| Message ID | 2589612a53a9e9feb67b8e8286e87893359676d1.1740499185.git.jerome.forissier@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Uthreads | expand |
Hi Jerome, On Tue, 25 Feb 2025 at 18:35, Jerome Forissier <jerome.forissier@linaro.org> wrote: > > HAVE_INIJMP will be set by architectures that support initjmp(), a > non-standard extension to setjmp()/longjmp() allowing to initialize a > jump buffer with a function pointer and a stack pointer. This will be > useful to later introduce threads. With this new function it becomes > possible to longjmp() to a particular function pointer (rather than > to a point previously reached during program execution as is the case > with setjmp()), and with a custom stack. Both things are needed to > spin off a new thread. Then the usual setjmp()/ longjmp() pair is > enough to save and restore a context, i.e., switch thread. > > Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org> > --- > arch/Kconfig | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/Kconfig b/arch/Kconfig > index 35b19f9bfdc..8d5b54031b3 100644 > --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -13,6 +13,12 @@ config HAVE_SETJMP > help > The architecture supports setjmp() and longjmp(). > > +config HAVE_INITJMP > + bool > + help > + The architecture supports initjmp(), a non-standard companion to > + setjmp() and longjmp(). > + > config SUPPORT_BIG_ENDIAN > bool > > -- > 2.43.0 >\ Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
On 25.02.25 17:34, Jerome Forissier wrote: > HAVE_INIJMP will be set by architectures that support initjmp(), a > non-standard extension to setjmp()/longjmp() allowing to initialize a > jump buffer with a function pointer and a stack pointer. This will be > useful to later introduce threads. With this new function it becomes > possible to longjmp() to a particular function pointer (rather than > to a point previously reached during program execution as is the case > with setjmp()), and with a custom stack. Both things are needed to > spin off a new thread. Then the usual setjmp()/ longjmp() pair is > enough to save and restore a context, i.e., switch thread. > > Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org> > --- > arch/Kconfig | 6 ++++++ > 1 file changed, 6 insertions(+) > > diff --git a/arch/Kconfig b/arch/Kconfig > index 35b19f9bfdc..8d5b54031b3 100644 > --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -13,6 +13,12 @@ config HAVE_SETJMP > help > The architecture supports setjmp() and longjmp(). > > +config HAVE_INITJMP > + bool HAVE_SETJMP controls if /arch/<arch>/lib/setjmp.S is compiled. Please, add the missing dependency. depends HAVE_SETJMP Best regards Heinrich > + help > + The architecture supports initjmp(), a non-standard companion to > + setjmp() and longjmp(). > + > config SUPPORT_BIG_ENDIAN > bool >
On 2/28/25 13:38, Heinrich Schuchardt wrote: > On 25.02.25 17:34, Jerome Forissier wrote: >> HAVE_INIJMP will be set by architectures that support initjmp(), a >> non-standard extension to setjmp()/longjmp() allowing to initialize a >> jump buffer with a function pointer and a stack pointer. This will be >> useful to later introduce threads. With this new function it becomes >> possible to longjmp() to a particular function pointer (rather than >> to a point previously reached during program execution as is the case >> with setjmp()), and with a custom stack. Both things are needed to >> spin off a new thread. Then the usual setjmp()/ longjmp() pair is >> enough to save and restore a context, i.e., switch thread. >> >> Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org> >> --- >> arch/Kconfig | 6 ++++++ >> 1 file changed, 6 insertions(+) >> >> diff --git a/arch/Kconfig b/arch/Kconfig >> index 35b19f9bfdc..8d5b54031b3 100644 >> --- a/arch/Kconfig >> +++ b/arch/Kconfig >> @@ -13,6 +13,12 @@ config HAVE_SETJMP >> help >> The architecture supports setjmp() and longjmp(). >> >> +config HAVE_INITJMP >> + bool > > HAVE_SETJMP controls if /arch/<arch>/lib/setjmp.S is compiled. > > Please, add the missing dependency. > > depends HAVE_SETJMP Ack. Thanks,
diff --git a/arch/Kconfig b/arch/Kconfig index 35b19f9bfdc..8d5b54031b3 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -13,6 +13,12 @@ config HAVE_SETJMP help The architecture supports setjmp() and longjmp(). +config HAVE_INITJMP + bool + help + The architecture supports initjmp(), a non-standard companion to + setjmp() and longjmp(). + config SUPPORT_BIG_ENDIAN bool
HAVE_INIJMP will be set by architectures that support initjmp(), a non-standard extension to setjmp()/longjmp() allowing to initialize a jump buffer with a function pointer and a stack pointer. This will be useful to later introduce threads. With this new function it becomes possible to longjmp() to a particular function pointer (rather than to a point previously reached during program execution as is the case with setjmp()), and with a custom stack. Both things are needed to spin off a new thread. Then the usual setjmp()/ longjmp() pair is enough to save and restore a context, i.e., switch thread. Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org> --- arch/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+)