From nobody Sat Oct 4 00:31:35 2025 Received: from m16.mail.163.com (m16.mail.163.com [220.197.31.3]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DAD1A2EE619; Fri, 22 Aug 2025 16:03:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=220.197.31.3 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755878593; cv=none; b=VTTDVi2ijRVJRoaEpkZaSgVIrz6YPZHbcmc/Zf7Tq64LijACB7utHPp0RDKg0qQyNKpjl0gvIFsk+zxPzuM8Mvr5iED+tnxfgteLfF7wHwPOo9+kThOPfxwy01ARw+jmlMC4ECinAjpU/zWMWbVzko6Ir9Gx5sEdWH9EDQUERtM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1755878593; c=relaxed/simple; bh=nr3Ae750UOQEzP08Bo69gzr0P07LB02KeF46y/lUPf0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ZyPWEDkiAc1+oI4Wajp42OTFRFiYyvSzjppovzFs07SjEbV2kMZRRoFPvOKxVXtQZQgH/8+AoU3mBZBdQJR3T33rbweM1IwB2wfp1mlpkOkFN7BlQQwh7YyVRShPlGXGf/ITWAnAWOhNH8FqrFBZOIkElPskyKSdglnhxyYYWi0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com; spf=pass smtp.mailfrom=163.com; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b=WbftlpqF; arc=none smtp.client-ip=220.197.31.3 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=163.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=163.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=163.com header.i=@163.com header.b="WbftlpqF" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=163.com; s=s110527; h=From:To:Subject:Date:Message-Id:MIME-Version; bh=pj MLZ/AH8cr5pUt0a3faTC4a4e2/NRtUHfVcVQQjNps=; b=WbftlpqFe34I90sWWf 9oIKlki2wlIN1mGtVu2QYVe8uMdOgnDFnWPKe2qg4Zz/FVAmRIbc4rzmNi1A4bhQ jWKOLv0tm6E6Ba47Af5/0VDQ4YuKXKhYSullyrsl+6TuNF6SUyQrvKq2NwkZ5rOh MSHNeNbmIKPP7C2WHxX1W5Wlk= Received: from localhost.localdomain (unknown []) by gzsmtp4 (Coremail) with SMTP id PygvCgBnxDaplKho3jnHAA--.18200S9; Sat, 23 Aug 2025 00:02:54 +0800 (CST) From: Hans Zhang <18255117159@163.com> To: bhelgaas@google.com, helgaas@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Hans Zhang <18255117159@163.com> Subject: [PATCH v2 7/7] PCI/DPC: Replace msleep(10) with usleep_range() for precise RP busy checking Date: Fri, 22 Aug 2025 23:59:08 +0800 Message-Id: <20250822155908.625553-8-18255117159@163.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20250822155908.625553-1-18255117159@163.com> References: <20250822155908.625553-1-18255117159@163.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CM-TRANSID: PygvCgBnxDaplKho3jnHAA--.18200S9 X-Coremail-Antispam: 1Uf129KBjvJXoW7KFyxZFWfAr17Zr47Ar45trb_yoW8GF47pF WfG345A3WrXFyYkan8Xas5u3Z8tFnFkFyUGr97W3Z3ua4Ykw1UCF10ka4DXw1FqrZ5Xry5 XF1ktrn8X3WYvw7anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDUYxBIdaVFxhVjvjDU0xZFpf9x0pR8wIDUUUUU= X-CM-SenderInfo: rpryjkyvrrlimvzbiqqrwthudrp/1tbiOh6xo2iokEFcmwAAsg Content-Type: text/plain; charset="utf-8" The msleep(10) in dpc_wait_rp_inactive() may sleep longer than intended due to timer granularity, which can cause unnecessary delays in downstream port containment recovery. Replace it with usleep_range() for a more precise delay of approximately 10ms. Signed-off-by: Hans Zhang <18255117159@163.com> --- drivers/pci/pcie/dpc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/drivers/pci/pcie/dpc.c b/drivers/pci/pcie/dpc.c index fc18349614d7..ff0884d669b7 100644 --- a/drivers/pci/pcie/dpc.c +++ b/drivers/pci/pcie/dpc.c @@ -21,6 +21,8 @@ #define PCI_EXP_DPC_CTL_EN_MASK (PCI_EXP_DPC_CTL_EN_FATAL | \ PCI_EXP_DPC_CTL_EN_NONFATAL) =20 +#define PCIE_EXP_DPC_BUSY_CHECK_US 10000 + static const char * const rp_pio_error_string[] =3D { "Configuration Request received UR Completion", /* Bit Position 0 */ "Configuration Request received CA Completion", /* Bit Position 1 */ @@ -135,7 +137,8 @@ static int dpc_wait_rp_inactive(struct pci_dev *pdev) pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); while (status & PCI_EXP_DPC_RP_BUSY && !time_after(jiffies, timeout)) { - msleep(10); + usleep_range(PCIE_EXP_DPC_BUSY_CHECK_US, + PCIE_EXP_DPC_BUSY_CHECK_US + 100); pci_read_config_word(pdev, cap + PCI_EXP_DPC_STATUS, &status); } if (status & PCI_EXP_DPC_RP_BUSY) { --=20 2.25.1