* [PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative [not found] <e2424619-2a5a-a44a-2dc0-a16310725250@gmail.com> @ 2020-12-14 11:43 ` Alejandro Colomar 2020-12-14 12:00 ` Heinrich Schuchardt 2020-12-15 13:30 ` [PATCH v6] " Alejandro Colomar 1 sibling, 1 reply; 5+ messages in thread From: Alejandro Colomar @ 2020-12-14 11:43 UTC (permalink / raw) To: Michael Kerrisk, Dave Martin, Heinrich Schuchardt, linux-man Cc: Alejandro Colomar, Vineet Gupta, linux-snps-arc, Guo Ren, linux-csky, Thomas Bogendoerfer, linux-mips, Nick Hu, Greentime Hu, Vincent Chen, gcc-patches, cfe-users, cfe-dev Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> --- man2/cacheflush.2 | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/man2/cacheflush.2 b/man2/cacheflush.2 index aba625721..7a2eed506 100644 --- a/man2/cacheflush.2 +++ b/man2/cacheflush.2 @@ -86,6 +86,30 @@ On Linux, this call first appeared on the MIPS architecture, but nowadays, Linux provides a .BR cacheflush () system call on some other architectures, but with different arguments. +.SH NOTES +Unless you need the finer grained control that this system call provides, +you probably want to use the GCC built-in function +.BR __builtin___clear_cache (), +which provides a portable interface +across platforms supported by GCC and compatible compilers: +.PP +.in +4n +.EX +.BI "void __builtin___clear_cache(void *" begin ", void *" end ); +.EE +.in +.PP +On platforms that don't require instruction cache flushes, +.BR __builtin___clear_cache () +has no effect. +.PP +.IR Note : +Until GCC 9.1.0, +the prototype for this built-in function used +.I char * +instead of +.I void * +for the parameters. .SH BUGS Linux kernels older than version 2.6.11 ignore the .I addr -- 2.29.2 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative 2020-12-14 11:43 ` [PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative Alejandro Colomar @ 2020-12-14 12:00 ` Heinrich Schuchardt 0 siblings, 0 replies; 5+ messages in thread From: Heinrich Schuchardt @ 2020-12-14 12:00 UTC (permalink / raw) To: Alejandro Colomar, Michael Kerrisk, Dave Martin, linux-man Cc: Vineet Gupta, linux-snps-arc, Guo Ren, linux-csky, Thomas Bogendoerfer, linux-mips, Nick Hu, Greentime Hu, Vincent Chen, gcc-patches, cfe-users, cfe-dev On 12/14/20 12:43 PM, Alejandro Colomar wrote: > Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> > Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de> > --- > man2/cacheflush.2 | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/man2/cacheflush.2 b/man2/cacheflush.2 > index aba625721..7a2eed506 100644 > --- a/man2/cacheflush.2 > +++ b/man2/cacheflush.2 > @@ -86,6 +86,30 @@ On Linux, this call first appeared on the MIPS architecture, > but nowadays, Linux provides a > .BR cacheflush () > system call on some other architectures, but with different arguments. > +.SH NOTES > +Unless you need the finer grained control that this system call provides, > +you probably want to use the GCC built-in function > +.BR __builtin___clear_cache (), > +which provides a portable interface > +across platforms supported by GCC and compatible compilers: > +.PP > +.in +4n > +.EX > +.BI "void __builtin___clear_cache(void *" begin ", void *" end ); > +.EE > +.in > +.PP > +On platforms that don't require instruction cache flushes, > +.BR __builtin___clear_cache () > +has no effect. > +.PP > +.IR Note : > +Until GCC 9.1.0, > +the prototype for this built-in function used > +.I char * > +instead of > +.I void * > +for the parameters. > .SH BUGS > Linux kernels older than version 2.6.11 ignore the > .I addr > ^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH v6] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative [not found] <e2424619-2a5a-a44a-2dc0-a16310725250@gmail.com> 2020-12-14 11:43 ` [PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative Alejandro Colomar @ 2020-12-15 13:30 ` Alejandro Colomar 2020-12-20 15:35 ` Ping: " Alejandro Colomar (man-pages) 2020-12-20 20:48 ` Michael Kerrisk (man-pages) 1 sibling, 2 replies; 5+ messages in thread From: Alejandro Colomar @ 2020-12-15 13:30 UTC (permalink / raw) To: Michael Kerrisk, Dave Martin, Heinrich Schuchardt, linux-man, Martin Sebor Cc: Alejandro Colomar, Vineet Gupta, linux-snps-arc, Guo Ren, linux-csky, Thomas Bogendoerfer, linux-mips, Nick Hu, Greentime Hu, Vincent Chen, gcc-patches, cfe-users, cfe-dev Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> Cc: Martin Sebor <msebor@redhat.com> Cc: Dave Martin <Dave.Martin@arm.com> --- v6: - GCC has always exposed 'void *', as Martin Sebor noted. It's Clang (and maybe others) that (following GCC's docs) exposed 'char *'. man2/cacheflush.2 | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+) diff --git a/man2/cacheflush.2 b/man2/cacheflush.2 index aba625721..7a2eed506 100644 --- a/man2/cacheflush.2 +++ b/man2/cacheflush.2 @@ -86,6 +86,30 @@ On Linux, this call first appeared on the MIPS architecture, but nowadays, Linux provides a .BR cacheflush () system call on some other architectures, but with different arguments. +.SH NOTES +Unless you need the finer grained control that this system call provides, +you probably want to use the GCC built-in function +.BR __builtin___clear_cache (), +which provides a portable interface +across platforms supported by GCC and compatible compilers: +.PP +.in +4n +.EX +.BI "void __builtin___clear_cache(void *" begin ", void *" end ); +.EE +.in +.PP +On platforms that don't require instruction cache flushes, +.BR __builtin___clear_cache () +has no effect. +.PP +.IR Note : +On some GCC-compatible compilers, +the prototype for this built-in function uses +.I char * +instead of +.I void * +for the parameters. .SH BUGS Linux kernels older than version 2.6.11 ignore the .I addr -- 2.29.2 ^ permalink raw reply related [flat|nested] 5+ messages in thread
* Ping: [PATCH v6] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative 2020-12-15 13:30 ` [PATCH v6] " Alejandro Colomar @ 2020-12-20 15:35 ` Alejandro Colomar (man-pages) 2020-12-20 20:48 ` Michael Kerrisk (man-pages) 1 sibling, 0 replies; 5+ messages in thread From: Alejandro Colomar (man-pages) @ 2020-12-20 15:35 UTC (permalink / raw) To: Michael Kerrisk, linux-man Cc: Vineet Gupta, Dave Martin, linux-snps-arc, Martin Sebor, Guo Ren, linux-csky, Thomas Bogendoerfer, Heinrich Schuchardt, linux-mips, Nick Hu, Greentime Hu, Vincent Chen, gcc-patches, cfe-users, cfe-dev Ping On 12/15/20 2:30 PM, Alejandro Colomar wrote: > Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> > Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> > Cc: Martin Sebor <msebor@redhat.com> > Cc: Dave Martin <Dave.Martin@arm.com> > --- > > v6: > - GCC has always exposed 'void *', as Martin Sebor noted. > It's Clang (and maybe others) that (following GCC's docs) > exposed 'char *'. > > man2/cacheflush.2 | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/man2/cacheflush.2 b/man2/cacheflush.2 > index aba625721..7a2eed506 100644 > --- a/man2/cacheflush.2 > +++ b/man2/cacheflush.2 > @@ -86,6 +86,30 @@ On Linux, this call first appeared on the MIPS architecture, > but nowadays, Linux provides a > .BR cacheflush () > system call on some other architectures, but with different arguments. > +.SH NOTES > +Unless you need the finer grained control that this system call provides, > +you probably want to use the GCC built-in function > +.BR __builtin___clear_cache (), > +which provides a portable interface > +across platforms supported by GCC and compatible compilers: > +.PP > +.in +4n > +.EX > +.BI "void __builtin___clear_cache(void *" begin ", void *" end ); > +.EE > +.in > +.PP > +On platforms that don't require instruction cache flushes, > +.BR __builtin___clear_cache () > +has no effect. > +.PP > +.IR Note : > +On some GCC-compatible compilers, > +the prototype for this built-in function uses > +.I char * > +instead of > +.I void * > +for the parameters. > .SH BUGS > Linux kernels older than version 2.6.11 ignore the > .I addr > -- Alejandro Colomar Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/ http://www.alejandro-colomar.es/ ^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH v6] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative 2020-12-15 13:30 ` [PATCH v6] " Alejandro Colomar 2020-12-20 15:35 ` Ping: " Alejandro Colomar (man-pages) @ 2020-12-20 20:48 ` Michael Kerrisk (man-pages) 1 sibling, 0 replies; 5+ messages in thread From: Michael Kerrisk (man-pages) @ 2020-12-20 20:48 UTC (permalink / raw) To: Alejandro Colomar, Dave Martin, Heinrich Schuchardt, linux-man, Martin Sebor Cc: mtk.manpages, Vineet Gupta, linux-snps-arc, Guo Ren, linux-csky, Thomas Bogendoerfer, linux-mips, Nick Hu, Greentime Hu, Vincent Chen, gcc-patches, cfe-users, cfe-dev On 12/15/20 2:30 PM, Alejandro Colomar wrote: > Reported-by: Heinrich Schuchardt <xypron.glpk@gmx.de> > Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com> > Cc: Martin Sebor <msebor@redhat.com> > Cc: Dave Martin <Dave.Martin@arm.com> > --- > > v6: > - GCC has always exposed 'void *', as Martin Sebor noted. > It's Clang (and maybe others) that (following GCC's docs) > exposed 'char *'. Thanks, Alex. Patch applied. Cheers, Michael > man2/cacheflush.2 | 24 ++++++++++++++++++++++++ > 1 file changed, 24 insertions(+) > > diff --git a/man2/cacheflush.2 b/man2/cacheflush.2 > index aba625721..7a2eed506 100644 > --- a/man2/cacheflush.2 > +++ b/man2/cacheflush.2 > @@ -86,6 +86,30 @@ On Linux, this call first appeared on the MIPS architecture, > but nowadays, Linux provides a > .BR cacheflush () > system call on some other architectures, but with different arguments. > +.SH NOTES > +Unless you need the finer grained control that this system call provides, > +you probably want to use the GCC built-in function > +.BR __builtin___clear_cache (), > +which provides a portable interface > +across platforms supported by GCC and compatible compilers: > +.PP > +.in +4n > +.EX > +.BI "void __builtin___clear_cache(void *" begin ", void *" end ); > +.EE > +.in > +.PP > +On platforms that don't require instruction cache flushes, > +.BR __builtin___clear_cache () > +has no effect. > +.PP > +.IR Note : > +On some GCC-compatible compilers, > +the prototype for this built-in function uses > +.I char * > +instead of > +.I void * > +for the parameters. > .SH BUGS > Linux kernels older than version 2.6.11 ignore the > .I addr > -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/ ^ permalink raw reply [flat|nested] 5+ messages in thread
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[not found] <e2424619-2a5a-a44a-2dc0-a16310725250@gmail.com>
2020-12-14 11:43 ` [PATCH v5] cacheflush.2: Document __builtin___clear_cache() as a more portable alternative Alejandro Colomar
2020-12-14 12:00 ` Heinrich Schuchardt
2020-12-15 13:30 ` [PATCH v6] " Alejandro Colomar
2020-12-20 15:35 ` Ping: " Alejandro Colomar (man-pages)
2020-12-20 20:48 ` Michael Kerrisk (man-pages)
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