From da1677b02d3ef674dfd8a4ba1ed32153dc717fa2 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Tue, 14 May 2013 13:28:17 +0530 Subject: ARC: Disintegrate arcregs.h * Move the various sub-system defines/types into relevant files/functions (reduces compilation time) * move CPU specific stuff out of asm/tlb.h into asm/mmu.h Signed-off-by: Vineet Gupta --- arch/arc/mm/fault.c | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/arc/mm/fault.c') diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index 689ffd86d5e9..c0decc1f8d22 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -15,6 +15,7 @@ #include #include #include +#include static int handle_vmalloc_fault(struct mm_struct *mm, unsigned long address) { -- cgit v1.2.3 From 3e1ae441886b82fbf605f37ac0756b811d55f3d5 Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Wed, 12 Jun 2013 13:49:02 +0530 Subject: ARC: [mm] Remove @write argument to do_page_fault() This can be ascertained within do_page_fault() since it gets the full ECR (Exception Cause Register). Further, for both the callers of do_page_fault(): Prot-V / D-TLB-Miss, the cause sub-fields in ECR are same for same type of access, making the code much more simpler. D-TLB-Miss [LD] 0x00_21_01_00 Prot-V [LD] 0x00_23_01_00 ^^ D-TLB-Miss [ST] 0x00_21_02_00 Prot-V [ST] 0x00_23_02_00 ^^ D-TLB-Miss [EX] 0x00_21_03_00 Prot-V [EX] 0x00_23_03_00 ^^ This helps code consolidation, which is even better when moving code from assembler to "C". Signed-off-by: Vineet Gupta --- arch/arc/mm/fault.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/arc/mm/fault.c') diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index c0decc1f8d22..fdafeb1917cc 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -52,7 +52,7 @@ bad_area: return 1; } -void do_page_fault(struct pt_regs *regs, int write, unsigned long address, +void do_page_fault(struct pt_regs *regs, unsigned long address, unsigned long cause_code) { struct vm_area_struct *vma = NULL; @@ -60,6 +60,7 @@ void do_page_fault(struct pt_regs *regs, int write, unsigned long address, struct mm_struct *mm = tsk->mm; siginfo_t info; int fault, ret; + int write = cause_code & (1 << ECR_C_BIT_DTLB_ST_MISS); /* ST/EX */ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | (write ? FAULT_FLAG_WRITE : 0); -- cgit v1.2.3 From 38a9ff6d247cf9afcbe55ea245b650b8955029fd Mon Sep 17 00:00:00 2001 From: Vineet Gupta Date: Wed, 12 Jun 2013 15:13:40 +0530 Subject: ARC: Remove explicit passing around of ECR With ECR now part of pt_regs * No need to propagate from lowest asm handlers as arg * No need to save it in tsk->thread.cause_code * Avoid bit chopping to access the bit-fields More code consolidation, cleanup Signed-off-by: Vineet Gupta --- arch/arc/mm/fault.c | 12 +++++------- 1 file changed, 5 insertions(+), 7 deletions(-) (limited to 'arch/arc/mm/fault.c') diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index fdafeb1917cc..318164cabdfc 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -52,15 +52,14 @@ bad_area: return 1; } -void do_page_fault(struct pt_regs *regs, unsigned long address, - unsigned long cause_code) +void do_page_fault(struct pt_regs *regs, unsigned long address) { struct vm_area_struct *vma = NULL; struct task_struct *tsk = current; struct mm_struct *mm = tsk->mm; siginfo_t info; int fault, ret; - int write = cause_code & (1 << ECR_C_BIT_DTLB_ST_MISS); /* ST/EX */ + int write = regs->ecr_cause & ECR_C_PROTV_STORE; /* ST/EX */ unsigned int flags = FAULT_FLAG_ALLOW_RETRY | FAULT_FLAG_KILLABLE | (write ? FAULT_FLAG_WRITE : 0); @@ -111,7 +110,8 @@ good_area: /* Handle protection violation, execute on heap or stack */ - if (cause_code == ((ECR_V_PROTV << 16) | ECR_C_PROTV_INST_FETCH)) + if ((regs->ecr_vec == ECR_V_PROTV) && + (regs->ecr_cause == ECR_C_PROTV_INST_FETCH)) goto bad_area; if (write) { @@ -178,7 +178,6 @@ bad_area_nosemaphore: /* User mode accesses just cause a SIGSEGV */ if (user_mode(regs)) { tsk->thread.fault_address = address; - tsk->thread.cause_code = cause_code; info.si_signo = SIGSEGV; info.si_errno = 0; /* info.si_code has been set above */ @@ -199,7 +198,7 @@ no_context: if (fixup_exception(regs)) return; - die("Oops", regs, address, cause_code); + die("Oops", regs, address); out_of_memory: if (is_global_init(tsk)) { @@ -220,7 +219,6 @@ do_sigbus: goto no_context; tsk->thread.fault_address = address; - tsk->thread.cause_code = cause_code; info.si_signo = SIGBUS; info.si_errno = 0; info.si_code = BUS_ADRERR; -- cgit v1.2.3 From 609838cfed972d49a65aac7923a9ff5cbe482e30 Mon Sep 17 00:00:00 2001 From: Johannes Weiner Date: Mon, 8 Jul 2013 15:59:50 -0700 Subject: mm: invoke oom-killer from remaining unconverted page fault handlers A few remaining architectures directly kill the page faulting task in an out of memory situation. This is usually not a good idea since that task might not even use a significant amount of memory and so may not be the optimal victim to resolve the situation. Since 2.6.29's 1c0fe6e ("mm: invoke oom-killer from page fault") there is a hook that architecture page fault handlers are supposed to call to invoke the OOM killer and let it pick the right task to kill. Convert the remaining architectures over to this hook. To have the previous behavior of simply taking out the faulting task the vm.oom_kill_allocating_task sysctl can be set to 1. Signed-off-by: Johannes Weiner Reviewed-by: Michal Hocko Cc: KAMEZAWA Hiroyuki Acked-by: David Rientjes Acked-by: Vineet Gupta [arch/arc bits] Cc: James Hogan Cc: David Howells Cc: Jonas Bonn Cc: Chen Liqin Cc: Lennox Wu Cc: Chris Metcalf Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arc/mm/fault.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'arch/arc/mm/fault.c') diff --git a/arch/arc/mm/fault.c b/arch/arc/mm/fault.c index 318164cabdfc..0fd1f0d515ff 100644 --- a/arch/arc/mm/fault.c +++ b/arch/arc/mm/fault.c @@ -207,8 +207,10 @@ out_of_memory: } up_read(&mm->mmap_sem); - if (user_mode(regs)) - do_group_exit(SIGKILL); /* This will never return */ + if (user_mode(regs)) { + pagefault_out_of_memory(); + return; + } goto no_context; -- cgit v1.2.3