DPDK patches and discussions
 help / color / mirror / Atom feed
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 <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 12:45:49 +0530
Message-ID: <CALBAE1N_XGvTDuCGOLOesM9s018CvAJ2igRM0P4AhKiZH3iBRg@mail.gmail.com> (raw)
In-Reply-To: <20211028065640.139655-2-feifei.wang2@arm.com>

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


> +
> +       __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

>
> -       /*
> -        * 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

> +       typeof(*(addr)) expected_value = (expected);                      \
> +       typeof(*(addr)) value = 0;

Why zero assignment
                                        \
> +       __RTE_ARM_LOAD_EXC((addr), value, memorder, size)                 \

Assert is not good in the library, Why not RTE_BUILD_BUG_ON here


> +       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


> +               } 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
>

  reply	other threads:[~2021-10-28  7:16 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 [this message]
2021-10-28  7:40       ` [dpdk-dev] 回复: " Feifei Wang
2021-10-28  7:51         ` [dpdk-dev] " Jerin Jacob
2021-10-28  9:27           ` [dpdk-dev] 回复: " 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

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=CALBAE1N_XGvTDuCGOLOesM9s018CvAJ2igRM0P4AhKiZH3iBRg@mail.gmail.com \
    --to=jerinjacobk@gmail.com \
    --cc=david.marchand@redhat.com \
    --cc=dev@dpdk.org \
    --cc=feifei.wang2@arm.com \
    --cc=konstantin.ananyev@intel.com \
    --cc=mattias.ronnblom@ericsson.com \
    --cc=nd@arm.com \
    --cc=ruifeng.wang@arm.com \
    --cc=stephen@networkplumber.org \
    --cc=thomas@monjalon.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

DPDK patches and discussions

This inbox may be cloned and mirrored by anyone:

	git clone --mirror http://inbox.dpdk.org/dev/0 dev/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 dev dev/ http://inbox.dpdk.org/dev \
		dev@dpdk.org
	public-inbox-index dev

Example config snippet for mirrors.
Newsgroup available over NNTP:
	nntp://inbox.dpdk.org/inbox.dpdk.dev


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git