From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3wz6d163mmzDr57 for ; Fri, 30 Jun 2017 03:50:13 +1000 (AEST) Received: from pps.filterd (m0098420.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.20/8.16.0.20) with SMTP id v5THmphf079445 for ; Thu, 29 Jun 2017 13:50:11 -0400 Received: from e23smtp04.au.ibm.com (e23smtp04.au.ibm.com [202.81.31.146]) by mx0b-001b2d01.pphosted.com with ESMTP id 2bd03baecd-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 29 Jun 2017 13:50:10 -0400 Received: from localhost by e23smtp04.au.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Fri, 30 Jun 2017 03:50:06 +1000 Received: from d23av06.au.ibm.com (d23av06.au.ibm.com [9.190.235.151]) by d23relay06.au.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id v5THo2FX4456744 for ; Fri, 30 Jun 2017 03:50:02 +1000 Received: from d23av06.au.ibm.com (localhost [127.0.0.1]) by d23av06.au.ibm.com (8.14.4/8.14.4/NCO v10.0 AVout) with ESMTP id v5THo1nP030970 for ; Fri, 30 Jun 2017 03:50:02 +1000 From: "Naveen N. Rao" To: Michael Ellerman Cc: Nicholas Piggin , Ananth N Mavinakayanahalli , Masami Hiramatsu , Anton Blanchard , linuxppc-dev@lists.ozlabs.org Subject: [PATCH v5 4/7] powerpc/64s: Move system_call() symbol to just after setting MSR_EE Date: Thu, 29 Jun 2017 23:19:17 +0530 In-Reply-To: References: In-Reply-To: References: Message-Id: List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , It is common to get a PMU interrupt right after the mtmsr instruction that enables interrupts. Due to this, the stack trace profile gets needlessly split across system_call_common() and system_call(). Previously, system_call() symbol was at the current place to hide a few earlier symbols which have since been made private or removed entirely. So, let's move system_call() slightly higher up, right after the mtmsr instruction that enables interrupts. Convert existing references to system_call to a local syscall symbol. Suggested-by: Nicholas Piggin Reviewed-by: Nicholas Piggin Signed-off-by: Naveen N. Rao --- arch/powerpc/kernel/entry_64.S | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S index ef8e6615b8ba..c39436706555 100644 --- a/arch/powerpc/kernel/entry_64.S +++ b/arch/powerpc/kernel/entry_64.S @@ -142,6 +142,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) mtmsrd r11,1 #endif /* CONFIG_PPC_BOOK3E */ +system_call: /* label this so stack traces look sane */ /* We do need to set SOFTE in the stack frame or the return * from interrupt will be painful */ @@ -155,7 +156,7 @@ END_FW_FTR_SECTION_IFSET(FW_FEATURE_SPLPAR) cmpldi 0,r0,NR_syscalls bge- .Lsyscall_enosys -system_call: /* label this so stack traces look sane */ +.Lsyscall: /* * Need to vector to 32 Bit or default sys_call_table here, * based on caller's run-mode / personality. @@ -309,13 +310,13 @@ END_FTR_SECTION_IFSET(CPU_FTR_HAS_PPR) ld r7,GPR7(r1) ld r8,GPR8(r1) - /* Repopulate r9 and r10 for the system_call path */ + /* Repopulate r9 and r10 for the syscall path */ addi r9,r1,STACK_FRAME_OVERHEAD CURRENT_THREAD_INFO(r10, r1) ld r10,TI_FLAGS(r10) cmpldi r0,NR_syscalls - blt+ system_call + blt+ .Lsyscall /* Return code is already in r3 thanks to do_syscall_trace_enter() */ b .Lsyscall_exit -- 2.13.1