From 85a6623152988c267cea008d20616b61ea9c223c Mon Sep 17 00:00:00 2001 From: Sverker Eriksson Date: Tue, 12 Apr 2016 20:41:58 +0200 Subject: erts: Add 'exec_alloc' for hipe code that uses its own super carrier (erts_exec_mmapper) to guarantee low addressed and executable memory (PROT_EXEC). Currently only used on x86_64 that needs low memory for HiPE/AMD64's small code model. By initializing erts_exec_mapper early we secure its low memory area before erts_literal_mmapper might steal it. --- erts/emulator/sys/common/erl_mmap.c | 45 ++++++++++++++++++++++++++++++++----- erts/emulator/sys/common/erl_mmap.h | 16 +++++++++++-- erts/emulator/sys/common/erl_mseg.c | 7 ++++++ erts/emulator/sys/common/erl_mseg.h | 4 +++- 4 files changed, 64 insertions(+), 8 deletions(-) (limited to 'erts/emulator/sys') diff --git a/erts/emulator/sys/common/erl_mmap.c b/erts/emulator/sys/common/erl_mmap.c index f5f40b35a8..38970bd24e 100644 --- a/erts/emulator/sys/common/erl_mmap.c +++ b/erts/emulator/sys/common/erl_mmap.c @@ -356,6 +356,12 @@ char* erts_literals_start; UWord erts_literals_size; #endif +#ifdef ERTS_ALC_A_EXEC +ErtsMemMapper erts_exec_mmapper; +#endif + + + #define ERTS_MMAP_SIZE_SC_SA_INC(SZ) \ do { \ mm->size.supercarrier.used.total += (SZ); \ @@ -1351,10 +1357,39 @@ os_unreserve_physical(char *ptr, UWord size) } static void * -os_mmap_virtual(char *ptr, UWord size) +os_mmap_virtual(char *ptr, UWord size, int exec) { - void *res = mmap((void *) ptr, (size_t) size, ERTS_MMAP_VIRTUAL_PROT, - ERTS_MMAP_VIRTUAL_FLAGS, ERTS_MMAP_FD, 0); + int flags = ERTS_MMAP_VIRTUAL_FLAGS; + void* res; + +#ifdef ERTS_ALC_A_EXEC + if (exec) { + ASSERT(!ptr); + /* OTP-19.0: Nice hack below cut-and-pasted from hipe_amd64.c */ + +# ifdef MAP_32BIT + /* If we got MAP_32BIT (Linux), then use that to ask for low memory */ + flags |= MAP_32BIT; +# else + /* FreeBSD doesn't have MAP_32BIT, and it doesn't respect + a plain map_hint (returns high mappings even though the + hint refers to a free area), so we have to use both map_hint + and MAP_FIXED to get addresses below the 2GB boundary. + This is even worse than the Linux/ppc64 case. + Similarly, Solaris 10 doesn't have MAP_32BIT, + and it doesn't respect a plain map_hint. */ + ptr = (char*)(512*1024*1024); /* 0.5GB */ + +# if defined(__FreeBSD__) || defined(__sun__) + flags |= MAP_FIXED; +# endif +# endif /* !MAP_32BIT */ + } +#else /* !ERTS_ALC_A_EXEC */ + ASSERT(!exec); +#endif + res = mmap((void *) ptr, (size_t) size, ERTS_MMAP_VIRTUAL_PROT, + flags, ERTS_MMAP_FD, 0); if (res == (void *) MAP_FAILED) return NULL; return res; @@ -2177,7 +2212,7 @@ erts_mmap_init(ErtsMemMapper* mm, ErtsMMapInit *init, int executable) ptr = (char *) ERTS_PAGEALIGNED_CEILING(init->virtual_range.start); end = (char *) ERTS_PAGEALIGNED_FLOOR(init->virtual_range.end); sz = end - ptr; - start = os_mmap_virtual(ptr, sz); + start = os_mmap_virtual(ptr, sz, executable); if (!start || start > ptr || start >= end) erts_exit(1, "erts_mmap: Failed to create virtual range for super carrier\n"); @@ -2202,7 +2237,7 @@ erts_mmap_init(ErtsMemMapper* mm, ErtsMMapInit *init, int executable) sz = ERTS_PAGEALIGNED_CEILING(init->scs); #ifdef ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION if (!init->scrpm) { - start = os_mmap_virtual(NULL, sz); + start = os_mmap_virtual(NULL, sz, executable); mm->reserve_physical = os_reserve_physical; mm->unreserve_physical = os_unreserve_physical; virtual_map = 1; diff --git a/erts/emulator/sys/common/erl_mmap.h b/erts/emulator/sys/common/erl_mmap.h index 30548bd0b0..8a7530d943 100644 --- a/erts/emulator/sys/common/erl_mmap.h +++ b/erts/emulator/sys/common/erl_mmap.h @@ -55,6 +55,11 @@ typedef struct { #define ERTS_MMAP_INIT_LITERAL_INITER \ {{NULL, NULL}, {NULL, NULL}, ERTS_LITERAL_VIRTUAL_AREA_SIZE, 1, (1 << 10), 0} +#define ERTS_HIPE_EXEC_VIRTUAL_AREA_SIZE (UWORD_CONSTANT(512)*1024*1024) + +#define ERTS_MMAP_INIT_HIPE_EXEC_INITER \ + {{NULL, NULL}, {NULL, NULL}, ERTS_HIPE_EXEC_VIRTUAL_AREA_SIZE, 1, (1 << 10), 0} + typedef struct ErtsMemMapper_ ErtsMemMapper; void *erts_mmap(ErtsMemMapper*, Uint32 flags, UWord *sizep); @@ -126,10 +131,17 @@ Eterm erts_mmap_debug_info(ErtsMemMapper*, struct process*); # define ERTS_HAVE_OS_MMAP 1 #endif +#ifdef ERTS_WANT_MEM_MAPPERS +# include "erl_alloc_types.h" + extern ErtsMemMapper erts_dflt_mmapper; -#if defined(ARCH_64) && defined(ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION) +# if defined(ARCH_64) && defined(ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION) extern ErtsMemMapper erts_literal_mmapper; -#endif +# endif +# ifdef ERTS_ALC_A_EXEC +extern ErtsMemMapper erts_exec_mmapper; +# endif +#endif /* ERTS_WANT_MEM_MAPPERS */ /*#define HARD_DEBUG_MSEG*/ #ifdef HARD_DEBUG_MSEG diff --git a/erts/emulator/sys/common/erl_mseg.c b/erts/emulator/sys/common/erl_mseg.c index f0fbb682b0..f373302e65 100644 --- a/erts/emulator/sys/common/erl_mseg.c +++ b/erts/emulator/sys/common/erl_mseg.c @@ -31,6 +31,7 @@ # include "config.h" #endif +#define ERTS_WANT_MEM_MAPPERS #include "sys.h" #include "erl_mseg.h" #include "global.h" @@ -1402,6 +1403,12 @@ erts_mseg_init(ErtsMsegInit_t *init) erts_mtx_init(&init_atoms_mutex, "mseg_init_atoms"); +#ifdef ERTS_ALC_A_EXEC + /* Initialize erts_exec_mapper *FIRST*, to increase probability + * of getting low memory for HiPE AMD64's small code model. + */ + erts_mmap_init(&erts_exec_mmapper, &init->exec_mmap, 1); +#endif erts_mmap_init(&erts_dflt_mmapper, &init->dflt_mmap, 0); #if defined(ARCH_64) && defined(ERTS_HAVE_OS_PHYSICAL_MEMORY_RESERVATION) erts_mmap_init(&erts_literal_mmapper, &init->literal_mmap, 0); diff --git a/erts/emulator/sys/common/erl_mseg.h b/erts/emulator/sys/common/erl_mseg.h index 2acd8f8505..556a135798 100644 --- a/erts/emulator/sys/common/erl_mseg.h +++ b/erts/emulator/sys/common/erl_mseg.h @@ -61,6 +61,7 @@ typedef struct { Uint nos; ErtsMMapInit dflt_mmap; ErtsMMapInit literal_mmap; + ErtsMMapInit exec_mmap; } ErtsMsegInit_t; #define ERTS_MSEG_INIT_DEFAULT_INITIALIZER \ @@ -70,7 +71,8 @@ typedef struct { 10, /* mcs: Max cache size */ \ 1000, /* cci: Cache check interval */ \ ERTS_MMAP_INIT_DEFAULT_INITER, \ - ERTS_MMAP_INIT_LITERAL_INITER \ + ERTS_MMAP_INIT_LITERAL_INITER, \ + ERTS_MMAP_INIT_HIPE_EXEC_INITER \ } typedef struct { -- cgit v1.2.3