Re: [PATCH] parisc:Remove unnecessary FIXMES in init.c
On Wed, Sep 24, 2014 at 8:42 AM, John David Anglin wrote: > On 24-Sep-14, at 7:42 AM, nick wrote: > >> >> >> On 14-09-24 01:30 AM, Guenter Roeck wrote: >>> >>> On Tue, Sep 23, 2014 at 09:49:43PM -0400, Nicholas Krause wrote: This removes the two fixmes in the file, init.c for compiler hints for comments related to compiler hints in linux_gateway_page_addr and map_hpux_gateway_page to change from FIXME to HINT in order for people reading this code to understand that these are compiler hints. >>> >>> "* const" tells the compiler that a pointer is a constant. >>> It doesn't tell the compiler that the data shall not be treated >>> as DP-relative. >>> >>> FIXME as in: We should find a better way to tell the compiler to >>> not treat this data as DP-relative. >>> >>> Can you please stop this ? >>> >>> Guenter >>> Signed-off-by: Nicholas Krause --- arch/parisc/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index 0bef864..668102e 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -733,7 +733,7 @@ static void __init pagetable_init(void) static void __init gateway_init(void) { unsigned long linux_gateway_page_addr; - /* FIXME: This is 'const' in order to trick the compiler + /* HINT: This is 'const' in order to trick the compiler into not treating it as DP-relative data. */ extern void * const linux_gateway_page; @@ -761,7 +761,7 @@ map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm) unsigned long start_pte; unsigned long address; unsigned long hpux_gw_page_addr; - /* FIXME: This is 'const' in order to trick the compiler + /* HINT: This is 'const' in order to trick the compiler into not treating it as DP-relative data. */ extern void * const hpux_gateway_page; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ >> Guenter, >> I asked the maintainers and I got, >> On 9/23/2014 4:48 PM, Helge Deller wrote: >>> >>> The FIXME: is misleading. It should maybe better read "HINT:" or >>> something like that. >>> Trivially it's basically just casting the symbol so that the compiler >>> will produce the correct code later on. >>> There is nothing you could try to "fix". >> >> Why not just remove "FIXME: " from these comments? > > > > The wording of the comment is not good. You can't "trick" the compiler into > not > treating a constant as DP-relative data. Whether or not a constant is > loaded as an > immediate depends on its value. > > Dave > -- > John David Anglin dave.ang...@bell.net > > > Are stating I need to change the wording of my commit or the comment? Nick -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] parisc:Remove unnecessary FIXMES in init.c
On 24-Sep-14, at 7:42 AM, nick wrote: On 14-09-24 01:30 AM, Guenter Roeck wrote: On Tue, Sep 23, 2014 at 09:49:43PM -0400, Nicholas Krause wrote: This removes the two fixmes in the file, init.c for compiler hints for comments related to compiler hints in linux_gateway_page_addr and map_hpux_gateway_page to change from FIXME to HINT in order for people reading this code to understand that these are compiler hints. "* const" tells the compiler that a pointer is a constant. It doesn't tell the compiler that the data shall not be treated as DP-relative. FIXME as in: We should find a better way to tell the compiler to not treat this data as DP-relative. Can you please stop this ? Guenter Signed-off-by: Nicholas Krause --- arch/parisc/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index 0bef864..668102e 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -733,7 +733,7 @@ static void __init pagetable_init(void) static void __init gateway_init(void) { unsigned long linux_gateway_page_addr; - /* FIXME: This is 'const' in order to trick the compiler + /* HINT: This is 'const' in order to trick the compiler into not treating it as DP-relative data. */ extern void * const linux_gateway_page; @@ -761,7 +761,7 @@ map_hpux_gateway_page(struct task_struct *tsk, struct mm_struct *mm) unsigned long start_pte; unsigned long address; unsigned long hpux_gw_page_addr; - /* FIXME: This is 'const' in order to trick the compiler + /* HINT: This is 'const' in order to trick the compiler into not treating it as DP-relative data. */ extern void * const hpux_gateway_page; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux- kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/ Guenter, I asked the maintainers and I got, On 9/23/2014 4:48 PM, Helge Deller wrote: The FIXME: is misleading. It should maybe better read "HINT:" or something like that. Trivially it's basically just casting the symbol so that the compiler will produce the correct code later on. There is nothing you could try to "fix". Why not just remove "FIXME: " from these comments? The wording of the comment is not good. You can't "trick" the compiler into not treating a constant as DP-relative data. Whether or not a constant is loaded as an immediate depends on its value. Dave -- John David Anglin dave.ang...@bell.net -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] parisc:Remove unnecessary FIXMES in init.c
On 14-09-24 01:30 AM, Guenter Roeck wrote: > On Tue, Sep 23, 2014 at 09:49:43PM -0400, Nicholas Krause wrote: >> This removes the two fixmes in the file, init.c for compiler hints >> for comments related to compiler hints in linux_gateway_page_addr >> and map_hpux_gateway_page to change from FIXME to HINT in order >> for people reading this code to understand that these are compiler >> hints. >> > > "* const" tells the compiler that a pointer is a constant. > It doesn't tell the compiler that the data shall not be treated > as DP-relative. > > FIXME as in: We should find a better way to tell the compiler to > not treat this data as DP-relative. > > Can you please stop this ? > > Guenter > >> Signed-off-by: Nicholas Krause >> --- >> arch/parisc/mm/init.c | 4 ++-- >> 1 file changed, 2 insertions(+), 2 deletions(-) >> >> diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c >> index 0bef864..668102e 100644 >> --- a/arch/parisc/mm/init.c >> +++ b/arch/parisc/mm/init.c >> @@ -733,7 +733,7 @@ static void __init pagetable_init(void) >> static void __init gateway_init(void) >> { >> unsigned long linux_gateway_page_addr; >> -/* FIXME: This is 'const' in order to trick the compiler >> +/* HINT: This is 'const' in order to trick the compiler >> into not treating it as DP-relative data. */ >> extern void * const linux_gateway_page; >> >> @@ -761,7 +761,7 @@ map_hpux_gateway_page(struct task_struct *tsk, struct >> mm_struct *mm) >> unsigned long start_pte; >> unsigned long address; >> unsigned long hpux_gw_page_addr; >> -/* FIXME: This is 'const' in order to trick the compiler >> +/* HINT: This is 'const' in order to trick the compiler >> into not treating it as DP-relative data. */ >> extern void * const hpux_gateway_page; >> >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in >> the body of a message to majord...@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html >> Please read the FAQ at http://www.tux.org/lkml/ >> >> Guenter, I asked the maintainers and I got, On 9/23/2014 4:48 PM, Helge Deller wrote: > The FIXME: is misleading. It should maybe better read "HINT:" or something > like that. > Trivially it's basically just casting the symbol so that the compiler > will produce the correct code later on. > There is nothing you could try to "fix". Why not just remove "FIXME: " from these comments? Dave As the reply. Cheers Nick -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH] parisc:Remove unnecessary FIXMES in init.c
On Tue, Sep 23, 2014 at 09:49:43PM -0400, Nicholas Krause wrote: > This removes the two fixmes in the file, init.c for compiler hints > for comments related to compiler hints in linux_gateway_page_addr > and map_hpux_gateway_page to change from FIXME to HINT in order > for people reading this code to understand that these are compiler > hints. > "* const" tells the compiler that a pointer is a constant. It doesn't tell the compiler that the data shall not be treated as DP-relative. FIXME as in: We should find a better way to tell the compiler to not treat this data as DP-relative. Can you please stop this ? Guenter > Signed-off-by: Nicholas Krause > --- > arch/parisc/mm/init.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c > index 0bef864..668102e 100644 > --- a/arch/parisc/mm/init.c > +++ b/arch/parisc/mm/init.c > @@ -733,7 +733,7 @@ static void __init pagetable_init(void) > static void __init gateway_init(void) > { > unsigned long linux_gateway_page_addr; > - /* FIXME: This is 'const' in order to trick the compiler > + /* HINT: This is 'const' in order to trick the compiler > into not treating it as DP-relative data. */ > extern void * const linux_gateway_page; > > @@ -761,7 +761,7 @@ map_hpux_gateway_page(struct task_struct *tsk, struct > mm_struct *mm) > unsigned long start_pte; > unsigned long address; > unsigned long hpux_gw_page_addr; > - /* FIXME: This is 'const' in order to trick the compiler > + /* HINT: This is 'const' in order to trick the compiler > into not treating it as DP-relative data. */ > extern void * const hpux_gateway_page; > > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majord...@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/