Re: [Qemu-devel] [PATCH v1 3/6] qga: guest_suspend: decoupling pm-utils and sys logic

[Daniel Henrique Barboza <danielhb413@gmail.com>]

Hi,

On 06/19/2018 08:23 PM, Marc-André Lureau wrote:
> Hi
>
> On Tue, Jun 19, 2018 at 9:38 PM, Daniel Henrique Barboza
> <danielhb413@gmail.com> wrote:
>> Following the same logic of the previous patch, let's also
>> decouple the suspend logic from guest_suspend into specialized
>> functions, one for each strategy we support at this moment.
>>
>> Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com>
>> ---
>>   qga/commands-posix.c | 170 +++++++++++++++++++++++++++----------------
>>   1 file changed, 108 insertions(+), 62 deletions(-)
>>
>> diff --git a/qga/commands-posix.c b/qga/commands-posix.c
>> index 89ffd8dc88..a2870f9ab9 100644
>> --- a/qga/commands-posix.c
>> +++ b/qga/commands-posix.c
>> @@ -1509,6 +1509,65 @@ out:
>>       return ret;
>>   }
>>
>> +static void pmutils_suspend(int suspend_mode, Error **errp)
>> +{
>> +    Error *local_err = NULL;
>> +    const char *pmutils_bin;
>> +    char *pmutils_path;
>> +    pid_t pid;
>> +    int status;
>> +
>> +    switch (suspend_mode) {
>> +
>> +    case SUSPEND_MODE_DISK:
>> +        pmutils_bin = "pm-hibernate";
>> +        break;
>> +    case SUSPEND_MODE_RAM:
>> +        pmutils_bin = "pm-suspend";
>> +        break;
>> +    case SUSPEND_MODE_HYBRID:
>> +        pmutils_bin = "pm-suspend-hybrid";
>> +        break;
>> +    default:
>> +        error_setg(errp, "unknown guest suspend mode");
>> +        return;
>> +    }
>> +
>> +    pmutils_path = g_find_program_in_path(pmutils_bin);
>> +    if (!pmutils_path) {
>> +        error_setg(errp, "the helper program '%s' was not found", pmutils_bin);
>> +        return;
>> +    }
>> +
>> +    pid = fork();
>> +    if (!pid) {
>> +        setsid();
>> +        execle(pmutils_path, pmutils_bin, NULL, environ);
>> +        /*
>> +         * If we get here execle() has failed.
>> +         */
>> +        _exit(EXIT_FAILURE);
>> +    } else if (pid < 0) {
>> +        error_setg_errno(errp, errno, "failed to create child process");
>> +        goto out;
>> +    }
>> +
>> +    ga_wait_child(pid, &status, &local_err);
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +        goto out;
>> +    }
>> +
>> +    if (WEXITSTATUS(status)) {
>> +        error_setg(errp,
>> +                   "the helper program '%s' returned an unexpected exit status"
>> +                   " code (%d)", pmutils_path, WEXITSTATUS(status));
>> +    }
>> +
>> +out:
>> +    g_free(pmutils_path);
>> +}
>> +
>>   static bool linux_sys_state_supports_mode(int suspend_mode, Error **errp)
>>   {
>>       const char *sysfile_str;
>> @@ -1545,64 +1604,28 @@ static bool linux_sys_state_supports_mode(int suspend_mode, Error **errp)
>>       return false;
>>   }
>>
>> -static void bios_supports_mode(int suspend_mode, Error **errp)
>> -{
>> -    Error *local_err = NULL;
>> -    bool ret;
>> -
>> -    ret = pmutils_supports_mode(suspend_mode, &local_err);
>> -    if (ret) {
>> -        return;
>> -    }
>> -    if (local_err) {
>> -        error_propagate(errp, local_err);
>> -        return;
>> -    }
>> -    ret = linux_sys_state_supports_mode(suspend_mode, errp);
>> -    if (!ret) {
>> -        error_setg(errp,
>> -                   "the requested suspend mode is not supported by the guest");
>> -        return;
>> -    }
>> -}
>> -
>> -static void guest_suspend(int suspend_mode, Error **errp)
>> +static void linux_sys_state_suspend(int suspend_mode, Error **errp)
>>   {
>>       Error *local_err = NULL;
>> -    const char *pmutils_bin, *sysfile_str;
>> -    char *pmutils_path;
>> +    const char *sysfile_str;
>>       pid_t pid;
>>       int status;
>>
>> -    bios_supports_mode(suspend_mode, &local_err);
>> -    if (local_err) {
>> -        error_propagate(errp, local_err);
>> -        return;
>> -    }
>> -
>>       switch (suspend_mode) {
>>
>>       case SUSPEND_MODE_DISK:
>> -        pmutils_bin = "pm-hibernate";
>>           sysfile_str = "disk";
>>           break;
>>       case SUSPEND_MODE_RAM:
>> -        pmutils_bin = "pm-suspend";
>>           sysfile_str = "mem";
>>           break;
>> -    case SUSPEND_MODE_HYBRID:
>> -        pmutils_bin = "pm-suspend-hybrid";
>> -        sysfile_str = NULL;
>> -        break;
>>       default:
>>           error_setg(errp, "unknown guest suspend mode");
>>           return;
>>       }
>>
>> -    pmutils_path = g_find_program_in_path(pmutils_bin);
>> -
>>       pid = fork();
>> -    if (pid == 0) {
>> +    if (!pid) {
>>           /* child */
>>           int fd;
>>
>> @@ -1611,19 +1634,6 @@ static void guest_suspend(int suspend_mode, Error **errp)
>>           reopen_fd_to_null(1);
>>           reopen_fd_to_null(2);
>>
>> -        if (pmutils_path) {
>> -            execle(pmutils_path, pmutils_bin, NULL, environ);
>> -        }
>> -
>> -        /*
>> -         * If we get here either pm-utils is not installed or execle() has
>> -         * failed. Let's try the manual method if the caller wants it.
>> -         */
>> -
>> -        if (!sysfile_str) {
>> -            _exit(EXIT_FAILURE);
>> -        }
>> -
>>           fd = open(LINUX_SYS_STATE_FILE, O_WRONLY);
>>           if (fd < 0) {
>>               _exit(EXIT_FAILURE);
>> @@ -1636,27 +1646,63 @@ static void guest_suspend(int suspend_mode, Error **errp)
>>           _exit(EXIT_SUCCESS);
>>       } else if (pid < 0) {
>>           error_setg_errno(errp, errno, "failed to create child process");
>> -        goto out;
>> +        return;
>>       }
>>
>>       ga_wait_child(pid, &status, &local_err);
>>       if (local_err) {
>>           error_propagate(errp, local_err);
>> -        goto out;
>> -    }
>> -
>> -    if (!WIFEXITED(status)) {
>> -        error_setg(errp, "child process has terminated abnormally");
>> -        goto out;
>> +        return;
>>       }
>>
>>       if (WEXITSTATUS(status)) {
>>           error_setg(errp, "child process has failed to suspend");
>> -        goto out;
>>       }
>>
>> -out:
>> -    g_free(pmutils_path);
>> +}
>> +
>> +static void bios_supports_mode(int suspend_mode, Error **errp)
>> +{
>> +    Error *local_err = NULL;
>> +    bool ret;
>> +
>> +    ret = pmutils_supports_mode(suspend_mode, &local_err);
>> +    if (ret) {
>> +        return;
>> +    }
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +        return;
>> +    }
>> +    ret = linux_sys_state_supports_mode(suspend_mode, errp);
>> +    if (!ret) {
>> +        error_setg(errp,
>> +                   "the requested suspend mode is not supported by the guest");
>> +        return;
>> +    }
>> +}
>> +
>> +static void guest_suspend(int suspend_mode, Error **errp)
>> +{
>> +    Error *local_err = NULL;
>> +
>> +    bios_supports_mode(suspend_mode, &local_err);
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +        return;
>> +    }
>> +
>> +    pmutils_suspend(suspend_mode, &local_err);
>> +    if (!local_err) {
>> +        return;
>> +    }
>> +
>> +    local_err = NULL;
> You should error_free(). Same in later patches.

Thanks, I've fixed it for v2.


Daniel

>
>> +
>> +    linux_sys_state_suspend(suspend_mode, &local_err);
>> +    if (local_err) {
>> +        error_propagate(errp, local_err);
>> +    }
>>   }
>>
>>   void qmp_guest_suspend_disk(Error **errp)
>> --
>> 2.17.1
>>
>>
>
>