Add a command line parameter to not dump guest memory in the core dump, the
command line is: -dont-dump-guest. This brought the core dump down from
383MB to 13 MB on a 1GB guest.
Signed-off-by: Jason Baron <jba...@redhat.com>
---
exec.c | 13 +++++++++++++
osdep.h | 7 +++++++
qemu-options.hx | 5 +++++
sysemu.h | 1 +
vl.c | 4 ++++
5 files changed, 30 insertions(+), 0 deletions(-)
diff --git a/exec.c b/exec.c
index 0607c9b..f9d2b93 100644
--- a/exec.c
+++ b/exec.c
@@ -35,6 +35,7 @@
#include "qemu-timer.h"
#include "memory.h"
#include "exec-memory.h"
+#include "sysemu.h"
#if defined(CONFIG_USER_ONLY)
#include <qemu.h>
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
@@ -2605,6 +2606,7 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void
*host,
MemoryRegion *mr)
{
RAMBlock *new_block;
+ int ret;
size = TARGET_PAGE_ALIGN(size);
new_block = g_malloc0(sizeof(*new_block));
@@ -2659,6 +2661,17 @@ ram_addr_t qemu_ram_alloc_from_ptr(ram_addr_t size, void
*host,
memset(ram_list.phys_dirty + (new_block->offset >> TARGET_PAGE_BITS),
0xff, size >> TARGET_PAGE_BITS);
+
+ /* Use MADV_DONTDUMP, if user doesn't want the guest memory in the core */
+ if (dont_dump_guest) {
+ ret = qemu_madvise(new_block->host, size, QEMU_MADV_DONTDUMP);
+ if (ret) {
+ perror("qemu_madvise");
+ fprintf(stderr, "madvise doesn't support MADV_DONTDUMP, "
+ "but -dont-dump-guest-core specified\n");
+ }
+ }
+
if (kvm_enabled())
kvm_setup_guest_memory(new_block->host, size);
diff --git a/osdep.h b/osdep.h
index 9db8766..db275f2 100644
--- a/osdep.h
+++ b/osdep.h
@@ -100,6 +100,11 @@ void qemu_vfree(void *ptr);
#else
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
#endif
+#ifdef MADV_DONTDUMP
+#define QEMU_MADV_DONTDUMP MADV_DONTDUMP
+#else
+#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
+#endif
#elif defined(CONFIG_POSIX_MADVISE)
@@ -107,6 +112,7 @@ void qemu_vfree(void *ptr);
#define QEMU_MADV_DONTNEED POSIX_MADV_DONTNEED
#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
+#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
#else /* no-op */
@@ -114,6 +120,7 @@ void qemu_vfree(void *ptr);
#define QEMU_MADV_DONTNEED QEMU_MADV_INVALID
#define QEMU_MADV_DONTFORK QEMU_MADV_INVALID
#define QEMU_MADV_MERGEABLE QEMU_MADV_INVALID
+#define QEMU_MADV_DONTDUMP QEMU_MADV_INVALID
#endif
diff --git a/qemu-options.hx b/qemu-options.hx
index a169792..ae12cc6 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -2724,6 +2724,11 @@ DEF("qtest-log", HAS_ARG, QEMU_OPTION_qtest_log,
"-qtest-log LOG specify tracing options\n",
QEMU_ARCH_ALL)
+DEF("dont-dump-guest", 0, QEMU_OPTION_dont_dump_guest,
+ "-dont-dump-guest\n"
+ " do not dump guest core\n",
+ QEMU_ARCH_ALL)
+
HXCOMM This is the last statement. Insert new options before this line!
STEXI
@end table
diff --git a/sysemu.h b/sysemu.h
index bc2c788..f738f34 100644
--- a/sysemu.h
+++ b/sysemu.h
@@ -131,6 +131,7 @@ extern uint8_t *boot_splash_filedata;
extern int boot_splash_filedata_size;
extern uint8_t qemu_extra_params_fw[2];
extern QEMUClock *rtc_clock;
+extern int dont_dump_guest;
#define MAX_NODES 64
extern int nb_numa_nodes;
diff --git a/vl.c b/vl.c
index ae91a8a..6259c21 100644
--- a/vl.c
+++ b/vl.c
@@ -232,6 +232,7 @@ int boot_menu;
uint8_t *boot_splash_filedata;
int boot_splash_filedata_size;
uint8_t qemu_extra_params_fw[2];
+int dont_dump_guest;
typedef struct FWBootEntry FWBootEntry;
@@ -3191,6 +3192,9 @@ int main(int argc, char **argv, char **envp)
case QEMU_OPTION_qtest_log:
qtest_log = optarg;
break;
+ case QEMU_OPTION_dont_dump_guest:
+ dont_dump_guest = 1;
+ break;
default:
os_parse_cmd_args(popt->index, optarg);
}
--
1.7.1
