Re: [PATCH] Remove HAVE_VIRT_CPU_ACCOUNTING_GEN option

["Nicholas Piggin" <npiggin@xxxxxxxxx>]

On Sun Apr 30, 2023 at 6:14 AM AEST, Palmer Dabbelt wrote:
> On Fri, 28 Apr 2023 23:33:48 PDT (-0700), npiggin@xxxxxxxxx wrote:
> > This option was created in commit 554b0004d0ec4 ("vtime: Add
> > HAVE_VIRT_CPU_ACCOUNTING_GEN Kconfig") for architectures to indicate
> > they support the 64-bit cputime_t required for VIRT_CPU_ACCOUNTING_GEN.
> >
> > The cputime_t type has since been removed, so this doesn't have any
> > meaning. Remove it.
> >
> > Cc: linux-arch@xxxxxxxxxxxxxxx
> > Cc: linux-kernel@xxxxxxxxxxxxxxx
> > Cc: Vineet Gupta <vgupta@xxxxxxxxxx>
> > Cc: linux-snps-arc@xxxxxxxxxxxxxxxxxxx
> > Cc: Brian Cain <bcain@xxxxxxxxxxx>
> > Cc: linux-hexagon@xxxxxxxxxxxxxxx
> > Cc: Huacai Chen <chenhuacai@xxxxxxxxxx>
> > Cc: loongarch@xxxxxxxxxxxxxxx
> > Cc: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> > Cc: linux-m68k@xxxxxxxxxxxxxxxxxxxx
> > Cc: Michal Simek <monstr@xxxxxxxxx>
> > Cc: Thomas Bogendoerfer <tsbogend@xxxxxxxxxxxxxxxx>
> > Cc: linux-mips@xxxxxxxxxxxxxxx
> > Cc: Dinh Nguyen <dinguyen@xxxxxxxxxx>
> > Cc: Jonas Bonn <jonas@xxxxxxxxxxxx>
> > Cc: Stefan Kristiansson <stefan.kristiansson@xxxxxxxxxxxxx>
> > Cc: Stafford Horne <shorne@xxxxxxxxx>
> > Cc: linux-openrisc@xxxxxxxxxxxxxxx
> > Cc: "James E.J. Bottomley" <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx>
> > Cc: Helge Deller <deller@xxxxxx>
> > Cc: linux-parisc@xxxxxxxxxxxxxxx
> > Cc: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
> > Cc: Palmer Dabbelt <palmer@xxxxxxxxxxx>
> > Cc: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
> > Cc: linux-riscv@xxxxxxxxxxxxxxxxxxx
> > Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx>
> > Cc: Rich Felker <dalias@xxxxxxxx>
> > Cc: John Paul Adrian Glaubitz <glaubitz@xxxxxxxxxxxxxxxxxxx>
> > Cc: linux-sh@xxxxxxxxxxxxxxx
> > Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
> > Cc: sparclinux@xxxxxxxxxxxxxxx
> > Cc: Richard Weinberger <richard@xxxxxx>
> > Cc: Anton Ivanov <anton.ivanov@xxxxxxxxxxxxxxxxxx>
> > Cc: Johannes Berg <johannes@xxxxxxxxxxxxxxxx>
> > Cc: linux-um@xxxxxxxxxxxxxxxxxxx
> > Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
> > Cc: Ingo Molnar <mingo@xxxxxxxxxx>
> > Cc: Borislav Petkov <bp@xxxxxxxxx>
> > Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> > Cc: x86@xxxxxxxxxx
> > Cc: "H. Peter Anvin" <hpa@xxxxxxxxx>
> > Cc: Kevin Hilman <khilman@xxxxxxxxxxxx>
> > Cc: Frederic Weisbecker <frederic@xxxxxxxxxx>
> > Signed-off-by: Nicholas Piggin <npiggin@xxxxxxxxx>
> > ---
> > Hi,
> >
> > Could we tidy this? I don't know what tree it can go in, timers,
> > sched, asm-generic, probably doesn't matter.
> >
> > The only thing this actually does is gate VIRT_CPU_ACCOUNTING_GEN and
> > NO_HZ_FULL so if your arch has some other issue that requires this
> > then the documentation needs to change. Any concerns from the archs?
> > I.e., 32-bit that does *not* define HAVE_VIRT_CPU_ACCOUNTING_GEN
> > which looks to be:
> >
> > arc
> > hexagon
> > loongarch 32-bit with SMP
> > m68k
> > microblaze
> > mips 32-bit with SMP
> > nios2
> > openrisc
> > parisc 32-bit
> > riscv 32-bit
>
> Nothing's jumping out, though I haven't tested this yet so I'm not 100%.  
> I assume this isn't aimed for this merge window, given the timing?  

No, maybe the next one though.

> Probably best to give this sort of thing time to bake in linux-next, but 
> I doubt anyone is even paying attention to rv32/NO_HZ_FULL so no big 
> deal either way on my end.
>
> Acked-by: Palmer Dabbelt <palmer@xxxxxxxxxxxx> # RISC-V

Thanks,
Nick