From mboxrd@z Thu Jan 1 00:00:00 1970 From: Feng Wu Subject: [PATCH v9 08/17] vmx: Suppress posting interrupts when 'SN' is set Date: Tue, 3 Nov 2015 16:43:18 +0800 Message-ID: <1446540207-4806-9-git-send-email-feng.wu@intel.com> References: <1446540207-4806-1-git-send-email-feng.wu@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1446540207-4806-1-git-send-email-feng.wu@intel.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: xen-devel@lists.xen.org Cc: Keir Fraser , Kevin Tian , Feng Wu , Jan Beulich , Andrew Cooper List-Id: xen-devel@lists.xenproject.org Currently, we don't support urgent interrupt, all interrupts are recognized as non-urgent interrupt, so we cannot send posted-interrupt when 'SN' is set. CC: Kevin Tian CC: Keir Fraser CC: Jan Beulich CC: Andrew Cooper Signed-off-by: Feng Wu Reviewed-by: Konrad Rzeszutek Wilk Reviewed-by: Jan Beulich --- v8: - Parenthesize '1 << POSTED_INTR_ON' and '1 << POSTED_INTR_SN' v7: - Coding style - Read the current pi_desc.control as the intial value of prev.control v6: - Add some comments v5: - keep the vcpu_kick() at the end of vmx_deliver_posted_intr() - Keep the 'return' after calling __vmx_deliver_posted_interrupt() v4: - Coding style. - V3 removes a vcpu_kick() from the eoi_exitmap_changed path incorrectly, fix it. v3: - use cmpxchg to test SN/ON and set ON xen/arch/x86/hvm/vmx/vmx.c | 29 ++++++++++++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-) diff --git a/xen/arch/x86/hvm/vmx/vmx.c b/xen/arch/x86/hvm/vmx/vmx.c index c32d863..741a271 100644 --- a/xen/arch/x86/hvm/vmx/vmx.c +++ b/xen/arch/x86/hvm/vmx/vmx.c @@ -1701,8 +1701,35 @@ static void vmx_deliver_posted_intr(struct vcpu *v, u8 vector) */ pi_set_on(&v->arch.hvm_vmx.pi_desc); } - else if ( !pi_test_and_set_on(&v->arch.hvm_vmx.pi_desc) ) + else { + struct pi_desc old, new, prev; + + prev.control = v->arch.hvm_vmx.pi_desc.control; + + do { + /* + * Currently, we don't support urgent interrupt, all + * interrupts are recognized as non-urgent interrupt, + * so we cannot send posted-interrupt when 'SN' is set. + * Besides that, if 'ON' is already set, we cannot set + * posted-interrupts as well. + */ + if ( pi_test_sn(&prev) || pi_test_on(&prev) ) + { + vcpu_kick(v); + return; + } + + old.control = v->arch.hvm_vmx.pi_desc.control & + ~((1 << POSTED_INTR_ON) | (1 << POSTED_INTR_SN)); + new.control = v->arch.hvm_vmx.pi_desc.control | + (1 << POSTED_INTR_ON); + + prev.control = cmpxchg(&v->arch.hvm_vmx.pi_desc.control, + old.control, new.control); + } while ( prev.control != old.control ); + __vmx_deliver_posted_interrupt(v); return; } -- 2.1.0