motorhead/qemu
1
0
Fork 0
mirror of https://github.com/Motorhead1991/qemu.git synced 2025-08-01 23:03:54 -06:00
Code Issues Projects Releases Packages Wiki Activity Actions

tcg: Prepare TB invalidation for lockless TB lookup

Browse source 
When invalidating a translation block, set an invalid flag into the
TranslationBlock structure first.  It is also necessary to check whether
the target TB is still valid after acquiring 'tb_lock' but before calling
tb_add_jump() since TB lookup is to be performed out of 'tb_lock' in
future. Note that we don't have to check 'last_tb'; an already invalidated
TB will not be executed anyway and it is thus safe to patch it.

Suggested-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Paolo Bonzini 2016-07-19 08:36:18 +02:00
parent 118b07308a
commit 6d21e4208f
3 changed files with 8 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

5
cpu-exec.c
View file

@ -241,7 +241,8 @@ static bool tb_cmp(const void *p, const void *d)
if (tb->pc == desc->pc &&
tb->page_addr[0] == desc->phys_page1 &&
tb->cs_base == desc->cs_base &&
tb->flags == desc->flags) {
tb->flags == desc->flags &&
!atomic_read(&tb->invalid)) {
/* check next page if needed */
if (tb->page_addr[1] == -1) {
return true;
@ -352,7 +353,7 @@ static inline TranslationBlock *tb_find_fast(CPUState *cpu,
/* Check if translation buffer has been flushed */
if (cpu->tb_flushed) {
cpu->tb_flushed = false;
} else {
} else if (!tb->invalid) {
tb_add_jump(last_tb, tb_exit, tb);
}
}