| Message ID | 20231201-pxrc-guard-v1-1-38937e657368@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Input: pxrc - simplify mutex handling with guard macro | expand |
On Fri, Dec 01, 2023 at 01:08:45PM +0100, Marcus Folkesson wrote: > Use the guard(mutex) macro for handle mutex lock/unlocks. > > Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> A couple of drive-by comments below. > --- > drivers/input/joystick/pxrc.c | 27 +++++++++++---------------- > 1 file changed, 11 insertions(+), 16 deletions(-) > > diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c > index ea2bf5951d67..3c3bf7179b46 100644 > --- a/drivers/input/joystick/pxrc.c > +++ b/drivers/input/joystick/pxrc.c > @@ -5,15 +5,17 @@ > * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com> > */ > > -#include <linux/kernel.h> > +#include <linux/cleanup.h> > #include <linux/errno.h> > -#include <linux/slab.h> > +#include <linux/input.h> > +#include <linux/kernel.h> > #include <linux/module.h> > +#include <linux/mutex.h> > +#include <linux/slab.h> > #include <linux/uaccess.h> > + > #include <linux/usb.h> > #include <linux/usb/input.h> > -#include <linux/mutex.h> > -#include <linux/input.h> Looks like an unrelated change. > #define PXRC_VENDOR_ID 0x1781 > #define PXRC_PRODUCT_ID 0x0898 > @@ -89,25 +91,20 @@ static int pxrc_open(struct input_dev *input) > dev_err(&pxrc->intf->dev, > "%s - usb_submit_urb failed, error: %d\n", > __func__, retval); > - retval = -EIO; > - goto out; > + return -EIO; > } > > pxrc->is_open = true; > - > -out: > - mutex_unlock(&pxrc->pm_mutex); > - return retval; > + return 0; > } Eh, this looks obviously broken. Did you not test this before submitting? I assume lockdep would complain loudly too. You're apparently the author of this driver and can test it, but I fear the coming onslaught of untested guard conversions from the "cleanup" crew. Not sure I find the result generally more readable either. Johan
On Fri, Dec 01, 2023 at 02:29:22PM +0100, Johan Hovold wrote: > On Fri, Dec 01, 2023 at 01:08:45PM +0100, Marcus Folkesson wrote: > > Use the guard(mutex) macro for handle mutex lock/unlocks. > > > > Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> > > A couple of drive-by comments below. > > > --- > > drivers/input/joystick/pxrc.c | 27 +++++++++++---------------- > > 1 file changed, 11 insertions(+), 16 deletions(-) > > > > diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c > > index ea2bf5951d67..3c3bf7179b46 100644 > > --- a/drivers/input/joystick/pxrc.c > > +++ b/drivers/input/joystick/pxrc.c > > @@ -5,15 +5,17 @@ > > * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com> > > */ > > > > -#include <linux/kernel.h> > > +#include <linux/cleanup.h> > > #include <linux/errno.h> > > -#include <linux/slab.h> > > +#include <linux/input.h> > > +#include <linux/kernel.h> > > #include <linux/module.h> > > +#include <linux/mutex.h> > > +#include <linux/slab.h> > > #include <linux/uaccess.h> > > + > > #include <linux/usb.h> > > #include <linux/usb/input.h> > > -#include <linux/mutex.h> > > -#include <linux/input.h> > > Looks like an unrelated change. I reordered the include files as I added cleanup.h. I can do it in a separate patch if that is preferred. > > > #define PXRC_VENDOR_ID 0x1781 > > #define PXRC_PRODUCT_ID 0x0898 > > @@ -89,25 +91,20 @@ static int pxrc_open(struct input_dev *input) > > dev_err(&pxrc->intf->dev, > > "%s - usb_submit_urb failed, error: %d\n", > > __func__, retval); > > - retval = -EIO; > > - goto out; > > + return -EIO; > > } > > > > pxrc->is_open = true; > > - > > -out: > > - mutex_unlock(&pxrc->pm_mutex); > > - return retval; > > + return 0; > > } > > Eh, this looks obviously broken. Did you not test this before > submitting? I assume lockdep would complain loudly too. Sorry, it is more that I'm not in the habit of using b4 for submitting patches yet, so things got wrong. There is a v2 out there. The driver (v2) is quickly tested on HW and, what I can tell, seems to behave. > > You're apparently the author of this driver and can test it, but I fear > the coming onslaught of untested guard conversions from the "cleanup" > crew. Not sure I find the result generally more readable either. > > Johan Best regards Marcus Folkesson
On Fri, Dec 01, 2023 at 02:48:06PM +0100, Marcus Folkesson wrote: > On Fri, Dec 01, 2023 at 02:29:22PM +0100, Johan Hovold wrote: > > Eh, this looks obviously broken. Did you not test this before > > submitting? I assume lockdep would complain loudly too. > > Sorry, it is more that I'm not in the habit of using b4 for submitting > patches yet, so things got wrong. > There is a v2 out there. Ah, good, you noticed yourself. Johan
On Fri, Dec 01, 2023 at 02:29:22PM +0100, Johan Hovold wrote: > On Fri, Dec 01, 2023 at 01:08:45PM +0100, Marcus Folkesson wrote: > > Use the guard(mutex) macro for handle mutex lock/unlocks. > > > > Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> > > A couple of drive-by comments below. > > > --- > > drivers/input/joystick/pxrc.c | 27 +++++++++++---------------- > > 1 file changed, 11 insertions(+), 16 deletions(-) > > > > diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c > > index ea2bf5951d67..3c3bf7179b46 100644 > > --- a/drivers/input/joystick/pxrc.c > > +++ b/drivers/input/joystick/pxrc.c > > @@ -5,15 +5,17 @@ > > * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com> > > */ > > > > -#include <linux/kernel.h> > > +#include <linux/cleanup.h> > > #include <linux/errno.h> > > -#include <linux/slab.h> > > +#include <linux/input.h> > > +#include <linux/kernel.h> > > #include <linux/module.h> > > +#include <linux/mutex.h> > > +#include <linux/slab.h> > > #include <linux/uaccess.h> > > + > > #include <linux/usb.h> > > #include <linux/usb/input.h> > > -#include <linux/mutex.h> > > -#include <linux/input.h> > > Looks like an unrelated change. > > > #define PXRC_VENDOR_ID 0x1781 > > #define PXRC_PRODUCT_ID 0x0898 > > @@ -89,25 +91,20 @@ static int pxrc_open(struct input_dev *input) > > dev_err(&pxrc->intf->dev, > > "%s - usb_submit_urb failed, error: %d\n", > > __func__, retval); > > - retval = -EIO; > > - goto out; > > + return -EIO; > > } > > > > pxrc->is_open = true; > > - > > -out: > > - mutex_unlock(&pxrc->pm_mutex); > > - return retval; > > + return 0; > > } > > Eh, this looks obviously broken. Did you not test this before > submitting? I assume lockdep would complain loudly too. > > You're apparently the author of this driver and can test it, but I fear > the coming onslaught of untested guard conversions from the "cleanup" > crew. Not sure I find the result generally more readable either. Yeah, for the code without conditions (like pxrc_close) the utility is questionable, but I guess it is just a matter of getting used to the new facilities... Thanks.
diff --git a/drivers/input/joystick/pxrc.c b/drivers/input/joystick/pxrc.c index ea2bf5951d67..3c3bf7179b46 100644 --- a/drivers/input/joystick/pxrc.c +++ b/drivers/input/joystick/pxrc.c @@ -5,15 +5,17 @@ * Copyright (C) 2018 Marcus Folkesson <marcus.folkesson@gmail.com> */ -#include <linux/kernel.h> +#include <linux/cleanup.h> #include <linux/errno.h> -#include <linux/slab.h> +#include <linux/input.h> +#include <linux/kernel.h> #include <linux/module.h> +#include <linux/mutex.h> +#include <linux/slab.h> #include <linux/uaccess.h> + #include <linux/usb.h> #include <linux/usb/input.h> -#include <linux/mutex.h> -#include <linux/input.h> #define PXRC_VENDOR_ID 0x1781 #define PXRC_PRODUCT_ID 0x0898 @@ -89,25 +91,20 @@ static int pxrc_open(struct input_dev *input) dev_err(&pxrc->intf->dev, "%s - usb_submit_urb failed, error: %d\n", __func__, retval); - retval = -EIO; - goto out; + return -EIO; } pxrc->is_open = true; - -out: - mutex_unlock(&pxrc->pm_mutex); - return retval; + return 0; } static void pxrc_close(struct input_dev *input) { struct pxrc *pxrc = input_get_drvdata(input); - mutex_lock(&pxrc->pm_mutex); + guard(mutex)(&pxrc->pm_mutex); usb_kill_urb(pxrc->urb); pxrc->is_open = false; - mutex_unlock(&pxrc->pm_mutex); } static void pxrc_free_urb(void *_pxrc) @@ -208,10 +205,9 @@ static int pxrc_suspend(struct usb_interface *intf, pm_message_t message) { struct pxrc *pxrc = usb_get_intfdata(intf); - mutex_lock(&pxrc->pm_mutex); + guard(mutex)(&pxrc->pm_mutex); if (pxrc->is_open) usb_kill_urb(pxrc->urb); - mutex_unlock(&pxrc->pm_mutex); return 0; } @@ -221,11 +217,10 @@ static int pxrc_resume(struct usb_interface *intf) struct pxrc *pxrc = usb_get_intfdata(intf); int retval = 0; - mutex_lock(&pxrc->pm_mutex); + guard(mutex)(&pxrc->pm_mutex); if (pxrc->is_open && usb_submit_urb(pxrc->urb, GFP_KERNEL) < 0) retval = -EIO; - mutex_unlock(&pxrc->pm_mutex); return retval; }
Use the guard(mutex) macro for handle mutex lock/unlocks. Signed-off-by: Marcus Folkesson <marcus.folkesson@gmail.com> --- drivers/input/joystick/pxrc.c | 27 +++++++++++---------------- 1 file changed, 11 insertions(+), 16 deletions(-) --- base-commit: ffc253263a1375a65fa6c9f62a893e9767fbebfa change-id: 20231201-pxrc-guard-03dc35771b36 Best regards,