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authorSverker Eriksson <[email protected]>2016-10-05 19:09:28 +0200
committerSverker Eriksson <[email protected]>2016-10-14 14:29:18 +0200
commit25b28611ea06d3e2d3708d20e53118ec24ae8321 (patch)
treea59b38eafae5acd8cb50257dec9161c88945130d
parente048ebf4bddf8434d0f4402863c0f6313a741df0 (diff)
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erts: Fix old leak for arm hipe code
* Use erts_alloc(ERTS_ALC_T_HIPE_EXEC,_) * Each module has its own trampolines * Stubs do not use trampolines, they do their own long jumps.
-rw-r--r--erts/emulator/hipe/hipe_arm.c201
-rw-r--r--erts/emulator/hipe/hipe_bif0.c1
2 files changed, 57 insertions, 145 deletions
diff --git a/erts/emulator/hipe/hipe_arm.c b/erts/emulator/hipe/hipe_arm.c
index 64e35b62d8..b61939724c 100644
--- a/erts/emulator/hipe/hipe_arm.c
+++ b/erts/emulator/hipe/hipe_arm.c
@@ -25,7 +25,6 @@
#endif
#include "global.h"
#include "erl_binary.h"
-#include <sys/mman.h>
#include "hipe_arch.h"
#include "hipe_native_bif.h" /* nbif_callemu() */
@@ -57,30 +56,6 @@ void hipe_flush_icache_word(void *address)
hipe_flush_icache_range(address, 4);
}
-/*
- * Management of 32MB code segments for regular code and trampolines.
- */
-
-#define SEGMENT_NRBYTES (32*1024*1024) /* named constant, _not_ a tunable */
-
-static struct segment {
- unsigned int *base; /* [base,base+32MB[ */
- unsigned int *code_pos; /* INV: base <= code_pos <= tramp_pos */
- unsigned int *tramp_pos; /* INV: tramp_pos <= base+32MB */
- /* On ARM we always allocate a trampoline at base+32MB-8 for
- nbif_callemu, so tramp_pos <= base+32MB-8. */
-} curseg;
-
-#define in_area(ptr,start,nbytes) \
- ((UWord)((char*)(ptr) - (char*)(start)) < (nbytes))
-
-static void *new_code_mapping(void)
-{
- return mmap(0, SEGMENT_NRBYTES,
- PROT_EXEC|PROT_READ|PROT_WRITE,
- MAP_PRIVATE|MAP_ANONYMOUS,
- -1, 0);
-}
static int check_callees(Eterm callees)
{
@@ -107,136 +82,53 @@ static int check_callees(Eterm callees)
return arity;
}
-static unsigned int *try_alloc(Uint nrwords, int nrcallees, Eterm callees, unsigned int **trampvec)
-{
- unsigned int *base, *address, *tramp_pos, nrfreewords;
- int trampnr;
- Eterm mfa, m, f;
- unsigned int a, *trampoline;
+#define TRAMPOLINE_WORDS 2
- m = NIL; f = NIL; a = 0; /* silence stupid compiler warning */
- tramp_pos = curseg.tramp_pos;
- address = curseg.code_pos;
- nrfreewords = tramp_pos - address;
- if (nrwords > nrfreewords)
- return NULL;
- curseg.code_pos = address + nrwords;
- nrfreewords -= nrwords;
-
- base = curseg.base;
- for (trampnr = 1; trampnr <= nrcallees; ++trampnr) {
- mfa = tuple_val(callees)[trampnr];
- if (is_atom(mfa))
- trampoline = hipe_primop_get_trampoline(mfa);
- else {
- m = tuple_val(mfa)[1];
- f = tuple_val(mfa)[2];
- a = unsigned_val(tuple_val(mfa)[3]);
- trampoline = hipe_mfa_get_trampoline(m, f, a);
- }
- if (!in_area(trampoline, base, SEGMENT_NRBYTES)) {
- if (nrfreewords < 2)
- return NULL;
- nrfreewords -= 2;
- tramp_pos = trampoline = tramp_pos - 2;
- trampoline[0] = 0xE51FF004; /* ldr pc, [pc,#-4] */
- trampoline[1] = 0; /* callee's address */
- hipe_flush_icache_range(trampoline, 2*sizeof(int));
- if (is_atom(mfa))
- hipe_primop_set_trampoline(mfa, trampoline);
- else
- hipe_mfa_set_trampoline(m, f, a, trampoline);
- }
- trampvec[trampnr-1] = trampoline;
+static void generate_trampolines(Uint32* address,
+ int nrcallees, Eterm callees,
+ Uint32** trampvec)
+{
+ Uint32* trampoline = address;
+ int i;
+
+ for (i = 0; i < nrcallees; ++i) {
+ trampoline[0] = 0xE51FF004; /* ldr pc, [pc,#-4] */
+ trampoline[1] = 0; /* callee's address */
+ trampvec[i] = trampoline;
+ trampoline += TRAMPOLINE_WORDS;
}
- curseg.tramp_pos = tramp_pos;
- return address;
+ hipe_flush_icache_range(address, nrcallees*2*sizeof(Uint32));
}
void *hipe_alloc_code(Uint nrbytes, Eterm callees, Eterm *trampolines, Process *p)
{
- Uint nrwords;
+ Uint code_words;
int nrcallees;
Eterm trampvecbin;
- unsigned int **trampvec;
- unsigned int *address;
- unsigned int *base;
- struct segment oldseg;
+ Uint32 **trampvec;
+ Uint32 *address;
if (nrbytes & 0x3)
return NULL;
- nrwords = nrbytes >> 2;
+ code_words = nrbytes / sizeof(Uint32);
nrcallees = check_callees(callees);
if (nrcallees < 0)
return NULL;
- trampvecbin = new_binary(p, NULL, nrcallees*sizeof(unsigned int*));
- trampvec = (unsigned int**)binary_bytes(trampvecbin);
+ trampvecbin = new_binary(p, NULL, nrcallees*sizeof(Uint32*));
+ trampvec = (Uint32**)binary_bytes(trampvecbin);
- address = try_alloc(nrwords, nrcallees, callees, trampvec);
- if (!address) {
- base = new_code_mapping();
- if (base == MAP_FAILED)
- return NULL;
- oldseg = curseg;
- curseg.base = base;
- curseg.code_pos = base;
- curseg.tramp_pos = (unsigned int*)((char*)base + SEGMENT_NRBYTES);
- curseg.tramp_pos -= 2;
- curseg.tramp_pos[0] = 0xE51FF004; /* ldr pc, [pc,#-4] */
- curseg.tramp_pos[1] = (unsigned int)&nbif_callemu;
+ address = erts_alloc(ERTS_ALC_T_HIPE_EXEC,
+ (code_words + nrcallees*TRAMPOLINE_WORDS)*sizeof(Uint32));
- address = try_alloc(nrwords, nrcallees, callees, trampvec);
- if (!address) {
- munmap(base, SEGMENT_NRBYTES);
- curseg = oldseg;
- return NULL;
- }
- /* commit to new segment, ignore leftover space in old segment */
- }
+ generate_trampolines(address + code_words, nrcallees, callees, trampvec);
*trampolines = trampvecbin;
return address;
}
void hipe_free_code(void* code, unsigned int bytes)
{
- /*SVERK: Leaking code memory */
-}
-
-static unsigned int *alloc_stub(Uint nrwords, unsigned int **tramp_callemu)
-{
- unsigned int *address;
- unsigned int *base;
- struct segment oldseg;
-
- address = try_alloc(nrwords, 0, NIL, NULL);
- if (!address) {
- base = new_code_mapping();
- if (base == MAP_FAILED)
- return NULL;
- oldseg = curseg;
- curseg.base = base;
- curseg.code_pos = base;
- curseg.tramp_pos = (unsigned int*)((char*)base + SEGMENT_NRBYTES);
- curseg.tramp_pos -= 2;
- curseg.tramp_pos[0] = 0xE51FF004; /* ldr pc, [pc,#-4] */
- curseg.tramp_pos[1] = (unsigned int)&nbif_callemu;
-
- address = try_alloc(nrwords, 0, NIL, NULL);
- if (!address) {
- munmap(base, SEGMENT_NRBYTES);
- curseg = oldseg;
- return NULL;
- }
- /* commit to new segment, ignore leftover space in old segment */
- }
- *tramp_callemu = (unsigned int*)((char*)curseg.base + SEGMENT_NRBYTES) - 2;
- return address;
-}
-
-void hipe_free_native_stub(void* stub)
-{
- /*SVERK: Leaking code stub */
+ erts_free(ERTS_ALC_T_HIPE_EXEC, code);
}
/*
@@ -276,8 +168,8 @@ int hipe_patch_insn(void *address, Uint32 value, Eterm type)
void *hipe_make_native_stub(void *callee_exp, unsigned int beamArity)
{
unsigned int *code;
- unsigned int *tramp_callemu;
int callemu_offset;
+ int is_short_jmp;
/*
* Native code calls BEAM via a stub looking as follows:
@@ -287,36 +179,57 @@ void *hipe_make_native_stub(void *callee_exp, unsigned int beamArity)
* b nbif_callemu
* .long callee_exp
*
+ * or if nbif_callemu is too far away:
+ *
+ * mov r0, #beamArity
+ * ldr r8, [pc,#0] // callee_exp
+ * ldr pc, [pc,#0] // nbif_callemu
+ * .long callee_exp
+ * .long nbif_callemu
+ *
* I'm using r0 and r8 since they aren't used for
- * parameter passing in native code. The branch to
- * nbif_callemu may need to go via a trampoline.
- * (Trampolines are allowed to modify r12, but they don't.)
+ * parameter passing in native code.
*/
- code = alloc_stub(4, &tramp_callemu);
+ code = erts_alloc(ERTS_ALC_T_HIPE_EXEC, 5*sizeof(Uint32));
if (!code)
return NULL;
callemu_offset = ((int)&nbif_callemu - ((int)&code[2] + 8)) >> 2;
- if (!(callemu_offset >= -0x00800000 && callemu_offset <= 0x007FFFFF)) {
- callemu_offset = ((int)tramp_callemu - ((int)&code[2] + 8)) >> 2;
- if (!(callemu_offset >= -0x00800000 && callemu_offset <= 0x007FFFFF))
- abort();
+ is_short_jmp = (callemu_offset >= -0x00800000 &&
+ callemu_offset <= 0x007FFFFF);
+#ifdef DEBUG
+ if (is_short_jmp && (callemu_offset % 3)==0) {
+ is_short_jmp = 0;
}
+#endif
/* mov r0, #beamArity */
code[0] = 0xE3A00000 | (beamArity & 0xFF);
/* ldr r8, [pc,#0] // callee_exp */
code[1] = 0xE59F8000;
- /* b nbif_callemu */
- code[2] = 0xEA000000 | (callemu_offset & 0x00FFFFFF);
+ if (is_short_jmp) {
+ /* b nbif_callemu */
+ code[2] = 0xEA000000 | (callemu_offset & 0x00FFFFFF);
+ }
+ else {
+ /* ldr pc, [pc,#0] // nbif_callemu */
+ code[2] = 0xE59FF000;
+ /* .long nbif_callemu */
+ code[4] = (unsigned int)&nbif_callemu;
+ }
/* .long callee_exp */
code[3] = (unsigned int)callee_exp;
- hipe_flush_icache_range(code, 4*sizeof(int));
+ hipe_flush_icache_range(code, 5*sizeof(Uint32));
return code;
}
+void hipe_free_native_stub(void* stub)
+{
+ erts_free(ERTS_ALC_T_HIPE_EXEC, stub);
+}
+
static void patch_b(Uint32 *address, Sint32 offset, Uint32 AA)
{
Uint32 oldI = *address;
diff --git a/erts/emulator/hipe/hipe_bif0.c b/erts/emulator/hipe/hipe_bif0.c
index 58eee1693f..f9a657124a 100644
--- a/erts/emulator/hipe/hipe_bif0.c
+++ b/erts/emulator/hipe/hipe_bif0.c
@@ -417,7 +417,6 @@ BIF_RETTYPE hipe_bifs_enter_code_3(BIF_ALIST_3)
ASSERT(bitoffs == 0);
ASSERT(bitsize == 0);
trampolines = NIL;
- // XXX: Trampolines are not tracked and freed
address = hipe_alloc_code(nrbytes, BIF_ARG_2, &trampolines, BIF_P);
if (!address) {
Uint nrcallees;