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| author | Sergey Fedorov <serge.fdrv@gmail.com> | 2016-08-02 18:27:43 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2016-09-27 11:57:30 +0200 |
| commit | 3359baad36889b83df40b637ed993a4b816c4906 (patch) | |
| tree | 534ac1be2e5bd5466404bb34ac2b7d52e89a0215 /cpu-exec.c | |
| parent | 53f5ed95064fe6807890cd5535445a05d3361bd2 (diff) | |
| download | qemu-3359baad36889b83df40b637ed993a4b816c4906.tar.gz qemu-3359baad36889b83df40b637ed993a4b816c4906.tar.bz2 qemu-3359baad36889b83df40b637ed993a4b816c4906.zip | |
tcg: Make tb_flush() thread safe
Use async_safe_run_on_cpu() to make tb_flush() thread safe. This is
possible now that code generation does not happen in the middle of
execution.
It can happen that multiple threads schedule a safe work to flush the
translation buffer. To keep statistics and debugging output sane, always
check if the translation buffer has already been flushed.
Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
[AJB: minor re-base fixes]
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <1470158864-17651-13-git-send-email-alex.bennee@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'cpu-exec.c')
| -rw-r--r-- | cpu-exec.c | 12 |
1 files changed, 2 insertions, 10 deletions
diff --git a/cpu-exec.c b/cpu-exec.c index 9f4bd0b6dd..8823d23df7 100644 --- a/cpu-exec.c +++ b/cpu-exec.c @@ -204,20 +204,16 @@ static void cpu_exec_nocache(CPUState *cpu, int max_cycles, TranslationBlock *orig_tb, bool ignore_icount) { TranslationBlock *tb; - bool old_tb_flushed; /* Should never happen. We only end up here when an existing TB is too long. */ if (max_cycles > CF_COUNT_MASK) max_cycles = CF_COUNT_MASK; - old_tb_flushed = cpu->tb_flushed; - cpu->tb_flushed = false; tb = tb_gen_code(cpu, orig_tb->pc, orig_tb->cs_base, orig_tb->flags, max_cycles | CF_NOCACHE | (ignore_icount ? CF_IGNORE_ICOUNT : 0)); - tb->orig_tb = cpu->tb_flushed ? NULL : orig_tb; - cpu->tb_flushed |= old_tb_flushed; + tb->orig_tb = orig_tb; /* execute the generated code */ trace_exec_tb_nocache(tb, tb->pc); cpu_tb_exec(cpu, tb); @@ -338,10 +334,7 @@ static inline TranslationBlock *tb_find(CPUState *cpu, tb_lock(); have_tb_lock = true; } - /* Check if translation buffer has been flushed */ - if (cpu->tb_flushed) { - cpu->tb_flushed = false; - } else if (!tb->invalid) { + if (!tb->invalid) { tb_add_jump(last_tb, tb_exit, tb); } } @@ -606,7 +599,6 @@ int cpu_exec(CPUState *cpu) break; } - atomic_mb_set(&cpu->tb_flushed, false); /* reset before first TB lookup */ for(;;) { cpu_handle_interrupt(cpu, &last_tb); tb = tb_find(cpu, last_tb, tb_exit); |