When mapping an IP it is either an identity mapping or a DSO relative
mapping, so a single bit is required in the struct to identify
this.
The current code uses function pointers, adding 2 pointers per map and
also pushing the size of a map beyond 1 cache line.
Switch to using a byte to identify the mapping type (as well as priv and
erange_warned), to avoid any masking.
Change struct maps's layout to avoid holes.
Before:
```
struct map {
u64 start; /* 0 8 */
u64 end; /* 8 8 */
_Bool erange_warned:1; /* 16: 0 1 */
_Bool priv:1; /* 16: 1 1 */
/* XXX 6 bits hole, try to pack */
/* XXX 3 bytes hole, try to pack */
u32 prot; /* 20 4 */
u64 pgoff; /* 24 8 */
u64 reloc; /* 32 8 */
u64 (*map_ip)(const struct map *, u64); /* 40 8 */
u64 (*unmap_ip)(const struct map *, u64); /* 48 8 */
struct dso * dso; /* 56 8 */
/* --- cacheline 1 boundary (64 bytes) --- */
refcount_t refcnt; /* 64 4 */
u32 flags; /* 68 4 */
/* size: 72, cachelines: 2, members: 12 */
/* sum members: 68, holes: 1, sum holes: 3 */
/* sum bitfield members: 2 bits, bit holes: 1, sum bit holes: 6 bits */
/* last cacheline: 8 bytes */
};
```
After:
```
struct map {
u64 start; /* 0 8 */
u64 end; /* 8 8 */
u64 pgoff; /* 16 8 */
u64 reloc; /* 24 8 */
struct dso * dso; /* 32 8 */
refcount_t refcnt; /* 40 4 */
u32 prot; /* 44 4 */
u32 flags; /* 48 4 */
enum mapping_type mapping_type:8; /* 52: 0 4 */
/* Bitfield combined with next fields */
_Bool erange_warned; /* 53 1 */
_Bool priv; /* 54 1 */
/* size: 56, cachelines: 1, members: 11 */
/* padding: 1 */
/* last cacheline: 56 bytes */
};
```
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Li Dong <lidong@vivo.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20231127220902.1315692-13-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
if (machine->vmlinux_map == NULL)
return -ENOMEM;
- map__set_map_ip(machine->vmlinux_map, identity__map_ip);
- map__set_unmap_ip(machine->vmlinux_map, identity__map_ip);
+ map__set_mapping_type(machine->vmlinux_map, MAPPING_TYPE__IDENTITY);
return maps__insert(machine__kernel_maps(machine), machine->vmlinux_map);
}
map__set_pgoff(map, pgoff);
map__set_reloc(map, 0);
map__set_dso(map, dso__get(dso));
- map__set_map_ip(map, map__dso_map_ip);
- map__set_unmap_ip(map, map__dso_unmap_ip);
+ map__set_mapping_type(map, MAPPING_TYPE__DSO);
map__set_erange_warned(map, false);
refcount_set(map__refcnt(map), 1);
}
map__init(result, start, start + len, pgoff, dso);
if (anon || no_dso) {
- map->map_ip = map->unmap_ip = identity__map_ip;
+ map->mapping_type = MAPPING_TYPE__IDENTITY;
/*
* Set memory without DSO as loaded. All map__find_*
}
return kmap->kmaps;
}
-
-u64 map__dso_map_ip(const struct map *map, u64 ip)
-{
- return ip - map__start(map) + map__pgoff(map);
-}
-
-u64 map__dso_unmap_ip(const struct map *map, u64 ip)
-{
- return ip + map__start(map) - map__pgoff(map);
-}
-
-u64 identity__map_ip(const struct map *map __maybe_unused, u64 ip)
-{
- return ip;
-}
struct maps;
struct machine;
+enum mapping_type {
+ /* map__map_ip/map__unmap_ip are given as offsets in the DSO. */
+ MAPPING_TYPE__DSO,
+ /* map__map_ip/map__unmap_ip are just the given ip value. */
+ MAPPING_TYPE__IDENTITY,
+};
+
DECLARE_RC_STRUCT(map) {
u64 start;
u64 end;
- bool erange_warned:1;
- bool priv:1;
- u32 prot;
u64 pgoff;
u64 reloc;
-
- /* ip -> dso rip */
- u64 (*map_ip)(const struct map *, u64);
- /* dso rip -> ip */
- u64 (*unmap_ip)(const struct map *, u64);
-
struct dso *dso;
refcount_t refcnt;
+ u32 prot;
u32 flags;
+ enum mapping_type mapping_type:8;
+ bool erange_warned;
+ bool priv;
};
struct kmap;
struct kmap *map__kmap(struct map *map);
struct maps *map__kmaps(struct map *map);
-/* ip -> dso rip */
-u64 map__dso_map_ip(const struct map *map, u64 ip);
-/* dso rip -> ip */
-u64 map__dso_unmap_ip(const struct map *map, u64 ip);
-/* Returns ip */
-u64 identity__map_ip(const struct map *map __maybe_unused, u64 ip);
-
static inline struct dso *map__dso(const struct map *map)
{
return RC_CHK_ACCESS(map)->dso;
}
-static inline u64 map__map_ip(const struct map *map, u64 ip)
-{
- return RC_CHK_ACCESS(map)->map_ip(map, ip);
-}
-
-static inline u64 map__unmap_ip(const struct map *map, u64 ip)
-{
- return RC_CHK_ACCESS(map)->unmap_ip(map, ip);
-}
-
-static inline void *map__map_ip_ptr(struct map *map)
-{
- return RC_CHK_ACCESS(map)->map_ip;
-}
-
-static inline void* map__unmap_ip_ptr(struct map *map)
-{
- return RC_CHK_ACCESS(map)->unmap_ip;
-}
-
static inline u64 map__start(const struct map *map)
{
return RC_CHK_ACCESS(map)->start;
return map__end(map) - map__start(map);
}
+/* ip -> dso rip */
+static inline u64 map__dso_map_ip(const struct map *map, u64 ip)
+{
+ return ip - map__start(map) + map__pgoff(map);
+}
+
+/* dso rip -> ip */
+static inline u64 map__dso_unmap_ip(const struct map *map, u64 ip)
+{
+ return ip + map__start(map) - map__pgoff(map);
+}
+
+static inline u64 map__map_ip(const struct map *map, u64 ip)
+{
+ if ((RC_CHK_ACCESS(map)->mapping_type) == MAPPING_TYPE__DSO)
+ return map__dso_map_ip(map, ip);
+ else
+ return ip;
+}
+
+static inline u64 map__unmap_ip(const struct map *map, u64 ip)
+{
+ if ((RC_CHK_ACCESS(map)->mapping_type) == MAPPING_TYPE__DSO)
+ return map__dso_unmap_ip(map, ip);
+ else
+ return ip;
+}
+
/* rip/ip <-> addr suitable for passing to `objdump --start-address=` */
u64 map__rip_2objdump(struct map *map, u64 rip);
RC_CHK_ACCESS(map)->dso = dso;
}
-static inline void map__set_map_ip(struct map *map, u64 (*map_ip)(const struct map *map, u64 ip))
+static inline void map__set_mapping_type(struct map *map, enum mapping_type type)
{
- RC_CHK_ACCESS(map)->map_ip = map_ip;
+ RC_CHK_ACCESS(map)->mapping_type = type;
}
-static inline void map__set_unmap_ip(struct map *map, u64 (*unmap_ip)(const struct map *map, u64 rip))
+static inline enum mapping_type map__mapping_type(struct map *map)
{
- RC_CHK_ACCESS(map)->unmap_ip = unmap_ip;
+ return RC_CHK_ACCESS(map)->mapping_type;
}
#endif /* __PERF_MAP_H */
map__set_start(map, shdr->sh_addr + ref_reloc(kmap));
map__set_end(map, map__start(map) + shdr->sh_size);
map__set_pgoff(map, shdr->sh_offset);
- map__set_map_ip(map, map__dso_map_ip);
- map__set_unmap_ip(map, map__dso_unmap_ip);
+ map__set_mapping_type(map, MAPPING_TYPE__DSO);
/* Ensure maps are correctly ordered */
if (kmaps) {
int err;
map__set_end(curr_map, map__start(curr_map) + shdr->sh_size);
map__set_pgoff(curr_map, shdr->sh_offset);
} else {
- map__set_map_ip(curr_map, identity__map_ip);
- map__set_unmap_ip(curr_map, identity__map_ip);
+ map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY);
}
curr_dso->symtab_type = dso->symtab_type;
if (maps__insert(kmaps, curr_map))
return -1;
}
- map__set_map_ip(curr_map, identity__map_ip);
- map__set_unmap_ip(curr_map, identity__map_ip);
+ map__set_mapping_type(curr_map, MAPPING_TYPE__IDENTITY);
if (maps__insert(kmaps, curr_map)) {
dso__put(ndso);
return -1;
map__set_start(map, map__start(new_map));
map__set_end(map, map__end(new_map));
map__set_pgoff(map, map__pgoff(new_map));
- map__set_map_ip(map, map__map_ip_ptr(new_map));
- map__set_unmap_ip(map, map__unmap_ip_ptr(new_map));
+ map__set_mapping_type(map, map__mapping_type(new_map));
/* Ensure maps are correctly ordered */
map_ref = map__get(map);
maps__remove(kmaps, map_ref);