RE: [PATCH 07/16] powerpc: mm: Support MAP_BELOW_HINT
David Laight <[email protected]>
| Newsgroups | gmane.linux.ports.mips,gmane.linux.kernel.cross-arch,gmane.linux.kernel,gmane.linux.ports.riscv,gmane.linux.ports.arm.kernel,gmane.linux.ports.ppc64.devel,gmane.linux.kernel.mm,gmane.linux.ports.parisc,gmane.linux.ports.sh.devel,gmane.linux.ports.sparc |
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| Message-ID | <[email protected]> |
From: Christophe Leroy > Sent: 28 August 2024 07:35 > Hi Charlie, > > Le 28/08/2024 à 07:49, Charlie Jenkins a écrit : > > Add support for MAP_BELOW_HINT to arch_get_mmap_base() and > > arch_get_mmap_end(). > > > > Signed-off-by: Charlie Jenkins <[email protected]> > > --- > > arch/powerpc/include/asm/task_size_64.h | 36 +++++++++++++++++++++++++++------ > > 1 file changed, 30 insertions(+), 6 deletions(-) > > > > diff --git a/arch/powerpc/include/asm/task_size_64.h b/arch/powerpc/include/asm/task_size_64.h > > index 239b363841aa..a37a5a81365d 100644 > > --- a/arch/powerpc/include/asm/task_size_64.h > > +++ b/arch/powerpc/include/asm/task_size_64.h > > @@ -72,12 +72,36 @@ > > #define STACK_TOP_MAX TASK_SIZE_USER64 > > #define STACK_TOP (is_32bit_task() ? STACK_TOP_USER32 : STACK_TOP_USER64) > > > > -#define arch_get_mmap_base(addr, len, base, flags) \ > > - (((addr) > DEFAULT_MAP_WINDOW) ? (base) + TASK_SIZE - DEFAULT_MAP_WINDOW : (base)) > > +#define arch_get_mmap_base(addr, len, base, flags) \ > > This macro looks quite big for a macro, can it be a static inline > function instead ? Same for the other macro below. Or even a real function? Given the actual cost of mapping memory an extra function call isn't going to be masurable. David > > > +({ \ > > + unsigned long mmap_base; \ > > + typeof(flags) _flags = (flags); \ > > + typeof(addr) _addr = (addr); \ > > + typeof(base) _base = (base); \ > > + typeof(len) _len = (len); \ > > + unsigned long rnd_gap = DEFAULT_MAP_WINDOW - (_base); \ > > + if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1)))\ > > + mmap_base = (_addr + _len) - rnd_gap; \ > > + else \ > > + mmap_end = ((_addr > DEFAULT_MAP_WINDOW) ? \ > > + _base + TASK_SIZE - DEFAULT_MAP_WINDOW : \ > > + _base); \ > > + mmap_end; \ > > mmap_end doesn't exist, did you mean mmap_base ? > > > +}) > > > > -#define arch_get_mmap_end(addr, len, flags) \ > > - (((addr) > DEFAULT_MAP_WINDOW) || \ > > - (((flags) & MAP_FIXED) && ((addr) + (len) > DEFAULT_MAP_WINDOW)) ? TASK_SIZE : \ > > - DEFAULT_MAP_WINDOW) > > +#define arch_get_mmap_end(addr, len, flags) \ > > +({ \ > > + unsigned long mmap_end; \ > > + typeof(flags) _flags = (flags); \ > > + typeof(addr) _addr = (addr); \ > > + typeof(len) _len = (len); \ > > + if (_flags & MAP_BELOW_HINT && _addr != 0 && ((_addr + _len) > BIT(VA_BITS - 1))) \ > > + mmap_end = (_addr + _len); \ > > + else \ > > + mmap_end = (((_addr) > DEFAULT_MAP_WINDOW) || \ > > + (((_flags) & MAP_FIXED) && ((_addr) + (_len) > DEFAULT_MAP_WINDOW))\ > > + ? TASK_SIZE : DEFAULT_MAP_WINDOW) \ > > + mmap_end; \ > > +}) > > > > #endif /* _ASM_POWERPC_TASK_SIZE_64_H */ > > - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)