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authorJohn David Anglin <dave.anglin@bell.net>2013-02-03 23:00:54 +0000
committerHelge Deller <deller@gmx.de>2013-02-20 22:49:29 +0100
commit6d2ddc2f9414d5ad0d3f014416020579ccce1baf (patch)
tree9417c7592d5cb1fe4d5bb4c93985ac16085d9de1
parent7633453978c54874849c5f40487ac9e14d43fc12 (diff)
downloadlinux-6d2ddc2f9414d5ad0d3f014416020579ccce1baf.tar.gz
parisc: fixes and cleanups in page cache flushing (2/4)
Implement clear_page_asm and copy_page_asm. These are optimized routines to clear and copy a page. I tested prefetch optimizations in clear_page_asm and copy_page_asm but didn't see any significant performance improvement on rp3440. I'm not sure if these are routines are significantly faster than memset and/or memcpy, but they are there for further performance evaluation. TLB purge operations on PA 1.X SMP machines are now serialized with the help of the new tlb_lock() and tlb_unlock() macros, since on some PA-RISC machines, TLB purges need to be serialized in software. Obviously, lock isn't needed in UP kernels. On PA 2.0 machines, there is a local TLB instruction which is much less disruptive to the memory subsystem. No lock is needed for local purge. Loops are also unrolled in flush_instruction_cache_local and flush_data_cache_local. The implementation of what used to be copy_user_page (now copy_user_page_asm) is now fixed. Additionally 64-bit support is now added. Read the preceding comment which I didn't change. I left the comment but it is now inaccurate. Signed-off-by: John David Anglin <dave.anglin@bell.net> Signed-off-by: Helge Deller <deller@gmx.de>
-rw-r--r--arch/parisc/kernel/pacache.S335
1 files changed, 290 insertions, 45 deletions
diff --git a/arch/parisc/kernel/pacache.S b/arch/parisc/kernel/pacache.S
index 5d7218ad885..312b48422a5 100644
--- a/arch/parisc/kernel/pacache.S
+++ b/arch/parisc/kernel/pacache.S
@@ -199,7 +199,6 @@ ENTRY(flush_instruction_cache_local)
.callinfo NO_CALLS
.entry
- mtsp %r0, %sr1
load32 cache_info, %r1
/* Flush Instruction Cache */
@@ -208,7 +207,8 @@ ENTRY(flush_instruction_cache_local)
LDREG ICACHE_STRIDE(%r1), %arg1
LDREG ICACHE_COUNT(%r1), %arg2
LDREG ICACHE_LOOP(%r1), %arg3
- rsm PSW_SM_I, %r22 /* No mmgt ops during loop*/
+ rsm PSW_SM_I, %r22 /* No mmgt ops during loop*/
+ mtsp %r0, %sr1
addib,COND(=) -1, %arg3, fioneloop /* Preadjust and test */
movb,<,n %arg3, %r31, fisync /* If loop < 0, do sync */
@@ -220,7 +220,33 @@ fimanyloop: /* Loop if LOOP >= 2 */
addib,COND(<=),n -1, %arg2, fisync /* Outer loop decr */
fioneloop: /* Loop if LOOP = 1 */
- addib,COND(>) -1, %arg2, fioneloop /* Outer loop count decr */
+ /* Some implementations may flush with a single fice instruction */
+ cmpib,COND(>>=),n 15, %arg2, fioneloop2
+
+fioneloop1:
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ fice,m %arg1(%sr1, %arg0)
+ addib,COND(>) -16, %arg2, fioneloop1
+ fice,m %arg1(%sr1, %arg0)
+
+ /* Check if done */
+ cmpb,COND(=),n %arg2, %r0, fisync /* Predict branch taken */
+
+fioneloop2:
+ addib,COND(>) -1, %arg2, fioneloop2 /* Outer loop count decr */
fice,m %arg1(%sr1, %arg0) /* Fice for one loop */
fisync:
@@ -240,8 +266,7 @@ ENTRY(flush_data_cache_local)
.callinfo NO_CALLS
.entry
- mtsp %r0, %sr1
- load32 cache_info, %r1
+ load32 cache_info, %r1
/* Flush Data Cache */
@@ -249,7 +274,8 @@ ENTRY(flush_data_cache_local)
LDREG DCACHE_STRIDE(%r1), %arg1
LDREG DCACHE_COUNT(%r1), %arg2
LDREG DCACHE_LOOP(%r1), %arg3
- rsm PSW_SM_I, %r22
+ rsm PSW_SM_I, %r22 /* No mmgt ops during loop*/
+ mtsp %r0, %sr1
addib,COND(=) -1, %arg3, fdoneloop /* Preadjust and test */
movb,<,n %arg3, %r31, fdsync /* If loop < 0, do sync */
@@ -261,7 +287,33 @@ fdmanyloop: /* Loop if LOOP >= 2 */
addib,COND(<=),n -1, %arg2, fdsync /* Outer loop decr */
fdoneloop: /* Loop if LOOP = 1 */
- addib,COND(>) -1, %arg2, fdoneloop /* Outer loop count decr */
+ /* Some implementations may flush with a single fdce instruction */
+ cmpib,COND(>>=),n 15, %arg2, fdoneloop2
+
+fdoneloop1:
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ fdce,m %arg1(%sr1, %arg0)
+ addib,COND(>) -16, %arg2, fdoneloop1
+ fdce,m %arg1(%sr1, %arg0)
+
+ /* Check if done */
+ cmpb,COND(=),n %arg2, %r0, fdsync /* Predict branch taken */
+
+fdoneloop2:
+ addib,COND(>) -1, %arg2, fdoneloop2 /* Outer loop count decr */
fdce,m %arg1(%sr1, %arg0) /* Fdce for one loop */
fdsync:
@@ -277,7 +329,104 @@ ENDPROC(flush_data_cache_local)
.align 16
-ENTRY(copy_user_page_asm)
+/* Macros to serialize TLB purge operations on SMP. */
+
+ .macro tlb_lock la,flags,tmp
+#ifdef CONFIG_SMP
+ ldil L%pa_tlb_lock,%r1
+ ldo R%pa_tlb_lock(%r1),\la
+ rsm PSW_SM_I,\flags
+1: LDCW 0(\la),\tmp
+ cmpib,<>,n 0,\tmp,3f
+2: ldw 0(\la),\tmp
+ cmpb,<> %r0,\tmp,1b
+ nop
+ b,n 2b
+3:
+#endif
+ .endm
+
+ .macro tlb_unlock la,flags,tmp
+#ifdef CONFIG_SMP
+ ldi 1,\tmp
+ stw \tmp,0(\la)
+ mtsm \flags
+#endif
+ .endm
+
+/* Clear page using kernel mapping. */
+
+ENTRY(clear_page_asm)
+ .proc
+ .callinfo NO_CALLS
+ .entry
+
+#ifdef CONFIG_64BIT
+
+ /* Unroll the loop. */
+ ldi (PAGE_SIZE / 128), %r1
+
+1:
+ std %r0, 0(%r26)
+ std %r0, 8(%r26)
+ std %r0, 16(%r26)
+ std %r0, 24(%r26)
+ std %r0, 32(%r26)
+ std %r0, 40(%r26)
+ std %r0, 48(%r26)
+ std %r0, 56(%r26)
+ std %r0, 64(%r26)
+ std %r0, 72(%r26)
+ std %r0, 80(%r26)
+ std %r0, 88(%r26)
+ std %r0, 96(%r26)
+ std %r0, 104(%r26)
+ std %r0, 112(%r26)
+ std %r0, 120(%r26)
+
+ /* Note reverse branch hint for addib is taken. */
+ addib,COND(>),n -1, %r1, 1b
+ ldo 128(%r26), %r26
+
+#else
+
+ /*
+ * Note that until (if) we start saving the full 64-bit register
+ * values on interrupt, we can't use std on a 32 bit kernel.
+ */
+ ldi (PAGE_SIZE / 64), %r1
+
+1:
+ stw %r0, 0(%r26)
+ stw %r0, 4(%r26)
+ stw %r0, 8(%r26)
+ stw %r0, 12(%r26)
+ stw %r0, 16(%r26)
+ stw %r0, 20(%r26)
+ stw %r0, 24(%r26)
+ stw %r0, 28(%r26)
+ stw %r0, 32(%r26)
+ stw %r0, 36(%r26)
+ stw %r0, 40(%r26)
+ stw %r0, 44(%r26)
+ stw %r0, 48(%r26)
+ stw %r0, 52(%r26)
+ stw %r0, 56(%r26)
+ stw %r0, 60(%r26)
+
+ addib,COND(>),n -1, %r1, 1b
+ ldo 64(%r26), %r26
+#endif
+ bv %r0(%r2)
+ nop
+ .exit
+
+ .procend
+ENDPROC(clear_page_asm)
+
+/* Copy page using kernel mapping. */
+
+ENTRY(copy_page_asm)
.proc
.callinfo NO_CALLS
.entry
@@ -285,18 +434,14 @@ ENTRY(copy_user_page_asm)
#ifdef CONFIG_64BIT
/* PA8x00 CPUs can consume 2 loads or 1 store per cycle.
* Unroll the loop by hand and arrange insn appropriately.
- * GCC probably can do this just as well.
+ * Prefetch doesn't improve performance on rp3440.
+ * GCC probably can do this just as well...
*/
- ldd 0(%r25), %r19
ldi (PAGE_SIZE / 128), %r1
- ldw 64(%r25), %r0 /* prefetch 1 cacheline ahead */
- ldw 128(%r25), %r0 /* prefetch 2 */
-
-1: ldd 8(%r25), %r20
- ldw 192(%r25), %r0 /* prefetch 3 */
- ldw 256(%r25), %r0 /* prefetch 4 */
+1: ldd 0(%r25), %r19
+ ldd 8(%r25), %r20
ldd 16(%r25), %r21
ldd 24(%r25), %r22
@@ -330,20 +475,16 @@ ENTRY(copy_user_page_asm)
ldd 112(%r25), %r21
ldd 120(%r25), %r22
+ ldo 128(%r25), %r25
std %r19, 96(%r26)
std %r20, 104(%r26)
- ldo 128(%r25), %r25
std %r21, 112(%r26)
std %r22, 120(%r26)
- ldo 128(%r26), %r26
- /* conditional branches nullify on forward taken branch, and on
- * non-taken backward branch. Note that .+4 is a backwards branch.
- * The ldd should only get executed if the branch is taken.
- */
- addib,COND(>),n -1, %r1, 1b /* bundle 10 */
- ldd 0(%r25), %r19 /* start next loads */
+ /* Note reverse branch hint for addib is taken. */
+ addib,COND(>),n -1, %r1, 1b
+ ldo 128(%r26), %r26
#else
@@ -399,7 +540,7 @@ ENTRY(copy_user_page_asm)
.exit
.procend
-ENDPROC(copy_user_page_asm)
+ENDPROC(copy_page_asm)
/*
* NOTE: Code in clear_user_page has a hard coded dependency on the
@@ -422,8 +563,6 @@ ENDPROC(copy_user_page_asm)
* %r23 physical page (shifted for tlb insert) of "from" translation
*/
-#if 0
-
/*
* We can't do this since copy_user_page is used to bring in
* file data that might have instructions. Since the data would
@@ -435,6 +574,7 @@ ENDPROC(copy_user_page_asm)
* use it if more information is passed into copy_user_page().
* Have to do some measurements to see if it is worthwhile to
* lobby for such a change.
+ *
*/
ENTRY(copy_user_page_asm)
@@ -442,16 +582,21 @@ ENTRY(copy_user_page_asm)
.callinfo NO_CALLS
.entry
+ /* Convert virtual `to' and `from' addresses to physical addresses.
+ Move `from' physical address to non shadowed register. */
ldil L%(__PAGE_OFFSET), %r1
sub %r26, %r1, %r26
- sub %r25, %r1, %r23 /* move physical addr into non shadowed reg */
+ sub %r25, %r1, %r23
ldil L%(TMPALIAS_MAP_START), %r28
/* FIXME for different page sizes != 4k */
#ifdef CONFIG_64BIT
- extrd,u %r26,56,32, %r26 /* convert phys addr to tlb insert format */
- extrd,u %r23,56,32, %r23 /* convert phys addr to tlb insert format */
- depd %r24,63,22, %r28 /* Form aliased virtual address 'to' */
+#if (TMPALIAS_MAP_START >= 0x80000000)
+ depdi 0, 31,32, %r28 /* clear any sign extension */
+#endif
+ extrd,u %r26,56,32, %r26 /* convert phys addr to tlb insert format */
+ extrd,u %r23,56,32, %r23 /* convert phys addr to tlb insert format */
+ depd %r24,63,22, %r28 /* Form aliased virtual address 'to' */
depdi 0, 63,12, %r28 /* Clear any offset bits */
copy %r28, %r29
depdi 1, 41,1, %r29 /* Form aliased virtual address 'from' */
@@ -466,10 +611,76 @@ ENTRY(copy_user_page_asm)
/* Purge any old translations */
+#ifdef CONFIG_PA20
+ pdtlb,l 0(%r28)
+ pdtlb,l 0(%r29)
+#else
+ tlb_lock %r20,%r21,%r22
pdtlb 0(%r28)
pdtlb 0(%r29)
+ tlb_unlock %r20,%r21,%r22
+#endif
+
+#ifdef CONFIG_64BIT
+ /* PA8x00 CPUs can consume 2 loads or 1 store per cycle.
+ * Unroll the loop by hand and arrange insn appropriately.
+ * GCC probably can do this just as well.
+ */
- ldi 64, %r1
+ ldd 0(%r29), %r19
+ ldi (PAGE_SIZE / 128), %r1
+
+1: ldd 8(%r29), %r20
+
+ ldd 16(%r29), %r21
+ ldd 24(%r29), %r22
+ std %r19, 0(%r28)
+ std %r20, 8(%r28)
+
+ ldd 32(%r29), %r19
+ ldd 40(%r29), %r20
+ std %r21, 16(%r28)
+ std %r22, 24(%r28)
+
+ ldd 48(%r29), %r21
+ ldd 56(%r29), %r22
+ std %r19, 32(%r28)
+ std %r20, 40(%r28)
+
+ ldd 64(%r29), %r19
+ ldd 72(%r29), %r20
+ std %r21, 48(%r28)
+ std %r22, 56(%r28)
+
+ ldd 80(%r29), %r21
+ ldd 88(%r29), %r22
+ std %r19, 64(%r28)
+ std %r20, 72(%r28)
+
+ ldd 96(%r29), %r19
+ ldd 104(%r29), %r20
+ std %r21, 80(%r28)
+ std %r22, 88(%r28)
+
+ ldd 112(%r29), %r21
+ ldd 120(%r29), %r22
+ std %r19, 96(%r28)
+ std %r20, 104(%r28)
+
+ ldo 128(%r29), %r29
+ std %r21, 112(%r28)
+ std %r22, 120(%r28)
+ ldo 128(%r28), %r28
+
+ /* conditional branches nullify on forward taken branch, and on
+ * non-taken backward branch. Note that .+4 is a backwards branch.
+ * The ldd should only get executed if the branch is taken.
+ */
+ addib,COND(>),n -1, %r1, 1b /* bundle 10 */
+ ldd 0(%r29), %r19 /* start next loads */
+
+#else
+ ldi (PAGE_SIZE / 64), %r1
/*
* This loop is optimized for PCXL/PCXL2 ldw/ldw and stw/stw
@@ -480,9 +691,7 @@ ENTRY(copy_user_page_asm)
* use ldd/std on a 32 bit kernel.
*/
-
-1:
- ldw 0(%r29), %r19
+1: ldw 0(%r29), %r19
ldw 4(%r29), %r20
ldw 8(%r29), %r21
ldw 12(%r29), %r22
@@ -515,8 +724,10 @@ ENTRY(copy_user_page_asm)
stw %r21, 56(%r28)
stw %r22, 60(%r28)
ldo 64(%r28), %r28
+
addib,COND(>) -1, %r1,1b
ldo 64(%r29), %r29
+#endif
bv %r0(%r2)
nop
@@ -524,9 +735,8 @@ ENTRY(copy_user_page_asm)
.procend
ENDPROC(copy_user_page_asm)
-#endif
-ENTRY(__clear_user_page_asm)
+ENTRY(clear_user_page_asm)
.proc
.callinfo NO_CALLS
.entry
@@ -550,7 +760,13 @@ ENTRY(__clear_user_page_asm)
/* Purge any old translation */
+#ifdef CONFIG_PA20
+ pdtlb,l 0(%r28)
+#else
+ tlb_lock %r20,%r21,%r22
pdtlb 0(%r28)
+ tlb_unlock %r20,%r21,%r22
+#endif
#ifdef CONFIG_64BIT
ldi (PAGE_SIZE / 128), %r1
@@ -580,8 +796,7 @@ ENTRY(__clear_user_page_asm)
#else /* ! CONFIG_64BIT */
ldi (PAGE_SIZE / 64), %r1
-1:
- stw %r0, 0(%r28)
+1: stw %r0, 0(%r28)
stw %r0, 4(%r28)
stw %r0, 8(%r28)
stw %r0, 12(%r28)
@@ -606,7 +821,7 @@ ENTRY(__clear_user_page_asm)
.exit
.procend
-ENDPROC(__clear_user_page_asm)
+ENDPROC(clear_user_page_asm)
ENTRY(flush_dcache_page_asm)
.proc
@@ -630,7 +845,13 @@ ENTRY(flush_dcache_page_asm)
/* Purge any old translation */
+#ifdef CONFIG_PA20
+ pdtlb,l 0(%r28)
+#else
+ tlb_lock %r20,%r21,%r22
pdtlb 0(%r28)
+ tlb_unlock %r20,%r21,%r22
+#endif
ldil L%dcache_stride, %r1
ldw R%dcache_stride(%r1), %r1
@@ -663,8 +884,17 @@ ENTRY(flush_dcache_page_asm)
fdc,m %r1(%r28)
sync
+
+#ifdef CONFIG_PA20
+ pdtlb,l 0(%r25)
+#else
+ tlb_lock %r20,%r21,%r22
+ pdtlb 0(%r25)
+ tlb_unlock %r20,%r21,%r22
+#endif
+
bv %r0(%r2)
- pdtlb (%r25)
+ nop
.exit
.procend
@@ -692,7 +922,13 @@ ENTRY(flush_icache_page_asm)
/* Purge any old translation */
- pitlb (%sr4,%r28)
+#ifdef CONFIG_PA20
+ pitlb,l %r0(%sr4,%r28)
+#else
+ tlb_lock %r20,%r21,%r22
+ pitlb (%sr4,%r28)
+ tlb_unlock %r20,%r21,%r22
+#endif
ldil L%icache_stride, %r1
ldw R%icache_stride(%r1), %r1
@@ -727,8 +963,17 @@ ENTRY(flush_icache_page_asm)
fic,m %r1(%sr4,%r28)
sync
+
+#ifdef CONFIG_PA20
+ pitlb,l %r0(%sr4,%r25)
+#else
+ tlb_lock %r20,%r21,%r22
+ pitlb (%sr4,%r25)
+ tlb_unlock %r20,%r21,%r22
+#endif
+
bv %r0(%r2)
- pitlb (%sr4,%r25)
+ nop
.exit
.procend
@@ -777,7 +1022,7 @@ ENTRY(flush_kernel_dcache_page_asm)
.procend
ENDPROC(flush_kernel_dcache_page_asm)
-ENTRY(purge_kernel_dcache_page)
+ENTRY(purge_kernel_dcache_page_asm)
.proc
.callinfo NO_CALLS
.entry
@@ -817,7 +1062,7 @@ ENTRY(purge_kernel_dcache_page)
.exit
.procend
-ENDPROC(purge_kernel_dcache_page)
+ENDPROC(purge_kernel_dcache_page_asm)
ENTRY(flush_user_dcache_range_asm)
.proc