From db949bba3c7cf2e664ac12e237c6d4c914f0c69d Mon Sep 17 00:00:00 2001 From: Jeremy Fitzhardinge Date: Fri, 27 Feb 2009 13:25:21 -0800 Subject: x86-32: use non-lazy io bitmap context switching Impact: remove 32-bit optimization to prepare unification x86-32 and -64 differ in the way they context-switch tasks with io permission bitmaps. x86-64 simply copies the next tasks io bitmap into place (if any) on context switch. x86-32 invalidates the bitmap on context switch, so that the next IO instruction will fault; at that point it installs the appropriate IO bitmap. This makes context switching IO-bitmap-using tasks a bit more less expensive, at the cost of making the next IO instruction slower due to the extra fault. This tradeoff only makes sense if IO-bitmap-using processes are relatively common, but they don't actually use IO instructions very often. However, in a typical desktop system, the only process likely to be using IO bitmaps is the X server, and nothing at all on a server. Therefore the lazy context switch doesn't really win all that much, and its just a gratuitious difference from 64-bit code. This patch removes the lazy context switch, with a view to unifying this code in a later change. Signed-off-by: Jeremy Fitzhardinge Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 6 ------ 1 file changed, 6 deletions(-) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index c7a98f738210..76139506c3e4 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -248,7 +248,6 @@ struct x86_hw_tss { #define IO_BITMAP_LONGS (IO_BITMAP_BYTES/sizeof(long)) #define IO_BITMAP_OFFSET offsetof(struct tss_struct, io_bitmap) #define INVALID_IO_BITMAP_OFFSET 0x8000 -#define INVALID_IO_BITMAP_OFFSET_LAZY 0x9000 struct tss_struct { /* @@ -263,11 +262,6 @@ struct tss_struct { * be within the limit. */ unsigned long io_bitmap[IO_BITMAP_LONGS + 1]; - /* - * Cache the current maximum and the last task that used the bitmap: - */ - unsigned long io_bitmap_max; - struct thread_struct *io_bitmap_owner; /* * .. and then another 0x100 bytes for the emergency kernel stack: -- cgit v1.2.2 From 13c6c53282d99c82e79b02477efd2c1e30a991ef Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Thu, 12 Mar 2009 12:37:34 +0000 Subject: x86, 32-bit: also use cpuinfo_x86's x86_{phys,virt}_bits members Impact: 32/64-bit consolidation In a first step, this allows fixing phys_addr_valid() for PAE (which until now reported all addresses to be valid). Subsequently, this will also allow simplifying some MTRR handling code. Signed-off-by: Jan Beulich LKML-Reference: <49B9101E.76E4.0078.0@novell.com> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 76139506c3e4..bd3406db1d68 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -75,9 +75,9 @@ struct cpuinfo_x86 { #else /* Number of 4K pages in DTLB/ITLB combined(in pages): */ int x86_tlbsize; +#endif __u8 x86_virt_bits; __u8 x86_phys_bits; -#endif /* CPUID returned core id bits: */ __u8 x86_coreid_bits; /* Max extended CPUID function supported: */ -- cgit v1.2.2 From 155dd720d06a219ddf5a56b473cb3325441fc879 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Fri, 13 Mar 2009 14:49:53 +1030 Subject: cpumask: convert struct cpuinfo_x86's llc_shared_map to cpumask_var_t Impact: reduce kernel memory usage when CONFIG_CPUMASK_OFFSTACK=y Signed-off-by: Rusty Russell --- arch/x86/include/asm/processor.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 76139506c3e4..d794d9483c56 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -94,7 +94,7 @@ struct cpuinfo_x86 { unsigned long loops_per_jiffy; #ifdef CONFIG_SMP /* cpus sharing the last level cache: */ - cpumask_t llc_shared_map; + cpumask_var_t llc_shared_map; #endif /* cpuid returned max cores value: */ u16 x86_max_cores; -- cgit v1.2.2 From 9766cdbcb260389669e9679b2aa87c11832f479f Mon Sep 17 00:00:00 2001 From: Jaswinder Singh Rajput Date: Sat, 14 Mar 2009 11:19:49 +0530 Subject: x86: cpu/common.c cleanups - fix various style problems - declare varibles before they get used - introduced clear_all_debug_regs - fix header files issues LKML-Reference: <1237009789.4387.2.camel@localhost.localdomain> Signed-off-by: Jaswinder Singh Rajput Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index 76139506c3e4..dccef5be0fc1 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -391,6 +391,9 @@ DECLARE_PER_CPU(union irq_stack_union, irq_stack_union); DECLARE_INIT_PER_CPU(irq_stack_union); DECLARE_PER_CPU(char *, irq_stack_ptr); +DECLARE_PER_CPU(unsigned int, irq_count); +extern unsigned long kernel_eflags; +extern asmlinkage void ignore_sysret(void); #else /* X86_64 */ #ifdef CONFIG_CC_STACKPROTECTOR DECLARE_PER_CPU(unsigned long, stack_canary); -- cgit v1.2.2 From 30e1e6d1af2b67558bccf322af2b3e0676b209ae Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Tue, 17 Mar 2009 14:50:34 +1030 Subject: cpumask: fix CONFIG_CPUMASK_OFFSTACK=y cpu hotunplug crash Impact: Fix cpu offline when CONFIG_MAXSMP=y Changeset bc9b83dd1f66402b870301c3c7117b9c1484abb4 "cpumask: convert c1e_mask in arch/x86/kernel/process.c to cpumask_var_t" contained a bug: c1e_mask is manipulated even if C1E isn't detected (and hence not allocated). This is simply fixed by checking for NULL (which gcc optimizes out anyway of CONFIG_CPUMASK_OFFSTACK=n, since it knows ce1_mask can never be NULL). In addition, fix a leak where select_idle_routine re-allocates (and re-clears) c1e_mask on every cpu init. Reported-by: Ingo Molnar Signed-off-by: Rusty Russell Cc: Mike Travis LKML-Reference: <200903171450.34549.rusty@rustcorp.com.au> Signed-off-by: Ingo Molnar --- arch/x86/include/asm/processor.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/x86/include/asm/processor.h') diff --git a/arch/x86/include/asm/processor.h b/arch/x86/include/asm/processor.h index d794d9483c56..9874dd98a29f 100644 --- a/arch/x86/include/asm/processor.h +++ b/arch/x86/include/asm/processor.h @@ -733,6 +733,7 @@ static inline void __sti_mwait(unsigned long eax, unsigned long ecx) extern void mwait_idle_with_hints(unsigned long eax, unsigned long ecx); extern void select_idle_routine(const struct cpuinfo_x86 *c); +extern void init_c1e_mask(void); extern unsigned long boot_option_idle_override; extern unsigned long idle_halt; -- cgit v1.2.2