diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-14 03:49:59 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-05-14 03:49:59 +0400 |
commit | c83bb88589f444d12e31d1d55c6c4d7d47cba3d4 (patch) | |
tree | 7c2d993ad6fd87d56d868189b7958c65b712eefb | |
parent | dbbffe6898fd0d7bac66ded5d3c58835b13ddefc (diff) | |
parent | 6880b0150a7c25fd75c5ece80abc49ebf53c38c1 (diff) | |
download | linux-c83bb88589f444d12e31d1d55c6c4d7d47cba3d4.tar.xz |
Merge branch 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux
Pull parisc update from Helge Deller:
"The second round of parisc updates for 3.10 includes build fixes and
enhancements to utilize irq stacks, fixes SMP races when updating PTE
and TLB entries by proper locking and makes the search for the correct
cross compiler more robust on Debian and Gentoo."
* 'parisc-for-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: make default cross compiler search more robust (v3)
parisc: fix SMP races when updating PTE and TLB entries in entry.S
parisc: implement irq stacks - part 2 (v2)
-rw-r--r-- | arch/parisc/Kconfig | 2 | ||||
-rw-r--r-- | arch/parisc/Makefile | 21 | ||||
-rw-r--r-- | arch/parisc/include/asm/hardirq.h | 9 | ||||
-rw-r--r-- | arch/parisc/include/asm/processor.h | 3 | ||||
-rw-r--r-- | arch/parisc/kernel/entry.S | 155 | ||||
-rw-r--r-- | arch/parisc/kernel/irq.c | 101 | ||||
-rw-r--r-- | arch/parisc/mm/init.c | 4 |
7 files changed, 194 insertions, 101 deletions
diff --git a/arch/parisc/Kconfig b/arch/parisc/Kconfig index cad060f288cf..6507dabdd5dd 100644 --- a/arch/parisc/Kconfig +++ b/arch/parisc/Kconfig @@ -245,7 +245,7 @@ config SMP config IRQSTACKS bool "Use separate kernel stacks when processing interrupts" - default n + default y help If you say Y here the kernel will use separate kernel stacks for handling hard and soft interrupts. This can help avoid diff --git a/arch/parisc/Makefile b/arch/parisc/Makefile index 2f967cc6649e..197690068f88 100644 --- a/arch/parisc/Makefile +++ b/arch/parisc/Makefile @@ -23,24 +23,21 @@ NM = sh $(srctree)/arch/parisc/nm CHECKFLAGS += -D__hppa__=1 LIBGCC = $(shell $(CC) $(KBUILD_CFLAGS) -print-libgcc-file-name) -MACHINE := $(shell uname -m) -NATIVE := $(if $(filter parisc%,$(MACHINE)),1,0) - ifdef CONFIG_64BIT UTS_MACHINE := parisc64 CHECKFLAGS += -D__LP64__=1 -m64 -WIDTH := 64 +CC_ARCHES = hppa64 else # 32-bit -WIDTH := +CC_ARCHES = hppa hppa2.0 hppa1.1 endif -# attempt to help out folks who are cross-compiling -ifeq ($(NATIVE),1) -CROSS_COMPILE := hppa$(WIDTH)-linux- -else - ifeq ($(CROSS_COMPILE),) - CROSS_COMPILE := hppa$(WIDTH)-linux-gnu- - endif +ifneq ($(SUBARCH),$(UTS_MACHINE)) + ifeq ($(CROSS_COMPILE),) + CC_SUFFIXES = linux linux-gnu unknown-linux-gnu + CROSS_COMPILE := $(call cc-cross-prefix, \ + $(foreach a,$(CC_ARCHES), \ + $(foreach s,$(CC_SUFFIXES),$(a)-$(s)-))) + endif endif OBJCOPY_FLAGS =-O binary -R .note -R .comment -S diff --git a/arch/parisc/include/asm/hardirq.h b/arch/parisc/include/asm/hardirq.h index 12373c4dabab..c19f7138ba48 100644 --- a/arch/parisc/include/asm/hardirq.h +++ b/arch/parisc/include/asm/hardirq.h @@ -11,10 +11,18 @@ #include <linux/threads.h> #include <linux/irq.h> +#ifdef CONFIG_IRQSTACKS +#define __ARCH_HAS_DO_SOFTIRQ +#endif + typedef struct { unsigned int __softirq_pending; #ifdef CONFIG_DEBUG_STACKOVERFLOW unsigned int kernel_stack_usage; +#ifdef CONFIG_IRQSTACKS + unsigned int irq_stack_usage; + unsigned int irq_stack_counter; +#endif #endif #ifdef CONFIG_SMP unsigned int irq_resched_count; @@ -28,6 +36,7 @@ DECLARE_PER_CPU_SHARED_ALIGNED(irq_cpustat_t, irq_stat); #define __ARCH_IRQ_STAT #define __IRQ_STAT(cpu, member) (irq_stat[cpu].member) #define inc_irq_stat(member) this_cpu_inc(irq_stat.member) +#define __inc_irq_stat(member) __this_cpu_inc(irq_stat.member) #define local_softirq_pending() this_cpu_read(irq_stat.__softirq_pending) #define __ARCH_SET_SOFTIRQ_PENDING diff --git a/arch/parisc/include/asm/processor.h b/arch/parisc/include/asm/processor.h index 064015547d1e..cfbc43929cf6 100644 --- a/arch/parisc/include/asm/processor.h +++ b/arch/parisc/include/asm/processor.h @@ -63,10 +63,13 @@ */ #ifdef __KERNEL__ +#include <linux/spinlock_types.h> + #define IRQ_STACK_SIZE (4096 << 2) /* 16k irq stack size */ union irq_stack_union { unsigned long stack[IRQ_STACK_SIZE/sizeof(unsigned long)]; + raw_spinlock_t lock; }; DECLARE_PER_CPU(union irq_stack_union, irq_stack_union); diff --git a/arch/parisc/kernel/entry.S b/arch/parisc/kernel/entry.S index 4bb96ad9b0b1..ae27cb6ce19a 100644 --- a/arch/parisc/kernel/entry.S +++ b/arch/parisc/kernel/entry.S @@ -452,9 +452,41 @@ L2_ptep \pgd,\pte,\index,\va,\fault .endm + /* Acquire pa_dbit_lock lock. */ + .macro dbit_lock spc,tmp,tmp1 +#ifdef CONFIG_SMP + cmpib,COND(=),n 0,\spc,2f + load32 PA(pa_dbit_lock),\tmp +1: LDCW 0(\tmp),\tmp1 + cmpib,COND(=) 0,\tmp1,1b + nop +2: +#endif + .endm + + /* Release pa_dbit_lock lock without reloading lock address. */ + .macro dbit_unlock0 spc,tmp +#ifdef CONFIG_SMP + or,COND(=) %r0,\spc,%r0 + stw \spc,0(\tmp) +#endif + .endm + + /* Release pa_dbit_lock lock. */ + .macro dbit_unlock1 spc,tmp +#ifdef CONFIG_SMP + load32 PA(pa_dbit_lock),\tmp + dbit_unlock0 \spc,\tmp +#endif + .endm + /* Set the _PAGE_ACCESSED bit of the PTE. Be clever and * don't needlessly dirty the cache line if it was already set */ - .macro update_ptep ptep,pte,tmp,tmp1 + .macro update_ptep spc,ptep,pte,tmp,tmp1 +#ifdef CONFIG_SMP + or,COND(=) %r0,\spc,%r0 + LDREG 0(\ptep),\pte +#endif ldi _PAGE_ACCESSED,\tmp1 or \tmp1,\pte,\tmp and,COND(<>) \tmp1,\pte,%r0 @@ -463,7 +495,11 @@ /* Set the dirty bit (and accessed bit). No need to be * clever, this is only used from the dirty fault */ - .macro update_dirty ptep,pte,tmp + .macro update_dirty spc,ptep,pte,tmp +#ifdef CONFIG_SMP + or,COND(=) %r0,\spc,%r0 + LDREG 0(\ptep),\pte +#endif ldi _PAGE_ACCESSED|_PAGE_DIRTY,\tmp or \tmp,\pte,\pte STREG \pte,0(\ptep) @@ -1111,11 +1147,13 @@ dtlb_miss_20w: L3_ptep ptp,pte,t0,va,dtlb_check_alias_20w - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1135,11 +1173,13 @@ nadtlb_miss_20w: L3_ptep ptp,pte,t0,va,nadtlb_check_alias_20w - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1161,7 +1201,8 @@ dtlb_miss_11: L2_ptep ptp,pte,t0,va,dtlb_check_alias_11 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot @@ -1172,6 +1213,7 @@ dtlb_miss_11: idtlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ + dbit_unlock1 spc,t0 rfir nop @@ -1192,7 +1234,8 @@ nadtlb_miss_11: L2_ptep ptp,pte,t0,va,nadtlb_check_alias_11 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot @@ -1204,6 +1247,7 @@ nadtlb_miss_11: idtlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ + dbit_unlock1 spc,t0 rfir nop @@ -1224,13 +1268,15 @@ dtlb_miss_20: L2_ptep ptp,pte,t0,va,dtlb_check_alias_20 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 idtlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1250,13 +1296,15 @@ nadtlb_miss_20: L2_ptep ptp,pte,t0,va,nadtlb_check_alias_20 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 idtlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1357,11 +1405,13 @@ itlb_miss_20w: L3_ptep ptp,pte,t0,va,itlb_fault - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot iitlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1379,11 +1429,13 @@ naitlb_miss_20w: L3_ptep ptp,pte,t0,va,naitlb_check_alias_20w - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot iitlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1405,7 +1457,8 @@ itlb_miss_11: L2_ptep ptp,pte,t0,va,itlb_fault - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot @@ -1416,6 +1469,7 @@ itlb_miss_11: iitlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ + dbit_unlock1 spc,t0 rfir nop @@ -1427,7 +1481,8 @@ naitlb_miss_11: L2_ptep ptp,pte,t0,va,naitlb_check_alias_11 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb_11 spc,pte,prot @@ -1438,6 +1493,7 @@ naitlb_miss_11: iitlbp prot,(%sr1,va) mtsp t0, %sr1 /* Restore sr1 */ + dbit_unlock1 spc,t0 rfir nop @@ -1459,13 +1515,15 @@ itlb_miss_20: L2_ptep ptp,pte,t0,va,itlb_fault - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 iitlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1477,13 +1535,15 @@ naitlb_miss_20: L2_ptep ptp,pte,t0,va,naitlb_check_alias_20 - update_ptep ptp,pte,t0,t1 + dbit_lock spc,t0,t1 + update_ptep spc,ptp,pte,t0,t1 make_insert_tlb spc,pte,prot f_extend pte,t0 iitlbt pte,prot + dbit_unlock1 spc,t0 rfir nop @@ -1507,29 +1567,13 @@ dbit_trap_20w: L3_ptep ptp,pte,t0,va,dbit_fault -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nolock_20w - load32 PA(pa_dbit_lock),t0 - -dbit_spin_20w: - LDCW 0(t0),t1 - cmpib,COND(=) 0,t1,dbit_spin_20w - nop - -dbit_nolock_20w: -#endif - update_dirty ptp,pte,t1 + dbit_lock spc,t0,t1 + update_dirty spc,ptp,pte,t1 make_insert_tlb spc,pte,prot idtlbt pte,prot -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nounlock_20w - ldi 1,t1 - stw t1,0(t0) - -dbit_nounlock_20w: -#endif + dbit_unlock0 spc,t0 rfir nop @@ -1543,18 +1587,8 @@ dbit_trap_11: L2_ptep ptp,pte,t0,va,dbit_fault -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nolock_11 - load32 PA(pa_dbit_lock),t0 - -dbit_spin_11: - LDCW 0(t0),t1 - cmpib,= 0,t1,dbit_spin_11 - nop - -dbit_nolock_11: -#endif - update_dirty ptp,pte,t1 + dbit_lock spc,t0,t1 + update_dirty spc,ptp,pte,t1 make_insert_tlb_11 spc,pte,prot @@ -1565,13 +1599,7 @@ dbit_nolock_11: idtlbp prot,(%sr1,va) mtsp t1, %sr1 /* Restore sr1 */ -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nounlock_11 - ldi 1,t1 - stw t1,0(t0) - -dbit_nounlock_11: -#endif + dbit_unlock0 spc,t0 rfir nop @@ -1583,32 +1611,15 @@ dbit_trap_20: L2_ptep ptp,pte,t0,va,dbit_fault -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nolock_20 - load32 PA(pa_dbit_lock),t0 - -dbit_spin_20: - LDCW 0(t0),t1 - cmpib,= 0,t1,dbit_spin_20 - nop - -dbit_nolock_20: -#endif - update_dirty ptp,pte,t1 + dbit_lock spc,t0,t1 + update_dirty spc,ptp,pte,t1 make_insert_tlb spc,pte,prot f_extend pte,t1 idtlbt pte,prot - -#ifdef CONFIG_SMP - cmpib,COND(=),n 0,spc,dbit_nounlock_20 - ldi 1,t1 - stw t1,0(t0) - -dbit_nounlock_20: -#endif + dbit_unlock0 spc,t0 rfir nop diff --git a/arch/parisc/kernel/irq.c b/arch/parisc/kernel/irq.c index e255db0bb761..55237a70e197 100644 --- a/arch/parisc/kernel/irq.c +++ b/arch/parisc/kernel/irq.c @@ -166,22 +166,32 @@ int arch_show_interrupts(struct seq_file *p, int prec) seq_printf(p, "%*s: ", prec, "STK"); for_each_online_cpu(j) seq_printf(p, "%10u ", irq_stats(j)->kernel_stack_usage); - seq_printf(p, " Kernel stack usage\n"); + seq_puts(p, " Kernel stack usage\n"); +# ifdef CONFIG_IRQSTACKS + seq_printf(p, "%*s: ", prec, "IST"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_stack_usage); + seq_puts(p, " Interrupt stack usage\n"); + seq_printf(p, "%*s: ", prec, "ISC"); + for_each_online_cpu(j) + seq_printf(p, "%10u ", irq_stats(j)->irq_stack_counter); + seq_puts(p, " Interrupt stack usage counter\n"); +# endif #endif #ifdef CONFIG_SMP seq_printf(p, "%*s: ", prec, "RES"); for_each_online_cpu(j) seq_printf(p, "%10u ", irq_stats(j)->irq_resched_count); - seq_printf(p, " Rescheduling interrupts\n"); + seq_puts(p, " Rescheduling interrupts\n"); seq_printf(p, "%*s: ", prec, "CAL"); for_each_online_cpu(j) seq_printf(p, "%10u ", irq_stats(j)->irq_call_count); - seq_printf(p, " Function call interrupts\n"); + seq_puts(p, " Function call interrupts\n"); #endif seq_printf(p, "%*s: ", prec, "TLB"); for_each_online_cpu(j) seq_printf(p, "%10u ", irq_stats(j)->irq_tlb_count); - seq_printf(p, " TLB shootdowns\n"); + seq_puts(p, " TLB shootdowns\n"); return 0; } @@ -378,6 +388,7 @@ static inline void stack_overflow_check(struct pt_regs *regs) unsigned long sp = regs->gr[30]; unsigned long stack_usage; unsigned int *last_usage; + int cpu = smp_processor_id(); /* if sr7 != 0, we interrupted a userspace process which we do not want * to check for stack overflow. We will only check the kernel stack. */ @@ -386,7 +397,31 @@ static inline void stack_overflow_check(struct pt_regs *regs) /* calculate kernel stack usage */ stack_usage = sp - stack_start; - last_usage = &per_cpu(irq_stat.kernel_stack_usage, smp_processor_id()); +#ifdef CONFIG_IRQSTACKS + if (likely(stack_usage <= THREAD_SIZE)) + goto check_kernel_stack; /* found kernel stack */ + + /* check irq stack usage */ + stack_start = (unsigned long) &per_cpu(irq_stack_union, cpu).stack; + stack_usage = sp - stack_start; + + last_usage = &per_cpu(irq_stat.irq_stack_usage, cpu); + if (unlikely(stack_usage > *last_usage)) + *last_usage = stack_usage; + + if (likely(stack_usage < (IRQ_STACK_SIZE - STACK_MARGIN))) + return; + + pr_emerg("stackcheck: %s will most likely overflow irq stack " + "(sp:%lx, stk bottom-top:%lx-%lx)\n", + current->comm, sp, stack_start, stack_start + IRQ_STACK_SIZE); + goto panic_check; + +check_kernel_stack: +#endif + + /* check kernel stack usage */ + last_usage = &per_cpu(irq_stat.kernel_stack_usage, cpu); if (unlikely(stack_usage > *last_usage)) *last_usage = stack_usage; @@ -398,31 +433,69 @@ static inline void stack_overflow_check(struct pt_regs *regs) "(sp:%lx, stk bottom-top:%lx-%lx)\n", current->comm, sp, stack_start, stack_start + THREAD_SIZE); +#ifdef CONFIG_IRQSTACKS +panic_check: +#endif if (sysctl_panic_on_stackoverflow) panic("low stack detected by irq handler - check messages\n"); #endif } #ifdef CONFIG_IRQSTACKS -DEFINE_PER_CPU(union irq_stack_union, irq_stack_union); +DEFINE_PER_CPU(union irq_stack_union, irq_stack_union) = { + .lock = __RAW_SPIN_LOCK_UNLOCKED((irq_stack_union).lock) + }; static void execute_on_irq_stack(void *func, unsigned long param1) { - unsigned long *irq_stack_start; + union irq_stack_union *union_ptr; unsigned long irq_stack; - int cpu = smp_processor_id(); + raw_spinlock_t *irq_stack_in_use; - irq_stack_start = &per_cpu(irq_stack_union, cpu).stack[0]; - irq_stack = (unsigned long) irq_stack_start; - irq_stack = ALIGN(irq_stack, 16); /* align for stack frame usage */ + union_ptr = &per_cpu(irq_stack_union, smp_processor_id()); + irq_stack = (unsigned long) &union_ptr->stack; + irq_stack = ALIGN(irq_stack + sizeof(irq_stack_union.lock), + 64); /* align for stack frame usage */ - BUG_ON(*irq_stack_start); /* report bug if we were called recursive. */ - *irq_stack_start = 1; + /* We may be called recursive. If we are already using the irq stack, + * just continue to use it. Use spinlocks to serialize + * the irq stack usage. + */ + irq_stack_in_use = &union_ptr->lock; + if (!raw_spin_trylock(irq_stack_in_use)) { + void (*direct_call)(unsigned long p1) = func; + + /* We are using the IRQ stack already. + * Do direct call on current stack. */ + direct_call(param1); + return; + } /* This is where we switch to the IRQ stack. */ call_on_stack(param1, func, irq_stack); - *irq_stack_start = 0; + __inc_irq_stat(irq_stack_counter); + + /* free up irq stack usage. */ + do_raw_spin_unlock(irq_stack_in_use); +} + +asmlinkage void do_softirq(void) +{ + __u32 pending; + unsigned long flags; + + if (in_interrupt()) + return; + + local_irq_save(flags); + + pending = local_softirq_pending(); + + if (pending) + execute_on_irq_stack(__do_softirq, 0); + + local_irq_restore(flags); } #endif /* CONFIG_IRQSTACKS */ diff --git a/arch/parisc/mm/init.c b/arch/parisc/mm/init.c index ce939ac8622b..1c965642068b 100644 --- a/arch/parisc/mm/init.c +++ b/arch/parisc/mm/init.c @@ -1069,7 +1069,7 @@ void flush_tlb_all(void) { int do_recycle; - inc_irq_stat(irq_tlb_count); + __inc_irq_stat(irq_tlb_count); do_recycle = 0; spin_lock(&sid_lock); if (dirty_space_ids > RECYCLE_THRESHOLD) { @@ -1090,7 +1090,7 @@ void flush_tlb_all(void) #else void flush_tlb_all(void) { - inc_irq_stat(irq_tlb_count); + __inc_irq_stat(irq_tlb_count); spin_lock(&sid_lock); flush_tlb_all_local(NULL); recycle_sids(); |