From nobody Thu Oct 22 17:31:49 2026 X-Original-To: dev-commits-src-all@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 4j9Y9f2hWBz6xPBm for ; Thu, 22 Oct 2026 17:31:50 +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) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id 4j9Y9f01B5z3Gjq for ; Thu, 22 Oct 2026 17:31:50 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1792690310; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=UeFMxA9yggTSKZ1EnppW2ASy8GmG7zRz/VccJVwnT+I=; b=X6lEZMzzbwEeP/wJvXfh1vq60cY0LXn5kX+WGj7zzmcfPBvQN07OTH8cg8W7/0NpZ1WXCo onuHYiV6LDOvI7qHb1Rl/1D+8FeX4pQLQTR3Hv77otSi0F/6JDleCwQPA6H0tc6FCqYqVL L+NrHk8g9mIn1unbjulZIySneAfVUUCwnuj4OEgpJHCtfT7lmdLOaLQmevMrKDuplYAeYY pL43w3jSV6f4DtxtaM0lL81ABBq4f/Qyzl5LDuesUYB31f8Ytkn7zO9xvk8Dp73dvxZFSG n6/jRv3tpIPTIMtccgj2BwdOMz+G8Trbq0rlHE1XAu3I2NNHEf6EmkxvUxVuzA== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1792690310; b=h6IrOP9/luG4INf5AsriI8qFOJveKd/aujbqwAN9LSu0w47OntuO/ON4tA+UHwKi0BlSMi 2hF+BuZQjOyq3vGhIMbI9zWgrgwkuD0aq2ux5K2j2r5fz9sU+g1yOaU/mPHDsSbt5uk4Se TZ0nN/z8+B2Q4ooANy2S1J+PDTTZbAQFhA47xuCiT0cL0UfExkashQXOcdJ/3RuuESqe/r 4m59s9jQ1fG0fRznkQmbf4FeSZUSvL3Kdn0bZYHiKPMP8mnmiBHMH6ELLZ6xq9/sm/4yOL NTki21g+1dw09ewnGUCDDAHxWZRw7iadOcvXgLzwc7IfyZPPwHFwt7UhywL5ww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1792690310; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=UeFMxA9yggTSKZ1EnppW2ASy8GmG7zRz/VccJVwnT+I=; b=XtLL0CJyVicTLrkBW+V82OSepMS9sCl3K8C/5/zwGLAg8R5X/8QyISeX30thzz/z19tDyJ +ZSMDFf6pMWiUUVKYNXXFBGOt7dM9S+BMcAiM2GHU90gPEpve3YwoykQLzFrB6Yc1ar1KO OgADiUfMu1VZBSLyTFJ2MRDQoYvM+XBC7mctogWO+pvSZolz8hKIM23UQck2p1QaPcv+GJ sRmOOqMc8iar8ZKVGtAMdkfyPyl/+G3UH7MXnhZsJ4EqEOWI9qfATmSY/flivX0xM5as3G jM8+PSFbJvNED3P1CRHShyqqe9j943AtmWbyefE+W3R9pfqTCW6T4qVOzL3rMQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4j9Y9d6d7yzrnN for ; Thu, 22 Oct 2026 17:31:49 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 3ee80 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Thu, 22 Oct 2026 17:31:49 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Cc: Benjamin Jacobs From: Mark Johnston Subject: git: a1328d049522 - stable/15 - dtrace/arm: Fix and de-pessimize dtrace_copy List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: Commit messages for all branches of the src repository 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/stable/15 X-Git-Reftype: branch X-Git-Commit: a1328d049522177ea9d8103de8d717bd4fe2538c Auto-Submitted: auto-generated Date: Thu, 22 Oct 2026 17:31:49 +0000 Message-Id: <6ada4885.3ee80.4d95a165@gitrepo.freebsd.org> The branch stable/15 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=a1328d049522177ea9d8103de8d717bd4fe2538c commit a1328d049522177ea9d8103de8d717bd4fe2538c Author: Benjamin Jacobs AuthorDate: 2026-09-03 13:52:21 +0000 Commit: Mark Johnston CommitDate: 2026-10-22 15:45:40 +0000 dtrace/arm: Fix and de-pessimize dtrace_copy Use an unprivileged load to access user memory from dtrace_copy, which is running in SVC mode. Abort the loop if the load is trapped, as it is useless, hence wasteful, to keep faulting on successive addresses. I believe that this de-pessimization should also be done on aarch64 and riscv. PR: 298064 MFC after: 1 month Reviewed by: markj Differential Revision: https://reviews.freebsd.org/D59280 (cherry picked from commit c874d312e78fc60e6731a043fc45b47165618370) --- sys/cddl/dev/dtrace/arm/dtrace_asm.S | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/sys/cddl/dev/dtrace/arm/dtrace_asm.S b/sys/cddl/dev/dtrace/arm/dtrace_asm.S index b0eba6f1ed9f..d4730384b581 100644 --- a/sys/cddl/dev/dtrace/arm/dtrace_asm.S +++ b/sys/cddl/dev/dtrace/arm/dtrace_asm.S @@ -130,13 +130,14 @@ dtrace_copy(uintptr_t uaddr, uintptr_t kaddr, size_t size) ENTRY(dtrace_copy) stmfd sp!, {r4-r5} /* stack is 8 byte aligned */ teq r2, #0x00000000 - mov r5, #0x00000000 beq 2f -1: ldrb r4, [r0], #0x0001 - add r5, r5, #0x00000001 - strb r4, [r1], #0x0001 - teqne r5, r2 +1: mov r4, r0 + ldrbt r3, [r0], #1 + teq r0, r4 /* Check if the load was trapped */ + beq 2f /* Yes, quit now */ + strb r3, [r1], #1 + subs r2, r2, #1 bne 1b 2: ldmfd sp!, {r4-r5} /* stack is 8 byte aligned */