadget/function/f_midi.c  |   6 +
 drivers/usb/gadget/function/f_rndis.c |   4 +-
 4 files changed, 103 insertions(+), 91 deletions(-)

-- 
2.29.2

[PATCH v2 1/5] USB: gadget: f_rndis: fix bitrate for SuperSpeed and above

[Greg Kroah-Hartman]

From: Will McVicker <willmcvicker@google.com>

Align the SuperSpeed Plus bitrate for f_rndis to match f_ncm's ncm_bitrate
defined by commit 1650113888fe ("usb: gadget: f_ncm: add SuperSpeed descriptors
for CDC NCM").

Cc: Felipe Balbi <balbi@kernel.org>
Cc: EJ Hsu <ejh@nvidia.com>
Cc: Peter Chen <peter.chen@nxp.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Will McVicker <willmcvicker@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/gadget/function/f_rndis.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
index 9534c8ab62a8..0739b05a0ef7 100644
--- a/drivers/usb/gadget/function/f_rndis.c
+++ b/drivers/usb/gadget/function/f_rndis.c
@@ -87,8 +87,10 @@ static inline struct f_rndis *func_to_rndis(struct usb_function *f)
 /* peak (theoretical) bulk transfer rate in bits-per-second */
 static unsigned int bitrate(struct usb_gadget *g)
 {
+	if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
+		return 4250000000U;
 	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
-		return 13 * 1024 * 8 * 1000 * 8;
+		return 3750000000U;
 	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
 		return 13 * 512 * 8 * 1000 * 8;
 	else
-- 
2.29.2

Re: [PATCH v2 1/5] USB: gadget: f_rndis: fix bitrate for SuperSpeed and above

[Peter Chen]

On 20-11-27 15:05:55, Greg Kroah-Hartman wrote:
> From: Will McVicker <willmcvicker@google.com>
> 
> Align the SuperSpeed Plus bitrate for f_rndis to match f_ncm's ncm_bitrate
> defined by commit 1650113888fe ("usb: gadget: f_ncm: add SuperSpeed descriptors
> for CDC NCM").
> 
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: EJ Hsu <ejh@nvidia.com>
> Cc: Peter Chen <peter.chen@nxp.com>
> Cc: stable <stable@vger.kernel.org>
> Signed-off-by: Will McVicker <willmcvicker@google.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/usb/gadget/function/f_rndis.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
> index 9534c8ab62a8..0739b05a0ef7 100644
> --- a/drivers/usb/gadget/function/f_rndis.c
> +++ b/drivers/usb/gadget/function/f_rndis.c
> @@ -87,8 +87,10 @@ static inline struct f_rndis *func_to_rndis(struct usb_function *f)
>  /* peak (theoretical) bulk transfer rate in bits-per-second */
>  static unsigned int bitrate(struct usb_gadget *g)
>  {
> +	if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
> +		return 4250000000U;

Is tested value or spec defined value?

>  	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
> -		return 13 * 1024 * 8 * 1000 * 8;
> +		return 3750000000U;

13 * 1024 * 8 * 1000 * 8 = 851,968,000, how 3750000000U is calculated?

>  	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
>  		return 13 * 512 * 8 * 1000 * 8;
>  	else
> -- 
> 2.29.2
> 

-- 

Thanks,
Peter Chen

Re: [PATCH v2 1/5] USB: gadget: f_rndis: fix bitrate for SuperSpeed and above

[William Mcvicker]

On Mon, Nov 30, 2020 at 06:24:40AM +0000, Peter Chen wrote:
> On 20-11-27 15:05:55, Greg Kroah-Hartman wrote:
> > From: Will McVicker <willmcvicker@google.com>
> > 
> > Align the SuperSpeed Plus bitrate for f_rndis to match f_ncm's ncm_bitrate
> > defined by commit 1650113888fe ("usb: gadget: f_ncm: add SuperSpeed descriptors
> > for CDC NCM").
> > 
> > Cc: Felipe Balbi <balbi@kernel.org>
> > Cc: EJ Hsu <ejh@nvidia.com>
> > Cc: Peter Chen <peter.chen@nxp.com>
> > Cc: stable <stable@vger.kernel.org>
> > Signed-off-by: Will McVicker <willmcvicker@google.com>
> > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > ---
> >  drivers/usb/gadget/function/f_rndis.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
> > index 9534c8ab62a8..0739b05a0ef7 100644
> > --- a/drivers/usb/gadget/function/f_rndis.c
> > +++ b/drivers/usb/gadget/function/f_rndis.c
> > @@ -87,8 +87,10 @@ static inline struct f_rndis *func_to_rndis(struct usb_function *f)
> >  /* peak (theoretical) bulk transfer rate in bits-per-second */
> >  static unsigned int bitrate(struct usb_gadget *g)
> >  {
> > +	if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
> > +		return 4250000000U;
> 
> Is tested value or spec defined value?
> 
> >  	if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
> > -		return 13 * 1024 * 8 * 1000 * 8;
> > +		return 3750000000U;
> 
> 13 * 1024 * 8 * 1000 * 8 = 851,968,000, how 3750000000U is calculated?
> 
> >  	else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
> >  		return 13 * 512 * 8 * 1000 * 8;
> >  	else
> > -- 
> > 2.29.2
> > 
> 
> -- 
> 
> Thanks,
> Peter Chen

Hi Peter,

Thanks for the reviews! Regarding the updated transfer rates, please refer to
the f_ncm commit email thread by Lorenzo that explains the reasoning behind
these speeds:

https://patchwork.kernel.org/project/linux-usb/patch/20200818165848.4117493-1-lorenzo@google.com/

Thanks,
Will

Re: [PATCH v2 1/5] USB: gadget: f_rndis: fix bitrate for SuperSpeed and above

[Peter Chen]

>
> From: Will McVicker <willmcvicker@google.com>
>

Reviewed-by: Peter Chen <peter.chen@nxp.com>

Peter
> Align the SuperSpeed Plus bitrate for f_rndis to match f_ncm's ncm_bitrate
> defined by commit 1650113888fe ("usb: gadget: f_ncm: add SuperSpeed descriptors
> for CDC NCM").
>
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: EJ Hsu <ejh@nvidia.com>
> Cc: Peter Chen <peter.chen@nxp.com>
> Cc: stable <stable@vger.kernel.org>
> Signed-off-by: Will McVicker <willmcvicker@google.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/usb/gadget/function/f_rndis.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/usb/gadget/function/f_rndis.c b/drivers/usb/gadget/function/f_rndis.c
> index 9534c8ab62a8..0739b05a0ef7 100644
> --- a/drivers/usb/gadget/function/f_rndis.c
> +++ b/drivers/usb/gadget/function/f_rndis.c
> @@ -87,8 +87,10 @@ static inline struct f_rndis *func_to_rndis(struct usb_function *f)
>  /* peak (theoretical) bulk transfer rate in bits-per-second */
>  static unsigned int bitrate(struct usb_gadget *g)
>  {
> +       if (gadget_is_superspeed(g) && g->speed >= USB_SPEED_SUPER_PLUS)
> +               return 4250000000U;
>         if (gadget_is_superspeed(g) && g->speed == USB_SPEED_SUPER)
> -               return 13 * 1024 * 8 * 1000 * 8;
> +               return 3750000000U;
>         else if (gadget_is_dualspeed(g) && g->speed == USB_SPEED_HIGH)
>                 return 13 * 512 * 8 * 1000 * 8;
>         else
> --
> 2.29.2
>

[PATCH v2 2/5] USB: gadget: f_acm: add support for SuperSpeed Plus

[Greg Kroah-Hartman]

From: "taehyun.cho" <taehyun.cho@samsung.com>

Setup the SuperSpeed Plus descriptors for f_acm.  This allows the gadget
to work properly without crashing at SuperSpeed rates.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: taehyun.cho <taehyun.cho@samsung.com>
Signed-off-by: Will McVicker <willmcvicker@google.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/gadget/function/f_acm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/f_acm.c b/drivers/usb/gadget/function/f_acm.c
index 46647bfac2ef..349945e064bb 100644
--- a/drivers/usb/gadget/function/f_acm.c
+++ b/drivers/usb/gadget/function/f_acm.c
@@ -686,7 +686,7 @@ acm_bind(struct usb_configuration *c, struct usb_function *f)
 	acm_ss_out_desc.bEndpointAddress = acm_fs_out_desc.bEndpointAddress;
 
 	status = usb_assign_descriptors(f, acm_fs_function, acm_hs_function,
-			acm_ss_function, NULL);
+			acm_ss_function, acm_ss_function);
 	if (status)
 		goto fail;
 
-- 
2.29.2

[PATCH v2 3/5] USB: gadget: f_midi: setup SuperSpeed Plus descriptors

[Greg Kroah-Hartman]

From: Will McVicker <willmcvicker@google.com>

Needed for SuperSpeed Plus support for f_midi.  This allows the
gadget to work properly without crashing at SuperSpeed rates.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Will McVicker <willmcvicker@google.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/gadget/function/f_midi.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/usb/gadget/function/f_midi.c b/drivers/usb/gadget/function/f_midi.c
index 85cb15734aa8..974a2d931c3b 100644
--- a/drivers/usb/gadget/function/f_midi.c
+++ b/drivers/usb/gadget/function/f_midi.c
@@ -1048,6 +1048,12 @@ static int f_midi_bind(struct usb_configuration *c, struct usb_function *f)
 		f->ss_descriptors = usb_copy_descriptors(midi_function);
 		if (!f->ss_descriptors)
 			goto fail_f_midi;
+
+		if (gadget_is_superspeed_plus(c->cdev->gadget)) {
+			f->ssp_descriptors = usb_copy_descriptors(midi_function);
+			if (!f->ssp_descriptors)
+				goto fail_f_midi;
+		}
 	}
 
 	kfree(midi_function);
-- 
2.29.2

[PATCH v2 4/5] USB: gadget: f_fs: add SuperSpeed Plus support

[Greg Kroah-Hartman]

From: "taehyun.cho" <taehyun.cho@samsung.com>

Setup the descriptors for SuperSpeed Plus for f_fs. This allows the
gadget to work properly without crashing at SuperSpeed rates.

Cc: Felipe Balbi <balbi@kernel.org>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: taehyun.cho <taehyun.cho@samsung.com>
Signed-off-by: Will McVicker <willmcvicker@google.com>
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/gadget/function/f_fs.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index 046f770a76da..a34a7c96a1ab 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -1327,6 +1327,7 @@ static long ffs_epfile_ioctl(struct file *file, unsigned code,
 		struct usb_endpoint_descriptor *desc;
 
 		switch (epfile->ffs->gadget->speed) {
+		case USB_SPEED_SUPER_PLUS:
 		case USB_SPEED_SUPER:
 			desc_idx = 2;
 			break;
@@ -3222,6 +3223,10 @@ static int _ffs_func_bind(struct usb_configuration *c,
 	func->function.os_desc_n =
 		c->cdev->use_os_string ? ffs->interfaces_count : 0;
 
+	if (likely(super)) {
+		func->function.ssp_descriptors =
+			usb_copy_descriptors(func->function.ss_descriptors);
+	}
 	/* And we're done */
 	ffs_event_add(ffs, FUNCTIONFS_BIND);
 	return 0;
-- 
2.29.2

Re: [PATCH v2 4/5] USB: gadget: f_fs: add SuperSpeed Plus support

[Jack Pham]

On Fri, Nov 27, 2020 at 03:05:58PM +0100, Greg Kroah-Hartman wrote:
> From: "taehyun.cho" <taehyun.cho@samsung.com>
> 
> Setup the descriptors for SuperSpeed Plus for f_fs. This allows the
> gadget to work properly without crashing at SuperSpeed rates.
> 
> Cc: Felipe Balbi <balbi@kernel.org>
> Cc: stable <stable@vger.kernel.org>
> Signed-off-by: taehyun.cho <taehyun.cho@samsung.com>
> Signed-off-by: Will McVicker <willmcvicker@google.com>
> Reviewed-by: Peter Chen <peter.chen@nxp.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> ---
>  drivers/usb/gadget/function/f_fs.c | 5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index 046f770a76da..a34a7c96a1ab 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -1327,6 +1327,7 @@ static long ffs_epfile_ioctl(struct file *file, unsigned code,
>  		struct usb_endpoint_descriptor *desc;
>  
>  		switch (epfile->ffs->gadget->speed) {
> +		case USB_SPEED_SUPER_PLUS:
>  		case USB_SPEED_SUPER:
>  			desc_idx = 2;
>  			break;
> @@ -3222,6 +3223,10 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  	func->function.os_desc_n =
>  		c->cdev->use_os_string ? ffs->interfaces_count : 0;
>  
> +	if (likely(super)) {
> +		func->function.ssp_descriptors =
> +			usb_copy_descriptors(func->function.ss_descriptors);
> +	}
>  	/* And we're done */
>  	ffs_event_add(ffs, FUNCTIONFS_BIND);
>  	return 0;
> -- 

Hi Greg,

FWIW I had sent a very similar patch[1] a while back (twice in fact)
but got no response about it. Looks like Taehyun's patch already went
through Google for this, I assume it must be working on their Android
kernels so I've no problem with you or Felipe taking this instead.

Only one difference with my patch though is mine additionally clears the
func->function.ssp_descriptors member to NULL upon ffs_func_unbind() as
otherwise it could lead to a dangling reference in case the function is
re-bound and userspace does not issue SS descriptors the next time.
Realistically I don't think that's possible, except maybe when fuzzing?

[1] https://patchwork.kernel.org/project/linux-usb/patch/20201027230731.9073-1-jackp@codeaurora.org/

Jack
-- 
The Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

Re: [PATCH v2 4/5] USB: gadget: f_fs: add SuperSpeed Plus support

[Greg Kroah-Hartman]

On Tue, Dec 01, 2020 at 02:32:18AM +0000, Peter Chen wrote:
> On 20-11-30 01:13:00, Jack Pham wrote:
> > On Fri, Nov 27, 2020 at 03:05:58PM +0100, Greg Kroah-Hartman wrote:
> > > From: "taehyun.cho" <taehyun.cho@samsung.com>
> > > 
> > > Setup the descriptors for SuperSpeed Plus for f_fs. This allows the
> > > gadget to work properly without crashing at SuperSpeed rates.
> > > 
> > > Cc: Felipe Balbi <balbi@kernel.org>
> > > Cc: stable <stable@vger.kernel.org>
> > > Signed-off-by: taehyun.cho <taehyun.cho@samsung.com>
> > > Signed-off-by: Will McVicker <willmcvicker@google.com>
> > > Reviewed-by: Peter Chen <peter.chen@nxp.com>
> > > Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > > ---
> > >  drivers/usb/gadget/function/f_fs.c | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > > 
> > > diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> > > index 046f770a76da..a34a7c96a1ab 100644
> > > --- a/drivers/usb/gadget/function/f_fs.c
> > > +++ b/drivers/usb/gadget/function/f_fs.c
> > > @@ -1327,6 +1327,7 @@ static long ffs_epfile_ioctl(struct file *file, unsigned code,
> > >  		struct usb_endpoint_descriptor *desc;
> > >  
> > >  		switch (epfile->ffs->gadget->speed) {
> > > +		case USB_SPEED_SUPER_PLUS:
> > >  		case USB_SPEED_SUPER:
> > >  			desc_idx = 2;
> > >  			break;
> > > @@ -3222,6 +3223,10 @@ static int _ffs_func_bind(struct usb_configuration *c,
> > >  	func->function.os_desc_n =
> > >  		c->cdev->use_os_string ? ffs->interfaces_count : 0;
> > >  
> > > +	if (likely(super)) {
> > > +		func->function.ssp_descriptors =
> > > +			usb_copy_descriptors(func->function.ss_descriptors);
> > > +	}
> > >  	/* And we're done */
> > >  	ffs_event_add(ffs, FUNCTIONFS_BIND);
> > >  	return 0;
> > > -- 
> > 
> > Hi Greg,
> > 
> > FWIW I had sent a very similar patch[1] a while back (twice in fact)
> > but got no response about it. Looks like Taehyun's patch already went
> > through Google for this, I assume it must be working on their Android
> > kernels so I've no problem with you or Felipe taking this instead.
> > 
> > Only one difference with my patch though is mine additionally clears the
> > func->function.ssp_descriptors member to NULL upon ffs_func_unbind() as
> > otherwise it could lead to a dangling reference in case the function is
> > re-bound and userspace does not issue SS descriptors the next time.
> > Realistically I don't think that's possible, except maybe when fuzzing?
> > 
> 
> Yours is better, since there is no judgement for
> func->function.ssp_descriptors at __ffs_func_bind_do_descs, without
> clearing its value can't cause problem.

Ok, I've taken the older patch instead, thanks!

greg k-h

[PATCH v2 5/5] USB: gadget: f_fs: remove likely/unlikely

[Greg Kroah-Hartman]

They are used way too often in this file, in some ways that are actually
wrong.  Almost all of these are already known by the compiler and CPU so
just remove them all as none of these should be on any "hot paths" where
it actually matters.

Cc: Felipe Balbi <balbi@kernel.org>
Reported-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 drivers/usb/gadget/function/f_fs.c | 179 ++++++++++++++---------------
 1 file changed, 89 insertions(+), 90 deletions(-)

diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
index a34a7c96a1ab..9047b20b6715 100644
--- a/drivers/usb/gadget/function/f_fs.c
+++ b/drivers/usb/gadget/function/f_fs.c
@@ -296,11 +296,11 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
 	reinit_completion(&ffs->ep0req_completion);
 
 	ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
-	if (unlikely(ret < 0))
+	if (ret < 0)
 		return ret;
 
 	ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
-	if (unlikely(ret)) {
+	if (ret) {
 		usb_ep_dequeue(ffs->gadget->ep0, req);
 		return -EINTR;
 	}
@@ -337,7 +337,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 
 	/* Acquire mutex */
 	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
-	if (unlikely(ret < 0))
+	if (ret < 0)
 		return ret;
 
 	/* Check state */
@@ -345,7 +345,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 	case FFS_READ_DESCRIPTORS:
 	case FFS_READ_STRINGS:
 		/* Copy data */
-		if (unlikely(len < 16)) {
+		if (len < 16) {
 			ret = -EINVAL;
 			break;
 		}
@@ -360,7 +360,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 		if (ffs->state == FFS_READ_DESCRIPTORS) {
 			pr_info("read descriptors\n");
 			ret = __ffs_data_got_descs(ffs, data, len);
-			if (unlikely(ret < 0))
+			if (ret < 0)
 				break;
 
 			ffs->state = FFS_READ_STRINGS;
@@ -368,11 +368,11 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 		} else {
 			pr_info("read strings\n");
 			ret = __ffs_data_got_strings(ffs, data, len);
-			if (unlikely(ret < 0))
+			if (ret < 0)
 				break;
 
 			ret = ffs_epfiles_create(ffs);
-			if (unlikely(ret)) {
+			if (ret) {
 				ffs->state = FFS_CLOSING;
 				break;
 			}
@@ -381,7 +381,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
 			mutex_unlock(&ffs->mutex);
 
 			ret = ffs_ready(ffs);
-			if (unlikely(ret < 0)) {
+			if (ret < 0) {
 				ffs->state = FFS_CLOSING;
 				return ret;
 			}
@@ -495,7 +495,7 @@ static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
 	spin_unlock_irq(&ffs->ev.waitq.lock);
 	mutex_unlock(&ffs->mutex);
 
-	return unlikely(copy_to_user(buf, events, size)) ? -EFAULT : size;
+	return copy_to_user(buf, events, size) ? -EFAULT : size;
 }
 
 static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
@@ -514,7 +514,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
 
 	/* Acquire mutex */
 	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
-	if (unlikely(ret < 0))
+	if (ret < 0)
 		return ret;
 
 	/* Check state */
@@ -536,7 +536,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
 
 	case FFS_NO_SETUP:
 		n = len / sizeof(struct usb_functionfs_event);
-		if (unlikely(!n)) {
+		if (!n) {
 			ret = -EINVAL;
 			break;
 		}
@@ -567,9 +567,9 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
 
 		spin_unlock_irq(&ffs->ev.waitq.lock);
 
-		if (likely(len)) {
+		if (len) {
 			data = kmalloc(len, GFP_KERNEL);
-			if (unlikely(!data)) {
+			if (!data) {
 				ret = -ENOMEM;
 				goto done_mutex;
 			}
@@ -586,7 +586,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
 
 		/* unlocks spinlock */
 		ret = __ffs_ep0_queue_wait(ffs, data, len);
-		if (likely(ret > 0) && unlikely(copy_to_user(buf, data, len)))
+		if ((ret > 0) && (copy_to_user(buf, data, len)))
 			ret = -EFAULT;
 		goto done_mutex;
 
@@ -608,7 +608,7 @@ static int ffs_ep0_open(struct inode *inode, struct file *file)
 
 	ENTER();
 
-	if (unlikely(ffs->state == FFS_CLOSING))
+	if (ffs->state == FFS_CLOSING)
 		return -EBUSY;
 
 	file->private_data = ffs;
@@ -657,7 +657,7 @@ static __poll_t ffs_ep0_poll(struct file *file, poll_table *wait)
 	poll_wait(file, &ffs->ev.waitq, wait);
 
 	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
-	if (unlikely(ret < 0))
+	if (ret < 0)
 		return mask;
 
 	switch (ffs->state) {
@@ -706,7 +706,7 @@ static const struct file_operations ffs_ep0_operations = {
 static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
 {
 	ENTER();
-	if (likely(req->context)) {
+	if (req->context) {
 		struct ffs_ep *ep = _ep->driver_data;
 		ep->status = req->status ? req->status : req->actual;
 		complete(req->context);
@@ -716,10 +716,10 @@ static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
 static ssize_t ffs_copy_to_iter(void *data, int data_len, struct iov_iter *iter)
 {
 	ssize_t ret = copy_to_iter(data, data_len, iter);
-	if (likely(ret == data_len))
+	if (ret == data_len)
 		return ret;
 
-	if (unlikely(iov_iter_count(iter)))
+	if (iov_iter_count(iter))
 		return -EFAULT;
 
 	/*
@@ -885,7 +885,7 @@ static ssize_t __ffs_epfile_read_buffered(struct ffs_epfile *epfile,
 		return ret;
 	}
 
-	if (unlikely(iov_iter_count(iter))) {
+	if (iov_iter_count(iter)) {
 		ret = -EFAULT;
 	} else {
 		buf->length -= ret;
@@ -906,10 +906,10 @@ static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
 	struct ffs_buffer *buf;
 
 	ssize_t ret = copy_to_iter(data, data_len, iter);
-	if (likely(data_len == ret))
+	if (data_len == ret)
 		return ret;
 
-	if (unlikely(iov_iter_count(iter)))
+	if (iov_iter_count(iter))
 		return -EFAULT;
 
 	/* See ffs_copy_to_iter for more context. */
@@ -930,7 +930,7 @@ static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
 	 * in struct ffs_epfile for full read_buffer pointer synchronisation
 	 * story.
 	 */
-	if (unlikely(cmpxchg(&epfile->read_buffer, NULL, buf)))
+	if (cmpxchg(&epfile->read_buffer, NULL, buf))
 		kfree(buf);
 
 	return ret;
@@ -968,7 +968,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 
 	/* We will be using request and read_buffer */
 	ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
-	if (unlikely(ret))
+	if (ret)
 		goto error;
 
 	/* Allocate & copy */
@@ -1013,7 +1013,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		spin_unlock_irq(&epfile->ffs->eps_lock);
 
 		data = ffs_alloc_buffer(io_data, data_len);
-		if (unlikely(!data)) {
+		if (!data) {
 			ret = -ENOMEM;
 			goto error_mutex;
 		}
@@ -1033,7 +1033,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		ret = usb_ep_set_halt(ep->ep);
 		if (!ret)
 			ret = -EBADMSG;
-	} else if (unlikely(data_len == -EINVAL)) {
+	} else if (data_len == -EINVAL) {
 		/*
 		 * Sanity Check: even though data_len can't be used
 		 * uninitialized at the time I write this comment, some
@@ -1068,12 +1068,12 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		req->complete = ffs_epfile_io_complete;
 
 		ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
-		if (unlikely(ret < 0))
+		if (ret < 0)
 			goto error_lock;
 
 		spin_unlock_irq(&epfile->ffs->eps_lock);
 
-		if (unlikely(wait_for_completion_interruptible(&done))) {
+		if (wait_for_completion_interruptible(&done)) {
 			/*
 			 * To avoid race condition with ffs_epfile_io_complete,
 			 * dequeue the request first then check
@@ -1115,7 +1115,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
 		req->complete = ffs_epfile_async_io_complete;
 
 		ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
-		if (unlikely(ret)) {
+		if (ret) {
 			io_data->req = NULL;
 			usb_ep_free_request(ep->ep, req);
 			goto error_lock;
@@ -1166,7 +1166,7 @@ static int ffs_aio_cancel(struct kiocb *kiocb)
 
 	spin_lock_irqsave(&epfile->ffs->eps_lock, flags);
 
-	if (likely(io_data && io_data->ep && io_data->req))
+	if (io_data && io_data->ep && io_data->req)
 		value = usb_ep_dequeue(io_data->ep, io_data->req);
 	else
 		value = -EINVAL;
@@ -1185,7 +1185,7 @@ static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
 
 	if (!is_sync_kiocb(kiocb)) {
 		p = kzalloc(sizeof(io_data), GFP_KERNEL);
-		if (unlikely(!p))
+		if (!p)
 			return -ENOMEM;
 		p->aio = true;
 	} else {
@@ -1222,7 +1222,7 @@ static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
 
 	if (!is_sync_kiocb(kiocb)) {
 		p = kzalloc(sizeof(io_data), GFP_KERNEL);
-		if (unlikely(!p))
+		if (!p)
 			return -ENOMEM;
 		p->aio = true;
 	} else {
@@ -1384,7 +1384,7 @@ ffs_sb_make_inode(struct super_block *sb, void *data,
 
 	inode = new_inode(sb);
 
-	if (likely(inode)) {
+	if (inode) {
 		struct timespec64 ts = current_time(inode);
 
 		inode->i_ino	 = get_next_ino();
@@ -1416,11 +1416,11 @@ static struct dentry *ffs_sb_create_file(struct super_block *sb,
 	ENTER();
 
 	dentry = d_alloc_name(sb->s_root, name);
-	if (unlikely(!dentry))
+	if (!dentry)
 		return NULL;
 
 	inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
-	if (unlikely(!inode)) {
+	if (!inode) {
 		dput(dentry);
 		return NULL;
 	}
@@ -1467,12 +1467,11 @@ static int ffs_sb_fill(struct super_block *sb, struct fs_context *fc)
 				  &simple_dir_inode_operations,
 				  &data->perms);
 	sb->s_root = d_make_root(inode);
-	if (unlikely(!sb->s_root))
+	if (!sb->s_root)
 		return -ENOMEM;
 
 	/* EP0 file */
-	if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
-					 &ffs_ep0_operations)))
+	if (!ffs_sb_create_file(sb, "ep0", ffs, &ffs_ep0_operations))
 		return -ENOMEM;
 
 	return 0;
@@ -1560,13 +1559,13 @@ static int ffs_fs_get_tree(struct fs_context *fc)
 		return invalf(fc, "No source specified");
 
 	ffs = ffs_data_new(fc->source);
-	if (unlikely(!ffs))
+	if (!ffs)
 		return -ENOMEM;
 	ffs->file_perms = ctx->perms;
 	ffs->no_disconnect = ctx->no_disconnect;
 
 	ffs->dev_name = kstrdup(fc->source, GFP_KERNEL);
-	if (unlikely(!ffs->dev_name)) {
+	if (!ffs->dev_name) {
 		ffs_data_put(ffs);
 		return -ENOMEM;
 	}
@@ -1652,7 +1651,7 @@ static int functionfs_init(void)
 	ENTER();
 
 	ret = register_filesystem(&ffs_fs_type);
-	if (likely(!ret))
+	if (!ret)
 		pr_info("file system registered\n");
 	else
 		pr_err("failed registering file system (%d)\n", ret);
@@ -1697,7 +1696,7 @@ static void ffs_data_put(struct ffs_data *ffs)
 {
 	ENTER();
 
-	if (unlikely(refcount_dec_and_test(&ffs->ref))) {
+	if (refcount_dec_and_test(&ffs->ref)) {
 		pr_info("%s(): freeing\n", __func__);
 		ffs_data_clear(ffs);
 		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
@@ -1739,7 +1738,7 @@ static void ffs_data_closed(struct ffs_data *ffs)
 static struct ffs_data *ffs_data_new(const char *dev_name)
 {
 	struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
-	if (unlikely(!ffs))
+	if (!ffs)
 		return NULL;
 
 	ENTER();
@@ -1829,11 +1828,11 @@ static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
 		return -EBADFD;
 
 	first_id = usb_string_ids_n(cdev, ffs->strings_count);
-	if (unlikely(first_id < 0))
+	if (first_id < 0)
 		return first_id;
 
 	ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
-	if (unlikely(!ffs->ep0req))
+	if (!ffs->ep0req)
 		return -ENOMEM;
 	ffs->ep0req->complete = ffs_ep0_complete;
 	ffs->ep0req->context = ffs;
@@ -1889,7 +1888,7 @@ static int ffs_epfiles_create(struct ffs_data *ffs)
 		epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
 						 epfile,
 						 &ffs_epfile_operations);
-		if (unlikely(!epfile->dentry)) {
+		if (!epfile->dentry) {
 			ffs_epfiles_destroy(epfiles, i - 1);
 			return -ENOMEM;
 		}
@@ -1927,7 +1926,7 @@ static void ffs_func_eps_disable(struct ffs_function *func)
 	spin_lock_irqsave(&func->ffs->eps_lock, flags);
 	while (count--) {
 		/* pending requests get nuked */
-		if (likely(ep->ep))
+		if (ep->ep)
 			usb_ep_disable(ep->ep);
 		++ep;
 
@@ -1961,7 +1960,7 @@ static int ffs_func_eps_enable(struct ffs_function *func)
 		}
 
 		ret = usb_ep_enable(ep->ep);
-		if (likely(!ret)) {
+		if (!ret) {
 			epfile->ep = ep;
 			epfile->in = usb_endpoint_dir_in(ep->ep->desc);
 			epfile->isoc = usb_endpoint_xfer_isoc(ep->ep->desc);
@@ -2034,12 +2033,12 @@ static int __must_check ffs_do_single_desc(char *data, unsigned len,
 #define __entity_check_ENDPOINT(val)   ((val) & USB_ENDPOINT_NUMBER_MASK)
 #define __entity(type, val) do {					\
 		pr_vdebug("entity " #type "(%02x)\n", (val));		\
-		if (unlikely(!__entity_check_ ##type(val))) {		\
+		if (!__entity_check_ ##type(val)) {			\
 			pr_vdebug("invalid entity's value\n");		\
 			return -EINVAL;					\
 		}							\
 		ret = entity(FFS_ ##type, &val, _ds, priv);		\
-		if (unlikely(ret < 0)) {				\
+		if (ret < 0) {						\
 			pr_debug("entity " #type "(%02x); ret = %d\n",	\
 				 (val), ret);				\
 			return ret;					\
@@ -2164,7 +2163,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
 
 		/* Record "descriptor" entity */
 		ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
-		if (unlikely(ret < 0)) {
+		if (ret < 0) {
 			pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
 				 num, ret);
 			return ret;
@@ -2175,7 +2174,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
 
 		ret = ffs_do_single_desc(data, len, entity, priv,
 			&current_class);
-		if (unlikely(ret < 0)) {
+		if (ret < 0) {
 			pr_debug("%s returns %d\n", __func__, ret);
 			return ret;
 		}
@@ -2281,7 +2280,7 @@ static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
 	/* loop over all ext compat/ext prop descriptors */
 	while (feature_count--) {
 		ret = entity(type, h, data, len, priv);
-		if (unlikely(ret < 0)) {
+		if (ret < 0) {
 			pr_debug("bad OS descriptor, type: %d\n", type);
 			return ret;
 		}
@@ -2321,7 +2320,7 @@ static int __must_check ffs_do_os_descs(unsigned count,
 			return -EINVAL;
 
 		ret = __ffs_do_os_desc_header(&type, desc);
-		if (unlikely(ret < 0)) {
+		if (ret < 0) {
 			pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
 				 num, ret);
 			return ret;
@@ -2342,7 +2341,7 @@ static int __must_check ffs_do_os_descs(unsigned count,
 		 */
 		ret = ffs_do_single_os_desc(data, len, type,
 					    feature_count, entity, priv, desc);
-		if (unlikely(ret < 0)) {
+		if (ret < 0) {
 			pr_debug("%s returns %d\n", __func__, ret);
 			return ret;
 		}
@@ -2574,20 +2573,20 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 
 	ENTER();
 
-	if (unlikely(len < 16 ||
-		     get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
-		     get_unaligned_le32(data + 4) != len))
+	if (len < 16 ||
+	    get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
+	    get_unaligned_le32(data + 4) != len)
 		goto error;
 	str_count  = get_unaligned_le32(data + 8);
 	lang_count = get_unaligned_le32(data + 12);
 
 	/* if one is zero the other must be zero */
-	if (unlikely(!str_count != !lang_count))
+	if (!str_count != !lang_count)
 		goto error;
 
 	/* Do we have at least as many strings as descriptors need? */
 	needed_count = ffs->strings_count;
-	if (unlikely(str_count < needed_count))
+	if (str_count < needed_count)
 		goto error;
 
 	/*
@@ -2611,7 +2610,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 
 		char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
 
-		if (unlikely(!vlabuf)) {
+		if (!vlabuf) {
 			kfree(_data);
 			return -ENOMEM;
 		}
@@ -2638,7 +2637,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 	do { /* lang_count > 0 so we can use do-while */
 		unsigned needed = needed_count;
 
-		if (unlikely(len < 3))
+		if (len < 3)
 			goto error_free;
 		t->language = get_unaligned_le16(data);
 		t->strings  = s;
@@ -2651,7 +2650,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 		do { /* str_count > 0 so we can use do-while */
 			size_t length = strnlen(data, len);
 
-			if (unlikely(length == len))
+			if (length == len)
 				goto error_free;
 
 			/*
@@ -2659,7 +2658,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 			 * if that's the case we simply ignore the
 			 * rest
 			 */
-			if (likely(needed)) {
+			if (needed) {
 				/*
 				 * s->id will be set while adding
 				 * function to configuration so for
@@ -2681,7 +2680,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
 	} while (--lang_count);
 
 	/* Some garbage left? */
-	if (unlikely(len))
+	if (len)
 		goto error_free;
 
 	/* Done! */
@@ -2828,7 +2827,7 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
 
 	ffs_ep = func->eps + idx;
 
-	if (unlikely(ffs_ep->descs[ep_desc_id])) {
+	if (ffs_ep->descs[ep_desc_id]) {
 		pr_err("two %sspeed descriptors for EP %d\n",
 			  speed_names[ep_desc_id],
 			  ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
@@ -2859,12 +2858,12 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
 		wMaxPacketSize = ds->wMaxPacketSize;
 		pr_vdebug("autoconfig\n");
 		ep = usb_ep_autoconfig(func->gadget, ds);
-		if (unlikely(!ep))
+		if (!ep)
 			return -ENOTSUPP;
 		ep->driver_data = func->eps + idx;
 
 		req = usb_ep_alloc_request(ep, GFP_KERNEL);
-		if (unlikely(!req))
+		if (!req)
 			return -ENOMEM;
 
 		ffs_ep->ep  = ep;
@@ -2906,7 +2905,7 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
 		idx = *valuep;
 		if (func->interfaces_nums[idx] < 0) {
 			int id = usb_interface_id(func->conf, &func->function);
-			if (unlikely(id < 0))
+			if (id < 0)
 				return id;
 			func->interfaces_nums[idx] = id;
 		}
@@ -2927,7 +2926,7 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
 			return 0;
 
 		idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
-		if (unlikely(!func->eps[idx].ep))
+		if (!func->eps[idx].ep)
 			return -EINVAL;
 
 		{
@@ -3110,12 +3109,12 @@ static int _ffs_func_bind(struct usb_configuration *c,
 	ENTER();
 
 	/* Has descriptors only for speeds gadget does not support */
-	if (unlikely(!(full | high | super)))
+	if (!(full | high | super))
 		return -ENOTSUPP;
 
 	/* Allocate a single chunk, less management later on */
 	vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
-	if (unlikely(!vlabuf))
+	if (!vlabuf)
 		return -ENOMEM;
 
 	ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
@@ -3144,13 +3143,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
 	 * endpoints first, so that later we can rewrite the endpoint
 	 * numbers without worrying that it may be described later on.
 	 */
-	if (likely(full)) {
+	if (full) {
 		func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
 		fs_len = ffs_do_descs(ffs->fs_descs_count,
 				      vla_ptr(vlabuf, d, raw_descs),
 				      d_raw_descs__sz,
 				      __ffs_func_bind_do_descs, func);
-		if (unlikely(fs_len < 0)) {
+		if (fs_len < 0) {
 			ret = fs_len;
 			goto error;
 		}
@@ -3158,13 +3157,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
 		fs_len = 0;
 	}
 
-	if (likely(high)) {
+	if (high) {
 		func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
 		hs_len = ffs_do_descs(ffs->hs_descs_count,
 				      vla_ptr(vlabuf, d, raw_descs) + fs_len,
 				      d_raw_descs__sz - fs_len,
 				      __ffs_func_bind_do_descs, func);
-		if (unlikely(hs_len < 0)) {
+		if (hs_len < 0) {
 			ret = hs_len;
 			goto error;
 		}
@@ -3172,13 +3171,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
 		hs_len = 0;
 	}
 
-	if (likely(super)) {
+	if (super) {
 		func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
 		ss_len = ffs_do_descs(ffs->ss_descs_count,
 				vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
 				d_raw_descs__sz - fs_len - hs_len,
 				__ffs_func_bind_do_descs, func);
-		if (unlikely(ss_len < 0)) {
+		if (ss_len < 0) {
 			ret = ss_len;
 			goto error;
 		}
@@ -3196,7 +3195,7 @@ static int _ffs_func_bind(struct usb_configuration *c,
 			   (super ? ffs->ss_descs_count : 0),
 			   vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
 			   __ffs_func_bind_do_nums, func);
-	if (unlikely(ret < 0))
+	if (ret < 0)
 		goto error;
 
 	func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
@@ -3217,13 +3216,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
 				      d_raw_descs__sz - fs_len - hs_len -
 				      ss_len,
 				      __ffs_func_bind_do_os_desc, func);
-		if (unlikely(ret < 0))
+		if (ret < 0)
 			goto error;
 	}
 	func->function.os_desc_n =
 		c->cdev->use_os_string ? ffs->interfaces_count : 0;
 
-	if (likely(super)) {
+	if (super) {
 		func->function.ssp_descriptors =
 			usb_copy_descriptors(func->function.ss_descriptors);
 	}
@@ -3272,7 +3271,7 @@ static int ffs_func_set_alt(struct usb_function *f,
 
 	if (alt != (unsigned)-1) {
 		intf = ffs_func_revmap_intf(func, interface);
-		if (unlikely(intf < 0))
+		if (intf < 0)
 			return intf;
 	}
 
@@ -3297,7 +3296,7 @@ static int ffs_func_set_alt(struct usb_function *f,
 
 	ffs->func = func;
 	ret = ffs_func_eps_enable(func);
-	if (likely(ret >= 0))
+	if (ret >= 0)
 		ffs_event_add(ffs, FUNCTIONFS_ENABLE);
 	return ret;
 }
@@ -3339,13 +3338,13 @@ static int ffs_func_setup(struct usb_function *f,
 	switch (creq->bRequestType & USB_RECIP_MASK) {
 	case USB_RECIP_INTERFACE:
 		ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
-		if (unlikely(ret < 0))
+		if (ret < 0)
 			return ret;
 		break;
 
 	case USB_RECIP_ENDPOINT:
 		ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
-		if (unlikely(ret < 0))
+		if (ret < 0)
 			return ret;
 		if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
 			ret = func->ffs->eps_addrmap[ret];
@@ -3599,7 +3598,7 @@ static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
 	ENTER();
 
 	func = kzalloc(sizeof(*func), GFP_KERNEL);
-	if (unlikely(!func))
+	if (!func)
 		return ERR_PTR(-ENOMEM);
 
 	func->function.name    = "Function FS Gadget";
@@ -3814,7 +3813,7 @@ static void ffs_closed(struct ffs_data *ffs)
 static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
 {
 	return nonblock
-		? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
+		? mutex_trylock(mutex) ? 0 : -EAGAIN
 		: mutex_lock_interruptible(mutex);
 }
 
@@ -3822,14 +3821,14 @@ static char *ffs_prepare_buffer(const char __user *buf, size_t len)
 {
 	char *data;
 
-	if (unlikely(!len))
+	if (!len)
 		return NULL;
 
 	data = kmalloc(len, GFP_KERNEL);
-	if (unlikely(!data))
+	if (!data)
 		return ERR_PTR(-ENOMEM);
 
-	if (unlikely(copy_from_user(data, buf, len))) {
+	if (copy_from_user(data, buf, len)) {
 		kfree(data);
 		return ERR_PTR(-EFAULT);
 	}
-- 
2.29.2

Re: [PATCH v2 5/5] USB: gadget: f_fs: remove likely/unlikely

[Peter Chen]

On 20-11-27 15:05:59, Greg Kroah-Hartman wrote:
> They are used way too often in this file, in some ways that are actually
> wrong.  Almost all of these are already known by the compiler and CPU so
> just remove them all as none of these should be on any "hot paths" where
> it actually matters.
> 
> Cc: Felipe Balbi <balbi@kernel.org>
> Reported-by: Peter Chen <peter.chen@nxp.com>
> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Reviewed-by: Peter Chen <peter.chen@nxp.com>

> ---
>  drivers/usb/gadget/function/f_fs.c | 179 ++++++++++++++---------------
>  1 file changed, 89 insertions(+), 90 deletions(-)
> 
> diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c
> index a34a7c96a1ab..9047b20b6715 100644
> --- a/drivers/usb/gadget/function/f_fs.c
> +++ b/drivers/usb/gadget/function/f_fs.c
> @@ -296,11 +296,11 @@ static int __ffs_ep0_queue_wait(struct ffs_data *ffs, char *data, size_t len)
>  	reinit_completion(&ffs->ep0req_completion);
>  
>  	ret = usb_ep_queue(ffs->gadget->ep0, req, GFP_ATOMIC);
> -	if (unlikely(ret < 0))
> +	if (ret < 0)
>  		return ret;
>  
>  	ret = wait_for_completion_interruptible(&ffs->ep0req_completion);
> -	if (unlikely(ret)) {
> +	if (ret) {
>  		usb_ep_dequeue(ffs->gadget->ep0, req);
>  		return -EINTR;
>  	}
> @@ -337,7 +337,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
>  
>  	/* Acquire mutex */
>  	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
> -	if (unlikely(ret < 0))
> +	if (ret < 0)
>  		return ret;
>  
>  	/* Check state */
> @@ -345,7 +345,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
>  	case FFS_READ_DESCRIPTORS:
>  	case FFS_READ_STRINGS:
>  		/* Copy data */
> -		if (unlikely(len < 16)) {
> +		if (len < 16) {
>  			ret = -EINVAL;
>  			break;
>  		}
> @@ -360,7 +360,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
>  		if (ffs->state == FFS_READ_DESCRIPTORS) {
>  			pr_info("read descriptors\n");
>  			ret = __ffs_data_got_descs(ffs, data, len);
> -			if (unlikely(ret < 0))
> +			if (ret < 0)
>  				break;
>  
>  			ffs->state = FFS_READ_STRINGS;
> @@ -368,11 +368,11 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
>  		} else {
>  			pr_info("read strings\n");
>  			ret = __ffs_data_got_strings(ffs, data, len);
> -			if (unlikely(ret < 0))
> +			if (ret < 0)
>  				break;
>  
>  			ret = ffs_epfiles_create(ffs);
> -			if (unlikely(ret)) {
> +			if (ret) {
>  				ffs->state = FFS_CLOSING;
>  				break;
>  			}
> @@ -381,7 +381,7 @@ static ssize_t ffs_ep0_write(struct file *file, const char __user *buf,
>  			mutex_unlock(&ffs->mutex);
>  
>  			ret = ffs_ready(ffs);
> -			if (unlikely(ret < 0)) {
> +			if (ret < 0) {
>  				ffs->state = FFS_CLOSING;
>  				return ret;
>  			}
> @@ -495,7 +495,7 @@ static ssize_t __ffs_ep0_read_events(struct ffs_data *ffs, char __user *buf,
>  	spin_unlock_irq(&ffs->ev.waitq.lock);
>  	mutex_unlock(&ffs->mutex);
>  
> -	return unlikely(copy_to_user(buf, events, size)) ? -EFAULT : size;
> +	return copy_to_user(buf, events, size) ? -EFAULT : size;
>  }
>  
>  static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
> @@ -514,7 +514,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
>  
>  	/* Acquire mutex */
>  	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
> -	if (unlikely(ret < 0))
> +	if (ret < 0)
>  		return ret;
>  
>  	/* Check state */
> @@ -536,7 +536,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
>  
>  	case FFS_NO_SETUP:
>  		n = len / sizeof(struct usb_functionfs_event);
> -		if (unlikely(!n)) {
> +		if (!n) {
>  			ret = -EINVAL;
>  			break;
>  		}
> @@ -567,9 +567,9 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
>  
>  		spin_unlock_irq(&ffs->ev.waitq.lock);
>  
> -		if (likely(len)) {
> +		if (len) {
>  			data = kmalloc(len, GFP_KERNEL);
> -			if (unlikely(!data)) {
> +			if (!data) {
>  				ret = -ENOMEM;
>  				goto done_mutex;
>  			}
> @@ -586,7 +586,7 @@ static ssize_t ffs_ep0_read(struct file *file, char __user *buf,
>  
>  		/* unlocks spinlock */
>  		ret = __ffs_ep0_queue_wait(ffs, data, len);
> -		if (likely(ret > 0) && unlikely(copy_to_user(buf, data, len)))
> +		if ((ret > 0) && (copy_to_user(buf, data, len)))
>  			ret = -EFAULT;
>  		goto done_mutex;
>  
> @@ -608,7 +608,7 @@ static int ffs_ep0_open(struct inode *inode, struct file *file)
>  
>  	ENTER();
>  
> -	if (unlikely(ffs->state == FFS_CLOSING))
> +	if (ffs->state == FFS_CLOSING)
>  		return -EBUSY;
>  
>  	file->private_data = ffs;
> @@ -657,7 +657,7 @@ static __poll_t ffs_ep0_poll(struct file *file, poll_table *wait)
>  	poll_wait(file, &ffs->ev.waitq, wait);
>  
>  	ret = ffs_mutex_lock(&ffs->mutex, file->f_flags & O_NONBLOCK);
> -	if (unlikely(ret < 0))
> +	if (ret < 0)
>  		return mask;
>  
>  	switch (ffs->state) {
> @@ -706,7 +706,7 @@ static const struct file_operations ffs_ep0_operations = {
>  static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
>  {
>  	ENTER();
> -	if (likely(req->context)) {
> +	if (req->context) {
>  		struct ffs_ep *ep = _ep->driver_data;
>  		ep->status = req->status ? req->status : req->actual;
>  		complete(req->context);
> @@ -716,10 +716,10 @@ static void ffs_epfile_io_complete(struct usb_ep *_ep, struct usb_request *req)
>  static ssize_t ffs_copy_to_iter(void *data, int data_len, struct iov_iter *iter)
>  {
>  	ssize_t ret = copy_to_iter(data, data_len, iter);
> -	if (likely(ret == data_len))
> +	if (ret == data_len)
>  		return ret;
>  
> -	if (unlikely(iov_iter_count(iter)))
> +	if (iov_iter_count(iter))
>  		return -EFAULT;
>  
>  	/*
> @@ -885,7 +885,7 @@ static ssize_t __ffs_epfile_read_buffered(struct ffs_epfile *epfile,
>  		return ret;
>  	}
>  
> -	if (unlikely(iov_iter_count(iter))) {
> +	if (iov_iter_count(iter)) {
>  		ret = -EFAULT;
>  	} else {
>  		buf->length -= ret;
> @@ -906,10 +906,10 @@ static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
>  	struct ffs_buffer *buf;
>  
>  	ssize_t ret = copy_to_iter(data, data_len, iter);
> -	if (likely(data_len == ret))
> +	if (data_len == ret)
>  		return ret;
>  
> -	if (unlikely(iov_iter_count(iter)))
> +	if (iov_iter_count(iter))
>  		return -EFAULT;
>  
>  	/* See ffs_copy_to_iter for more context. */
> @@ -930,7 +930,7 @@ static ssize_t __ffs_epfile_read_data(struct ffs_epfile *epfile,
>  	 * in struct ffs_epfile for full read_buffer pointer synchronisation
>  	 * story.
>  	 */
> -	if (unlikely(cmpxchg(&epfile->read_buffer, NULL, buf)))
> +	if (cmpxchg(&epfile->read_buffer, NULL, buf))
>  		kfree(buf);
>  
>  	return ret;
> @@ -968,7 +968,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
>  
>  	/* We will be using request and read_buffer */
>  	ret = ffs_mutex_lock(&epfile->mutex, file->f_flags & O_NONBLOCK);
> -	if (unlikely(ret))
> +	if (ret)
>  		goto error;
>  
>  	/* Allocate & copy */
> @@ -1013,7 +1013,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
>  		spin_unlock_irq(&epfile->ffs->eps_lock);
>  
>  		data = ffs_alloc_buffer(io_data, data_len);
> -		if (unlikely(!data)) {
> +		if (!data) {
>  			ret = -ENOMEM;
>  			goto error_mutex;
>  		}
> @@ -1033,7 +1033,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
>  		ret = usb_ep_set_halt(ep->ep);
>  		if (!ret)
>  			ret = -EBADMSG;
> -	} else if (unlikely(data_len == -EINVAL)) {
> +	} else if (data_len == -EINVAL) {
>  		/*
>  		 * Sanity Check: even though data_len can't be used
>  		 * uninitialized at the time I write this comment, some
> @@ -1068,12 +1068,12 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
>  		req->complete = ffs_epfile_io_complete;
>  
>  		ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
> -		if (unlikely(ret < 0))
> +		if (ret < 0)
>  			goto error_lock;
>  
>  		spin_unlock_irq(&epfile->ffs->eps_lock);
>  
> -		if (unlikely(wait_for_completion_interruptible(&done))) {
> +		if (wait_for_completion_interruptible(&done)) {
>  			/*
>  			 * To avoid race condition with ffs_epfile_io_complete,
>  			 * dequeue the request first then check
> @@ -1115,7 +1115,7 @@ static ssize_t ffs_epfile_io(struct file *file, struct ffs_io_data *io_data)
>  		req->complete = ffs_epfile_async_io_complete;
>  
>  		ret = usb_ep_queue(ep->ep, req, GFP_ATOMIC);
> -		if (unlikely(ret)) {
> +		if (ret) {
>  			io_data->req = NULL;
>  			usb_ep_free_request(ep->ep, req);
>  			goto error_lock;
> @@ -1166,7 +1166,7 @@ static int ffs_aio_cancel(struct kiocb *kiocb)
>  
>  	spin_lock_irqsave(&epfile->ffs->eps_lock, flags);
>  
> -	if (likely(io_data && io_data->ep && io_data->req))
> +	if (io_data && io_data->ep && io_data->req)
>  		value = usb_ep_dequeue(io_data->ep, io_data->req);
>  	else
>  		value = -EINVAL;
> @@ -1185,7 +1185,7 @@ static ssize_t ffs_epfile_write_iter(struct kiocb *kiocb, struct iov_iter *from)
>  
>  	if (!is_sync_kiocb(kiocb)) {
>  		p = kzalloc(sizeof(io_data), GFP_KERNEL);
> -		if (unlikely(!p))
> +		if (!p)
>  			return -ENOMEM;
>  		p->aio = true;
>  	} else {
> @@ -1222,7 +1222,7 @@ static ssize_t ffs_epfile_read_iter(struct kiocb *kiocb, struct iov_iter *to)
>  
>  	if (!is_sync_kiocb(kiocb)) {
>  		p = kzalloc(sizeof(io_data), GFP_KERNEL);
> -		if (unlikely(!p))
> +		if (!p)
>  			return -ENOMEM;
>  		p->aio = true;
>  	} else {
> @@ -1384,7 +1384,7 @@ ffs_sb_make_inode(struct super_block *sb, void *data,
>  
>  	inode = new_inode(sb);
>  
> -	if (likely(inode)) {
> +	if (inode) {
>  		struct timespec64 ts = current_time(inode);
>  
>  		inode->i_ino	 = get_next_ino();
> @@ -1416,11 +1416,11 @@ static struct dentry *ffs_sb_create_file(struct super_block *sb,
>  	ENTER();
>  
>  	dentry = d_alloc_name(sb->s_root, name);
> -	if (unlikely(!dentry))
> +	if (!dentry)
>  		return NULL;
>  
>  	inode = ffs_sb_make_inode(sb, data, fops, NULL, &ffs->file_perms);
> -	if (unlikely(!inode)) {
> +	if (!inode) {
>  		dput(dentry);
>  		return NULL;
>  	}
> @@ -1467,12 +1467,11 @@ static int ffs_sb_fill(struct super_block *sb, struct fs_context *fc)
>  				  &simple_dir_inode_operations,
>  				  &data->perms);
>  	sb->s_root = d_make_root(inode);
> -	if (unlikely(!sb->s_root))
> +	if (!sb->s_root)
>  		return -ENOMEM;
>  
>  	/* EP0 file */
> -	if (unlikely(!ffs_sb_create_file(sb, "ep0", ffs,
> -					 &ffs_ep0_operations)))
> +	if (!ffs_sb_create_file(sb, "ep0", ffs, &ffs_ep0_operations))
>  		return -ENOMEM;
>  
>  	return 0;
> @@ -1560,13 +1559,13 @@ static int ffs_fs_get_tree(struct fs_context *fc)
>  		return invalf(fc, "No source specified");
>  
>  	ffs = ffs_data_new(fc->source);
> -	if (unlikely(!ffs))
> +	if (!ffs)
>  		return -ENOMEM;
>  	ffs->file_perms = ctx->perms;
>  	ffs->no_disconnect = ctx->no_disconnect;
>  
>  	ffs->dev_name = kstrdup(fc->source, GFP_KERNEL);
> -	if (unlikely(!ffs->dev_name)) {
> +	if (!ffs->dev_name) {
>  		ffs_data_put(ffs);
>  		return -ENOMEM;
>  	}
> @@ -1652,7 +1651,7 @@ static int functionfs_init(void)
>  	ENTER();
>  
>  	ret = register_filesystem(&ffs_fs_type);
> -	if (likely(!ret))
> +	if (!ret)
>  		pr_info("file system registered\n");
>  	else
>  		pr_err("failed registering file system (%d)\n", ret);
> @@ -1697,7 +1696,7 @@ static void ffs_data_put(struct ffs_data *ffs)
>  {
>  	ENTER();
>  
> -	if (unlikely(refcount_dec_and_test(&ffs->ref))) {
> +	if (refcount_dec_and_test(&ffs->ref)) {
>  		pr_info("%s(): freeing\n", __func__);
>  		ffs_data_clear(ffs);
>  		BUG_ON(waitqueue_active(&ffs->ev.waitq) ||
> @@ -1739,7 +1738,7 @@ static void ffs_data_closed(struct ffs_data *ffs)
>  static struct ffs_data *ffs_data_new(const char *dev_name)
>  {
>  	struct ffs_data *ffs = kzalloc(sizeof *ffs, GFP_KERNEL);
> -	if (unlikely(!ffs))
> +	if (!ffs)
>  		return NULL;
>  
>  	ENTER();
> @@ -1829,11 +1828,11 @@ static int functionfs_bind(struct ffs_data *ffs, struct usb_composite_dev *cdev)
>  		return -EBADFD;
>  
>  	first_id = usb_string_ids_n(cdev, ffs->strings_count);
> -	if (unlikely(first_id < 0))
> +	if (first_id < 0)
>  		return first_id;
>  
>  	ffs->ep0req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);
> -	if (unlikely(!ffs->ep0req))
> +	if (!ffs->ep0req)
>  		return -ENOMEM;
>  	ffs->ep0req->complete = ffs_ep0_complete;
>  	ffs->ep0req->context = ffs;
> @@ -1889,7 +1888,7 @@ static int ffs_epfiles_create(struct ffs_data *ffs)
>  		epfile->dentry = ffs_sb_create_file(ffs->sb, epfile->name,
>  						 epfile,
>  						 &ffs_epfile_operations);
> -		if (unlikely(!epfile->dentry)) {
> +		if (!epfile->dentry) {
>  			ffs_epfiles_destroy(epfiles, i - 1);
>  			return -ENOMEM;
>  		}
> @@ -1927,7 +1926,7 @@ static void ffs_func_eps_disable(struct ffs_function *func)
>  	spin_lock_irqsave(&func->ffs->eps_lock, flags);
>  	while (count--) {
>  		/* pending requests get nuked */
> -		if (likely(ep->ep))
> +		if (ep->ep)
>  			usb_ep_disable(ep->ep);
>  		++ep;
>  
> @@ -1961,7 +1960,7 @@ static int ffs_func_eps_enable(struct ffs_function *func)
>  		}
>  
>  		ret = usb_ep_enable(ep->ep);
> -		if (likely(!ret)) {
> +		if (!ret) {
>  			epfile->ep = ep;
>  			epfile->in = usb_endpoint_dir_in(ep->ep->desc);
>  			epfile->isoc = usb_endpoint_xfer_isoc(ep->ep->desc);
> @@ -2034,12 +2033,12 @@ static int __must_check ffs_do_single_desc(char *data, unsigned len,
>  #define __entity_check_ENDPOINT(val)   ((val) & USB_ENDPOINT_NUMBER_MASK)
>  #define __entity(type, val) do {					\
>  		pr_vdebug("entity " #type "(%02x)\n", (val));		\
> -		if (unlikely(!__entity_check_ ##type(val))) {		\
> +		if (!__entity_check_ ##type(val)) {			\
>  			pr_vdebug("invalid entity's value\n");		\
>  			return -EINVAL;					\
>  		}							\
>  		ret = entity(FFS_ ##type, &val, _ds, priv);		\
> -		if (unlikely(ret < 0)) {				\
> +		if (ret < 0) {						\
>  			pr_debug("entity " #type "(%02x); ret = %d\n",	\
>  				 (val), ret);				\
>  			return ret;					\
> @@ -2164,7 +2163,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
>  
>  		/* Record "descriptor" entity */
>  		ret = entity(FFS_DESCRIPTOR, (u8 *)num, (void *)data, priv);
> -		if (unlikely(ret < 0)) {
> +		if (ret < 0) {
>  			pr_debug("entity DESCRIPTOR(%02lx); ret = %d\n",
>  				 num, ret);
>  			return ret;
> @@ -2175,7 +2174,7 @@ static int __must_check ffs_do_descs(unsigned count, char *data, unsigned len,
>  
>  		ret = ffs_do_single_desc(data, len, entity, priv,
>  			&current_class);
> -		if (unlikely(ret < 0)) {
> +		if (ret < 0) {
>  			pr_debug("%s returns %d\n", __func__, ret);
>  			return ret;
>  		}
> @@ -2281,7 +2280,7 @@ static int __must_check ffs_do_single_os_desc(char *data, unsigned len,
>  	/* loop over all ext compat/ext prop descriptors */
>  	while (feature_count--) {
>  		ret = entity(type, h, data, len, priv);
> -		if (unlikely(ret < 0)) {
> +		if (ret < 0) {
>  			pr_debug("bad OS descriptor, type: %d\n", type);
>  			return ret;
>  		}
> @@ -2321,7 +2320,7 @@ static int __must_check ffs_do_os_descs(unsigned count,
>  			return -EINVAL;
>  
>  		ret = __ffs_do_os_desc_header(&type, desc);
> -		if (unlikely(ret < 0)) {
> +		if (ret < 0) {
>  			pr_debug("entity OS_DESCRIPTOR(%02lx); ret = %d\n",
>  				 num, ret);
>  			return ret;
> @@ -2342,7 +2341,7 @@ static int __must_check ffs_do_os_descs(unsigned count,
>  		 */
>  		ret = ffs_do_single_os_desc(data, len, type,
>  					    feature_count, entity, priv, desc);
> -		if (unlikely(ret < 0)) {
> +		if (ret < 0) {
>  			pr_debug("%s returns %d\n", __func__, ret);
>  			return ret;
>  		}
> @@ -2574,20 +2573,20 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  
>  	ENTER();
>  
> -	if (unlikely(len < 16 ||
> -		     get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
> -		     get_unaligned_le32(data + 4) != len))
> +	if (len < 16 ||
> +	    get_unaligned_le32(data) != FUNCTIONFS_STRINGS_MAGIC ||
> +	    get_unaligned_le32(data + 4) != len)
>  		goto error;
>  	str_count  = get_unaligned_le32(data + 8);
>  	lang_count = get_unaligned_le32(data + 12);
>  
>  	/* if one is zero the other must be zero */
> -	if (unlikely(!str_count != !lang_count))
> +	if (!str_count != !lang_count)
>  		goto error;
>  
>  	/* Do we have at least as many strings as descriptors need? */
>  	needed_count = ffs->strings_count;
> -	if (unlikely(str_count < needed_count))
> +	if (str_count < needed_count)
>  		goto error;
>  
>  	/*
> @@ -2611,7 +2610,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  
>  		char *vlabuf = kmalloc(vla_group_size(d), GFP_KERNEL);
>  
> -		if (unlikely(!vlabuf)) {
> +		if (!vlabuf) {
>  			kfree(_data);
>  			return -ENOMEM;
>  		}
> @@ -2638,7 +2637,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  	do { /* lang_count > 0 so we can use do-while */
>  		unsigned needed = needed_count;
>  
> -		if (unlikely(len < 3))
> +		if (len < 3)
>  			goto error_free;
>  		t->language = get_unaligned_le16(data);
>  		t->strings  = s;
> @@ -2651,7 +2650,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  		do { /* str_count > 0 so we can use do-while */
>  			size_t length = strnlen(data, len);
>  
> -			if (unlikely(length == len))
> +			if (length == len)
>  				goto error_free;
>  
>  			/*
> @@ -2659,7 +2658,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  			 * if that's the case we simply ignore the
>  			 * rest
>  			 */
> -			if (likely(needed)) {
> +			if (needed) {
>  				/*
>  				 * s->id will be set while adding
>  				 * function to configuration so for
> @@ -2681,7 +2680,7 @@ static int __ffs_data_got_strings(struct ffs_data *ffs,
>  	} while (--lang_count);
>  
>  	/* Some garbage left? */
> -	if (unlikely(len))
> +	if (len)
>  		goto error_free;
>  
>  	/* Done! */
> @@ -2828,7 +2827,7 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
>  
>  	ffs_ep = func->eps + idx;
>  
> -	if (unlikely(ffs_ep->descs[ep_desc_id])) {
> +	if (ffs_ep->descs[ep_desc_id]) {
>  		pr_err("two %sspeed descriptors for EP %d\n",
>  			  speed_names[ep_desc_id],
>  			  ds->bEndpointAddress & USB_ENDPOINT_NUMBER_MASK);
> @@ -2859,12 +2858,12 @@ static int __ffs_func_bind_do_descs(enum ffs_entity_type type, u8 *valuep,
>  		wMaxPacketSize = ds->wMaxPacketSize;
>  		pr_vdebug("autoconfig\n");
>  		ep = usb_ep_autoconfig(func->gadget, ds);
> -		if (unlikely(!ep))
> +		if (!ep)
>  			return -ENOTSUPP;
>  		ep->driver_data = func->eps + idx;
>  
>  		req = usb_ep_alloc_request(ep, GFP_KERNEL);
> -		if (unlikely(!req))
> +		if (!req)
>  			return -ENOMEM;
>  
>  		ffs_ep->ep  = ep;
> @@ -2906,7 +2905,7 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
>  		idx = *valuep;
>  		if (func->interfaces_nums[idx] < 0) {
>  			int id = usb_interface_id(func->conf, &func->function);
> -			if (unlikely(id < 0))
> +			if (id < 0)
>  				return id;
>  			func->interfaces_nums[idx] = id;
>  		}
> @@ -2927,7 +2926,7 @@ static int __ffs_func_bind_do_nums(enum ffs_entity_type type, u8 *valuep,
>  			return 0;
>  
>  		idx = (*valuep & USB_ENDPOINT_NUMBER_MASK) - 1;
> -		if (unlikely(!func->eps[idx].ep))
> +		if (!func->eps[idx].ep)
>  			return -EINVAL;
>  
>  		{
> @@ -3110,12 +3109,12 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  	ENTER();
>  
>  	/* Has descriptors only for speeds gadget does not support */
> -	if (unlikely(!(full | high | super)))
> +	if (!(full | high | super))
>  		return -ENOTSUPP;
>  
>  	/* Allocate a single chunk, less management later on */
>  	vlabuf = kzalloc(vla_group_size(d), GFP_KERNEL);
> -	if (unlikely(!vlabuf))
> +	if (!vlabuf)
>  		return -ENOMEM;
>  
>  	ffs->ms_os_descs_ext_prop_avail = vla_ptr(vlabuf, d, ext_prop);
> @@ -3144,13 +3143,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  	 * endpoints first, so that later we can rewrite the endpoint
>  	 * numbers without worrying that it may be described later on.
>  	 */
> -	if (likely(full)) {
> +	if (full) {
>  		func->function.fs_descriptors = vla_ptr(vlabuf, d, fs_descs);
>  		fs_len = ffs_do_descs(ffs->fs_descs_count,
>  				      vla_ptr(vlabuf, d, raw_descs),
>  				      d_raw_descs__sz,
>  				      __ffs_func_bind_do_descs, func);
> -		if (unlikely(fs_len < 0)) {
> +		if (fs_len < 0) {
>  			ret = fs_len;
>  			goto error;
>  		}
> @@ -3158,13 +3157,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  		fs_len = 0;
>  	}
>  
> -	if (likely(high)) {
> +	if (high) {
>  		func->function.hs_descriptors = vla_ptr(vlabuf, d, hs_descs);
>  		hs_len = ffs_do_descs(ffs->hs_descs_count,
>  				      vla_ptr(vlabuf, d, raw_descs) + fs_len,
>  				      d_raw_descs__sz - fs_len,
>  				      __ffs_func_bind_do_descs, func);
> -		if (unlikely(hs_len < 0)) {
> +		if (hs_len < 0) {
>  			ret = hs_len;
>  			goto error;
>  		}
> @@ -3172,13 +3171,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  		hs_len = 0;
>  	}
>  
> -	if (likely(super)) {
> +	if (super) {
>  		func->function.ss_descriptors = vla_ptr(vlabuf, d, ss_descs);
>  		ss_len = ffs_do_descs(ffs->ss_descs_count,
>  				vla_ptr(vlabuf, d, raw_descs) + fs_len + hs_len,
>  				d_raw_descs__sz - fs_len - hs_len,
>  				__ffs_func_bind_do_descs, func);
> -		if (unlikely(ss_len < 0)) {
> +		if (ss_len < 0) {
>  			ret = ss_len;
>  			goto error;
>  		}
> @@ -3196,7 +3195,7 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  			   (super ? ffs->ss_descs_count : 0),
>  			   vla_ptr(vlabuf, d, raw_descs), d_raw_descs__sz,
>  			   __ffs_func_bind_do_nums, func);
> -	if (unlikely(ret < 0))
> +	if (ret < 0)
>  		goto error;
>  
>  	func->function.os_desc_table = vla_ptr(vlabuf, d, os_desc_table);
> @@ -3217,13 +3216,13 @@ static int _ffs_func_bind(struct usb_configuration *c,
>  				      d_raw_descs__sz - fs_len - hs_len -
>  				      ss_len,
>  				      __ffs_func_bind_do_os_desc, func);
> -		if (unlikely(ret < 0))
> +		if (ret < 0)
>  			goto error;
>  	}
>  	func->function.os_desc_n =
>  		c->cdev->use_os_string ? ffs->interfaces_count : 0;
>  
> -	if (likely(super)) {
> +	if (super) {
>  		func->function.ssp_descriptors =
>  			usb_copy_descriptors(func->function.ss_descriptors);
>  	}
> @@ -3272,7 +3271,7 @@ static int ffs_func_set_alt(struct usb_function *f,
>  
>  	if (alt != (unsigned)-1) {
>  		intf = ffs_func_revmap_intf(func, interface);
> -		if (unlikely(intf < 0))
> +		if (intf < 0)
>  			return intf;
>  	}
>  
> @@ -3297,7 +3296,7 @@ static int ffs_func_set_alt(struct usb_function *f,
>  
>  	ffs->func = func;
>  	ret = ffs_func_eps_enable(func);
> -	if (likely(ret >= 0))
> +	if (ret >= 0)
>  		ffs_event_add(ffs, FUNCTIONFS_ENABLE);
>  	return ret;
>  }
> @@ -3339,13 +3338,13 @@ static int ffs_func_setup(struct usb_function *f,
>  	switch (creq->bRequestType & USB_RECIP_MASK) {
>  	case USB_RECIP_INTERFACE:
>  		ret = ffs_func_revmap_intf(func, le16_to_cpu(creq->wIndex));
> -		if (unlikely(ret < 0))
> +		if (ret < 0)
>  			return ret;
>  		break;
>  
>  	case USB_RECIP_ENDPOINT:
>  		ret = ffs_func_revmap_ep(func, le16_to_cpu(creq->wIndex));
> -		if (unlikely(ret < 0))
> +		if (ret < 0)
>  			return ret;
>  		if (func->ffs->user_flags & FUNCTIONFS_VIRTUAL_ADDR)
>  			ret = func->ffs->eps_addrmap[ret];
> @@ -3599,7 +3598,7 @@ static struct usb_function *ffs_alloc(struct usb_function_instance *fi)
>  	ENTER();
>  
>  	func = kzalloc(sizeof(*func), GFP_KERNEL);
> -	if (unlikely(!func))
> +	if (!func)
>  		return ERR_PTR(-ENOMEM);
>  
>  	func->function.name    = "Function FS Gadget";
> @@ -3814,7 +3813,7 @@ static void ffs_closed(struct ffs_data *ffs)
>  static int ffs_mutex_lock(struct mutex *mutex, unsigned nonblock)
>  {
>  	return nonblock
> -		? likely(mutex_trylock(mutex)) ? 0 : -EAGAIN
> +		? mutex_trylock(mutex) ? 0 : -EAGAIN
>  		: mutex_lock_interruptible(mutex);
>  }
>  
> @@ -3822,14 +3821,14 @@ static char *ffs_prepare_buffer(const char __user *buf, size_t len)
>  {
>  	char *data;
>  
> -	if (unlikely(!len))
> +	if (!len)
>  		return NULL;
>  
>  	data = kmalloc(len, GFP_KERNEL);
> -	if (unlikely(!data))
> +	if (!data)
>  		return ERR_PTR(-ENOMEM);
>  
> -	if (unlikely(copy_from_user(data, buf, len))) {
> +	if (copy_from_user(data, buf, len)) {
>  		kfree(data);
>  		return ERR_PTR(-EFAULT);
>  	}
> -- 
> 2.29.2
> 

-- 

Thanks,
Peter Chen