Re: [Qemu-devel] [PATCH] fix the memory leak for share hugepage

[Linhaifeng <haifeng.lin@huawei.com>]

On 2014/10/17 16:43, zhanghailiang wrote:
> On 2014/10/17 16:27, haifeng.lin@huawei.com wrote:
>> From: linhaifeng <haifeng.lin@huawei.com>
>>
>> The VM start with share hugepage should close the hugefile fd
>> when exit.Because the hugepage fd may be send to other process
>> e.g vhost-user If qemu not close the fd the other process can
>> not free the hugepage otherwise exit process,this is ugly,so
>> qemu should close all shared fd when exit.
>>
>> Signed-off-by: linhaifeng <haifeng.lin@huawei.com>
>> ---
>>   exec.c | 12 ++++++++++++
>>   vl.c   |  7 +++++++
>>   2 files changed, 19 insertions(+)
>>
>> diff --git a/exec.c b/exec.c
>> index 759055d..d120b73 100644
>> --- a/exec.c
>> +++ b/exec.c
>> @@ -1535,6 +1535,18 @@ void qemu_ram_remap(ram_addr_t addr, ram_addr_t length)
>>           }
>>       }
>>   }
>> +
>> +void qemu_close_all_ram_fd(void)
>> +{
>> +    RAMBlock *block;
>> +
>> +    qemu_mutex_lock_ramlist();
>> +    QTAILQ_FOREACH(block, &ram_list.blocks, next) {
>> +        close(block->fd);
>> +    }
>> +    qemu_mutex_unlock_ramlist();
>> +}
>> +
>>   #endif /* !_WIN32 */
>>
>>   int qemu_get_ram_fd(ram_addr_t addr)
>> diff --git a/vl.c b/vl.c
>> index aee73e1..0b78f3f 100644
>> --- a/vl.c
>> +++ b/vl.c
>> @@ -1658,6 +1658,7 @@ static int qemu_shutdown_requested(void)
>>       return r;
>>   }
>>
>> +extern void qemu_close_all_ram_fd(void);
>>   static void qemu_kill_report(void)
>>   {
>>       if (!qtest_driver() && shutdown_signal != -1) {
>> @@ -1671,6 +1672,12 @@ static void qemu_kill_report(void)
>>               fprintf(stderr, " from pid " FMT_pid "\n", shutdown_pid);
>>           }
>>           shutdown_signal = -1;
>> +
>> +        /* Close all ram fd when exit. If the ram is shared by othter process
> 
> s/othter/other/
> 

OK.thank you.

>> +         * e.g vhost-user, it can free the hugepage by close fd after qemu exit,
>> +         * otherwise the process have to exit to free hugepage.
>> +         */
>> +        qemu_close_all_ram_fd();
>>       }
>>   }
>>
>>
> 
> 
> 
> .
> 

-- 
Regards,
Haifeng