From 7deabca0acfe02b8e18f59a4c95676012f49a304 Mon Sep 17 00:00:00 2001 From: Russell King Date: Thu, 19 Jan 2012 15:20:58 +0000 Subject: ARM: fix rcu stalls on SMP platforms We can stall RCU processing on SMP platforms if a CPU sits in its idle loop for a long time. This happens because we don't call irq_enter() and irq_exit() around generic_smp_call_function_interrupt() and friends. Add the necessary calls, and remove the one from within ipi_timer(), so that they're all in a common place. Signed-off-by: Russell King --- arch/arm/kernel/smp.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 57db122a4f62..26cdc494ee9b 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -443,9 +443,7 @@ static DEFINE_PER_CPU(struct clock_event_device, percpu_clockevent); static void ipi_timer(void) { struct clock_event_device *evt = &__get_cpu_var(percpu_clockevent); - irq_enter(); evt->event_handler(evt); - irq_exit(); } #ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST @@ -548,7 +546,9 @@ void handle_IPI(int ipinr, struct pt_regs *regs) switch (ipinr) { case IPI_TIMER: + irq_enter(); ipi_timer(); + irq_exit(); break; case IPI_RESCHEDULE: @@ -556,15 +556,21 @@ void handle_IPI(int ipinr, struct pt_regs *regs) break; case IPI_CALL_FUNC: + irq_enter(); generic_smp_call_function_interrupt(); + irq_exit(); break; case IPI_CALL_FUNC_SINGLE: + irq_enter(); generic_smp_call_function_single_interrupt(); + irq_exit(); break; case IPI_CPU_STOP: + irq_enter(); ipi_cpu_stop(cpu); + irq_exit(); break; default: -- cgit v1.2.3 From a36d8e5bc27316163c9d753af5966ee92ecbec59 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 18 Jan 2012 01:57:21 +0100 Subject: ARM: 7279/1: standardize /proc/iomem "Kernel code" name All other ports use "Kernel code" to identify the Kernel text segment in /proc/iomem. Change the ARM resources to do the same. Signed-off-by: Kees Cook Acked-by: Nicolas Pitre Signed-off-by: Russell King --- arch/arm/kernel/setup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 129fbd55bde8..95653d03db7e 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -160,7 +160,7 @@ static struct resource mem_res[] = { .flags = IORESOURCE_MEM }, { - .name = "Kernel text", + .name = "Kernel code", .start = 0, .end = 0, .flags = IORESOURCE_MEM -- cgit v1.2.3 From 06e9905152cd124c53f571296e9904ea89c1a39a Mon Sep 17 00:00:00 2001 From: Fabio Estevam Date: Fri, 13 Jan 2012 17:06:59 +0100 Subject: ARM: 7277/1: setup.c: Fix build warning by removing unneeded header file Fix the following build warning: CC arch/arm/kernel/setup.o In file included from arch/arm/kernel/setup.c:39: arch/arm/include/asm/elf.h:102:1: warning: "vmcore_elf64_check_arch" redefined In file included from arch/arm/kernel/setup.c:24: include/linux/crash_dump.h:30:1: warning: this is the location of the previous definition Since commit 93a72052 (crash_dump: export is_kdump_kernel to modules, consolidate elfcorehdr_addr, setup_elfcorehdr and saved_max_pfn) the inclusion of is no longer needed. Remove the inclusion of and the build warning is fixed. Signed-off-by: Fabio Estevam Signed-off-by: Russell King --- arch/arm/kernel/setup.c | 1 - 1 file changed, 1 deletion(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index 95653d03db7e..ab70c9124538 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -21,7 +21,6 @@ #include #include #include -#include #include #include #include -- cgit v1.2.3 From f0d5375e3c7b5d7f128af03c5271c328faeb3ae7 Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 20 Jan 2012 11:55:54 +0100 Subject: ARM: 7289/1: vmlinux.lds.S: do not hardcode cacheline size as 32 bytes The linker script assumes a cacheline size of 32 bytes when aligning the .data..cacheline_aligned and .data..percpu sections. This patch updates the script to use L1_CACHE_BYTES, which should be set to 64 on platforms that require it. Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/vmlinux.lds.S | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index f76e75548670..1077e4ff6f3c 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -4,6 +4,7 @@ */ #include +#include #include #include #include @@ -181,7 +182,7 @@ SECTIONS } #endif - PERCPU_SECTION(32) + PERCPU_SECTION(L1_CACHE_BYTES) #ifdef CONFIG_XIP_KERNEL __data_loc = ALIGN(4); /* location in binary */ @@ -212,8 +213,8 @@ SECTIONS #endif NOSAVE_DATA - CACHELINE_ALIGNED_DATA(32) - READ_MOSTLY_DATA(32) + CACHELINE_ALIGNED_DATA(L1_CACHE_BYTES) + READ_MOSTLY_DATA(L1_CACHE_BYTES) /* * The exception fixup table (might need resorting at runtime) -- cgit v1.2.3 From 972da06470519b6eaef9776a586e2353f089de9c Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 20 Jan 2012 12:01:09 +0100 Subject: ARM: 7290/1: vmlinux.lds.S: align the exception fixup table to a 4-byte boundary The exception fixup table is currently aligned to a 32-byte boundary. Whilst this won't cause any problems, the exception_table_entry structures contain only a pair of unsigned longs, so 4-byte alignment is all that is required. If the table was walked from start to end, cacheline alignment may bring some performance benefits, but since a binary search is used, the access pattern is random and will not benefit from a stricter alignment. Acked-by: Nicolas Pitre Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/vmlinux.lds.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/vmlinux.lds.S b/arch/arm/kernel/vmlinux.lds.S index 1077e4ff6f3c..1e19691e0406 100644 --- a/arch/arm/kernel/vmlinux.lds.S +++ b/arch/arm/kernel/vmlinux.lds.S @@ -219,7 +219,7 @@ SECTIONS /* * The exception fixup table (might need resorting at runtime) */ - . = ALIGN(32); + . = ALIGN(4); __start___ex_table = .; #ifdef CONFIG_MMU *(__ex_table) -- cgit v1.2.3 From eb50439b92b6298bf209a982f295ba9c0f7cb30b Mon Sep 17 00:00:00 2001 From: Will Deacon Date: Fri, 20 Jan 2012 12:01:12 +0100 Subject: ARM: 7293/1: logical_cpu_map: decouple CPU mapping from SMP It turns out that the logical CPU mapping is useful even when !CONFIG_SMP for manipulation of devices like interrupt and power controllers when running a UP kernel on a CPU other than 0. This can happen when kexecing a UP image from an SMP kernel. In the future, multi-cluster systems running AMP configurations will require something similar for mapping cluster IDs, so it makes sense to decouple this logic in preparation for this support. Acked-by: Yang Bai Acked-by: Marc Zyngier Reported-by: Joerg Roedel Signed-off-by: Will Deacon Signed-off-by: Russell King --- arch/arm/kernel/setup.c | 14 ++++++++++++++ arch/arm/kernel/smp.c | 14 -------------- 2 files changed, 14 insertions(+), 14 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/setup.c b/arch/arm/kernel/setup.c index ab70c9124538..a255c39612ca 100644 --- a/arch/arm/kernel/setup.c +++ b/arch/arm/kernel/setup.c @@ -426,6 +426,20 @@ void cpu_init(void) : "r14"); } +int __cpu_logical_map[NR_CPUS]; + +void __init smp_setup_processor_id(void) +{ + int i; + u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0; + + cpu_logical_map(0) = cpu; + for (i = 1; i < NR_CPUS; ++i) + cpu_logical_map(i) = i == cpu ? 0 : i; + + printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu); +} + static void __init setup_processor(void) { struct proc_info_list *list; diff --git a/arch/arm/kernel/smp.c b/arch/arm/kernel/smp.c index 26cdc494ee9b..cdeb727527d3 100644 --- a/arch/arm/kernel/smp.c +++ b/arch/arm/kernel/smp.c @@ -233,20 +233,6 @@ void __ref cpu_die(void) } #endif /* CONFIG_HOTPLUG_CPU */ -int __cpu_logical_map[NR_CPUS]; - -void __init smp_setup_processor_id(void) -{ - int i; - u32 cpu = is_smp() ? read_cpuid_mpidr() & 0xff : 0; - - cpu_logical_map(0) = cpu; - for (i = 1; i < NR_CPUS; ++i) - cpu_logical_map(i) = i == cpu ? 0 : i; - - printk(KERN_INFO "Booting Linux on physical CPU %d\n", cpu); -} - /* * Called by both boot and secondaries to move global data into * per-processor storage. -- cgit v1.2.3 From c214455f3205fa20819da6d67a8b20609ff786e7 Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Fri, 20 Jan 2012 12:24:47 +0100 Subject: ARM: 7297/1: smp_twd: make sure timer is stopped before registering it On secondary CPUs, the Timer Control Register is not reset to a sane value before the timer is registered, and the TRM doesn't seem to indicate any reset value either. In some cases, the kernel will take an interrupt too early, depending on what junk was present in the registers at reset time. The fix is to set the Timer Control Register to 0 before registering the clock_event_device and enabling the interrupt. Problem seen on VE (Cortex A5) and Tegra. Signed-off-by: Marc Zyngier Signed-off-by: Russell King --- arch/arm/kernel/smp_twd.c | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index c8e938553d47..4285daa077b0 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -252,6 +252,8 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk) else twd_calibrate_rate(); + __raw_writel(0, twd_base + TWD_TIMER_CONTROL); + clk->name = "local_timer"; clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_C3STOP; -- cgit v1.2.3 From d68133b5a81bd9c4b673c2a731ac1a33a9dc0cb8 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Tue, 24 Jan 2012 16:52:52 +0100 Subject: ARM: 7299/1: ftrace: clear zero bit in reported IPs for Thumb-2 The dynamic ftrace ops startup test currently fails on Thumb-2 kernels: Testing tracer function: PASSED Testing dynamic ftrace: PASSED Testing dynamic ftrace ops #1: (0 0 0 0 0) FAILED! This is because while the addresses in the mcount records do not have the zero bit set, the IP reported by the mcount call does have it set (because it is copied from the LR). This mismatch causes the ops filtering in ftrace_ops_list_func() to not call the relevant tracers. Fix this by clearing the zero bit before adjusting the LR for the mcount instruction size. Also, combine the mov+sub into a single sub instruction. Acked-by: Dave Martin Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- arch/arm/kernel/entry-common.S | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'arch/arm/kernel') diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 520889cf1b5b..9fd0ba90c1d2 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -149,6 +149,11 @@ ENDPROC(ret_from_fork) #endif #endif +.macro mcount_adjust_addr rd, rn + bic \rd, \rn, #1 @ clear the Thumb bit if present + sub \rd, \rd, #MCOUNT_INSN_SIZE +.endm + .macro __mcount suffix mcount_enter ldr r0, =ftrace_trace_function @@ -173,8 +178,7 @@ ENDPROC(ret_from_fork) mcount_exit 1: mcount_get_lr r1 @ lr of instrumented func - mov r0, lr @ instrumented function - sub r0, r0, #MCOUNT_INSN_SIZE + mcount_adjust_addr r0, lr @ instrumented function adr lr, BSYM(2f) mov pc, r2 2: mcount_exit @@ -184,8 +188,7 @@ ENDPROC(ret_from_fork) mcount_enter mcount_get_lr r1 @ lr of instrumented func - mov r0, lr @ instrumented function - sub r0, r0, #MCOUNT_INSN_SIZE + mcount_adjust_addr r0, lr @ instrumented function .globl ftrace_call\suffix ftrace_call\suffix: @@ -205,11 +208,11 @@ ftrace_graph_call\suffix: #ifdef CONFIG_DYNAMIC_FTRACE @ called from __ftrace_caller, saved in mcount_enter ldr r1, [sp, #16] @ instrumented routine (func) + mcount_adjust_addr r1, r1 #else @ called from __mcount, untouched in lr - mov r1, lr @ instrumented routine (func) + mcount_adjust_addr r1, lr @ instrumented routine (func) #endif - sub r1, r1, #MCOUNT_INSN_SIZE mov r2, fp @ frame pointer bl prepare_ftrace_return mcount_exit -- cgit v1.2.3