| Message ID | 1411523383-9820-1-git-send-email-yocto6@gmail.com (mailing list archive) |
|---|---|
| State | Rejected |
| Headers | show |
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 <yocto6@gmail.com> > --- > 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 majordomo@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-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 <yocto6@gmail.com> >> --- >> 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 majordomo@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-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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 <yocto6@gmail.com> >>> --- >>> 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 majordomo@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.anglin@bell.net -- To unsubscribe from this list: send the line "unsubscribe linux-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Wed, Sep 24, 2014 at 8:42 AM, John David Anglin <dave.anglin@bell.net> 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 <yocto6@gmail.com> >>>> --- >>>> 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 majordomo@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.anglin@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-parisc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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;
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. Signed-off-by: Nicholas Krause <yocto6@gmail.com> --- arch/parisc/mm/init.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)