From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from e23smtp05.au.ibm.com (e23smtp05.au.ibm.com [202.81.31.147]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "e23smtp05.au.ibm.com", Issuer "GeoTrust SSL CA" (not verified)) by ozlabs.org (Postfix) with ESMTPS id E13831007DF for ; Fri, 2 Mar 2012 20:36:17 +1100 (EST) Received: from /spool/local by e23smtp05.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 2 Mar 2012 09:32:29 +1000 Received: from d23av04.au.ibm.com (d23av04.au.ibm.com [9.190.235.139]) by d23relay04.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id q229UbMQ2240740 for ; Fri, 2 Mar 2012 20:30:37 +1100 Received: from d23av04.au.ibm.com (loopback [127.0.0.1]) by d23av04.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id q229a6hN005303 for ; Fri, 2 Mar 2012 20:36:07 +1100 From: Benjamin Herrenschmidt To: linuxppc-dev@ozlabs.org Subject: [PATCH 11/12] powerpc: Replace mfmsr instructions with load from PACA kernel_msr field Date: Fri, 2 Mar 2012 20:35:21 +1100 Message-Id: <1330680922-6894-12-git-send-email-benh@kernel.crashing.org> In-Reply-To: <1330680922-6894-1-git-send-email-benh@kernel.crashing.org> References: <1330680922-6894-1-git-send-email-benh@kernel.crashing.org> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 64-bit, the mfmsr instruction can be quite slow, slower than loading a field from the cache-hot PACA, which happens to already contain the value we want in most cases. Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/include/asm/exception-64s.h | 2 +- arch/powerpc/include/asm/hw_irq.h | 4 ++-- arch/powerpc/kernel/entry_64.S | 14 +++++--------- arch/powerpc/kernel/exceptions-64s.S | 5 ++--- 4 files changed, 10 insertions(+), 15 deletions(-) diff --git a/arch/powerpc/include/asm/exception-64s.h b/arch/powerpc/include/asm/exception-64s.h index 7f4718c..70354af 100644 --- a/arch/powerpc/include/asm/exception-64s.h +++ b/arch/powerpc/include/asm/exception-64s.h @@ -298,7 +298,7 @@ label##_hv: \ /* Exception addition: Keep interrupt state */ #define ENABLE_INTS \ - mfmsr r11; \ + ld r11,PACAKMSR(r13); \ ld r12,_MSR(r1); \ rlwimi r11,r12,0,MSR_EE; \ mtmsrd r11,1 diff --git a/arch/powerpc/include/asm/hw_irq.h b/arch/powerpc/include/asm/hw_irq.h index 531ba00..6c6fa95 100644 --- a/arch/powerpc/include/asm/hw_irq.h +++ b/arch/powerpc/include/asm/hw_irq.h @@ -68,8 +68,8 @@ static inline bool arch_irqs_disabled(void) #define __hard_irq_enable() asm volatile("wrteei 1" : : : "memory"); #define __hard_irq_disable() asm volatile("wrteei 0" : : : "memory"); #else -#define __hard_irq_enable() __mtmsrd(mfmsr() | MSR_EE, 1) -#define __hard_irq_disable() __mtmsrd(mfmsr() & ~MSR_EE, 1) +#define __hard_irq_enable() __mtmsrd(local_paca->kernel_msr | MSR_EE, 1) +#define __hard_irq_disable() __mtmsrd(local_paca->kernel_msr, 1) #endif #define hard_irq_disable() \ diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index cc030b7..c513beb 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -557,10 +557,8 @@ _GLOBAL(ret_from_except_lite) #ifdef CONFIG_PPC_BOOK3E wrteei 0 #else - mfmsr r10 /* Get current interrupt state */ - rldicl r9,r10,48,1 /* clear MSR_EE */ - rotldi r9,r9,16 - mtmsrd r9,1 /* Update machine state */ + ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */ + mtmsrd r10,1 /* Update machine state */ #endif /* CONFIG_PPC_BOOK3E */ #ifdef CONFIG_PREEMPT @@ -625,8 +623,8 @@ ALT_FTR_SECTION_END_IFCLR(CPU_FTR_STCX_CHECKS_ADDRESS) * userspace and we take an exception after restoring r13, * we end up corrupting the userspace r13 value. */ - mfmsr r4 - andc r4,r4,r0 /* r0 contains MSR_RI here */ + ld r4,PACAKMSR(r13) /* Get kernel MSR without EE */ + andc r4,r4,r0 /* r0 contains MSR_RI here */ mtmsrd r4,1 /* @@ -686,9 +684,7 @@ do_work: #ifdef CONFIG_PPC_BOOK3E wrteei 0 #else - mfmsr r10 - rldicl r10,r10,48,1 - rotldi r10,r10,16 + ld r10,PACAKMSR(r13) /* Get kernel MSR without EE */ mtmsrd r10,1 #endif /* CONFIG_PPC_BOOK3E */ li r0,0 diff --git a/arch/powerpc/kernel/exceptions-64s.S b/arch/powerpc/kernel/exceptions-64s.S index bd7130c..880f360 100644 --- a/arch/powerpc/kernel/exceptions-64s.S +++ b/arch/powerpc/kernel/exceptions-64s.S @@ -850,9 +850,8 @@ fast_exception_return: REST_GPR(0, r1) REST_8GPRS(2, r1) - mfmsr r10 - rldicl r10,r10,48,1 /* clear EE */ - rldicr r10,r10,16,61 /* clear RI (LE is 0 already) */ + ld r10,PACAKMSR(r13) + clrrdi r10,r10,2 /* clear RI */ mtmsrd r10,1 mtspr SPRN_SRR1,r12 -- 1.7.9