| Message ID | 20250214140031.484344-2-jerome.forissier@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | Uthreads | expand |
On 14.02.25 15:00, 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. How is initjmp() used in threading? A cover-letter for the series would have been helpful. > > 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(). If this required for thread support, I would have expected this to be in the help text. Best regards Heinrich > + > config SUPPORT_BIG_ENDIAN > bool >
Hi Heinrich, On 2/14/25 15:41, Heinrich Schuchardt wrote: > On 14.02.25 15:00, 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. > > How is initjmp() used in threading? It's used so that we can 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 thread. I will update the description. > > A cover-letter for the series would have been helpful. It's here [1]. [1] https://lists.denx.de/pipermail/u-boot/2025-February/580550.html > >> >> 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(). > > If this required for thread support, I would have expected this to be in > the help text. > > Best regards > > Heinrich > >> + >> config SUPPORT_BIG_ENDIAN >> bool >> >
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. Signed-off-by: Jerome Forissier <jerome.forissier@linaro.org> --- arch/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+)