From: Jerin Jacob <jerinjacobk@gmail.com>
To: Feifei Wang <Feifei.Wang2@arm.com>
Cc: "Ruifeng Wang" <Ruifeng.Wang@arm.com>, dpdk-dev <dev@dpdk.org>,
nd <nd@arm.com>,
"Ananyev, Konstantin" <konstantin.ananyev@intel.com>,
"Stephen Hemminger" <stephen@networkplumber.org>,
"David Marchand" <david.marchand@redhat.com>,
"thomas@monjalon.net" <thomas@monjalon.net>,
"Mattias Rönnblom" <mattias.ronnblom@ericsson.com>
Subject: Re: [dpdk-dev] [PATCH v7 1/5] eal: add new definitions for wait scheme
Date: Thu, 28 Oct 2021 13:21:05 +0530 [thread overview]
Message-ID: <CALBAE1MKjV+=fHB1Sy55tYyN-xngsqs5Xj=3dFV6EuoLK+WFLA@mail.gmail.com> (raw)
In-Reply-To: <DB9PR08MB6923FB43F610761CAE5EAB19C8869@DB9PR08MB6923.eurprd08.prod.outlook.com>
On Thu, Oct 28, 2021 at 1:11 PM Feifei Wang <Feifei.Wang2@arm.com> wrote:
>
>
>
> > -----邮件原件-----
> > 发件人: Jerin Jacob <jerinjacobk@gmail.com>
> > 发送时间: Thursday, October 28, 2021 3:16 PM
> > 收件人: Feifei Wang <Feifei.Wang2@arm.com>
> > 抄送: Ruifeng Wang <Ruifeng.Wang@arm.com>; dpdk-dev <dev@dpdk.org>;
> > nd <nd@arm.com>; Ananyev, Konstantin <konstantin.ananyev@intel.com>;
> > Stephen Hemminger <stephen@networkplumber.org>; David Marchand
> > <david.marchand@redhat.com>; thomas@monjalon.net; Mattias Rönnblom
> > <mattias.ronnblom@ericsson.com>
> > 主题: Re: [PATCH v7 1/5] eal: add new definitions for wait scheme
> >
> > On Thu, Oct 28, 2021 at 12:26 PM Feifei Wang <feifei.wang2@arm.com>
> > wrote:
> > >
> > > Introduce macros as generic interface for address monitoring.
> > > For different size, encapsulate '__LOAD_EXC_16', '__LOAD_EXC_32'
> > > and '__LOAD_EXC_64' into a new macro '__LOAD_EXC'.
> > >
> > > Furthermore, to prevent compilation warning in arm:
> > > ----------------------------------------------
> > > 'warning: implicit declaration of function ...'
> > > ----------------------------------------------
> > > Delete 'undef' constructions for '__LOAD_EXC_xx', '__SEVL' and '__WFE'.
> > > And add ‘__RTE_ARM’ for these macros to fix the namespace.
> > >
> > > This is because original macros are undefine at the end of the file.
> > > If new macro 'rte_wait_event' calls them in other files, they will be
> > > seen as 'not defined'.
> > >
> > > Signed-off-by: Feifei Wang <feifei.wang2@arm.com>
> > > Reviewed-by: Ruifeng Wang <ruifeng.wang@arm.com>
> > > ---
> >
> > > +static __rte_always_inline void
> > > +rte_wait_until_equal_16(volatile uint16_t *addr, uint16_t expected,
> > > + int memorder)
> > > +{
> > > + uint16_t value;
> > > +
> > > + assert(memorder == __ATOMIC_ACQUIRE || memorder ==
> > > + __ATOMIC_RELAXED);
> >
> > Assert is not good in the library, Why not RTE_BUILD_BUG_ON here
> [Feifei] This line is the original code which has nothing to do with this patch,
> I can change it in the next version.
> >
> >
> > > +
> > > + __RTE_ARM_LOAD_EXC_16(addr, value, memorder)
> > > if (value != expected) {
> > > - __SEVL()
> > > + __RTE_ARM_SEVL()
> > > do {
> > > - __WFE()
> > > - __LOAD_EXC_16(addr, value, memorder)
> > > + __RTE_ARM_WFE()
> > > + __RTE_ARM_LOAD_EXC_16(addr, value, memorder)
> > > } while (value != expected);
> > > }
> > > -#undef __LOAD_EXC_16
> > > }
> > >
> > > static __rte_always_inline void
> > > @@ -77,34 +124,14 @@ rte_wait_until_equal_32(volatile uint32_t *addr,
> > > uint32_t expected,
> > >
> > > assert(memorder == __ATOMIC_ACQUIRE || memorder ==
> > > __ATOMIC_RELAXED);
> > >
> > > - /*
> > > - * Atomic exclusive load from addr, it returns the 32-bit content of
> > > - * *addr while making it 'monitored',when it is written by someone
> > > - * else, the 'monitored' state is cleared and a event is generated
> > > - * implicitly to exit WFE.
> > > - */
> > > -#define __LOAD_EXC_32(src, dst, memorder) { \
> > > - if (memorder == __ATOMIC_RELAXED) { \
> > > - asm volatile("ldxr %w[tmp], [%x[addr]]" \
> > > - : [tmp] "=&r" (dst) \
> > > - : [addr] "r"(src) \
> > > - : "memory"); \
> > > - } else { \
> > > - asm volatile("ldaxr %w[tmp], [%x[addr]]" \
> > > - : [tmp] "=&r" (dst) \
> > > - : [addr] "r"(src) \
> > > - : "memory"); \
> > > - } }
> > > -
> > > - __LOAD_EXC_32(addr, value, memorder)
> > > + __RTE_ARM_LOAD_EXC_32(addr, value, memorder)
> > > if (value != expected) {
> > > - __SEVL()
> > > + __RTE_ARM_SEVL()
> > > do {
> > > - __WFE()
> > > - __LOAD_EXC_32(addr, value, memorder)
> > > + __RTE_ARM_WFE()
> > > + __RTE_ARM_LOAD_EXC_32(addr, value, memorder)
> > > } while (value != expected);
> > > }
> > > -#undef __LOAD_EXC_32
> > > }
> > >
> > > static __rte_always_inline void
> > > @@ -115,38 +142,33 @@ rte_wait_until_equal_64(volatile uint64_t *addr,
> > > uint64_t expected,
> > >
> > > assert(memorder == __ATOMIC_ACQUIRE || memorder ==
> > > __ATOMIC_RELAXED);
> >
> > remove assert and change to BUILD_BUG_ON
> [Feifei] OK
> >
> > >
> > > - /*
> > > - * Atomic exclusive load from addr, it returns the 64-bit content of
> > > - * *addr while making it 'monitored',when it is written by someone
> > > - * else, the 'monitored' state is cleared and a event is generated
> > > - * implicitly to exit WFE.
> > > - */
> > > -#define __LOAD_EXC_64(src, dst, memorder) { \
> > > - if (memorder == __ATOMIC_RELAXED) { \
> > > - asm volatile("ldxr %x[tmp], [%x[addr]]" \
> > > - : [tmp] "=&r" (dst) \
> > > - : [addr] "r"(src) \
> > > - : "memory"); \
> > > - } else { \
> > > - asm volatile("ldaxr %x[tmp], [%x[addr]]" \
> > > - : [tmp] "=&r" (dst) \
> > > - : [addr] "r"(src) \
> > > - : "memory"); \
> > > - } }
> > > -
> > > - __LOAD_EXC_64(addr, value, memorder)
> > > + __RTE_ARM_LOAD_EXC_64(addr, value, memorder)
> > > if (value != expected) {
> > > - __SEVL()
> > > + __RTE_ARM_SEVL()
> > > do {
> > > - __WFE()
> > > - __LOAD_EXC_64(addr, value, memorder)
> > > + __RTE_ARM_WFE()
> > > + __RTE_ARM_LOAD_EXC_64(addr, value, memorder)
> > > } while (value != expected);
> > > }
> > > }
> > > -#undef __LOAD_EXC_64
> > >
> > > -#undef __SEVL
> > > -#undef __WFE
> > > +#define rte_wait_event(addr, mask, cond, expected, memorder) \
> > > +do { \
> > > + RTE_BUILD_BUG_ON(!__builtin_constant_p(memorder)); \
> > > + RTE_BUILD_BUG_ON(memorder != __ATOMIC_ACQUIRE &&
> > \
> > > + memorder != __ATOMIC_RELAXED); \
> > > + uint32_t size = sizeof(*(addr)) << 3;
> >
> > Add const
> [Feifei] OK.
> > > + typeof(*(addr)) expected_value = (expected); \
> > > + typeof(*(addr)) value = 0;
> >
> > Why zero assignment
> I will delete this initialization.
> > \
> > > + __RTE_ARM_LOAD_EXC((addr), value, memorder, size) \
> >
> > Assert is not good in the library, Why not RTE_BUILD_BUG_ON here
> [Feifei] For __RTE_ARM_LOAD_EXC, 'size' is known until code is running.
> So it cannot check 'size' in the compile time and BUILD_BUG_ON doesn't work here.
uint32_t size = sizeof(*(addr)) << 3 value will get in comple time as
_sizeof_ is preprocessor function.
So I think, BUILD_BUG_ON is fine.
> >
> >
> > > + if ((value & (mask)) cond expected_value) { \
> > > + __RTE_ARM_SEVL() \
> > > + do { \
> > > + __RTE_ARM_WFE() \
> > > + __RTE_ARM_LOAD_EXC((addr), value, memorder,
> > > + size) \
> >
> > if the address is the type of __int128_t. This logic will fail? Could you add
> > 128bit support too and remove the assert from __RTE_ARM_LOAD_EXC
> [Feifei] There is no 128bit case in library. And maybe there will be 128bits case, we can
> add 128 path here. Now there is assert check in __RTE_ARM_LOAD_EXC to check
> whether size is '16/32/64'.
API expects is only "addr" without any type so the application can use
128bit too.
Worst case for now we can fall back to __atomic_load_n() for size
128, we dont want
to break applications while using this API. Or add support for 128 in code.
> >
> >
> > > + } while ((value & (mask)) cond expected_value); \
> > > + } \
> > > +} while (0)
> > >
> > > #endif
> > >
> > > diff --git a/lib/eal/include/generic/rte_pause.h
> > > b/lib/eal/include/generic/rte_pause.h
> > > index 668ee4a184..d0c5b5a415 100644
> > > --- a/lib/eal/include/generic/rte_pause.h
> > > +++ b/lib/eal/include/generic/rte_pause.h
> > > @@ -111,6 +111,34 @@ rte_wait_until_equal_64(volatile uint64_t *addr,
> > uint64_t expected,
> > > while (__atomic_load_n(addr, memorder) != expected)
> > > rte_pause();
> > > }
> > > +
> > > +/*
> > > + * Wait until *addr breaks the condition, with a relaxed memory
> > > + * ordering model meaning the loads around this API can be reordered.
> > > + *
> > > + * @param addr
> > > + * A pointer to the memory location.
> > > + * @param mask
> > > + * A mask of value bits in interest.
> > > + * @param cond
> > > + * A symbol representing the condition.
> > > + * @param expected
> > > + * An expected value to be in the memory location.
> > > + * @param memorder
> > > + * Two different memory orders that can be specified:
> > > + * __ATOMIC_ACQUIRE and __ATOMIC_RELAXED. These map to
> > > + * C++11 memory orders with the same names, see the C++11 standard
> > > +or
> > > + * the GCC wiki on atomic synchronization for detailed definition.
> > > + */
> > > +#define rte_wait_event(addr, mask, cond, expected, memorder)
> > \
> > > +do { \
> > > + RTE_BUILD_BUG_ON(!__builtin_constant_p(memorder));
> > \
> > > + RTE_BUILD_BUG_ON(memorder != __ATOMIC_ACQUIRE &&
> > \
> > > + memorder != __ATOMIC_RELAXED); \
> > > + typeof(*(addr)) expected_value = (expected); \
> > > + while ((__atomic_load_n((addr), (memorder)) & (mask)) cond
> > expected_value) \
> > > + rte_pause(); \
> > > +} while (0)
> > > #endif
> > >
> > > #endif /* _RTE_PAUSE_H_ */
> > > --
> > > 2.25.1
> > >
next prev parent reply other threads:[~2021-10-28 7:51 UTC|newest]
Thread overview: 113+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-02 5:32 [dpdk-dev] [RFC PATCH v1 0/5] add new API for wait until scheme Feifei Wang
2021-09-02 5:32 ` [dpdk-dev] [RFC PATCH v1 1/5] eal: " Feifei Wang
2021-09-02 5:32 ` [dpdk-dev] [RFC PATCH v1 2/5] eal: use wait until scheme for read pflock Feifei Wang
2021-09-02 5:32 ` [dpdk-dev] [RFC PATCH v1 3/5] eal: use wait until scheme for mcslock Feifei Wang
2021-09-02 5:32 ` [dpdk-dev] [RFC PATCH v1 4/5] lib/bpf: use wait until scheme for Rx/Tx iteration Feifei Wang
2021-09-02 5:32 ` [dpdk-dev] [RFC PATCH v1 5/5] lib/distributor: use wait until scheme Feifei Wang
2021-09-02 15:22 ` [dpdk-dev] [RFC PATCH v1 0/5] add new API for " Stephen Hemminger
2021-09-03 7:02 ` [dpdk-dev] 回复: " Feifei Wang
2021-09-23 9:58 ` [dpdk-dev] [RFC PATCH v2 0/5] add new definitions for wait scheme Feifei Wang
2021-09-23 9:58 ` [dpdk-dev] [RFC PATCH v2 1/5] eal: " Feifei Wang
2021-09-23 9:58 ` [dpdk-dev] [RFC PATCH v2 2/5] eal: use wait event for read pflock Feifei Wang
2021-09-23 9:59 ` [dpdk-dev] [RFC PATCH v2 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-09-23 9:59 ` [dpdk-dev] [RFC PATCH v2 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-09-24 18:07 ` Ananyev, Konstantin
2021-09-26 2:19 ` [dpdk-dev] 回复: " Feifei Wang
2021-09-23 9:59 ` [dpdk-dev] [RFC PATCH v2 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-09-26 6:32 ` [dpdk-dev] [RFC PATCH v3 0/5] add new definitions for wait scheme Feifei Wang
2021-09-26 6:32 ` [dpdk-dev] [RFC PATCH v3 1/5] eal: " Feifei Wang
2021-10-07 16:18 ` Ananyev, Konstantin
2021-10-12 8:09 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-13 15:03 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-13 17:00 ` Stephen Hemminger
2021-10-14 3:14 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-14 3:08 ` Feifei Wang
2021-09-26 6:32 ` [dpdk-dev] [RFC PATCH v3 2/5] eal: use wait event for read pflock Feifei Wang
2021-09-26 6:33 ` [dpdk-dev] [RFC PATCH v3 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-09-26 6:33 ` [dpdk-dev] [RFC PATCH v3 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-10-07 15:50 ` Ananyev, Konstantin
2021-10-07 17:40 ` Ananyev, Konstantin
2021-10-20 6:20 ` [dpdk-dev] 回复: " Feifei Wang
2021-09-26 6:33 ` [dpdk-dev] [RFC PATCH v3 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 0/5] add new definitions for wait scheme Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 1/5] eal: " Feifei Wang
2021-10-21 16:24 ` Ananyev, Konstantin
2021-10-25 9:20 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-25 14:28 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-26 1:08 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-22 0:10 ` [dpdk-dev] " Jerin Jacob
2021-10-25 9:30 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-25 9:43 ` [dpdk-dev] " Jerin Jacob
2021-10-26 1:11 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 2/5] eal: use wait event for read pflock Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-10-20 8:45 ` [dpdk-dev] [PATCH v4 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-10-26 8:01 ` [dpdk-dev] [PATCH v5 0/5] add new definitions for wait scheme Feifei Wang
2021-10-26 8:02 ` [dpdk-dev] [PATCH v5 1/5] eal: " Feifei Wang
2021-10-26 8:08 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-26 9:46 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-26 9:59 ` Ananyev, Konstantin
2021-10-27 6:56 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-26 8:02 ` [dpdk-dev] [PATCH v5 2/5] eal: use wait event for read pflock Feifei Wang
2021-10-26 8:02 ` [dpdk-dev] [PATCH v5 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-10-26 8:02 ` [dpdk-dev] [PATCH v5 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-10-26 8:18 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-26 9:43 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-26 12:56 ` Ananyev, Konstantin
2021-10-27 7:04 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-27 7:31 ` Feifei Wang
2021-10-27 14:47 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-28 6:24 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-26 8:02 ` [dpdk-dev] [PATCH v5 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-10-27 8:10 ` [dpdk-dev] [PATCH v6 0/4] add new definitions for wait scheme Feifei Wang
2021-10-27 8:10 ` [dpdk-dev] [PATCH v6 1/4] eal: " Feifei Wang
2021-10-27 8:10 ` [dpdk-dev] [PATCH v6 2/4] eal: use wait event for read pflock Feifei Wang
2021-10-27 8:10 ` [dpdk-dev] [PATCH v6 3/4] eal: use wait event scheme for mcslock Feifei Wang
2021-10-27 11:16 ` Mattias Rönnblom
2021-10-28 6:32 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-27 8:10 ` [dpdk-dev] [PATCH v6 4/4] lib/distributor: use wait event scheme Feifei Wang
2021-10-27 10:57 ` [dpdk-dev] [PATCH v6 0/4] add new definitions for wait scheme Jerin Jacob
2021-10-28 6:33 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 0/5] " Feifei Wang
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 1/5] eal: " Feifei Wang
2021-10-28 7:15 ` Jerin Jacob
2021-10-28 7:40 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-28 7:51 ` Jerin Jacob [this message]
2021-10-28 9:27 ` Feifei Wang
2021-10-28 13:14 ` [dpdk-dev] " Ananyev, Konstantin
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 2/5] eal: use wait event for read pflock Feifei Wang
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-10-28 7:02 ` Jerin Jacob
2021-10-28 7:14 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-10-28 13:15 ` Ananyev, Konstantin
2021-10-28 6:56 ` [dpdk-dev] [PATCH v7 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 0/5] add new definitions for wait scheme Feifei Wang
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 1/5] eal: " Feifei Wang
2021-10-29 13:54 ` Jerin Jacob
2021-10-31 8:38 ` David Marchand
2021-11-01 2:29 ` [dpdk-dev] 回复: " Feifei Wang
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 2/5] eal: use wait event for read pflock Feifei Wang
2021-10-29 13:55 ` Jerin Jacob
2021-10-31 8:37 ` David Marchand
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 3/5] eal: use wait event scheme for mcslock Feifei Wang
2021-10-29 13:55 ` Jerin Jacob
2021-10-31 8:37 ` David Marchand
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 4/5] lib/bpf: use wait event scheme for Rx/Tx iteration Feifei Wang
2021-10-31 8:37 ` David Marchand
2021-10-29 8:20 ` [dpdk-dev] [PATCH v8 5/5] lib/distributor: use wait event scheme Feifei Wang
2021-10-29 13:58 ` Jerin Jacob
2021-10-31 8:38 ` David Marchand
2021-11-01 12:44 ` David Hunt
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 0/5] add new helper for wait scheme Feifei Wang
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 1/5] eal: add a new generic " Feifei Wang
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 2/5] pflock: use wait until scheme for read pflock Feifei Wang
2021-11-03 14:46 ` David Marchand
2021-11-04 1:24 ` [dpdk-dev] 回复: " Feifei Wang
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 3/5] mcslock: use wait until scheme for mcslock Feifei Wang
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 4/5] bpf: use wait until scheme for Rx/Tx iteration Feifei Wang
2021-11-01 6:00 ` [dpdk-dev] [PATCH v9 5/5] distributor: use wait until scheme Feifei Wang
2021-11-01 16:05 ` Pattan, Reshma
2021-11-02 2:00 ` [dpdk-dev] 回复: " Feifei Wang
2021-11-03 14:55 ` [dpdk-dev] [PATCH v9 0/5] add new helper for wait scheme David Marchand
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