Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751180AbaJWEpQ (ORCPT ); Thu, 23 Oct 2014 00:45:16 -0400 Received: from szxga02-in.huawei.com ([119.145.14.65]:54418 "EHLO szxga02-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750730AbaJWEpN (ORCPT ); Thu, 23 Oct 2014 00:45:13 -0400 Message-ID: <544887A8.5090708@huawei.com> Date: Thu, 23 Oct 2014 12:44:24 +0800 From: Yijing Wang User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:24.0) Gecko/20100101 Thunderbird/24.0.1 MIME-Version: 1.0 To: Bjorn Helgaas CC: , , Xinwei Hu , Wuyun , , Russell King , , , , , Arnd Bergmann , Thomas Gleixner , "Konrad Rzeszutek Wilk" , , Joerg Roedel , , , Benjamin Herrenschmidt , , , Sebastian Ott , "Tony Luck" , , "David S. Miller" , , Chris Metcalf , Ralf Baechle , Lucas Stach , David Vrabel , "Sergei Shtylyov" , Michael Ellerman , Thierry Reding , "Thomas Petazzoni" , Liviu Dudau Subject: Re: [PATCH v3 02/27] x86/xen/MSI: Eliminate arch_msix_mask_irq() and arch_msi_mask_irq() References: <1413342435-7876-1-git-send-email-wangyijing@huawei.com> <1413342435-7876-3-git-send-email-wangyijing@huawei.com> <20141023042535.GA11770@google.com> In-Reply-To: <20141023042535.GA11770@google.com> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.177.27.212] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014/10/23 12:25, Bjorn Helgaas wrote: > On Wed, Oct 15, 2014 at 11:06:50AM +0800, Yijing Wang wrote: >> Commit 0e4ccb1505a9 ("PCI: Add x86_msi.msi_mask_irq() and msix_mask_irq()") >> introduced two __weak arch functions arch_msix_mask_irq() and >> arch_msi_mask_irq() to work around a bug when running xen in x86. >> These two functions made msi code more complex. This patch reverts >> the commit and introduces a global flag to control msi mask action to >> avoid the bug. The patch is also preparation for using MSI chip framework >> instead of weak arch MSI functions in all platforms. Keep default_msi_mask_irq() >> and default_msix_mask_irq() in linux/msi.h to make s390 MSI code compile >> happy, they will be removed in the later patch. > > This patch is basically a revert of 0e4ccb1505a9 intermingled with the > addition of the new pci_msi_ignore_mask technique. > > Can you please split this into two patches: > > - Add the pci_msi_ignore_mask stuff (alongside the existing way) > - Revert 0e4ccb1505a9 > > I think that will make it easier to see what's going on. OK, I will do it, thanks. Thanks! Yijing. > >> Signed-off-by: Yijing Wang >> CC: David Vrabel >> CC: Konrad Rzeszutek Wilk >> --- >> Hi David and Konrad, >> I dropped the Acked-by and tested-by, because this version has a >> lot changes compared to last. So, I guess you may want to check it again. >> --- >> arch/x86/include/asm/x86_init.h | 3 --- >> arch/x86/kernel/x86_init.c | 10 ---------- >> arch/x86/pci/xen.c | 14 ++------------ >> drivers/pci/msi.c | 29 ++++++++++++----------------- >> include/linux/msi.h | 8 ++++++-- >> 5 files changed, 20 insertions(+), 44 deletions(-) >> >> diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h >> index e45e4da..f58a9c7 100644 >> --- a/arch/x86/include/asm/x86_init.h >> +++ b/arch/x86/include/asm/x86_init.h >> @@ -172,7 +172,6 @@ struct x86_platform_ops { >> >> struct pci_dev; >> struct msi_msg; >> -struct msi_desc; >> >> struct x86_msi_ops { >> int (*setup_msi_irqs)(struct pci_dev *dev, int nvec, int type); >> @@ -183,8 +182,6 @@ struct x86_msi_ops { >> void (*teardown_msi_irqs)(struct pci_dev *dev); >> void (*restore_msi_irqs)(struct pci_dev *dev); >> int (*setup_hpet_msi)(unsigned int irq, unsigned int id); >> - u32 (*msi_mask_irq)(struct msi_desc *desc, u32 mask, u32 flag); >> - u32 (*msix_mask_irq)(struct msi_desc *desc, u32 flag); >> }; >> >> struct IO_APIC_route_entry; >> diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c >> index e48b674..234b072 100644 >> --- a/arch/x86/kernel/x86_init.c >> +++ b/arch/x86/kernel/x86_init.c >> @@ -116,8 +116,6 @@ struct x86_msi_ops x86_msi = { >> .teardown_msi_irqs = default_teardown_msi_irqs, >> .restore_msi_irqs = default_restore_msi_irqs, >> .setup_hpet_msi = default_setup_hpet_msi, >> - .msi_mask_irq = default_msi_mask_irq, >> - .msix_mask_irq = default_msix_mask_irq, >> }; >> >> /* MSI arch specific hooks */ >> @@ -140,14 +138,6 @@ void arch_restore_msi_irqs(struct pci_dev *dev) >> { >> x86_msi.restore_msi_irqs(dev); >> } >> -u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> -{ >> - return x86_msi.msi_mask_irq(desc, mask, flag); >> -} >> -u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag) >> -{ >> - return x86_msi.msix_mask_irq(desc, flag); >> -} >> #endif >> >> struct x86_io_apic_ops x86_io_apic_ops = { >> diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c >> index 093f5f4..e5b8b78 100644 >> --- a/arch/x86/pci/xen.c >> +++ b/arch/x86/pci/xen.c >> @@ -394,14 +394,6 @@ static void xen_teardown_msi_irq(unsigned int irq) >> { >> xen_destroy_irq(irq); >> } >> -static u32 xen_nop_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> -{ >> - return 0; >> -} >> -static u32 xen_nop_msix_mask_irq(struct msi_desc *desc, u32 flag) >> -{ >> - return 0; >> -} >> #endif >> >> int __init pci_xen_init(void) >> @@ -425,8 +417,7 @@ int __init pci_xen_init(void) >> x86_msi.setup_msi_irqs = xen_setup_msi_irqs; >> x86_msi.teardown_msi_irq = xen_teardown_msi_irq; >> x86_msi.teardown_msi_irqs = xen_teardown_msi_irqs; >> - x86_msi.msi_mask_irq = xen_nop_msi_mask_irq; >> - x86_msi.msix_mask_irq = xen_nop_msix_mask_irq; >> + pci_msi_ignore_mask = 1; >> #endif >> return 0; >> } >> @@ -506,8 +497,7 @@ int __init pci_xen_initial_domain(void) >> x86_msi.setup_msi_irqs = xen_initdom_setup_msi_irqs; >> x86_msi.teardown_msi_irq = xen_teardown_msi_irq; >> x86_msi.restore_msi_irqs = xen_initdom_restore_msi_irqs; >> - x86_msi.msi_mask_irq = xen_nop_msi_mask_irq; >> - x86_msi.msix_mask_irq = xen_nop_msix_mask_irq; >> + pci_msi_ignore_mask = 1; >> #endif >> xen_setup_acpi_sci(); >> __acpi_register_gsi = acpi_register_gsi_xen; >> diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c >> index ecb92a5..22e413c 100644 >> --- a/drivers/pci/msi.c >> +++ b/drivers/pci/msi.c >> @@ -23,6 +23,7 @@ >> #include "pci.h" >> >> static int pci_msi_enable = 1; >> +int pci_msi_ignore_mask; >> >> #define msix_table_size(flags) ((flags & PCI_MSIX_FLAGS_QSIZE) + 1) >> >> @@ -162,11 +163,11 @@ static inline __attribute_const__ u32 msi_mask(unsigned x) >> * reliably as devices without an INTx disable bit will then generate a >> * level IRQ which will never be cleared. >> */ >> -u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> +u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> { >> u32 mask_bits = desc->masked; >> >> - if (!desc->msi_attrib.maskbit) >> + if (pci_msi_ignore_mask || !desc->msi_attrib.maskbit) >> return 0; >> >> mask_bits &= ~mask; >> @@ -176,14 +177,9 @@ u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> return mask_bits; >> } >> >> -__weak u32 arch_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> -{ >> - return default_msi_mask_irq(desc, mask, flag); >> -} >> - >> static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> { >> - desc->masked = arch_msi_mask_irq(desc, mask, flag); >> + desc->masked = __msi_mask_irq(desc, mask, flag); >> } >> >> /* >> @@ -193,11 +189,15 @@ static void msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag) >> * file. This saves a few milliseconds when initialising devices with lots >> * of MSI-X interrupts. >> */ >> -u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag) >> +u32 __msix_mask_irq(struct msi_desc *desc, u32 flag) >> { >> u32 mask_bits = desc->masked; >> unsigned offset = desc->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE + >> PCI_MSIX_ENTRY_VECTOR_CTRL; >> + >> + if (pci_msi_ignore_mask) >> + return 0; >> + >> mask_bits &= ~PCI_MSIX_ENTRY_CTRL_MASKBIT; >> if (flag) >> mask_bits |= PCI_MSIX_ENTRY_CTRL_MASKBIT; >> @@ -206,14 +206,9 @@ u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag) >> return mask_bits; >> } >> >> -__weak u32 arch_msix_mask_irq(struct msi_desc *desc, u32 flag) >> -{ >> - return default_msix_mask_irq(desc, flag); >> -} >> - >> static void msix_mask_irq(struct msi_desc *desc, u32 flag) >> { >> - desc->masked = arch_msix_mask_irq(desc, flag); >> + desc->masked = __msix_mask_irq(desc, flag); >> } >> >> static void msi_set_mask_bit(struct irq_data *data, u32 flag) >> @@ -866,7 +861,7 @@ void pci_msi_shutdown(struct pci_dev *dev) >> /* Return the device with MSI unmasked as initial states */ >> mask = msi_mask(desc->msi_attrib.multi_cap); >> /* Keep cached state to be restored */ >> - arch_msi_mask_irq(desc, mask, ~mask); >> + __msi_mask_irq(desc, mask, ~mask); >> >> /* Restore dev->irq to its default pin-assertion irq */ >> dev->irq = desc->msi_attrib.default_irq; >> @@ -964,7 +959,7 @@ void pci_msix_shutdown(struct pci_dev *dev) >> /* Return the device with MSI-X masked as initial states */ >> list_for_each_entry(entry, &dev->msi_list, list) { >> /* Keep cached states to be restored */ >> - arch_msix_mask_irq(entry, 1); >> + __msix_mask_irq(entry, 1); >> } >> >> msix_clear_and_set_ctrl(dev, PCI_MSIX_FLAGS_ENABLE, 0); >> diff --git a/include/linux/msi.h b/include/linux/msi.h >> index 44f4746..9ac1e3b 100644 >> --- a/include/linux/msi.h >> +++ b/include/linux/msi.h >> @@ -10,6 +10,8 @@ struct msi_msg { >> u32 data; /* 16 bits of msi message data */ >> }; >> >> +extern int pci_msi_ignore_mask; >> + >> /* Helper functions */ >> struct irq_data; >> struct msi_desc; >> @@ -21,6 +23,8 @@ void __write_msi_msg(struct msi_desc *entry, struct msi_msg *msg); >> void read_msi_msg(unsigned int irq, struct msi_msg *msg); >> void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg); >> void write_msi_msg(unsigned int irq, struct msi_msg *msg); >> +u32 __msix_mask_irq(struct msi_desc *desc, u32 flag); >> +u32 __msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag); >> >> struct msi_desc { >> struct { >> @@ -61,8 +65,8 @@ void arch_restore_msi_irqs(struct pci_dev *dev); >> >> void default_teardown_msi_irqs(struct pci_dev *dev); >> void default_restore_msi_irqs(struct pci_dev *dev); >> -u32 default_msi_mask_irq(struct msi_desc *desc, u32 mask, u32 flag); >> -u32 default_msix_mask_irq(struct msi_desc *desc, u32 flag); >> +#define default_msi_mask_irq __msi_mask_irq >> +#define default_msix_mask_irq __msix_mask_irq >> >> struct msi_chip { >> struct module *owner; >> -- >> 1.7.1 >> > > . > -- Thanks! Yijing -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/