From nobody Mon Aug 3 15:23:05 2026 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4hDL622tMwz6mMP8 for ; Mon, 03 Aug 2026 15:23:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "YR1" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hDL615HgRz3G35 for ; Mon, 03 Aug 2026 15:23:05 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785770585; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=idZuTWzwmyfdUjGkdmXLGS9J9yHLWvdFYIqSUqUtM1Q=; b=ke+JuFZ98SFqwEbsgaRjvjGEnkwPp46XwkbLW0Kc4kWa3TLWJ1flvhdSAvOENyc6y1NTeq dANrBncizjTmNO/LU95bBJ6Y7A88Lh910fmgrUtS/fpWz9V7JU25jsdFwZKcZ/Yw1b4zMu P4KbDMvemabsCbM/iF8dJG7OO33H/ti/WoWpk3f59+e2OE6+5sQsX/9lfk4dYWY90Am7L6 E/sSd5Z9hsxqAXScAQn+mev9ZvFT42cyy/SxyF6Bxf7nlAl4EpsEgWt+dVqwKAxraYyfIk LC9BZgt/D9tkULpFwSkJi7QKraErtCN5+U5IxBxU/EsJOvKejoAko/sj/uEXig== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1785770585; a=rsa-sha256; cv=none; b=ZZLxQAzi+Rf3AxZz4aUb0d5VSGTwhL5KujgWwCRAaaRPiTIlrgWX95zJOFHzs/z9AU/RO+ 2svBOxFflhR2XYmzYma06o+Cvy8xloVQ8kfUKXAqM7VuHr5d2J+Izg+e9KG12xEPizdA0i zV511nv88ohYxzK4Fc0+hljJ3lTBN+PbAo3hB+OX4siy6v7R0PGPoG807gkNtf1tP/7MHB 6L2gkoY8CYcQGYJB0jhUk5KOqt/ug+BM814+rsx2UBOKd9IMq6Ge9NUosYkqy6Yq4M3sCH D8WlKU9iPJewrXTTATmVXs7hyFM2bTsbTAGdc2t0rlNPqwvc98Vnofm9Gtc5Rw== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1785770585; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=idZuTWzwmyfdUjGkdmXLGS9J9yHLWvdFYIqSUqUtM1Q=; b=T3LgkELxCi7ftcJtzznA6zILO1QgOtcGX5X37OHroxNW8Q6A1EMdj1HOI3UbWF0o13hf6H rZ1k6Mf+41pUYGfp/Fvko0hbrMXcl5h36VRQMc5ztCADLkj23fsD/9/5j8PkKwuCltccCH LnJIdkwflr1HrS38c/o2PuGzW+/7p8HDoRpvicU6whVTAN41eaApXGzcYe4wZw1tiWXz+7 bMbxinKLvTv9DZdV+UwKAr4pZciHbNM8EYNN8if0l9k2mpC6cWGeQKYGev6n8tnfIhKaX6 LGjLaQEDEP2hYvMiR0ZAbYoZwWqb2DXhBO/QofyOitNuny0Riix6gVZ2ge2txw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4hDL613krvz15bT for ; Mon, 03 Aug 2026 15:23:05 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 3b34b by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Mon, 03 Aug 2026 15:23:05 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: fb63bc67483e - main - atomic: Implement atomic_{set,clear}_8 in _atomic_subword.h List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: fb63bc67483ee52245d6161150702974da3d001c Auto-Submitted: auto-generated Date: Mon, 03 Aug 2026 15:23:05 +0000 Message-Id: <6a70b259.3b34b.2d962251@gitrepo.freebsd.org> The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=fb63bc67483ee52245d6161150702974da3d001c commit fb63bc67483ee52245d6161150702974da3d001c Author: Mark Johnston AuthorDate: 2026-08-03 14:02:33 +0000 Commit: Mark Johnston CommitDate: 2026-08-03 15:22:13 +0000 atomic: Implement atomic_{set,clear}_8 in _atomic_subword.h Reimplement atomic_{set,clear}_16 using atomic_set_32. Remove emulation of these operations from vm_page.c. Reviewed by: alc, kib MFC after: 2 weeks Differential Revision: https://reviews.freebsd.org/D58580 --- sys/sys/_atomic_subword.h | 54 +++++++++++++++++++++++---------- sys/vm/vm_page.c | 76 ++++++----------------------------------------- 2 files changed, 48 insertions(+), 82 deletions(-) diff --git a/sys/sys/_atomic_subword.h b/sys/sys/_atomic_subword.h index 284e2bfa340f..907fef0bb193 100644 --- a/sys/sys/_atomic_subword.h +++ b/sys/sys/_atomic_subword.h @@ -201,21 +201,42 @@ atomic_load_acq_16(const volatile uint16_t *p) } #endif -#undef _ATOMIC_WORD_ALIGNED -#undef _ATOMIC_BYTE_SHIFT -#undef _ATOMIC_HWORD_SHIFT +#ifndef atomic_set_8 +static __inline void +atomic_set_8(volatile uint8_t *p, uint8_t bit) +{ + uint32_t *addr; + int shift; + + addr = _ATOMIC_WORD_ALIGNED(p); + shift = _ATOMIC_BYTE_SHIFT(p); + atomic_set_32(addr, (uint32_t)bit << shift); +} +#endif #ifndef atomic_set_16 static __inline void atomic_set_16(volatile uint16_t *p, uint16_t bit) { - uint16_t v; + uint32_t *addr; + int shift; + + addr = _ATOMIC_WORD_ALIGNED(p); + shift = _ATOMIC_HWORD_SHIFT(p); + atomic_set_32(addr, (uint32_t)bit << shift); +} +#endif + +#ifndef atomic_clear_8 +static __inline void +atomic_clear_8(volatile uint8_t *p, uint8_t bit) +{ + uint32_t *addr; + int shift; - v = atomic_load_16(p); - for (;;) { - if (atomic_fcmpset_16(p, &v, v | bit)) - break; - } + addr = _ATOMIC_WORD_ALIGNED(p); + shift = _ATOMIC_BYTE_SHIFT(p); + atomic_clear_32(addr, (uint32_t)bit << shift); } #endif @@ -223,14 +244,17 @@ atomic_set_16(volatile uint16_t *p, uint16_t bit) static __inline void atomic_clear_16(volatile uint16_t *p, uint16_t bit) { - uint16_t v; + uint32_t *addr; + int shift; - v = atomic_load_16(p); - for (;;) { - if (atomic_fcmpset_16(p, &v, v & ~bit)) - break; - } + addr = _ATOMIC_WORD_ALIGNED(p); + shift = _ATOMIC_HWORD_SHIFT(p); + atomic_clear_32(addr, (uint32_t)bit << shift); } #endif +#undef _ATOMIC_WORD_ALIGNED +#undef _ATOMIC_BYTE_SHIFT +#undef _ATOMIC_HWORD_SHIFT + #endif /* _SYS__ATOMIC_SUBWORD_H_ */ diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c index 130d084815f6..98d0472c8487 100644 --- a/sys/vm/vm_page.c +++ b/sys/vm/vm_page.c @@ -5378,67 +5378,33 @@ vm_page_bits(int base, int size) void vm_page_bits_set(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t set) { - #if PAGE_SIZE == 32768 atomic_set_64((uint64_t *)bits, set); #elif PAGE_SIZE == 16384 atomic_set_32((uint32_t *)bits, set); -#elif (PAGE_SIZE == 8192) && defined(atomic_set_16) +#elif PAGE_SIZE == 8192 atomic_set_16((uint16_t *)bits, set); -#elif (PAGE_SIZE == 4096) && defined(atomic_set_8) +#elif PAGE_SIZE == 4096 atomic_set_8((uint8_t *)bits, set); -#else /* PAGE_SIZE <= 8192 */ - uintptr_t addr; - int shift; - - addr = (uintptr_t)bits; - /* - * Use a trick to perform a 32-bit atomic on the - * containing aligned word, to not depend on the existence - * of atomic_{set, clear}_{8, 16}. - */ - shift = addr & (sizeof(uint32_t) - 1); -#if BYTE_ORDER == BIG_ENDIAN - shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; #else - shift *= NBBY; +#error unhandled page size #endif - addr &= ~(sizeof(uint32_t) - 1); - atomic_set_32((uint32_t *)addr, set << shift); -#endif /* PAGE_SIZE */ } static inline void vm_page_bits_clear(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t clear) { - #if PAGE_SIZE == 32768 atomic_clear_64((uint64_t *)bits, clear); #elif PAGE_SIZE == 16384 atomic_clear_32((uint32_t *)bits, clear); -#elif (PAGE_SIZE == 8192) && defined(atomic_clear_16) +#elif PAGE_SIZE == 8192 atomic_clear_16((uint16_t *)bits, clear); -#elif (PAGE_SIZE == 4096) && defined(atomic_clear_8) +#elif PAGE_SIZE == 4096 atomic_clear_8((uint8_t *)bits, clear); -#else /* PAGE_SIZE <= 8192 */ - uintptr_t addr; - int shift; - - addr = (uintptr_t)bits; - /* - * Use a trick to perform a 32-bit atomic on the - * containing aligned word, to not depend on the existence - * of atomic_{set, clear}_{8, 16}. - */ - shift = addr & (sizeof(uint32_t) - 1); -#if BYTE_ORDER == BIG_ENDIAN - shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; #else - shift *= NBBY; +#error unhandled page size #endif - addr &= ~(sizeof(uint32_t) - 1); - atomic_clear_32((uint32_t *)addr, clear << shift); -#endif /* PAGE_SIZE */ } static inline vm_page_bits_t @@ -5456,45 +5422,21 @@ vm_page_bits_swap(vm_page_t m, vm_page_bits_t *bits, vm_page_bits_t newbits) old = *bits; while (atomic_fcmpset_32(bits, &old, newbits) == 0); return (old); -#elif (PAGE_SIZE == 8192) && defined(atomic_fcmpset_16) +#elif PAGE_SIZE == 8192 uint16_t old; old = *bits; while (atomic_fcmpset_16(bits, &old, newbits) == 0); return (old); -#elif (PAGE_SIZE == 4096) && defined(atomic_fcmpset_8) +#elif PAGE_SIZE == 4096 uint8_t old; old = *bits; while (atomic_fcmpset_8(bits, &old, newbits) == 0); return (old); -#else /* PAGE_SIZE <= 4096*/ - uintptr_t addr; - uint32_t old, new, mask; - int shift; - - addr = (uintptr_t)bits; - /* - * Use a trick to perform a 32-bit atomic on the - * containing aligned word, to not depend on the existence - * of atomic_{set, swap, clear}_{8, 16}. - */ - shift = addr & (sizeof(uint32_t) - 1); -#if BYTE_ORDER == BIG_ENDIAN - shift = (sizeof(uint32_t) - sizeof(vm_page_bits_t) - shift) * NBBY; #else - shift *= NBBY; +#error unhandled page size #endif - addr &= ~(sizeof(uint32_t) - 1); - mask = VM_PAGE_BITS_ALL << shift; - - old = *bits; - do { - new = old & ~mask; - new |= newbits << shift; - } while (atomic_fcmpset_32((uint32_t *)addr, &old, new) == 0); - return (old >> shift); -#endif /* PAGE_SIZE */ } /*