motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-07-26 20:03:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

plugins: add [pre|post]fork helpers to linux-user

Browse source 
Special care needs to be taken in ensuring locks are in a consistent
state across fork events. Add helpers so the plugin system can ensure
that.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Fixes: https://gitlab.com/qemu-project/qemu/-/issues/358
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Tested-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221004115221.2174499-1-alex.bennee@linaro.org>
This commit is contained in:
Alex Bennée 2022-10-04 12:52:21 +01:00
parent 37e62694e4
commit f7e15affa8
3 changed files with 46 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

20
plugins/core.c
View file

@ -526,6 +526,26 @@ void qemu_plugin_user_exit(void)
qemu_plugin_atexit_cb();
}
/*
* Helpers for *-user to ensure locks are sane across fork() events.
*/
void qemu_plugin_user_prefork_lock(void)
{
qemu_rec_mutex_lock(&plugin.lock);
}
void qemu_plugin_user_postfork(bool is_child)
{
if (is_child) {
/* should we just reset via plugin_init? */
qemu_rec_mutex_init(&plugin.lock);
} else {
qemu_rec_mutex_unlock(&plugin.lock);
}
}
/*
* Call this function after longjmp'ing to the main loop. It's possible that the
* last instruction of a TB might have used helpers, and therefore the