[PATCH v2 1/3] riscv: Improve PTDUMP to show RSW with non-zero value
Yu Chien Peter Lin
peterlin at andestech.com
Wed Sep 13 18:40:25 PDT 2023
RSW field can be used to encode 2 bits of software defined
information, currently PTDUMP only prints RSW when its value
is 1 or 3.
To fix this issue and enhance the debug experience with PTDUMP,
we use _PAGE_SOFT as the RSW mask and redefine _PAGE_SPECIAL to
(1 << 8), allow it to print the RSW with any non-zero value,
otherwise, it will print an empty string for each row.
This patch also removes the val from the struct prot_bits as
it is no longer needed.
Signed-off-by: Yu Chien Peter Lin <peterlin at andestech.com>
---
arch/riscv/include/asm/pgtable-bits.h | 4 +--
arch/riscv/mm/ptdump.c | 36 +++++++++++----------------
2 files changed, 17 insertions(+), 23 deletions(-)
diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h
index f896708e8331..99e60fd3eb72 100644
--- a/arch/riscv/include/asm/pgtable-bits.h
+++ b/arch/riscv/include/asm/pgtable-bits.h
@@ -16,9 +16,9 @@
#define _PAGE_GLOBAL (1 << 5) /* Global */
#define _PAGE_ACCESSED (1 << 6) /* Set by hardware on any access */
#define _PAGE_DIRTY (1 << 7) /* Set by hardware on any write */
-#define _PAGE_SOFT (1 << 8) /* Reserved for software */
+#define _PAGE_SOFT (3 << 8) /* Reserved for software */
-#define _PAGE_SPECIAL _PAGE_SOFT
+#define _PAGE_SPECIAL (1 << 8)
#define _PAGE_TABLE _PAGE_PRESENT
/*
diff --git a/arch/riscv/mm/ptdump.c b/arch/riscv/mm/ptdump.c
index 20a9f991a6d7..85686652f342 100644
--- a/arch/riscv/mm/ptdump.c
+++ b/arch/riscv/mm/ptdump.c
@@ -129,7 +129,6 @@ static struct ptd_mm_info efi_ptd_info = {
/* Page Table Entry */
struct prot_bits {
u64 mask;
- u64 val;
const char *set;
const char *clear;
};
@@ -137,47 +136,38 @@ struct prot_bits {
static const struct prot_bits pte_bits[] = {
{
.mask = _PAGE_SOFT,
- .val = _PAGE_SOFT,
- .set = "RSW",
- .clear = " ",
+ .set = "RSW(%d)",
+ .clear = " ",
}, {
.mask = _PAGE_DIRTY,
- .val = _PAGE_DIRTY,
.set = "D",
.clear = ".",
}, {
.mask = _PAGE_ACCESSED,
- .val = _PAGE_ACCESSED,
.set = "A",
.clear = ".",
}, {
.mask = _PAGE_GLOBAL,
- .val = _PAGE_GLOBAL,
.set = "G",
.clear = ".",
}, {
.mask = _PAGE_USER,
- .val = _PAGE_USER,
.set = "U",
.clear = ".",
}, {
.mask = _PAGE_EXEC,
- .val = _PAGE_EXEC,
.set = "X",
.clear = ".",
}, {
.mask = _PAGE_WRITE,
- .val = _PAGE_WRITE,
.set = "W",
.clear = ".",
}, {
.mask = _PAGE_READ,
- .val = _PAGE_READ,
.set = "R",
.clear = ".",
}, {
.mask = _PAGE_PRESENT,
- .val = _PAGE_PRESENT,
.set = "V",
.clear = ".",
}
@@ -208,15 +198,19 @@ static void dump_prot(struct pg_state *st)
unsigned int i;
for (i = 0; i < ARRAY_SIZE(pte_bits); i++) {
- const char *s;
-
- if ((st->current_prot & pte_bits[i].mask) == pte_bits[i].val)
- s = pte_bits[i].set;
- else
- s = pte_bits[i].clear;
-
- if (s)
- pt_dump_seq_printf(st->seq, " %s", s);
+ char s[7];
+ unsigned long val;
+
+ val = st->current_prot & pte_bits[i].mask;
+ if (val) {
+ if (pte_bits[i].mask == _PAGE_SOFT)
+ sprintf(s, pte_bits[i].set, val >> 8);
+ else
+ sprintf(s, "%s", pte_bits[i].set);
+ } else
+ sprintf(s, "%s", pte_bits[i].clear);
+
+ pt_dump_seq_printf(st->seq, " %s", s);
}
}
--
2.34.1
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