[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH] linux-2.6.18/x86: make xor block handling uniform
Irrespective of the elimination of raw CR0 reads and writes, any of the methods requiring access to the floating point/XMM state still perform worse than the integer register based ones (at least as long as the virtual CR0.TS is set upon entry). Thus un-define XOR_SELECT_TEMPLATE in both 32- and 64-bit. On 64-bit additionally make the integer register based routines available for selection in the first place, and remove the duplicate code in the Xen specific header in favor of a small adjustment to the native one (using read_cr0()/clts()/write_cr0() instead of open coded accesses in the inline assembly). Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx> --- /dev/null +++ b/include/asm-i386/mach-xen/asm/xor.h @@ -0,0 +1,3 @@ +#include_next <asm/xor.h> + +#undef XOR_SELECT_TEMPLATE --- a/include/asm-x86_64/mach-xen/asm/xor.h +++ b/include/asm-x86_64/mach-xen/asm/xor.h @@ -1,328 +1,17 @@ -/* - * x86-64 changes / gcc fixes from Andi Kleen. - * Copyright 2002 Andi Kleen, SuSE Labs. - * - * This hasn't been optimized for the hammer yet, but there are likely - * no advantages to be gotten from x86-64 here anyways. - */ +#include_next <asm/xor.h> -typedef struct { unsigned long a,b; } __attribute__((aligned(16))) xmm_store_t; +#undef XOR_SELECT_TEMPLATE -/* Doesn't use gcc to save the XMM registers, because there is no easy way to - tell it to do a clts before the register saving. */ -#define XMMS_SAVE do { \ - preempt_disable(); \ - if (!(current_thread_info()->status & TS_USEDFPU)) \ - clts(); \ - __asm__ __volatile__ ( \ - "movups %%xmm0,(%1) ;\n\t" \ - "movups %%xmm1,0x10(%1) ;\n\t" \ - "movups %%xmm2,0x20(%1) ;\n\t" \ - "movups %%xmm3,0x30(%1) ;\n\t" \ - : "=&r" (cr0) \ - : "r" (xmm_save) \ - : "memory"); \ -} while(0) - -#define XMMS_RESTORE do { \ - asm volatile ( \ - "sfence ;\n\t" \ - "movups (%1),%%xmm0 ;\n\t" \ - "movups 0x10(%1),%%xmm1 ;\n\t" \ - "movups 0x20(%1),%%xmm2 ;\n\t" \ - "movups 0x30(%1),%%xmm3 ;\n\t" \ - : \ - : "r" (cr0), "r" (xmm_save) \ - : "memory"); \ - if (!(current_thread_info()->status & TS_USEDFPU)) \ - stts(); \ - preempt_enable(); \ -} while(0) - -#define OFFS(x) "16*("#x")" -#define PF_OFFS(x) "256+16*("#x")" -#define PF0(x) " prefetchnta "PF_OFFS(x)"(%[p1]) ;\n" -#define LD(x,y) " movaps "OFFS(x)"(%[p1]), %%xmm"#y" ;\n" -#define ST(x,y) " movaps %%xmm"#y", "OFFS(x)"(%[p1]) ;\n" -#define PF1(x) " prefetchnta "PF_OFFS(x)"(%[p2]) ;\n" -#define PF2(x) " prefetchnta "PF_OFFS(x)"(%[p3]) ;\n" -#define PF3(x) " prefetchnta "PF_OFFS(x)"(%[p4]) ;\n" -#define PF4(x) " prefetchnta "PF_OFFS(x)"(%[p5]) ;\n" -#define PF5(x) " prefetchnta "PF_OFFS(x)"(%[p6]) ;\n" -#define XO1(x,y) " xorps "OFFS(x)"(%[p2]), %%xmm"#y" ;\n" -#define XO2(x,y) " xorps "OFFS(x)"(%[p3]), %%xmm"#y" ;\n" -#define XO3(x,y) " xorps "OFFS(x)"(%[p4]), %%xmm"#y" ;\n" -#define XO4(x,y) " xorps "OFFS(x)"(%[p5]), %%xmm"#y" ;\n" -#define XO5(x,y) " xorps "OFFS(x)"(%[p6]), %%xmm"#y" ;\n" - - -static void -xor_sse_2(unsigned long bytes, unsigned long *p1, unsigned long *p2) -{ - unsigned int lines = bytes >> 8; - unsigned long cr0; - xmm_store_t xmm_save[4]; - - XMMS_SAVE; - - asm volatile ( -#undef BLOCK -#define BLOCK(i) \ - LD(i,0) \ - LD(i+1,1) \ - PF1(i) \ - PF1(i+2) \ - LD(i+2,2) \ - LD(i+3,3) \ - PF0(i+4) \ - PF0(i+6) \ - XO1(i,0) \ - XO1(i+1,1) \ - XO1(i+2,2) \ - XO1(i+3,3) \ - ST(i,0) \ - ST(i+1,1) \ - ST(i+2,2) \ - ST(i+3,3) \ - - - PF0(0) - PF0(2) - - " .align 32 ;\n" - " 1: ;\n" - - BLOCK(0) - BLOCK(4) - BLOCK(8) - BLOCK(12) - - " addq %[inc], %[p1] ;\n" - " addq %[inc], %[p2] ;\n" - " decl %[cnt] ; jnz 1b" - : [p1] "+r" (p1), [p2] "+r" (p2), [cnt] "+r" (lines) - : [inc] "r" (256UL) - : "memory"); - - XMMS_RESTORE; -} - -static void -xor_sse_3(unsigned long bytes, unsigned long *p1, unsigned long *p2, - unsigned long *p3) -{ - unsigned int lines = bytes >> 8; - xmm_store_t xmm_save[4]; - unsigned long cr0; - - XMMS_SAVE; - - __asm__ __volatile__ ( -#undef BLOCK -#define BLOCK(i) \ - PF1(i) \ - PF1(i+2) \ - LD(i,0) \ - LD(i+1,1) \ - LD(i+2,2) \ - LD(i+3,3) \ - PF2(i) \ - PF2(i+2) \ - PF0(i+4) \ - PF0(i+6) \ - XO1(i,0) \ - XO1(i+1,1) \ - XO1(i+2,2) \ - XO1(i+3,3) \ - XO2(i,0) \ - XO2(i+1,1) \ - XO2(i+2,2) \ - XO2(i+3,3) \ - ST(i,0) \ - ST(i+1,1) \ - ST(i+2,2) \ - ST(i+3,3) \ - - - PF0(0) - PF0(2) - - " .align 32 ;\n" - " 1: ;\n" - - BLOCK(0) - BLOCK(4) - BLOCK(8) - BLOCK(12) - - " addq %[inc], %[p1] ;\n" - " addq %[inc], %[p2] ;\n" - " addq %[inc], %[p3] ;\n" - " decl %[cnt] ; jnz 1b" - : [cnt] "+r" (lines), - [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3) - : [inc] "r" (256UL) - : "memory"); - XMMS_RESTORE; -} - -static void -xor_sse_4(unsigned long bytes, unsigned long *p1, unsigned long *p2, - unsigned long *p3, unsigned long *p4) -{ - unsigned int lines = bytes >> 8; - xmm_store_t xmm_save[4]; - unsigned long cr0; - - XMMS_SAVE; - - __asm__ __volatile__ ( -#undef BLOCK -#define BLOCK(i) \ - PF1(i) \ - PF1(i+2) \ - LD(i,0) \ - LD(i+1,1) \ - LD(i+2,2) \ - LD(i+3,3) \ - PF2(i) \ - PF2(i+2) \ - XO1(i,0) \ - XO1(i+1,1) \ - XO1(i+2,2) \ - XO1(i+3,3) \ - PF3(i) \ - PF3(i+2) \ - PF0(i+4) \ - PF0(i+6) \ - XO2(i,0) \ - XO2(i+1,1) \ - XO2(i+2,2) \ - XO2(i+3,3) \ - XO3(i,0) \ - XO3(i+1,1) \ - XO3(i+2,2) \ - XO3(i+3,3) \ - ST(i,0) \ - ST(i+1,1) \ - ST(i+2,2) \ - ST(i+3,3) \ - - - PF0(0) - PF0(2) - - " .align 32 ;\n" - " 1: ;\n" - - BLOCK(0) - BLOCK(4) - BLOCK(8) - BLOCK(12) - - " addq %[inc], %[p1] ;\n" - " addq %[inc], %[p2] ;\n" - " addq %[inc], %[p3] ;\n" - " addq %[inc], %[p4] ;\n" - " decl %[cnt] ; jnz 1b" - : [cnt] "+c" (lines), - [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3), [p4] "+r" (p4) - : [inc] "r" (256UL) - : "memory" ); - - XMMS_RESTORE; -} - -static void -xor_sse_5(unsigned long bytes, unsigned long *p1, unsigned long *p2, - unsigned long *p3, unsigned long *p4, unsigned long *p5) -{ - unsigned int lines = bytes >> 8; - xmm_store_t xmm_save[4]; - unsigned long cr0; - - XMMS_SAVE; - - __asm__ __volatile__ ( -#undef BLOCK -#define BLOCK(i) \ - PF1(i) \ - PF1(i+2) \ - LD(i,0) \ - LD(i+1,1) \ - LD(i+2,2) \ - LD(i+3,3) \ - PF2(i) \ - PF2(i+2) \ - XO1(i,0) \ - XO1(i+1,1) \ - XO1(i+2,2) \ - XO1(i+3,3) \ - PF3(i) \ - PF3(i+2) \ - XO2(i,0) \ - XO2(i+1,1) \ - XO2(i+2,2) \ - XO2(i+3,3) \ - PF4(i) \ - PF4(i+2) \ - PF0(i+4) \ - PF0(i+6) \ - XO3(i,0) \ - XO3(i+1,1) \ - XO3(i+2,2) \ - XO3(i+3,3) \ - XO4(i,0) \ - XO4(i+1,1) \ - XO4(i+2,2) \ - XO4(i+3,3) \ - ST(i,0) \ - ST(i+1,1) \ - ST(i+2,2) \ - ST(i+3,3) \ - - - PF0(0) - PF0(2) - - " .align 32 ;\n" - " 1: ;\n" - - BLOCK(0) - BLOCK(4) - BLOCK(8) - BLOCK(12) - - " addq %[inc], %[p1] ;\n" - " addq %[inc], %[p2] ;\n" - " addq %[inc], %[p3] ;\n" - " addq %[inc], %[p4] ;\n" - " addq %[inc], %[p5] ;\n" - " decl %[cnt] ; jnz 1b" - : [cnt] "+c" (lines), - [p1] "+r" (p1), [p2] "+r" (p2), [p3] "+r" (p3), [p4] "+r" (p4), - [p5] "+r" (p5) - : [inc] "r" (256UL) - : "memory"); - - XMMS_RESTORE; -} - -static struct xor_block_template xor_block_sse = { - .name = "generic_sse", - .do_2 = xor_sse_2, - .do_3 = xor_sse_3, - .do_4 = xor_sse_4, - .do_5 = xor_sse_5, -}; +/* Also try the generic routines. */ +#undef XOR_TRY_TEMPLATES +#include <asm-generic/xor.h> #undef XOR_TRY_TEMPLATES -#define XOR_TRY_TEMPLATES \ - do { \ +#define XOR_TRY_TEMPLATES \ + do { \ + xor_speed(&xor_block_8regs); \ + xor_speed(&xor_block_8regs_p); \ + xor_speed(&xor_block_32regs); \ + xor_speed(&xor_block_32regs_p); \ xor_speed(&xor_block_sse); \ } while (0) - -/* We force the use of the SSE xor block because it can write around L2. - We may also be able to load into the L1 only depending on how the cpu - deals with a load to a line that is being prefetched. */ -#define XOR_SELECT_TEMPLATE(FASTEST) (&xor_block_sse) --- a/include/asm-x86_64/xor.h +++ b/include/asm-x86_64/xor.h @@ -39,14 +39,14 @@ typedef struct { unsigned long a,b; } __ tell it to do a clts before the register saving. */ #define XMMS_SAVE do { \ preempt_disable(); \ + cr0 = read_cr0(); \ + clts(); \ asm volatile ( \ - "movq %%cr0,%0 ;\n\t" \ - "clts ;\n\t" \ "movups %%xmm0,(%1) ;\n\t" \ "movups %%xmm1,0x10(%1) ;\n\t" \ "movups %%xmm2,0x20(%1) ;\n\t" \ "movups %%xmm3,0x30(%1) ;\n\t" \ - : "=&r" (cr0) \ + : "+r" (cr0) \ : "r" (xmm_save) \ : "memory"); \ } while(0) @@ -58,10 +58,10 @@ typedef struct { unsigned long a,b; } __ "movups 0x10(%1),%%xmm1 ;\n\t" \ "movups 0x20(%1),%%xmm2 ;\n\t" \ "movups 0x30(%1),%%xmm3 ;\n\t" \ - "movq %0,%%cr0 ;\n\t" \ : \ : "r" (cr0), "r" (xmm_save) \ : "memory"); \ + write_cr0(cr0); \ preempt_enable(); \ } while(0) Attachment:
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