Merge git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile

Pull Tile arch updates from Chris Metcalf:
 "These changes bring in a bunch of new functionality that has been
  maintained internally at Tilera over the last year, plus other stray
  bits of work that I've taken into the tile tree from other folks.

  The changes include some PCI root complex work, interrupt-driven
  console support, support for performing fast-path unaligned data
  fixups by kernel-based JIT code generation, CONFIG_PREEMPT support,
  vDSO support for gettimeofday(), a serial driver for the tilegx
  on-chip UART, KGDB support, more optimized string routines, support
  for ftrace and kprobes, improved ASLR, and many bug fixes.

  We also remove support for the old TILE64 chip, which is no longer
  buildable"

* git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (85 commits)
  tile: refresh tile defconfig files
  tile: rework <asm/cmpxchg.h>
  tile PCI RC: make default consistent DMA mask 32-bit
  tile: add null check for kzalloc in tile/kernel/setup.c
  tile: make __write_once a synonym for __read_mostly
  tile: remove support for TILE64
  tile: use asm-generic/bitops/builtin-*.h
  tile: eliminate no-op "noatomichash" boot argument
  tile: use standard tile_bundle_bits type in traps.c
  tile: simplify code referencing hypervisor API addresses
  tile: change <asm/system.h> to <asm/switch_to.h> in comments
  tile: mark pcibios_init() as __init
  tile: check for correct compiler earlier in asm-offsets.c
  tile: use standard 'generic-y' model for <asm/hw_irq.h>
  tile: use asm-generic version of <asm/local64.h>
  tile PCI RC: add comment about "PCI hole" problem
  tile: remove DEBUG_EXTRA_FLAGS kernel config option
  tile: add virt_to_kpte() API and clean up and document behavior
  tile: support FRAME_POINTER
  tile: support reporting Tilera hypervisor statistics
  ...

1 files changed, 196 insertions, 68 deletions

diff --git a/arch/tile/lib/memcpy_64.c b/arch/tile/lib/memcpy_64.c
index c79b8e7..4815354 100644
--- a/arch/tile/lib/memcpy_64.c
+++ b/arch/tile/lib/memcpy_64.c
@@ -18,14 +18,17 @@
 /* EXPORT_SYMBOL() is in arch/tile/lib/exports.c since this should be asm. */
 
 /* Must be 8 bytes in size. */
-#define word_t uint64_t
+#define op_t uint64_t
 
-#if CHIP_L2_LINE_SIZE() != 64 && CHIP_L2_LINE_SIZE() != 128
-#error "Assumes 64 or 128 byte line size"
+/* Threshold value for when to enter the unrolled loops. */
+#define	OP_T_THRES	16
+
+#if CHIP_L2_LINE_SIZE() != 64
+#error "Assumes 64 byte line size"
 #endif
 
 /* How many cache lines ahead should we prefetch? */
-#define PREFETCH_LINES_AHEAD 3
+#define PREFETCH_LINES_AHEAD 4
 
 /*
  * Provide "base versions" of load and store for the normal code path.
@@ -51,15 +54,16 @@ void *memcpy(void *__restrict dstv, const void *__restrict srcv, size_t n)
  * macros to return a count of uncopied bytes due to mm fault.
  */
 #define RETVAL 0
-int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
+int __attribute__((optimize("omit-frame-pointer")))
+USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
 #endif
 {
 	char *__restrict dst1 = (char *)dstv;
 	const char *__restrict src1 = (const char *)srcv;
 	const char *__restrict src1_end;
 	const char *__restrict prefetch;
-	word_t *__restrict dst8;    /* 8-byte pointer to destination memory. */
-	word_t final; /* Final bytes to write to trailing word, if any */
+	op_t *__restrict dst8;    /* 8-byte pointer to destination memory. */
+	op_t final; /* Final bytes to write to trailing word, if any */
 	long i;
 
 	if (n < 16) {
@@ -79,104 +83,228 @@ int USERCOPY_FUNC(void *__restrict dstv, const void *__restrict srcv, size_t n)
 	for (i = 0; i < PREFETCH_LINES_AHEAD; i++) {
 		__insn_prefetch(prefetch);
 		prefetch += CHIP_L2_LINE_SIZE();
-		prefetch = (prefetch > src1_end) ? prefetch : src1;
+		prefetch = (prefetch < src1_end) ? prefetch : src1;
 	}
 
 	/* Copy bytes until dst is word-aligned. */
-	for (; (uintptr_t)dst1 & (sizeof(word_t) - 1); n--)
+	for (; (uintptr_t)dst1 & (sizeof(op_t) - 1); n--)
 		ST1(dst1++, LD1(src1++));
 
 	/* 8-byte pointer to destination memory. */
-	dst8 = (word_t *)dst1;
-
-	if (__builtin_expect((uintptr_t)src1 & (sizeof(word_t) - 1), 0)) {
-		/*
-		 * Misaligned copy.  Copy 8 bytes at a time, but don't
-		 * bother with other fanciness.
-		 *
-		 * TODO: Consider prefetching and using wh64 as well.
-		 */
-
-		/* Create an aligned src8. */
-		const word_t *__restrict src8 =
-			(const word_t *)((uintptr_t)src1 & -sizeof(word_t));
-		word_t b;
-
-		word_t a = LD8(src8++);
-		for (; n >= sizeof(word_t); n -= sizeof(word_t)) {
-			b = LD8(src8++);
-			a = __insn_dblalign(a, b, src1);
-			ST8(dst8++, a);
-			a = b;
+	dst8 = (op_t *)dst1;
+
+	if (__builtin_expect((uintptr_t)src1 & (sizeof(op_t) - 1), 0)) {
+		/* Unaligned copy. */
+
+		op_t  tmp0 = 0, tmp1 = 0, tmp2, tmp3;
+		const op_t *src8 = (const op_t *) ((uintptr_t)src1 &
+						   -sizeof(op_t));
+		const void *srci = (void *)src1;
+		int m;
+
+		m = (CHIP_L2_LINE_SIZE() << 2) -
+			(((uintptr_t)dst8) & ((CHIP_L2_LINE_SIZE() << 2) - 1));
+		m = (n < m) ? n : m;
+		m /= sizeof(op_t);
+
+		/* Copy until 'dst' is cache-line-aligned. */
+		n -= (sizeof(op_t) * m);
+
+		switch (m % 4) {
+		case 0:
+			if (__builtin_expect(!m, 0))
+				goto _M0;
+			tmp1 = LD8(src8++);
+			tmp2 = LD8(src8++);
+			goto _8B3;
+		case 2:
+			m += 2;
+			tmp3 = LD8(src8++);
+			tmp0 = LD8(src8++);
+			goto _8B1;
+		case 3:
+			m += 1;
+			tmp2 = LD8(src8++);
+			tmp3 = LD8(src8++);
+			goto _8B2;
+		case 1:
+			m--;
+			tmp0 = LD8(src8++);
+			tmp1 = LD8(src8++);
+			if (__builtin_expect(!m, 0))
+				goto _8B0;
+		}
+
+		do {
+			tmp2 = LD8(src8++);
+			tmp0 =  __insn_dblalign(tmp0, tmp1, srci);
+			ST8(dst8++, tmp0);
+_8B3:
+			tmp3 = LD8(src8++);
+			tmp1 = __insn_dblalign(tmp1, tmp2, srci);
+			ST8(dst8++, tmp1);
+_8B2:
+			tmp0 = LD8(src8++);
+			tmp2 = __insn_dblalign(tmp2, tmp3, srci);
+			ST8(dst8++, tmp2);
+_8B1:
+			tmp1 = LD8(src8++);
+			tmp3 = __insn_dblalign(tmp3, tmp0, srci);
+			ST8(dst8++, tmp3);
+			m -= 4;
+		} while (m);
+
+_8B0:
+		tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+		ST8(dst8++, tmp0);
+		src8--;
+
+_M0:
+		if (__builtin_expect(n >= CHIP_L2_LINE_SIZE(), 0)) {
+			op_t tmp4, tmp5, tmp6, tmp7, tmp8;
+
+			prefetch = ((const char *)src8) +
+				CHIP_L2_LINE_SIZE() * PREFETCH_LINES_AHEAD;
+
+			for (tmp0 = LD8(src8++); n >= CHIP_L2_LINE_SIZE();
+			     n -= CHIP_L2_LINE_SIZE()) {
+				/* Prefetch and advance to next line to
+				   prefetch, but don't go past the end.  */
+				__insn_prefetch(prefetch);
+
+				/* Make sure prefetch got scheduled
+				   earlier.  */
+				__asm__ ("" : : : "memory");
+
+				prefetch += CHIP_L2_LINE_SIZE();
+				prefetch = (prefetch < src1_end) ? prefetch :
+					(const char *) src8;
+
+				tmp1 = LD8(src8++);
+				tmp2 = LD8(src8++);
+				tmp3 = LD8(src8++);
+				tmp4 = LD8(src8++);
+				tmp5 = LD8(src8++);
+				tmp6 = LD8(src8++);
+				tmp7 = LD8(src8++);
+				tmp8 = LD8(src8++);
+
+				tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+				tmp1 = __insn_dblalign(tmp1, tmp2, srci);
+				tmp2 = __insn_dblalign(tmp2, tmp3, srci);
+				tmp3 = __insn_dblalign(tmp3, tmp4, srci);
+				tmp4 = __insn_dblalign(tmp4, tmp5, srci);
+				tmp5 = __insn_dblalign(tmp5, tmp6, srci);
+				tmp6 = __insn_dblalign(tmp6, tmp7, srci);
+				tmp7 = __insn_dblalign(tmp7, tmp8, srci);
+
+				__insn_wh64(dst8);
+
+				ST8(dst8++, tmp0);
+				ST8(dst8++, tmp1);
+				ST8(dst8++, tmp2);
+				ST8(dst8++, tmp3);
+				ST8(dst8++, tmp4);
+				ST8(dst8++, tmp5);
+				ST8(dst8++, tmp6);
+				ST8(dst8++, tmp7);
+
+				tmp0 = tmp8;
+			}
+			src8--;
+		}
+
+		/* Copy the rest 8-byte chunks. */
+		if (n >= sizeof(op_t)) {
+			tmp0 = LD8(src8++);
+			for (; n >= sizeof(op_t); n -= sizeof(op_t)) {
+				tmp1 = LD8(src8++);
+				tmp0 = __insn_dblalign(tmp0, tmp1, srci);
+				ST8(dst8++, tmp0);
+				tmp0 = tmp1;
+			}
+			src8--;
 		}
 
 		if (n == 0)
 			return RETVAL;
 
-		b = ((const char *)src8 <= src1_end) ? *src8 : 0;
+		tmp0 = LD8(src8++);
+		tmp1 = ((const char *)src8 <= src1_end)
+			? LD8((op_t *)src8) : 0;
+		final = __insn_dblalign(tmp0, tmp1, srci);
 
-		/*
-		 * Final source bytes to write to trailing partial
-		 * word, if any.
-		 */
-		final = __insn_dblalign(a, b, src1);
 	} else {
 		/* Aligned copy. */
 
-		const word_t* __restrict src8 = (const word_t *)src1;
+		const op_t *__restrict src8 = (const op_t *)src1;
 
 		/* src8 and dst8 are both word-aligned. */
 		if (n >= CHIP_L2_LINE_SIZE()) {
 			/* Copy until 'dst' is cache-line-aligned. */
 			for (; (uintptr_t)dst8 & (CHIP_L2_LINE_SIZE() - 1);
-			     n -= sizeof(word_t))
+			     n -= sizeof(op_t))
 				ST8(dst8++, LD8(src8++));
 
 			for (; n >= CHIP_L2_LINE_SIZE(); ) {
-				__insn_wh64(dst8);
+				op_t tmp0, tmp1, tmp2, tmp3;
+				op_t tmp4, tmp5, tmp6, tmp7;
 
 				/*
 				 * Prefetch and advance to next line
-				 * to prefetch, but don't go past the end
+				 * to prefetch, but don't go past the
+				 * end.
 				 */
 				__insn_prefetch(prefetch);
+
+				/* Make sure prefetch got scheduled
+				   earlier.  */
+				__asm__ ("" : : : "memory");
+
 				prefetch += CHIP_L2_LINE_SIZE();
-				prefetch = (prefetch > src1_end) ? prefetch :
+				prefetch = (prefetch < src1_end) ? prefetch :
 					(const char *)src8;
 
 				/*
-				 * Copy an entire cache line.  Manually
-				 * unrolled to avoid idiosyncracies of
-				 * compiler unrolling.
+				 * Do all the loads before wh64.  This
+				 * is necessary if [src8, src8+7] and
+				 * [dst8, dst8+7] share the same cache
+				 * line and dst8 <= src8, as can be
+				 * the case when called from memmove,
+				 * or with code tested on x86 whose
+				 * memcpy always works with forward
+				 * copies.
 				 */
-#define COPY_WORD(offset) ({ ST8(dst8+offset, LD8(src8+offset)); n -= 8; })
-				COPY_WORD(0);
-				COPY_WORD(1);
-				COPY_WORD(2);
-				COPY_WORD(3);
-				COPY_WORD(4);
-				COPY_WORD(5);
-				COPY_WORD(6);
-				COPY_WORD(7);
-#if CHIP_L2_LINE_SIZE() == 128
-				COPY_WORD(8);
-				COPY_WORD(9);
-				COPY_WORD(10);
-				COPY_WORD(11);
-				COPY_WORD(12);
-				COPY_WORD(13);
-				COPY_WORD(14);
-				COPY_WORD(15);
-#elif CHIP_L2_LINE_SIZE() != 64
-# error Fix code that assumes particular L2 cache line sizes
-#endif
+				tmp0 = LD8(src8++);
+				tmp1 = LD8(src8++);
+				tmp2 = LD8(src8++);
+				tmp3 = LD8(src8++);
+				tmp4 = LD8(src8++);
+				tmp5 = LD8(src8++);
+				tmp6 = LD8(src8++);
+				tmp7 = LD8(src8++);
+
+				/* wh64 and wait for tmp7 load completion. */
+				__asm__ ("move %0, %0; wh64 %1\n"
+					 : : "r"(tmp7), "r"(dst8));
 
-				dst8 += CHIP_L2_LINE_SIZE() / sizeof(word_t);
-				src8 += CHIP_L2_LINE_SIZE() / sizeof(word_t);
+				ST8(dst8++, tmp0);
+				ST8(dst8++, tmp1);
+				ST8(dst8++, tmp2);
+				ST8(dst8++, tmp3);
+				ST8(dst8++, tmp4);
+				ST8(dst8++, tmp5);
+				ST8(dst8++, tmp6);
+				ST8(dst8++, tmp7);
+
+				n -= CHIP_L2_LINE_SIZE();
 			}
+#if CHIP_L2_LINE_SIZE() != 64
+# error "Fix code that assumes particular L2 cache line size."
+#endif
 		}
 
-		for (; n >= sizeof(word_t); n -= sizeof(word_t))
+		for (; n >= sizeof(op_t); n -= sizeof(op_t))
 			ST8(dst8++, LD8(src8++));
 
 		if (__builtin_expect(n == 0, 1))