Reduce 32GB RLIMIT_DATA on FreeBSD/x64 to allocate low-2GB memory.

Thanks to Tony Finch.
This commit is contained in:
Mike Pall 2010-10-23 16:31:27 +02:00
parent 02dc9d1082
commit 08b0ede194

View File

@ -171,12 +171,20 @@ static LJ_AINLINE int CALL_MUNMAP(void *ptr, size_t size)
/* Actually this only gives us max. 1GB in current Linux kernels. */ /* Actually this only gives us max. 1GB in current Linux kernels. */
#define CALL_MMAP(s) mmap(NULL, (s), MMAP_PROT, MAP_32BIT|MMAP_FLAGS, -1, 0) #define CALL_MMAP(s) mmap(NULL, (s), MMAP_PROT, MAP_32BIT|MMAP_FLAGS, -1, 0)
#elif defined(__MACH__) && defined(__APPLE__) #elif (defined(__MACH__) && defined(__APPLE__)) || \
defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
/* OSX mmap() uses a naive first-fit linear search. That's perfect for us. /* OSX and FreeBSD mmap() use a naive first-fit linear search.
** But -pagezero_size must be set, otherwise the lower 4GB are blocked. ** That's perfect for us. Except that -pagezero_size must be set for OSX,
** otherwise the lower 4GB are blocked. And the 32GB RLIMIT_DATA needs
** to be reduced to 250MB on FreeBSD.
*/ */
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
#include <sys/resource.h>
#define MMAP_REGION_START ((uintptr_t)0x10000000)
#else
#define MMAP_REGION_START ((uintptr_t)0x10000) #define MMAP_REGION_START ((uintptr_t)0x10000)
#endif
#define MMAP_REGION_END ((uintptr_t)0x80000000) #define MMAP_REGION_END ((uintptr_t)0x80000000)
static LJ_AINLINE void *CALL_MMAP(size_t size) static LJ_AINLINE void *CALL_MMAP(size_t size)
@ -184,6 +192,15 @@ static LJ_AINLINE void *CALL_MMAP(size_t size)
/* Hint for next allocation. Doesn't need to be thread-safe. */ /* Hint for next allocation. Doesn't need to be thread-safe. */
static uintptr_t alloc_hint = MMAP_REGION_START; static uintptr_t alloc_hint = MMAP_REGION_START;
int retry = 0; int retry = 0;
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
static int rlimit_modified = 0;
if (LJ_UNLIKELY(rlimit_modified == 0)) {
struct rlimit rlim;
rlim.rlim_cur = rlim.rlim_max = MMAP_REGION_START;
setrlimit(RLIMIT_DATA, &rlim); /* Ignore result. May fail below. */
rlimit_modified = 1;
}
#endif
for (;;) { for (;;) {
void *p = mmap((void *)alloc_hint, size, MMAP_PROT, MMAP_FLAGS, -1, 0); void *p = mmap((void *)alloc_hint, size, MMAP_PROT, MMAP_FLAGS, -1, 0);
if ((uintptr_t)p >= MMAP_REGION_START && if ((uintptr_t)p >= MMAP_REGION_START &&
@ -199,12 +216,6 @@ static LJ_AINLINE void *CALL_MMAP(size_t size)
return CMFAIL; return CMFAIL;
} }
#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
/* FreeBSD 64 bit kernel ignores mmap() hints for lower 32GB of memory. */
/* See: grep -C15 RLIMIT_DATA /usr/src/sys/vm/vm_mmap.c */
#error "No support for 64 bit FreeBSD"
#else #else
#error "NYI: need an equivalent of MAP_32BIT for this 64 bit OS" #error "NYI: need an equivalent of MAP_32BIT for this 64 bit OS"