[tip: x86/mm] x86/mm/pat: Harmonize 'struct memtype *' local variable and function parameter use

From: tip-bot2 for Ingo Molnar
Date: Fri Jan 10 2020 - 12:59:54 EST


The following commit has been merged into the x86/mm branch of tip:

Commit-ID: baf65855baac302bbacf0ce17ed99b9c0940b930
Gitweb: https://git.kernel.org/tip/baf65855baac302bbacf0ce17ed99b9c0940b930
Author: Ingo Molnar <mingo@xxxxxxxxxx>
AuthorDate: Tue, 10 Dec 2019 10:07:23 +01:00
Committer: Ingo Molnar <mingo@xxxxxxxxxx>
CommitterDate: Tue, 10 Dec 2019 10:12:55 +01:00

x86/mm/pat: Harmonize 'struct memtype *' local variable and function parameter use

We have quite a zoo of 'struct memtype' variable nomenclature:

new
entry
print_entry
data
match
out
memtype

Beyond the randomness, some of these are outright confusing, especially
when used in larger functions.

Standardize them:

entry
entry_new
entry_old
entry_print
entry_match
entry_out

Signed-off-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
arch/x86/mm/pat.c | 51 ++++++++++-----------
arch/x86/mm/pat_internal.h | 6 +-
arch/x86/mm/pat_interval.c | 91 ++++++++++++++++++-------------------
3 files changed, 75 insertions(+), 73 deletions(-)

diff --git a/arch/x86/mm/pat.c b/arch/x86/mm/pat.c
index af04992..4a18049 100644
--- a/arch/x86/mm/pat.c
+++ b/arch/x86/mm/pat.c
@@ -576,7 +576,7 @@ static u64 sanitize_phys(u64 address)
int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
enum page_cache_mode *new_type)
{
- struct memtype *new;
+ struct memtype *entry_new;
enum page_cache_mode actual_type;
int is_range_ram;
int err = 0;
@@ -624,22 +624,22 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
return -EINVAL;
}

- new = kzalloc(sizeof(struct memtype), GFP_KERNEL);
- if (!new)
+ entry_new = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+ if (!entry_new)
return -ENOMEM;

- new->start = start;
- new->end = end;
- new->type = actual_type;
+ entry_new->start = start;
+ entry_new->end = end;
+ entry_new->type = actual_type;

spin_lock(&memtype_lock);

- err = memtype_check_insert(new, new_type);
+ err = memtype_check_insert(entry_new, new_type);
if (err) {
pr_info("x86/PAT: reserve_memtype failed [mem %#010Lx-%#010Lx], track %s, req %s\n",
start, end - 1,
- cattr_name(new->type), cattr_name(req_type));
- kfree(new);
+ cattr_name(entry_new->type), cattr_name(req_type));
+ kfree(entry_new);
spin_unlock(&memtype_lock);

return err;
@@ -648,7 +648,7 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
spin_unlock(&memtype_lock);

dprintk("reserve_memtype added [mem %#010Lx-%#010Lx], track %s, req %s, ret %s\n",
- start, end - 1, cattr_name(new->type), cattr_name(req_type),
+ start, end - 1, cattr_name(entry_new->type), cattr_name(req_type),
new_type ? cattr_name(*new_type) : "-");

return err;
@@ -657,7 +657,7 @@ int reserve_memtype(u64 start, u64 end, enum page_cache_mode req_type,
int free_memtype(u64 start, u64 end)
{
int is_range_ram;
- struct memtype *entry;
+ struct memtype *entry_old;

if (!pat_enabled())
return 0;
@@ -676,16 +676,16 @@ int free_memtype(u64 start, u64 end)
return -EINVAL;

spin_lock(&memtype_lock);
- entry = memtype_erase(start, end);
+ entry_old = memtype_erase(start, end);
spin_unlock(&memtype_lock);

- if (IS_ERR(entry)) {
+ if (IS_ERR(entry_old)) {
pr_info("x86/PAT: %s:%d freeing invalid memtype [mem %#010Lx-%#010Lx]\n",
current->comm, current->pid, start, end - 1);
return -EINVAL;
}

- kfree(entry);
+ kfree(entry_old);

dprintk("free_memtype request [mem %#010Lx-%#010Lx]\n", start, end - 1);

@@ -726,6 +726,7 @@ static enum page_cache_mode lookup_memtype(u64 paddr)
rettype = _PAGE_CACHE_MODE_UC_MINUS;

spin_unlock(&memtype_lock);
+
return rettype;
}

@@ -1130,24 +1131,24 @@ EXPORT_SYMBOL_GPL(pgprot_writethrough);
*/
static struct memtype *memtype_get_idx(loff_t pos)
{
- struct memtype *print_entry;
+ struct memtype *entry_print;
int ret;

- print_entry = kzalloc(sizeof(struct memtype), GFP_KERNEL);
- if (!print_entry)
+ entry_print = kzalloc(sizeof(struct memtype), GFP_KERNEL);
+ if (!entry_print)
return NULL;

spin_lock(&memtype_lock);
- ret = memtype_copy_nth_element(print_entry, pos);
+ ret = memtype_copy_nth_element(entry_print, pos);
spin_unlock(&memtype_lock);

/* Free it on error: */
if (ret) {
- kfree(print_entry);
+ kfree(entry_print);
return NULL;
}

- return print_entry;
+ return entry_print;
}

static void *memtype_seq_start(struct seq_file *seq, loff_t *pos)
@@ -1172,14 +1173,14 @@ static void memtype_seq_stop(struct seq_file *seq, void *v)

static int memtype_seq_show(struct seq_file *seq, void *v)
{
- struct memtype *print_entry = (struct memtype *)v;
+ struct memtype *entry_print = (struct memtype *)v;

seq_printf(seq, "PAT: [mem 0x%016Lx-0x%016Lx] %s\n",
- print_entry->start,
- print_entry->end,
- cattr_name(print_entry->type));
+ entry_print->start,
+ entry_print->end,
+ cattr_name(entry_print->type));

- kfree(print_entry);
+ kfree(entry_print);

return 0;
}
diff --git a/arch/x86/mm/pat_internal.h b/arch/x86/mm/pat_internal.h
index 79a0668..23ce8cd 100644
--- a/arch/x86/mm/pat_internal.h
+++ b/arch/x86/mm/pat_internal.h
@@ -29,13 +29,13 @@ static inline char *cattr_name(enum page_cache_mode pcm)
}

#ifdef CONFIG_X86_PAT
-extern int memtype_check_insert(struct memtype *new,
+extern int memtype_check_insert(struct memtype *entry_new,
enum page_cache_mode *new_type);
extern struct memtype *memtype_erase(u64 start, u64 end);
extern struct memtype *memtype_lookup(u64 addr);
-extern int memtype_copy_nth_element(struct memtype *out, loff_t pos);
+extern int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos);
#else
-static inline int memtype_check_insert(struct memtype *new,
+static inline int memtype_check_insert(struct memtype *entry_new,
enum page_cache_mode *new_type)
{ return 0; }
static inline struct memtype *memtype_erase(u64 start, u64 end)
diff --git a/arch/x86/mm/pat_interval.c b/arch/x86/mm/pat_interval.c
index 2abc475..3c983de 100644
--- a/arch/x86/mm/pat_interval.c
+++ b/arch/x86/mm/pat_interval.c
@@ -33,14 +33,14 @@
* memtype_lock protects the rbtree.
*/

-static inline u64 interval_start(struct memtype *memtype)
+static inline u64 interval_start(struct memtype *entry)
{
- return memtype->start;
+ return entry->start;
}

-static inline u64 interval_end(struct memtype *memtype)
+static inline u64 interval_end(struct memtype *entry)
{
- return memtype->end - 1;
+ return entry->end - 1;
}

INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
@@ -56,19 +56,20 @@ enum {

static struct memtype *memtype_match(u64 start, u64 end, int match_type)
{
- struct memtype *match;
+ struct memtype *entry_match;

- match = interval_iter_first(&memtype_rbroot, start, end-1);
- while (match != NULL && match->start < end) {
+ entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+
+ while (entry_match != NULL && entry_match->start < end) {
if ((match_type == MEMTYPE_EXACT_MATCH) &&
- (match->start == start) && (match->end == end))
- return match;
+ (entry_match->start == start) && (entry_match->end == end))
+ return entry_match;

if ((match_type == MEMTYPE_END_MATCH) &&
- (match->start < start) && (match->end == end))
- return match;
+ (entry_match->start < start) && (entry_match->end == end))
+ return entry_match;

- match = interval_iter_next(match, start, end-1);
+ entry_match = interval_iter_next(entry_match, start, end-1);
}

return NULL; /* Returns NULL if there is no match */
@@ -78,25 +79,25 @@ static int memtype_check_conflict(u64 start, u64 end,
enum page_cache_mode reqtype,
enum page_cache_mode *newtype)
{
- struct memtype *match;
+ struct memtype *entry_match;
enum page_cache_mode found_type = reqtype;

- match = interval_iter_first(&memtype_rbroot, start, end-1);
- if (match == NULL)
+ entry_match = interval_iter_first(&memtype_rbroot, start, end-1);
+ if (entry_match == NULL)
goto success;

- if (match->type != found_type && newtype == NULL)
+ if (entry_match->type != found_type && newtype == NULL)
goto failure;

- dprintk("Overlap at 0x%Lx-0x%Lx\n", match->start, match->end);
- found_type = match->type;
+ dprintk("Overlap at 0x%Lx-0x%Lx\n", entry_match->start, entry_match->end);
+ found_type = entry_match->type;

- match = interval_iter_next(match, start, end-1);
- while (match) {
- if (match->type != found_type)
+ entry_match = interval_iter_next(entry_match, start, end-1);
+ while (entry_match) {
+ if (entry_match->type != found_type)
goto failure;

- match = interval_iter_next(match, start, end-1);
+ entry_match = interval_iter_next(entry_match, start, end-1);
}
success:
if (newtype)
@@ -107,29 +108,29 @@ success:
failure:
pr_info("x86/PAT: %s:%d conflicting memory types %Lx-%Lx %s<->%s\n",
current->comm, current->pid, start, end,
- cattr_name(found_type), cattr_name(match->type));
+ cattr_name(found_type), cattr_name(entry_match->type));

return -EBUSY;
}

-int memtype_check_insert(struct memtype *new, enum page_cache_mode *ret_type)
+int memtype_check_insert(struct memtype *entry_new, enum page_cache_mode *ret_type)
{
int err = 0;

- err = memtype_check_conflict(new->start, new->end, new->type, ret_type);
+ err = memtype_check_conflict(entry_new->start, entry_new->end, entry_new->type, ret_type);
if (err)
return err;

if (ret_type)
- new->type = *ret_type;
+ entry_new->type = *ret_type;

- interval_insert(new, &memtype_rbroot);
+ interval_insert(entry_new, &memtype_rbroot);
return 0;
}

struct memtype *memtype_erase(u64 start, u64 end)
{
- struct memtype *data;
+ struct memtype *entry_old;

/*
* Since the memtype_rbroot tree allows overlapping ranges,
@@ -138,26 +139,26 @@ struct memtype *memtype_erase(u64 start, u64 end)
* it then checks with END_MATCH, i.e. shrink the size of a node
* from the end for the mremap case.
*/
- data = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
- if (!data) {
- data = memtype_match(start, end, MEMTYPE_END_MATCH);
- if (!data)
+ entry_old = memtype_match(start, end, MEMTYPE_EXACT_MATCH);
+ if (!entry_old) {
+ entry_old = memtype_match(start, end, MEMTYPE_END_MATCH);
+ if (!entry_old)
return ERR_PTR(-EINVAL);
}

- if (data->start == start) {
+ if (entry_old->start == start) {
/* munmap: erase this node */
- interval_remove(data, &memtype_rbroot);
+ interval_remove(entry_old, &memtype_rbroot);
} else {
/* mremap: update the end value of this node */
- interval_remove(data, &memtype_rbroot);
- data->end = start;
- interval_insert(data, &memtype_rbroot);
+ interval_remove(entry_old, &memtype_rbroot);
+ entry_old->end = start;
+ interval_insert(entry_old, &memtype_rbroot);

return NULL;
}

- return data;
+ return entry_old;
}

struct memtype *memtype_lookup(u64 addr)
@@ -171,20 +172,20 @@ struct memtype *memtype_lookup(u64 addr)
* via debugfs, without holding the memtype_lock too long:
*/
#ifdef CONFIG_DEBUG_FS
-int memtype_copy_nth_element(struct memtype *out, loff_t pos)
+int memtype_copy_nth_element(struct memtype *entry_out, loff_t pos)
{
- struct memtype *match;
+ struct memtype *entry_match;
int i = 1;

- match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
+ entry_match = interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);

- while (match && pos != i) {
- match = interval_iter_next(match, 0, ULONG_MAX);
+ while (entry_match && pos != i) {
+ entry_match = interval_iter_next(entry_match, 0, ULONG_MAX);
i++;
}

- if (match) { /* pos == i */
- *out = *match;
+ if (entry_match) { /* pos == i */
+ *entry_out = *entry_match;
return 0;
} else {
return 1;