| Message ID | 20240812115945.484051-4-ubizjak@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Enable strict percpu address space checks | expand |
On Mon, Aug 12, 2024 at 9:12 PM Nadav Amit <nadav.amit@gmail.com> wrote: > > > > > On 12 Aug 2024, at 14:57, Uros Bizjak <ubizjak@gmail.com> wrote: > > > > +#define per_cpu_qual /* nothing */ > > I wouldn't do that (the “/* nothing */“ part). It might cause a mess > unnecessarily is used with a comment. I took this /* nothing */ idea from the definition of BTF_TYPE_TAG in compiler_types.h. But yes, it doesn't bring anything here so let's remove it. Thanks, Uros.
diff --git a/include/asm-generic/percpu.h b/include/asm-generic/percpu.h index c091e09046c5..5f85d7ba8e2d 100644 --- a/include/asm-generic/percpu.h +++ b/include/asm-generic/percpu.h @@ -6,6 +6,21 @@ #include <linux/threads.h> #include <linux/percpu-defs.h> +/* + * per_cpu_qual is the qualifier for the percpu named address space. + * + * Most arches use generic named address space for percpu variables but + * some arches define percpu variables in different named address space + * (on the x86 arch, percpu variables may be declared as being relative + * to the %fs or %gs segments using __seg_fs or __seg_gs named address + * space qualifiers). + */ +#ifdef __per_cpu_qual +#define per_cpu_qual __per_cpu_qual +#else +#define per_cpu_qual /* nothing */ +#endif + #ifdef CONFIG_SMP /* diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index f14c275950b5..4c5917b97bc3 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -57,7 +57,7 @@ static inline void __chk_io_ptr(const volatile void __iomem *ptr) { } # define __user BTF_TYPE_TAG(user) # endif # define __iomem -# define __percpu BTF_TYPE_TAG(percpu) +# define __percpu per_cpu_qual BTF_TYPE_TAG(percpu) # define __rcu BTF_TYPE_TAG(rcu) # define __chk_user_ptr(x) (void)0
The patch introduces per_cpu_qual define and repurposes __percpu tag as a named address space qualifier using the new define. Arches can now conditionally define __per_cpu_qual as their named address space qualifier for percpu variables. Signed-off-by: Uros Bizjak <ubizjak@gmail.com> Cc: Dennis Zhou <dennis@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Christoph Lameter <cl@linux.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Luc Van Oostenryck <luc.vanoostenryck@gmail.com> --- include/asm-generic/percpu.h | 15 +++++++++++++++ include/linux/compiler_types.h | 2 +- 2 files changed, 16 insertions(+), 1 deletion(-)