On 2/12/25 5:13 PM, Stefan Hajnoczi wrote:
On Tue, Feb 11, 2025 at 5:52 PM Peter Xu <pet...@redhat.com> wrote:
From: Daniil Tatianin <d-tatia...@yandex-team.ru>
This will be used in the following commits to make it possible to only
lock memory on fault instead of right away.
Hi Peter and Daniil,
Please take a look at this CI failure:
https://gitlab.com/qemu-project/qemu/-/jobs/9117106042#L3603
Thanks,
Stefan
Looks like MCL_ONFAULT is linux-only, I guess I'll have to have add
something similar to HAVE_MLOCKALL and put this under an ifdef.
Thank you
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsement...@yandex-team.ru>
Reviewed-by: Peter Xu <pet...@redhat.com>
Signed-off-by: Daniil Tatianin <d-tatia...@yandex-team.ru>
Link:
https://lore.kernel.org/r/20250123131944.391886-2-d-tatia...@yandex-team.ru
Signed-off-by: Peter Xu <pet...@redhat.com>
---
include/system/os-posix.h | 2 +-
include/system/os-win32.h | 3 ++-
migration/postcopy-ram.c | 2 +-
os-posix.c | 10 ++++++++--
system/vl.c | 2 +-
5 files changed, 13 insertions(+), 6 deletions(-)
diff --git a/include/system/os-posix.h b/include/system/os-posix.h
index b881ac6c6f..ce5b3bccf8 100644
--- a/include/system/os-posix.h
+++ b/include/system/os-posix.h
@@ -53,7 +53,7 @@ bool os_set_runas(const char *user_id);
void os_set_chroot(const char *path);
void os_setup_limits(void);
void os_setup_post(void);
-int os_mlock(void);
+int os_mlock(bool on_fault);
/**
* qemu_alloc_stack:
diff --git a/include/system/os-win32.h b/include/system/os-win32.h
index b82a5d3ad9..cd61d69e10 100644
--- a/include/system/os-win32.h
+++ b/include/system/os-win32.h
@@ -123,8 +123,9 @@ static inline bool is_daemonized(void)
return false;
}
-static inline int os_mlock(void)
+static inline int os_mlock(bool on_fault)
{
+ (void)on_fault;
return -ENOSYS;
}
diff --git a/migration/postcopy-ram.c b/migration/postcopy-ram.c
index 6a6da6ba7f..fc4d8a10df 100644
--- a/migration/postcopy-ram.c
+++ b/migration/postcopy-ram.c
@@ -652,7 +652,7 @@ int postcopy_ram_incoming_cleanup(MigrationIncomingState
*mis)
}
if (enable_mlock) {
- if (os_mlock() < 0) {
+ if (os_mlock(false) < 0) {
error_report("mlock: %s", strerror(errno));
/*
* It doesn't feel right to fail at this point, we have a valid
diff --git a/os-posix.c b/os-posix.c
index 9cce55ff2f..48afb2990d 100644
--- a/os-posix.c
+++ b/os-posix.c
@@ -327,18 +327,24 @@ void os_set_line_buffering(void)
setvbuf(stdout, NULL, _IOLBF, 0);
}
-int os_mlock(void)
+int os_mlock(bool on_fault)
{
#ifdef HAVE_MLOCKALL
int ret = 0;
+ int flags = MCL_CURRENT | MCL_FUTURE;
- ret = mlockall(MCL_CURRENT | MCL_FUTURE);
+ if (on_fault) {
+ flags |= MCL_ONFAULT;
+ }
+
+ ret = mlockall(flags);
if (ret < 0) {
error_report("mlockall: %s", strerror(errno));
}
return ret;
#else
+ (void)on_fault;
return -ENOSYS;
#endif
}
diff --git a/system/vl.c b/system/vl.c
index 9c6942c6cf..e94fc7ea35 100644
--- a/system/vl.c
+++ b/system/vl.c
@@ -797,7 +797,7 @@ static QemuOptsList qemu_run_with_opts = {
static void realtime_init(void)
{
if (enable_mlock) {
- if (os_mlock() < 0) {
+ if (os_mlock(false) < 0) {
error_report("locking memory failed");
exit(1);
}
--
2.47.0
