| Message ID | 64c8e95b25f58c5e05c98765dab2bc8eb9b1483d.camel@linux.ibm.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v5,01/17] powerpc/powernv/vas: Release reference to tgid during window close | expand |
Excerpts from Haren Myneni's message of June 13, 2021 9:00 pm: > > PowerVM introduces two different type of credits: Default and Quality > of service (QoS). > > The total number of default credits available on each LPAR depends > on CPU resources configured. But these credits can be shared or > over-committed across LPARs in shared mode which can result in > paste command failure (RMA_busy). To avoid NX HW contention, the > hypervisor ntroduces QoS credit type which makes sure guaranteed > access to NX esources. The system admins can assign QoS credits > or each LPAR via HMC. > > Default credit type is used to allocate a VAS window by default as > on PowerVM implementation. But the process can pass > VAS_TX_WIN_FLAG_QOS_CREDIT flag with VAS_TX_WIN_OPEN ioctl to open > QoS type window. > > Signed-off-by: Haren Myneni <haren@linux.ibm.com> Flag name looks good now. Again I don't have the spec, so Acked-by: Nicholas Piggin <npiggin@gmail.com> Thanks, Nick > --- > arch/powerpc/include/uapi/asm/vas-api.h | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/powerpc/include/uapi/asm/vas-api.h b/arch/powerpc/include/uapi/asm/vas-api.h > index ebd4b2424785..7c81301ecdba 100644 > --- a/arch/powerpc/include/uapi/asm/vas-api.h > +++ b/arch/powerpc/include/uapi/asm/vas-api.h > @@ -13,11 +13,15 @@ > #define VAS_MAGIC 'v' > #define VAS_TX_WIN_OPEN _IOW(VAS_MAGIC, 0x20, struct vas_tx_win_open_attr) > > +/* Flags to VAS TX open window ioctl */ > +/* To allocate a window with QoS credit, otherwise use default credit */ > +#define VAS_TX_WIN_FLAG_QOS_CREDIT 0x0000000000000001 > + > struct vas_tx_win_open_attr { > __u32 version; > __s16 vas_id; /* specific instance of vas or -1 for default */ > __u16 reserved1; > - __u64 flags; /* Future use */ > + __u64 flags; > __u64 reserved2[6]; > }; > > -- > 2.18.2 > > >
diff --git a/arch/powerpc/include/uapi/asm/vas-api.h b/arch/powerpc/include/uapi/asm/vas-api.h index ebd4b2424785..7c81301ecdba 100644 --- a/arch/powerpc/include/uapi/asm/vas-api.h +++ b/arch/powerpc/include/uapi/asm/vas-api.h @@ -13,11 +13,15 @@ #define VAS_MAGIC 'v' #define VAS_TX_WIN_OPEN _IOW(VAS_MAGIC, 0x20, struct vas_tx_win_open_attr) +/* Flags to VAS TX open window ioctl */ +/* To allocate a window with QoS credit, otherwise use default credit */ +#define VAS_TX_WIN_FLAG_QOS_CREDIT 0x0000000000000001 + struct vas_tx_win_open_attr { __u32 version; __s16 vas_id; /* specific instance of vas or -1 for default */ __u16 reserved1; - __u64 flags; /* Future use */ + __u64 flags; __u64 reserved2[6]; };
PowerVM introduces two different type of credits: Default and Quality of service (QoS). The total number of default credits available on each LPAR depends on CPU resources configured. But these credits can be shared or over-committed across LPARs in shared mode which can result in paste command failure (RMA_busy). To avoid NX HW contention, the hypervisor ntroduces QoS credit type which makes sure guaranteed access to NX esources. The system admins can assign QoS credits or each LPAR via HMC. Default credit type is used to allocate a VAS window by default as on PowerVM implementation. But the process can pass VAS_TX_WIN_FLAG_QOS_CREDIT flag with VAS_TX_WIN_OPEN ioctl to open QoS type window. Signed-off-by: Haren Myneni <haren@linux.ibm.com> --- arch/powerpc/include/uapi/asm/vas-api.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)