diff options
| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2012-10-05 16:52:18 +0200 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2012-10-09 14:17:01 +0200 |
| commit | c972cc60c23f5a6309292bfcc91a441743ba027e (patch) | |
| tree | 04f8fc1d4e78979d28a897a90bba5c3321555967 /arch/s390/kernel/setup.c | |
| parent | 021d48be48481821f6e3f53028915c0571874135 (diff) | |
s390/vmalloc: have separate modules area
Add a special module area on top of the vmalloc area, which may be only
used for modules and bpf jit generated code.
This makes sure that inter module branches will always happen without a
trampoline and in addition having all the code within a 2GB frame is
branch prediction unit friendly.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/kernel/setup.c')
| -rw-r--r-- | arch/s390/kernel/setup.c | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c index bfb48f18169..b1f2be9aaaa 100644 --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -105,6 +105,11 @@ EXPORT_SYMBOL(VMALLOC_END); struct page *vmemmap; EXPORT_SYMBOL(vmemmap); +#ifdef CONFIG_64BIT +unsigned long MODULES_VADDR; +unsigned long MODULES_END; +#endif + /* An array with a pointer to the lowcore of every CPU. */ struct _lowcore *lowcore_ptr[NR_CPUS]; EXPORT_SYMBOL(lowcore_ptr); @@ -544,19 +549,23 @@ static void __init setup_memory_end(void) /* Choose kernel address space layout: 2, 3, or 4 levels. */ #ifdef CONFIG_64BIT - vmalloc_size = VMALLOC_END ?: 128UL << 30; + vmalloc_size = VMALLOC_END ?: (128UL << 30) - MODULES_LEN; tmp = (memory_end ?: real_memory_size) / PAGE_SIZE; tmp = tmp * (sizeof(struct page) + PAGE_SIZE) + vmalloc_size; if (tmp <= (1UL << 42)) vmax = 1UL << 42; /* 3-level kernel page table */ else vmax = 1UL << 53; /* 4-level kernel page table */ + /* module area is at the end of the kernel address space. */ + MODULES_END = vmax; + MODULES_VADDR = MODULES_END - MODULES_LEN; + VMALLOC_END = MODULES_VADDR; #else vmalloc_size = VMALLOC_END ?: 96UL << 20; vmax = 1UL << 31; /* 2-level kernel page table */ -#endif /* vmalloc area is at the end of the kernel address space. */ VMALLOC_END = vmax; +#endif VMALLOC_START = vmax - vmalloc_size; /* Split remaining virtual space between 1:1 mapping & vmemmap array */ |