2024-01-26 12:53:48

by tip-bot2 for Jacob Pan

[permalink] [raw]
Subject: [tip: irq/core] genirq/irq_sim: Shrink code by using cleanup helpers

The following commit has been merged into the irq/core branch of tip:

Commit-ID: 590610d72a790458431cbbebc71ee24521533b5e
Gitweb: https://git.kernel.org/tip/590610d72a790458431cbbebc71ee24521533b5e
Author: Bartosz Golaszewski <[email protected]>
AuthorDate: Mon, 22 Jan 2024 13:42:43 +01:00
Committer: Thomas Gleixner <[email protected]>
CommitterDate: Fri, 26 Jan 2024 13:44:48 +01:00

genirq/irq_sim: Shrink code by using cleanup helpers

Use the new __free() mechanism to remove all gotos and simplify the error
paths.

Signed-off-by: Bartosz Golaszewski <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

---
kernel/irq/irq_sim.c | 25 ++++++++++---------------
1 file changed, 10 insertions(+), 15 deletions(-)

diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index b0d50b4..fe8fd30 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -4,6 +4,7 @@
* Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
*/

+#include <linux/cleanup.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irq_sim.h>
@@ -163,33 +164,27 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
unsigned int num_irqs)
{
- struct irq_sim_work_ctx *work_ctx;
+ struct irq_sim_work_ctx *work_ctx __free(kfree) = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
+ unsigned long *pending;

- work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
if (!work_ctx)
- goto err_out;
+ return ERR_PTR(-ENOMEM);

- work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
- if (!work_ctx->pending)
- goto err_free_work_ctx;
+ pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
+ if (!pending)
+ return ERR_PTR(-ENOMEM);

work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
&irq_sim_domain_ops,
work_ctx);
if (!work_ctx->domain)
- goto err_free_bitmap;
+ return ERR_PTR(-ENOMEM);

work_ctx->irq_count = num_irqs;
work_ctx->work = IRQ_WORK_INIT_HARD(irq_sim_handle_irq);
+ work_ctx->pending = no_free_ptr(pending);

- return work_ctx->domain;
-
-err_free_bitmap:
- bitmap_free(work_ctx->pending);
-err_free_work_ctx:
- kfree(work_ctx);
-err_out:
- return ERR_PTR(-ENOMEM);
+ return no_free_ptr(work_ctx)->domain;
}
EXPORT_SYMBOL_GPL(irq_domain_create_sim);



2024-01-26 21:05:20

by Nathan Chancellor

[permalink] [raw]
Subject: Re: [tip: irq/core] genirq/irq_sim: Shrink code by using cleanup helpers

On Fri, Jan 26, 2024 at 12:53:36PM -0000, tip-bot2 for Bartosz Golaszewski wrote:
> The following commit has been merged into the irq/core branch of tip:
>
> Commit-ID: 590610d72a790458431cbbebc71ee24521533b5e
> Gitweb: https://git.kernel.org/tip/590610d72a790458431cbbebc71ee24521533b5e
> Author: Bartosz Golaszewski <[email protected]>
> AuthorDate: Mon, 22 Jan 2024 13:42:43 +01:00
> Committer: Thomas Gleixner <[email protected]>
> CommitterDate: Fri, 26 Jan 2024 13:44:48 +01:00
>
> genirq/irq_sim: Shrink code by using cleanup helpers
>
> Use the new __free() mechanism to remove all gotos and simplify the error
> paths.
>
> Signed-off-by: Bartosz Golaszewski <[email protected]>
> Signed-off-by: Thomas Gleixner <[email protected]>
> Link: https://lore.kernel.org/r/[email protected]
>
> ---
> kernel/irq/irq_sim.c | 25 ++++++++++---------------
> 1 file changed, 10 insertions(+), 15 deletions(-)
>
> diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> index b0d50b4..fe8fd30 100644
> --- a/kernel/irq/irq_sim.c
> +++ b/kernel/irq/irq_sim.c
> @@ -4,6 +4,7 @@
> * Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
> */
>
> +#include <linux/cleanup.h>
> #include <linux/interrupt.h>
> #include <linux/irq.h>
> #include <linux/irq_sim.h>
> @@ -163,33 +164,27 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
> struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
> unsigned int num_irqs)
> {
> - struct irq_sim_work_ctx *work_ctx;
> + struct irq_sim_work_ctx *work_ctx __free(kfree) = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> + unsigned long *pending;
>
> - work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> if (!work_ctx)
> - goto err_out;
> + return ERR_PTR(-ENOMEM);
>
> - work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> - if (!work_ctx->pending)
> - goto err_free_work_ctx;
> + pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);

Apologies if this has already been reported elsewhere. This does not
match what was sent and it causes the build to break with both GCC:

In file included from include/linux/compiler_types.h:89,
from <command-line>:
kernel/irq/irq_sim.c: In function 'irq_domain_create_sim':
include/linux/compiler_attributes.h:76:41: error: expected expression before '__attribute__'
76 | #define __cleanup(func) __attribute__((__cleanup__(func)))
| ^~~~~~~~~~~~~
include/linux/cleanup.h:64:25: note: in expansion of macro '__cleanup'
64 | #define __free(_name) __cleanup(__free_##_name)
| ^~~~~~~~~
kernel/irq/irq_sim.c:173:19: note: in expansion of macro '__free'
173 | pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
| ^~~~~~

and Clang:

kernel/irq/irq_sim.c:173:12: error: expected expression
173 | pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
| ^
include/linux/cleanup.h:64:23: note: expanded from macro '__free'
64 | #define __free(_name) __cleanup(__free_##_name)
| ^
include/linux/compiler-clang.h:15:25: note: expanded from macro '__cleanup'
15 | #define __cleanup(func) __maybe_unused __attribute__((__cleanup__(func)))
| ^
include/linux/compiler_attributes.h:344:41: note: expanded from macro '__maybe_unused'
344 | #define __maybe_unused __attribute__((__unused__))
| ^
1 error generated.

This was initially noticed by our CI:

https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/7671789235/job/20915505965
https://storage.tuxsuite.com/public/clangbuiltlinux/continuous-integration2/builds/2bVGKZUmat8fRr582Nh8hNA6FXD/build.log

Cheers,
Nathan

> + if (!pending)
> + return ERR_PTR(-ENOMEM);
>
> work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
> &irq_sim_domain_ops,
> work_ctx);
> if (!work_ctx->domain)
> - goto err_free_bitmap;
> + return ERR_PTR(-ENOMEM);
>
> work_ctx->irq_count = num_irqs;
> work_ctx->work = IRQ_WORK_INIT_HARD(irq_sim_handle_irq);
> + work_ctx->pending = no_free_ptr(pending);
>
> - return work_ctx->domain;
> -
> -err_free_bitmap:
> - bitmap_free(work_ctx->pending);
> -err_free_work_ctx:
> - kfree(work_ctx);
> -err_out:
> - return ERR_PTR(-ENOMEM);
> + return no_free_ptr(work_ctx)->domain;
> }
> EXPORT_SYMBOL_GPL(irq_domain_create_sim);
>

2024-01-26 22:24:42

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [tip: irq/core] genirq/irq_sim: Shrink code by using cleanup helpers

On Fri, 26 Jan 2024 at 22:05, Nathan Chancellor <[email protected]> wrote:
>
> On Fri, Jan 26, 2024 at 12:53:36PM -0000, tip-bot2 for Bartosz Golaszewski wrote:
> > The following commit has been merged into the irq/core branch of tip:
> >
> > Commit-ID: 590610d72a790458431cbbebc71ee24521533b5e
> > Gitweb: https://git.kernel.org/tip/590610d72a790458431cbbebc71ee24521533b5e
> > Author: Bartosz Golaszewski <[email protected]>
> > AuthorDate: Mon, 22 Jan 2024 13:42:43 +01:00
> > Committer: Thomas Gleixner <[email protected]>
> > CommitterDate: Fri, 26 Jan 2024 13:44:48 +01:00
> >
> > genirq/irq_sim: Shrink code by using cleanup helpers
> >
> > Use the new __free() mechanism to remove all gotos and simplify the error
> > paths.
> >
> > Signed-off-by: Bartosz Golaszewski <[email protected]>
> > Signed-off-by: Thomas Gleixner <[email protected]>
> > Link: https://lore.kernel.org/r/[email protected]
> >
> > ---
> > kernel/irq/irq_sim.c | 25 ++++++++++---------------
> > 1 file changed, 10 insertions(+), 15 deletions(-)
> >
> > diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> > index b0d50b4..fe8fd30 100644
> > --- a/kernel/irq/irq_sim.c
> > +++ b/kernel/irq/irq_sim.c
> > @@ -4,6 +4,7 @@
> > * Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
> > */
> >
> > +#include <linux/cleanup.h>
> > #include <linux/interrupt.h>
> > #include <linux/irq.h>
> > #include <linux/irq_sim.h>
> > @@ -163,33 +164,27 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
> > struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
> > unsigned int num_irqs)
> > {
> > - struct irq_sim_work_ctx *work_ctx;
> > + struct irq_sim_work_ctx *work_ctx __free(kfree) = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > + unsigned long *pending;
> >
> > - work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > if (!work_ctx)
> > - goto err_out;
> > + return ERR_PTR(-ENOMEM);
> >
> > - work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> > - if (!work_ctx->pending)
> > - goto err_free_work_ctx;
> > + pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
>
> Apologies if this has already been reported elsewhere. This does not
> match what was sent and it causes the build to break with both GCC:
>

I did not see any other report. I don't know what happened here but
this was a ninja edit as it's not what I sent. If Thomas' intention
was to move the variable declaration and detach it from the assignment
then 'pending' should at least be set to NULL and __free() must
decorate the declaration.

But the coding style of declaring variables when they're first
assigned their auto-cleaned value is what Linus Torvalds explicitly
asked me to do when I first started sending PRs containing uses of
linux/cleanup.h.

Bartosz

> In file included from include/linux/compiler_types.h:89,
> from <command-line>:
> kernel/irq/irq_sim.c: In function 'irq_domain_create_sim':
> include/linux/compiler_attributes.h:76:41: error: expected expression before '__attribute__'
> 76 | #define __cleanup(func) __attribute__((__cleanup__(func)))
> | ^~~~~~~~~~~~~
> include/linux/cleanup.h:64:25: note: in expansion of macro '__cleanup'
> 64 | #define __free(_name) __cleanup(__free_##_name)
> | ^~~~~~~~~
> kernel/irq/irq_sim.c:173:19: note: in expansion of macro '__free'
> 173 | pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
> | ^~~~~~
>
> and Clang:
>
> kernel/irq/irq_sim.c:173:12: error: expected expression
> 173 | pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
> | ^
> include/linux/cleanup.h:64:23: note: expanded from macro '__free'
> 64 | #define __free(_name) __cleanup(__free_##_name)
> | ^
> include/linux/compiler-clang.h:15:25: note: expanded from macro '__cleanup'
> 15 | #define __cleanup(func) __maybe_unused __attribute__((__cleanup__(func)))
> | ^
> include/linux/compiler_attributes.h:344:41: note: expanded from macro '__maybe_unused'
> 344 | #define __maybe_unused __attribute__((__unused__))
> | ^
> 1 error generated.
>
> This was initially noticed by our CI:
>
> https://github.com/ClangBuiltLinux/continuous-integration2/actions/runs/7671789235/job/20915505965
> https://storage.tuxsuite.com/public/clangbuiltlinux/continuous-integration2/builds/2bVGKZUmat8fRr582Nh8hNA6FXD/build.log
>
> Cheers,
> Nathan
>
> > + if (!pending)
> > + return ERR_PTR(-ENOMEM);
> >
> > work_ctx->domain = irq_domain_create_linear(fwnode, num_irqs,
> > &irq_sim_domain_ops,
> > work_ctx);
> > if (!work_ctx->domain)
> > - goto err_free_bitmap;
> > + return ERR_PTR(-ENOMEM);
> >
> > work_ctx->irq_count = num_irqs;
> > work_ctx->work = IRQ_WORK_INIT_HARD(irq_sim_handle_irq);
> > + work_ctx->pending = no_free_ptr(pending);
> >
> > - return work_ctx->domain;
> > -
> > -err_free_bitmap:
> > - bitmap_free(work_ctx->pending);
> > -err_free_work_ctx:
> > - kfree(work_ctx);
> > -err_out:
> > - return ERR_PTR(-ENOMEM);
> > + return no_free_ptr(work_ctx)->domain;
> > }
> > EXPORT_SYMBOL_GPL(irq_domain_create_sim);
> >

2024-01-29 10:13:14

by Ingo Molnar

[permalink] [raw]
Subject: Re: [tip: irq/core] genirq/irq_sim: Shrink code by using cleanup helpers


* Bartosz Golaszewski <[email protected]> wrote:

> On Fri, 26 Jan 2024 at 22:05, Nathan Chancellor <[email protected]> wrote:
> >
> > > Committer: Thomas Gleixner <[email protected]>
> > > CommitterDate: Fri, 26 Jan 2024 13:44:48 +01:00
> > >
> > > genirq/irq_sim: Shrink code by using cleanup helpers
> > >
> > > Use the new __free() mechanism to remove all gotos and simplify the error
> > > paths.
> > >
> > > Signed-off-by: Bartosz Golaszewski <[email protected]>
> > > Signed-off-by: Thomas Gleixner <[email protected]>
> > > Link: https://lore.kernel.org/r/[email protected]
> > >
> > > ---
> > > kernel/irq/irq_sim.c | 25 ++++++++++---------------
> > > 1 file changed, 10 insertions(+), 15 deletions(-)
> > >
> > > diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> > > index b0d50b4..fe8fd30 100644
> > > --- a/kernel/irq/irq_sim.c
> > > +++ b/kernel/irq/irq_sim.c
> > > @@ -4,6 +4,7 @@
> > > * Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
> > > */
> > >
> > > +#include <linux/cleanup.h>
> > > #include <linux/interrupt.h>
> > > #include <linux/irq.h>
> > > #include <linux/irq_sim.h>
> > > @@ -163,33 +164,27 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
> > > struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
> > > unsigned int num_irqs)
> > > {
> > > - struct irq_sim_work_ctx *work_ctx;
> > > + struct irq_sim_work_ctx *work_ctx __free(kfree) = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > > + unsigned long *pending;
> > >
> > > - work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > > if (!work_ctx)
> > > - goto err_out;
> > > + return ERR_PTR(-ENOMEM);
> > >
> > > - work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> > > - if (!work_ctx->pending)
> > > - goto err_free_work_ctx;
> > > + pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
> >
> > Apologies if this has already been reported elsewhere. This does not
> > match what was sent and it causes the build to break with both GCC:
> >
>
> I did not see any other report. I don't know what happened here but
> this was a ninja edit as it's not what I sent. If Thomas' intention
> was to move the variable declaration and detach it from the assignment
> then 'pending' should at least be set to NULL and __free() must
> decorate the declaration.
>
> But the coding style of declaring variables when they're first
> assigned their auto-cleaned value is what Linus Torvalds explicitly
> asked me to do when I first started sending PRs containing uses of
> linux/cleanup.h.

Ok - I've rebased tip:irq/core with the original patch.

Do you have a reference to Linus's mail about C++ style definition
of variables? I can see the validity of the pattern in this context,
but it's explicitly against the kernel coding style AFAICS, which
I suppose prompted Thomas's edit. I'd like to have an URL handy when the
inevitable checkpatch 'fix' gets submitted. ;-)

Thanks,

Ingo

2024-01-29 10:37:58

by Bartosz Golaszewski

[permalink] [raw]
Subject: Re: [tip: irq/core] genirq/irq_sim: Shrink code by using cleanup helpers

On Mon, 29 Jan 2024 at 11:13, Ingo Molnar <[email protected]> wrote:
>
>
> * Bartosz Golaszewski <[email protected]> wrote:
>
> > On Fri, 26 Jan 2024 at 22:05, Nathan Chancellor <[email protected]> wrote:
> > >
> > > > Committer: Thomas Gleixner <[email protected]>
> > > > CommitterDate: Fri, 26 Jan 2024 13:44:48 +01:00
> > > >
> > > > genirq/irq_sim: Shrink code by using cleanup helpers
> > > >
> > > > Use the new __free() mechanism to remove all gotos and simplify the error
> > > > paths.
> > > >
> > > > Signed-off-by: Bartosz Golaszewski <[email protected]>
> > > > Signed-off-by: Thomas Gleixner <[email protected]>
> > > > Link: https://lore.kernel.org/r/[email protected]
> > > >
> > > > ---
> > > > kernel/irq/irq_sim.c | 25 ++++++++++---------------
> > > > 1 file changed, 10 insertions(+), 15 deletions(-)
> > > >
> > > > diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
> > > > index b0d50b4..fe8fd30 100644
> > > > --- a/kernel/irq/irq_sim.c
> > > > +++ b/kernel/irq/irq_sim.c
> > > > @@ -4,6 +4,7 @@
> > > > * Copyright (C) 2020 Bartosz Golaszewski <[email protected]>
> > > > */
> > > >
> > > > +#include <linux/cleanup.h>
> > > > #include <linux/interrupt.h>
> > > > #include <linux/irq.h>
> > > > #include <linux/irq_sim.h>
> > > > @@ -163,33 +164,27 @@ static const struct irq_domain_ops irq_sim_domain_ops = {
> > > > struct irq_domain *irq_domain_create_sim(struct fwnode_handle *fwnode,
> > > > unsigned int num_irqs)
> > > > {
> > > > - struct irq_sim_work_ctx *work_ctx;
> > > > + struct irq_sim_work_ctx *work_ctx __free(kfree) = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > > > + unsigned long *pending;
> > > >
> > > > - work_ctx = kmalloc(sizeof(*work_ctx), GFP_KERNEL);
> > > > if (!work_ctx)
> > > > - goto err_out;
> > > > + return ERR_PTR(-ENOMEM);
> > > >
> > > > - work_ctx->pending = bitmap_zalloc(num_irqs, GFP_KERNEL);
> > > > - if (!work_ctx->pending)
> > > > - goto err_free_work_ctx;
> > > > + pending = __free(bitmap) = bitmap_zalloc(num_irqs, GFP_KERNEL);
> > >
> > > Apologies if this has already been reported elsewhere. This does not
> > > match what was sent and it causes the build to break with both GCC:
> > >
> >
> > I did not see any other report. I don't know what happened here but
> > this was a ninja edit as it's not what I sent. If Thomas' intention
> > was to move the variable declaration and detach it from the assignment
> > then 'pending' should at least be set to NULL and __free() must
> > decorate the declaration.
> >
> > But the coding style of declaring variables when they're first
> > assigned their auto-cleaned value is what Linus Torvalds explicitly
> > asked me to do when I first started sending PRs containing uses of
> > linux/cleanup.h.
>
> Ok - I've rebased tip:irq/core with the original patch.
>
> Do you have a reference to Linus's mail about C++ style definition
> of variables? I can see the validity of the pattern in this context,
> but it's explicitly against the kernel coding style AFAICS, which
> I suppose prompted Thomas's edit. I'd like to have an URL handy when the
> inevitable checkpatch 'fix' gets submitted. ;-)
>

Sure, here's one rant I was the target of:
https://lore.kernel.org/all/CAHk-=wgRHiV5VSxtfXA4S6aLUmcQYEuB67u3BJPJPtuESs1JyA@mail.gmail.com/

Bartosz