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-rw-r--r--util/coroutine-sigaltstack.c25
-rw-r--r--util/coroutine-ucontext.c11
-rw-r--r--util/coroutine-win32.c2
-rw-r--r--util/oslib-posix.c77
4 files changed, 97 insertions, 18 deletions
diff --git a/util/coroutine-sigaltstack.c b/util/coroutine-sigaltstack.c
index a7c3366553..f6fc49a0e5 100644
--- a/util/coroutine-sigaltstack.c
+++ b/util/coroutine-sigaltstack.c
@@ -33,8 +33,9 @@
typedef struct {
Coroutine base;
void *stack;
+ size_t stack_size;
sigjmp_buf env;
-} CoroutineUContext;
+} CoroutineSigAltStack;
/**
* Per-thread coroutine bookkeeping
@@ -44,7 +45,7 @@ typedef struct {
Coroutine *current;
/** The default coroutine */
- CoroutineUContext leader;
+ CoroutineSigAltStack leader;
/** Information for the signal handler (trampoline) */
sigjmp_buf tr_reenter;
@@ -89,7 +90,7 @@ static void __attribute__((constructor)) coroutine_init(void)
* (from the signal handler when it is not signal handling, read ahead
* for more information).
*/
-static void coroutine_bootstrap(CoroutineUContext *self, Coroutine *co)
+static void coroutine_bootstrap(CoroutineSigAltStack *self, Coroutine *co)
{
/* Initialize longjmp environment and switch back the caller */
if (!sigsetjmp(self->env, 0)) {
@@ -109,7 +110,7 @@ static void coroutine_bootstrap(CoroutineUContext *self, Coroutine *co)
*/
static void coroutine_trampoline(int signal)
{
- CoroutineUContext *self;
+ CoroutineSigAltStack *self;
Coroutine *co;
CoroutineThreadState *coTS;
@@ -143,8 +144,7 @@ static void coroutine_trampoline(int signal)
Coroutine *qemu_coroutine_new(void)
{
- const size_t stack_size = 1 << 20;
- CoroutineUContext *co;
+ CoroutineSigAltStack *co;
CoroutineThreadState *coTS;
struct sigaction sa;
struct sigaction osa;
@@ -164,7 +164,8 @@ Coroutine *qemu_coroutine_new(void)
*/
co = g_malloc0(sizeof(*co));
- co->stack = g_malloc(stack_size);
+ co->stack_size = COROUTINE_STACK_SIZE;
+ co->stack = qemu_alloc_stack(&co->stack_size);
co->base.entry_arg = &old_env; /* stash away our jmp_buf */
coTS = coroutine_get_thread_state();
@@ -189,7 +190,7 @@ Coroutine *qemu_coroutine_new(void)
* Set the new stack.
*/
ss.ss_sp = co->stack;
- ss.ss_size = stack_size;
+ ss.ss_size = co->stack_size;
ss.ss_flags = 0;
if (sigaltstack(&ss, &oss) < 0) {
abort();
@@ -251,17 +252,17 @@ Coroutine *qemu_coroutine_new(void)
void qemu_coroutine_delete(Coroutine *co_)
{
- CoroutineUContext *co = DO_UPCAST(CoroutineUContext, base, co_);
+ CoroutineSigAltStack *co = DO_UPCAST(CoroutineSigAltStack, base, co_);
- g_free(co->stack);
+ qemu_free_stack(co->stack, co->stack_size);
g_free(co);
}
CoroutineAction qemu_coroutine_switch(Coroutine *from_, Coroutine *to_,
CoroutineAction action)
{
- CoroutineUContext *from = DO_UPCAST(CoroutineUContext, base, from_);
- CoroutineUContext *to = DO_UPCAST(CoroutineUContext, base, to_);
+ CoroutineSigAltStack *from = DO_UPCAST(CoroutineSigAltStack, base, from_);
+ CoroutineSigAltStack *to = DO_UPCAST(CoroutineSigAltStack, base, to_);
CoroutineThreadState *s = coroutine_get_thread_state();
int ret;
diff --git a/util/coroutine-ucontext.c b/util/coroutine-ucontext.c
index 2bb7e10d4b..6621f3f692 100644
--- a/util/coroutine-ucontext.c
+++ b/util/coroutine-ucontext.c
@@ -34,6 +34,7 @@
typedef struct {
Coroutine base;
void *stack;
+ size_t stack_size;
sigjmp_buf env;
#ifdef CONFIG_VALGRIND_H
@@ -82,7 +83,6 @@ static void coroutine_trampoline(int i0, int i1)
Coroutine *qemu_coroutine_new(void)
{
- const size_t stack_size = 1 << 20;
CoroutineUContext *co;
ucontext_t old_uc, uc;
sigjmp_buf old_env;
@@ -101,17 +101,18 @@ Coroutine *qemu_coroutine_new(void)
}
co = g_malloc0(sizeof(*co));
- co->stack = g_malloc(stack_size);
+ co->stack_size = COROUTINE_STACK_SIZE;
+ co->stack = qemu_alloc_stack(&co->stack_size);
co->base.entry_arg = &old_env; /* stash away our jmp_buf */
uc.uc_link = &old_uc;
uc.uc_stack.ss_sp = co->stack;
- uc.uc_stack.ss_size = stack_size;
+ uc.uc_stack.ss_size = co->stack_size;
uc.uc_stack.ss_flags = 0;
#ifdef CONFIG_VALGRIND_H
co->valgrind_stack_id =
- VALGRIND_STACK_REGISTER(co->stack, co->stack + stack_size);
+ VALGRIND_STACK_REGISTER(co->stack, co->stack + co->stack_size);
#endif
arg.p = co;
@@ -149,7 +150,7 @@ void qemu_coroutine_delete(Coroutine *co_)
valgrind_stack_deregister(co);
#endif
- g_free(co->stack);
+ qemu_free_stack(co->stack, co->stack_size);
g_free(co);
}
diff --git a/util/coroutine-win32.c b/util/coroutine-win32.c
index 02e28e825f..de6bd4fd3e 100644
--- a/util/coroutine-win32.c
+++ b/util/coroutine-win32.c
@@ -71,7 +71,7 @@ static void CALLBACK coroutine_trampoline(void *co_)
Coroutine *qemu_coroutine_new(void)
{
- const size_t stack_size = 1 << 20;
+ const size_t stack_size = COROUTINE_STACK_SIZE;
CoroutineWin32 *co;
co = g_malloc0(sizeof(*co));
diff --git a/util/oslib-posix.c b/util/oslib-posix.c
index f2d4e9e592..aaec1891f5 100644
--- a/util/oslib-posix.c
+++ b/util/oslib-posix.c
@@ -50,6 +50,10 @@
#include "qemu/mmap-alloc.h"
+#ifdef CONFIG_DEBUG_STACK_USAGE
+#include "qemu/error-report.h"
+#endif
+
int qemu_get_thread_id(void)
{
#if defined(__linux__)
@@ -499,3 +503,76 @@ pid_t qemu_fork(Error **errp)
}
return pid;
}
+
+void *qemu_alloc_stack(size_t *sz)
+{
+ void *ptr, *guardpage;
+#ifdef CONFIG_DEBUG_STACK_USAGE
+ void *ptr2;
+#endif
+ size_t pagesz = getpagesize();
+#ifdef _SC_THREAD_STACK_MIN
+ /* avoid stacks smaller than _SC_THREAD_STACK_MIN */
+ long min_stack_sz = sysconf(_SC_THREAD_STACK_MIN);
+ *sz = MAX(MAX(min_stack_sz, 0), *sz);
+#endif
+ /* adjust stack size to a multiple of the page size */
+ *sz = ROUND_UP(*sz, pagesz);
+ /* allocate one extra page for the guard page */
+ *sz += pagesz;
+
+ ptr = mmap(NULL, *sz, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ if (ptr == MAP_FAILED) {
+ abort();
+ }
+
+#if defined(HOST_IA64)
+ /* separate register stack */
+ guardpage = ptr + (((*sz - pagesz) / 2) & ~pagesz);
+#elif defined(HOST_HPPA)
+ /* stack grows up */
+ guardpage = ptr + *sz - pagesz;
+#else
+ /* stack grows down */
+ guardpage = ptr;
+#endif
+ if (mprotect(guardpage, pagesz, PROT_NONE) != 0) {
+ abort();
+ }
+
+#ifdef CONFIG_DEBUG_STACK_USAGE
+ for (ptr2 = ptr + pagesz; ptr2 < ptr + *sz; ptr2 += sizeof(uint32_t)) {
+ *(uint32_t *)ptr2 = 0xdeadbeaf;
+ }
+#endif
+
+ return ptr;
+}
+
+#ifdef CONFIG_DEBUG_STACK_USAGE
+static __thread unsigned int max_stack_usage;
+#endif
+
+void qemu_free_stack(void *stack, size_t sz)
+{
+#ifdef CONFIG_DEBUG_STACK_USAGE
+ unsigned int usage;
+ void *ptr;
+
+ for (ptr = stack + getpagesize(); ptr < stack + sz;
+ ptr += sizeof(uint32_t)) {
+ if (*(uint32_t *)ptr != 0xdeadbeaf) {
+ break;
+ }
+ }
+ usage = sz - (uintptr_t) (ptr - stack);
+ if (usage > max_stack_usage) {
+ error_report("thread %d max stack usage increased from %u to %u",
+ qemu_get_thread_id(), max_stack_usage, usage);
+ max_stack_usage = usage;
+ }
+#endif
+
+ munmap(stack, sz);
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-03 03:07:35 +0000