selftests/powerpc: Move core_busy_loop() into asm

There is at least one bug in core_busy_loop(), we use r0, but it's
not in the clobber list. We were getting away with this it seems but
that was luck.

It's also fishy to be touching the stack, even if we do it below the
stack pointer. It seems we get away with it, but looking at the
generated code that may just be luck.

So move it into assembler, do all the stack handling by hand. We create
a stack frame to save the non-volatiles in, so we can muck around with
them.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

diff --git a/tools/testing/selftests/powerpc/pmu/ebb/Makefile b/tools/testing/selftests/powerpc/pmu/ebb/Makefile
index edbba2affc2c4bb01612636ed6e5fc8c5cc0579b..251447eafe49ea38d5e4c8f4755dc052c40943fe 100644 (file)
--- a/tools/testing/selftests/powerpc/pmu/ebb/Makefile
+++ b/tools/testing/selftests/powerpc/pmu/ebb/Makefile
@@ -17,7 +17,7 @@ PROGS := reg_access_test event_attributes_test cycles_test    \
 
 all: $(PROGS)
 
-$(PROGS): ../../harness.c ../event.c ../lib.c ebb.c ebb_handler.S trace.c
+$(PROGS): ../../harness.c ../event.c ../lib.c ebb.c ebb_handler.S trace.c busy_loop.S
 
 instruction_count_test: ../loop.S
 

diff --git a/tools/testing/selftests/powerpc/pmu/ebb/busy_loop.S b/tools/testing/selftests/powerpc/pmu/ebb/busy_loop.S
new file mode 100644 (file)
index 0000000..c7e4093
--- /dev/null
+++ b/tools/testing/selftests/powerpc/pmu/ebb/busy_loop.S
@@ -0,0 +1,271 @@
+/*
+ * Copyright 2014, Michael Ellerman, IBM Corp.
+ * Licensed under GPLv2.
+ */
+
+#include <ppc-asm.h>
+
+       .text
+
+FUNC_START(core_busy_loop)
+       stdu    %r1, -168(%r1)
+       std     r14, 160(%r1)
+       std     r15, 152(%r1)
+       std     r16, 144(%r1)
+       std     r17, 136(%r1)
+       std     r18, 128(%r1)
+       std     r19, 120(%r1)
+       std     r20, 112(%r1)
+       std     r21, 104(%r1)
+       std     r22, 96(%r1)
+       std     r23, 88(%r1)
+       std     r24, 80(%r1)
+       std     r25, 72(%r1)
+       std     r26, 64(%r1)
+       std     r27, 56(%r1)
+       std     r28, 48(%r1)
+       std     r29, 40(%r1)
+       std     r30, 32(%r1)
+       std     r31, 24(%r1)
+
+       li       r3, 0x3030
+       std      r3, -96(%r1)
+       li       r4, 0x4040
+       std      r4, -104(%r1)
+       li       r5, 0x5050
+       std      r5, -112(%r1)
+       li       r6, 0x6060
+       std      r6, -120(%r1)
+       li       r7, 0x7070
+       std      r7, -128(%r1)
+       li       r8, 0x0808
+       std      r8, -136(%r1)
+       li       r9, 0x0909
+       std      r9, -144(%r1)
+       li      r10, 0x1010
+       std     r10, -152(%r1)
+       li      r11, 0x1111
+       std     r11, -160(%r1)
+       li      r14, 0x1414
+       std     r14, -168(%r1)
+       li      r15, 0x1515
+       std     r15, -176(%r1)
+       li      r16, 0x1616
+       std     r16, -184(%r1)
+       li      r17, 0x1717
+       std     r17, -192(%r1)
+       li      r18, 0x1818
+       std     r18, -200(%r1)
+       li      r19, 0x1919
+       std     r19, -208(%r1)
+       li      r20, 0x2020
+       std     r20, -216(%r1)
+       li      r21, 0x2121
+       std     r21, -224(%r1)
+       li      r22, 0x2222
+       std     r22, -232(%r1)
+       li      r23, 0x2323
+       std     r23, -240(%r1)
+       li      r24, 0x2424
+       std     r24, -248(%r1)
+       li      r25, 0x2525
+       std     r25, -256(%r1)
+       li      r26, 0x2626
+       std     r26, -264(%r1)
+       li      r27, 0x2727
+       std     r27, -272(%r1)
+       li      r28, 0x2828
+       std     r28, -280(%r1)
+       li      r29, 0x2929
+       std     r29, -288(%r1)
+       li      r30, 0x3030
+       li      r31, 0x3131
+
+       li      r3, 0
+0:     addi    r3, r3, 1
+       cmpwi   r3, 100
+       blt     0b
+
+       /* Return 1 (fail) unless we get through all the checks */
+       li      r3, 1
+
+       /* Check none of our registers have been corrupted */
+       cmpwi   r4,  0x4040
+       bne     1f
+       cmpwi   r5,  0x5050
+       bne     1f
+       cmpwi   r6,  0x6060
+       bne     1f
+       cmpwi   r7,  0x7070
+       bne     1f
+       cmpwi   r8,  0x0808
+       bne     1f
+       cmpwi   r9,  0x0909
+       bne     1f
+       cmpwi   r10, 0x1010
+       bne     1f
+       cmpwi   r11, 0x1111
+       bne     1f
+       cmpwi   r14, 0x1414
+       bne     1f
+       cmpwi   r15, 0x1515
+       bne     1f
+       cmpwi   r16, 0x1616
+       bne     1f
+       cmpwi   r17, 0x1717
+       bne     1f
+       cmpwi   r18, 0x1818
+       bne     1f
+       cmpwi   r19, 0x1919
+       bne     1f
+       cmpwi   r20, 0x2020
+       bne     1f
+       cmpwi   r21, 0x2121
+       bne     1f
+       cmpwi   r22, 0x2222
+       bne     1f
+       cmpwi   r23, 0x2323
+       bne     1f
+       cmpwi   r24, 0x2424
+       bne     1f
+       cmpwi   r25, 0x2525
+       bne     1f
+       cmpwi   r26, 0x2626
+       bne     1f
+       cmpwi   r27, 0x2727
+       bne     1f
+       cmpwi   r28, 0x2828
+       bne     1f
+       cmpwi   r29, 0x2929
+       bne     1f
+       cmpwi   r30, 0x3030
+       bne     1f
+       cmpwi   r31, 0x3131
+       bne     1f
+
+       /* Load junk into all our registers before we reload them from the stack. */
+       li      r3,  0xde
+       li      r4,  0xad
+       li      r5,  0xbe
+       li      r6,  0xef
+       li      r7,  0xde
+       li      r8,  0xad
+       li      r9,  0xbe
+       li      r10, 0xef
+       li      r11, 0xde
+       li      r14, 0xad
+       li      r15, 0xbe
+       li      r16, 0xef
+       li      r17, 0xde
+       li      r18, 0xad
+       li      r19, 0xbe
+       li      r20, 0xef
+       li      r21, 0xde
+       li      r22, 0xad
+       li      r23, 0xbe
+       li      r24, 0xef
+       li      r25, 0xde
+       li      r26, 0xad
+       li      r27, 0xbe
+       li      r28, 0xef
+       li      r29, 0xdd
+
+       ld      r3,     -96(%r1)
+       cmpwi   r3,  0x3030
+       bne     1f
+       ld      r4,     -104(%r1)
+       cmpwi   r4,  0x4040
+       bne     1f
+       ld      r5,     -112(%r1)
+       cmpwi   r5,  0x5050
+       bne     1f
+       ld      r6,     -120(%r1)
+       cmpwi   r6,  0x6060
+       bne     1f
+       ld      r7,     -128(%r1)
+       cmpwi   r7,  0x7070
+       bne     1f
+       ld      r8,     -136(%r1)
+       cmpwi   r8,  0x0808
+       bne     1f
+       ld      r9,     -144(%r1)
+       cmpwi   r9,  0x0909
+       bne     1f
+       ld      r10, -152(%r1)
+       cmpwi   r10, 0x1010
+       bne     1f
+       ld      r11, -160(%r1)
+       cmpwi   r11, 0x1111
+       bne     1f
+       ld      r14, -168(%r1)
+       cmpwi   r14, 0x1414
+       bne     1f
+       ld      r15, -176(%r1)
+       cmpwi   r15, 0x1515
+       bne     1f
+       ld      r16, -184(%r1)
+       cmpwi   r16, 0x1616
+       bne     1f
+       ld      r17, -192(%r1)
+       cmpwi   r17, 0x1717
+       bne     1f
+       ld      r18, -200(%r1)
+       cmpwi   r18, 0x1818
+       bne     1f
+       ld      r19, -208(%r1)
+       cmpwi   r19, 0x1919
+       bne     1f
+       ld      r20, -216(%r1)
+       cmpwi   r20, 0x2020
+       bne     1f
+       ld      r21, -224(%r1)
+       cmpwi   r21, 0x2121
+       bne     1f
+       ld      r22, -232(%r1)
+       cmpwi   r22, 0x2222
+       bne     1f
+       ld      r23, -240(%r1)
+       cmpwi   r23, 0x2323
+       bne     1f
+       ld      r24, -248(%r1)
+       cmpwi   r24, 0x2424
+       bne     1f
+       ld      r25, -256(%r1)
+       cmpwi   r25, 0x2525
+       bne     1f
+       ld      r26, -264(%r1)
+       cmpwi   r26, 0x2626
+       bne     1f
+       ld      r27, -272(%r1)
+       cmpwi   r27, 0x2727
+       bne     1f
+       ld      r28, -280(%r1)
+       cmpwi   r28, 0x2828
+       bne     1f
+       ld      r29, -288(%r1)
+       cmpwi   r29, 0x2929
+       bne     1f
+
+       /* Load 0 (success) to return */
+       li      r3, 0
+
+1:     ld      r14, 160(%r1)
+       ld      r15, 152(%r1)
+       ld      r16, 144(%r1)
+       ld      r17, 136(%r1)
+       ld      r18, 128(%r1)
+       ld      r19, 120(%r1)
+       ld      r20, 112(%r1)
+       ld      r21, 104(%r1)
+       ld      r22, 96(%r1)
+       ld      r23, 88(%r1)
+       ld      r24, 80(%r1)
+       ld      r25, 72(%r1)
+       ld      r26, 64(%r1)
+       ld      r27, 56(%r1)
+       ld      r28, 48(%r1)
+       ld      r29, 40(%r1)
+       ld      r30, 32(%r1)
+       ld      r31, 24(%r1)
+       addi    %r1, %r1, 168
+       blr

diff --git a/tools/testing/selftests/powerpc/pmu/ebb/ebb.c b/tools/testing/selftests/powerpc/pmu/ebb/ebb.c
index 1b46be94b64c5cd82e48800225185f16db1f7767..b7ee607c0fca11b46f0e10939d2b83dad7ac0f86 100644 (file)
--- a/tools/testing/selftests/powerpc/pmu/ebb/ebb.c
+++ b/tools/testing/selftests/powerpc/pmu/ebb/ebb.c
@@ -335,257 +335,6 @@ void event_leader_ebb_init(struct event *e)
        e->attr.pinned = 1;
 }
 
-int core_busy_loop(void)
-{
-       int rc;
-
-       asm volatile (
-               "li  3,  0x3030\n"
-               "std 3,  -96(1)\n"
-               "li  4,  0x4040\n"
-               "std 4,  -104(1)\n"
-               "li  5,  0x5050\n"
-               "std 5,  -112(1)\n"
-               "li  6,  0x6060\n"
-               "std 6,  -120(1)\n"
-               "li  7,  0x7070\n"
-               "std 7,  -128(1)\n"
-               "li  8,  0x0808\n"
-               "std 8,  -136(1)\n"
-               "li  9,  0x0909\n"
-               "std 9,  -144(1)\n"
-               "li  10, 0x1010\n"
-               "std 10, -152(1)\n"
-               "li  11, 0x1111\n"
-               "std 11, -160(1)\n"
-               "li  14, 0x1414\n"
-               "std 14, -168(1)\n"
-               "li  15, 0x1515\n"
-               "std 15, -176(1)\n"
-               "li  16, 0x1616\n"
-               "std 16, -184(1)\n"
-               "li  17, 0x1717\n"
-               "std 17, -192(1)\n"
-               "li  18, 0x1818\n"
-               "std 18, -200(1)\n"
-               "li  19, 0x1919\n"
-               "std 19, -208(1)\n"
-               "li  20, 0x2020\n"
-               "std 20, -216(1)\n"
-               "li  21, 0x2121\n"
-               "std 21, -224(1)\n"
-               "li  22, 0x2222\n"
-               "std 22, -232(1)\n"
-               "li  23, 0x2323\n"
-               "std 23, -240(1)\n"
-               "li  24, 0x2424\n"
-               "std 24, -248(1)\n"
-               "li  25, 0x2525\n"
-               "std 25, -256(1)\n"
-               "li  26, 0x2626\n"
-               "std 26, -264(1)\n"
-               "li  27, 0x2727\n"
-               "std 27, -272(1)\n"
-               "li  28, 0x2828\n"
-               "std 28, -280(1)\n"
-               "li  29, 0x2929\n"
-               "std 29, -288(1)\n"
-               "li  30, 0x3030\n"
-               "li  31, 0x3131\n"
-
-               "li    3,  0\n"
-               "0: "
-               "addi  3, 3, 1\n"
-               "cmpwi 3, 100\n"
-               "blt   0b\n"
-
-               /* Return 1 (fail) unless we get through all the checks */
-               "li     0, 1\n"
-
-               /* Check none of our registers have been corrupted */
-               "cmpwi  4,  0x4040\n"
-               "bne    1f\n"
-               "cmpwi  5,  0x5050\n"
-               "bne    1f\n"
-               "cmpwi  6,  0x6060\n"
-               "bne    1f\n"
-               "cmpwi  7,  0x7070\n"
-               "bne    1f\n"
-               "cmpwi  8,  0x0808\n"
-               "bne    1f\n"
-               "cmpwi  9,  0x0909\n"
-               "bne    1f\n"
-               "cmpwi  10, 0x1010\n"
-               "bne    1f\n"
-               "cmpwi  11, 0x1111\n"
-               "bne    1f\n"
-               "cmpwi  14, 0x1414\n"
-               "bne    1f\n"
-               "cmpwi  15, 0x1515\n"
-               "bne    1f\n"
-               "cmpwi  16, 0x1616\n"
-               "bne    1f\n"
-               "cmpwi  17, 0x1717\n"
-               "bne    1f\n"
-               "cmpwi  18, 0x1818\n"
-               "bne    1f\n"
-               "cmpwi  19, 0x1919\n"
-               "bne    1f\n"
-               "cmpwi  20, 0x2020\n"
-               "bne    1f\n"
-               "cmpwi  21, 0x2121\n"
-               "bne    1f\n"
-               "cmpwi  22, 0x2222\n"
-               "bne    1f\n"
-               "cmpwi  23, 0x2323\n"
-               "bne    1f\n"
-               "cmpwi  24, 0x2424\n"
-               "bne    1f\n"
-               "cmpwi  25, 0x2525\n"
-               "bne    1f\n"
-               "cmpwi  26, 0x2626\n"
-               "bne    1f\n"
-               "cmpwi  27, 0x2727\n"
-               "bne    1f\n"
-               "cmpwi  28, 0x2828\n"
-               "bne    1f\n"
-               "cmpwi  29, 0x2929\n"
-               "bne    1f\n"
-               "cmpwi  30, 0x3030\n"
-               "bne    1f\n"
-               "cmpwi  31, 0x3131\n"
-               "bne    1f\n"
-
-               /* Load junk into all our registers before we reload them from the stack. */
-               "li  3,  0xde\n"
-               "li  4,  0xad\n"
-               "li  5,  0xbe\n"
-               "li  6,  0xef\n"
-               "li  7,  0xde\n"
-               "li  8,  0xad\n"
-               "li  9,  0xbe\n"
-               "li  10, 0xef\n"
-               "li  11, 0xde\n"
-               "li  14, 0xad\n"
-               "li  15, 0xbe\n"
-               "li  16, 0xef\n"
-               "li  17, 0xde\n"
-               "li  18, 0xad\n"
-               "li  19, 0xbe\n"
-               "li  20, 0xef\n"
-               "li  21, 0xde\n"
-               "li  22, 0xad\n"
-               "li  23, 0xbe\n"
-               "li  24, 0xef\n"
-               "li  25, 0xde\n"
-               "li  26, 0xad\n"
-               "li  27, 0xbe\n"
-               "li  28, 0xef\n"
-               "li  29, 0xdd\n"
-
-               "ld     3,  -96(1)\n"
-               "cmpwi  3,  0x3030\n"
-               "bne    1f\n"
-               "ld     4,  -104(1)\n"
-               "cmpwi  4,  0x4040\n"
-               "bne    1f\n"
-               "ld     5,  -112(1)\n"
-               "cmpwi  5,  0x5050\n"
-               "bne    1f\n"
-               "ld     6,  -120(1)\n"
-               "cmpwi  6,  0x6060\n"
-               "bne    1f\n"
-               "ld     7,  -128(1)\n"
-               "cmpwi  7,  0x7070\n"
-               "bne    1f\n"
-               "ld     8,  -136(1)\n"
-               "cmpwi  8,  0x0808\n"
-               "bne    1f\n"
-               "ld     9,  -144(1)\n"
-               "cmpwi  9,  0x0909\n"
-               "bne    1f\n"
-               "ld     10, -152(1)\n"
-               "cmpwi  10, 0x1010\n"
-               "bne    1f\n"
-               "ld     11, -160(1)\n"
-               "cmpwi  11, 0x1111\n"
-               "bne    1f\n"
-               "ld     14, -168(1)\n"
-               "cmpwi  14, 0x1414\n"
-               "bne    1f\n"
-               "ld     15, -176(1)\n"
-               "cmpwi  15, 0x1515\n"
-               "bne    1f\n"
-               "ld     16, -184(1)\n"
-               "cmpwi  16, 0x1616\n"
-               "bne    1f\n"
-               "ld     17, -192(1)\n"
-               "cmpwi  17, 0x1717\n"
-               "bne    1f\n"
-               "ld     18, -200(1)\n"
-               "cmpwi  18, 0x1818\n"
-               "bne    1f\n"
-               "ld     19, -208(1)\n"
-               "cmpwi  19, 0x1919\n"
-               "bne    1f\n"
-               "ld     20, -216(1)\n"
-               "cmpwi  20, 0x2020\n"
-               "bne    1f\n"
-               "ld     21, -224(1)\n"
-               "cmpwi  21, 0x2121\n"
-               "bne    1f\n"
-               "ld     22, -232(1)\n"
-               "cmpwi  22, 0x2222\n"
-               "bne    1f\n"
-               "ld     23, -240(1)\n"
-               "cmpwi  23, 0x2323\n"
-               "bne    1f\n"
-               "ld     24, -248(1)\n"
-               "cmpwi  24, 0x2424\n"
-               "bne    1f\n"
-               "ld     25, -256(1)\n"
-               "cmpwi  25, 0x2525\n"
-               "bne    1f\n"
-               "ld     26, -264(1)\n"
-               "cmpwi  26, 0x2626\n"
-               "bne    1f\n"
-               "ld     27, -272(1)\n"
-               "cmpwi  27, 0x2727\n"
-               "bne    1f\n"
-               "ld     28, -280(1)\n"
-               "cmpwi  28, 0x2828\n"
-               "bne    1f\n"
-               "ld     29, -288(1)\n"
-               "cmpwi  29, 0x2929\n"
-               "bne    1f\n"
-
-               /* Load 0 (success) to return */
-               "li     0, 0\n"
-
-               "1:     mr %0, 0\n"
-
-               : "=r" (rc)
-               : /* no inputs */
-               : "3", "4", "5", "6", "7", "8", "9", "10", "11", "14",
-                 "15", "16", "17", "18", "19", "20", "21", "22", "23",
-                  "24", "25", "26", "27", "28", "29", "30", "31",
-                  "memory"
-       );
-
-       return rc;
-}
-
-int core_busy_loop_with_freeze(void)
-{
-       int rc;
-
-       mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) & ~MMCR0_FC);
-       rc = core_busy_loop();
-       mtspr(SPRN_MMCR0, mfspr(SPRN_MMCR0) |  MMCR0_FC);
-
-       return rc;
-}
-
 int ebb_child(union pipe read_pipe, union pipe write_pipe)
 {
        struct event event;

diff --git a/tools/testing/selftests/powerpc/pmu/ebb/ebb.h b/tools/testing/selftests/powerpc/pmu/ebb/ebb.h
index e62bde05bf7893a76c4c7db26aaa72fae95ae7cb..e44eee5d97ca47d53935058dfdf76108edae467a 100644 (file)
--- a/tools/testing/selftests/powerpc/pmu/ebb/ebb.h
+++ b/tools/testing/selftests/powerpc/pmu/ebb/ebb.h
@@ -70,7 +70,6 @@ int ebb_check_mmcr0(void);
 extern u64 sample_period;
 
 int core_busy_loop(void);
-int core_busy_loop_with_freeze(void);
 int ebb_child(union pipe read_pipe, union pipe write_pipe);
 int catch_sigill(void (*func)(void));
 void write_pmc1(void);