| Message ID | 1396004735-15475-2-git-send-email-ard.biesheuvel@linaro.org |
|---|---|
| State | New |
| Headers | show |
On Fri, 28 Mar 2014, Ard Biesheuvel wrote: > This adds arch/arm64/crypto/preempt.h, currently containing just a single > asm macro definition 'b_if_no_resched' that will be shared between multiple > crypto algorithm implementations that need to test for preemption in the > inner loop. This file is a rather bad choice for this pretty generic macro. There is nothing crypto specific about it, even if crypto might be the only user for now. This should live in include/asm/assembler.h, or a separate file in that directory only if including <asm/asm-offsets.h> from assembler.h is considered a nuisance. > > Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> > --- > arch/arm64/crypto/preempt.h | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) > create mode 100644 arch/arm64/crypto/preempt.h > > diff --git a/arch/arm64/crypto/preempt.h b/arch/arm64/crypto/preempt.h > new file mode 100644 > index 000000000000..94302d5b5ae9 > --- /dev/null > +++ b/arch/arm64/crypto/preempt.h > @@ -0,0 +1,28 @@ > +/* > + * preempt.h - shared macros to check preempt state > + * > + * Copyright (C) 2014 Linaro Ltd <ard.biesheuvel@linaro.org> > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License version 2 as > + * published by the Free Software Foundation. > + */ > + > +#include <asm/asm-offsets.h> > +#include <asm/thread_info.h> > + > + /* > + * Branch to 'lb' but only if we have not been tagged for preemption. > + * > + * Expects current->thread_info in ti, or NULL if running in interrupt > + * context. reg is a scratch x register. > + */ > + .macro b_if_no_resched, ti, reg, lb > +#if defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY) > + cbz \ti, \lb // have thread_info? > + ldr \reg, [\ti, #TI_FLAGS] // get flags > + tbz \reg, #TIF_NEED_RESCHED, \lb // needs rescheduling? > +#else > + b \lb > +#endif > + .endm > -- > 1.8.3.2 > > > _______________________________________________ > linux-arm-kernel mailing list > linux-arm-kernel@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/linux-arm-kernel >
On 29 March 2014 02:53, Nicolas Pitre <nicolas.pitre@linaro.org> wrote: > On Fri, 28 Mar 2014, Ard Biesheuvel wrote: > >> This adds arch/arm64/crypto/preempt.h, currently containing just a single >> asm macro definition 'b_if_no_resched' that will be shared between multiple >> crypto algorithm implementations that need to test for preemption in the >> inner loop. > > This file is a rather bad choice for this pretty generic macro. There > is nothing crypto specific about it, even if crypto might be the only > user for now. This should live in include/asm/assembler.h, or a > separate file in that directory only if including <asm/asm-offsets.h> > from assembler.h is considered a nuisance. > True, there is nothing crypto specific about it, @Catalin: would you object to adding this macro (and the #include asm-offsets.h) to assembler.h? Or would you prefer to have it in a separate file?
diff --git a/arch/arm64/crypto/preempt.h b/arch/arm64/crypto/preempt.h new file mode 100644 index 000000000000..94302d5b5ae9 --- /dev/null +++ b/arch/arm64/crypto/preempt.h @@ -0,0 +1,28 @@ +/* + * preempt.h - shared macros to check preempt state + * + * Copyright (C) 2014 Linaro Ltd <ard.biesheuvel@linaro.org> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include <asm/asm-offsets.h> +#include <asm/thread_info.h> + + /* + * Branch to 'lb' but only if we have not been tagged for preemption. + * + * Expects current->thread_info in ti, or NULL if running in interrupt + * context. reg is a scratch x register. + */ + .macro b_if_no_resched, ti, reg, lb +#if defined(CONFIG_PREEMPT) || defined(CONFIG_PREEMPT_VOLUNTARY) + cbz \ti, \lb // have thread_info? + ldr \reg, [\ti, #TI_FLAGS] // get flags + tbz \reg, #TIF_NEED_RESCHED, \lb // needs rescheduling? +#else + b \lb +#endif + .endm
This adds arch/arm64/crypto/preempt.h, currently containing just a single asm macro definition 'b_if_no_resched' that will be shared between multiple crypto algorithm implementations that need to test for preemption in the inner loop. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> --- arch/arm64/crypto/preempt.h | 28 ++++++++++++++++++++++++++++ 1 file changed, 28 insertions(+) create mode 100644 arch/arm64/crypto/preempt.h