yeah Shuah~ thanks for your reply
For this issue, not meaning "current CPU frequency" but "boost state
support--->Active" during
"cpupower frequency-info" command as below:
boost state support:
Supported: yes
Active: yes/no
I think the state returned from the command for amd cpu (family < 0x17) should
be like as below:
as non-root Active state:
Active: Error while evaluating Boost Capabilities on CPU xx --
are you root?
as root Active state:
Active: yes (if supported)
no (if not supprted)
I don't wanna see the state returned like below:
as non-root Active state:
Active: yes
as root Active state:
Active: yes (if supported)
no (if not supprted)
I will paste the related code by detailed for showing the issue:
if amd cpu family < 0x17 , will run amd_pci_get_num_boost_states
function:
-----------------------------------------------------
/linux/tools/power/cpupower/utils/helper/misc.c
if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_CPB) {
*support = 1;
/* AMD Family 0x17 does not utilize PCI D18F4 like prior
* families and has no fixed discrete boost states but
* has Hardware determined variable increments instead.
*/
if (cpupower_cpu_info.caps & CPUPOWER_CAP_AMD_CPB_MSR) {
if (!read_msr(cpu, MSR_AMD_HWCR, &val)) {
if (!(val & CPUPOWER_AMD_CPBDIS))
*active = 1;
}
} else {
ret = amd_pci_get_num_boost_states(active, states);
if (ret)
return ret;
}
---------------------------------------------------
/linux/tools/power/cpupower/utils/helper/amd.c
amd_pci_get_num_boost_states:
val = pci_read_byte(device, 0x15c);
if (val & 3)
*active = 1;
else
----------------------------------------------------
pci_read_byte will memset val to 0xff if caller has no permission to access to
read from pci_dev
but for amd_pci_get_num_boost_states, active state will set 1 meaning "yes". I
believe that active
state should return negative value to caller function meaning "have no
permission" will showing "
Error while evaluating Boost Capabilities on CPU xx -- are you root?"
----------------------------------------------------
static inline void
pci_read_data(struct pci_dev *d, void *buf, int pos, int len)
{
if (pos & (len-1))
d->access->error("Unaligned read: pos=%02x, len=%d", pos, len);
if (pos + len <= d->cache_len)
memcpy(buf, d->cache + pos, len);
else if (!d->methods->read(d, pos, buf, len))
memset(buf, 0xff, len);
}
byte
pci_read_byte(struct pci_dev *d, int pos)
{
byte buf;
pci_read_data(d, &buf, pos, 1);
return buf;
}
----------------------------------------------------
在 2021/3/24 下午6:27, xufuhai 写道:
> From: xufuhai <xufu...@kuaishou.com>
>
> For the old AMD processor (family < 0x17), cpupower will call the
> amd_pci_get_num_boost_states function, but for the non-root user
> pci_read_byte function (implementation comes from the psutil library),
> val will be set to 0xff, indicating that there is no read function
> callback. At this time, the original logic will set the cpupower turbo
> active state to yes. This is an obvious issue~
>
> Reproduce procedure:
> cpupower frequency-info
>
> Signed-off-by: xufuhai <xufu...@kuaishou.com>
> Signed-off-by: chenguanqiao <chenguanq...@kuaishou.com>
> Signed-off-by: lishujin <lishu...@kuaishou.com>
> ---
> tools/power/cpupower/utils/helpers/amd.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/tools/power/cpupower/utils/helpers/amd.c
> b/tools/power/cpupower/utils/helpers/amd.c
> index 97f2c857048e..6f9504906afa 100644
> --- a/tools/power/cpupower/utils/helpers/amd.c
> +++ b/tools/power/cpupower/utils/helpers/amd.c
> @@ -137,6 +137,13 @@ int amd_pci_get_num_boost_states(int *active, int
> *states)
> return -ENODEV;
>
> val = pci_read_byte(device, 0x15c);
> +
> + /* If val is 0xff, meaning has no permisson to
> + * get the boost states, return -1
> + */
> + if (val == 0xff)
> + return -1;
> +
> if (val & 3)
> *active = 1;
> else
>
