From 9fa688ea341231837915f996b61f6e0a330d3b38 Mon Sep 17 00:00:00 2001 From: Ian Rogers Date: Mon, 27 Nov 2023 14:08:24 -0800 Subject: [PATCH] perf map: Simplify map_ip/unmap_ip and make 'struct map' smaller 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 Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Jajeev Cc: Changbin Du Cc: Colin Ian King Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: German Gomez Cc: Guilherme Amadio Cc: Huacai Chen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: K Prateek Nayak Cc: Kajol Jain Cc: Kan Liang Cc: Leo Yan Cc: Li Dong Cc: Liam Howlett Cc: Mark Rutland Cc: Masami Hiramatsu (Google) Cc: Miguel Ojeda Cc: Ming Wang Cc: Nick Terrell Cc: Paolo Bonzini Cc: Peter Zijlstra Cc: Ravi Bangoria Cc: Sandipan Das Cc: Sean Christopherson Cc: Steinar H. Gunderson Cc: Vincent Whitchurch Cc: Wenyu Liu Cc: Yang Jihong Link: https://lore.kernel.org/r/20231127220902.1315692-13-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/machine.c | 3 +- tools/perf/util/map.c | 20 +-------- tools/perf/util/map.h | 83 +++++++++++++++++++----------------- tools/perf/util/symbol-elf.c | 6 +-- tools/perf/util/symbol.c | 6 +-- 5 files changed, 50 insertions(+), 68 deletions(-) diff --git a/tools/perf/util/machine.c b/tools/perf/util/machine.c index a985d004aa8d..c5de5363b5e7 100644 --- a/tools/perf/util/machine.c +++ b/tools/perf/util/machine.c @@ -1359,8 +1359,7 @@ __machine__create_kernel_maps(struct machine *machine, struct dso *kernel) 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); } diff --git a/tools/perf/util/map.c b/tools/perf/util/map.c index f64b83004421..54c67cb7ecef 100644 --- a/tools/perf/util/map.c +++ b/tools/perf/util/map.c @@ -109,8 +109,7 @@ void map__init(struct map *map, u64 start, u64 end, u64 pgoff, struct dso *dso) 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); } @@ -172,7 +171,7 @@ struct map *map__new(struct machine *machine, u64 start, u64 len, 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_* @@ -630,18 +629,3 @@ struct maps *map__kmaps(struct map *map) } 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; -} diff --git a/tools/perf/util/map.h b/tools/perf/util/map.h index 1b53d53adc86..3a3b7757da5f 100644 --- a/tools/perf/util/map.h +++ b/tools/perf/util/map.h @@ -16,23 +16,25 @@ struct dso; 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; @@ -41,38 +43,11 @@ struct kmap *__map__kmap(struct map *map); 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; @@ -123,6 +98,34 @@ static inline size_t map__size(const struct map *map) 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); @@ -294,13 +297,13 @@ static inline void map__set_dso(struct map *map, struct dso *dso) 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 */ diff --git a/tools/perf/util/symbol-elf.c b/tools/perf/util/symbol-elf.c index 9e7eeaf616b8..4b934ed3bfd1 100644 --- a/tools/perf/util/symbol-elf.c +++ b/tools/perf/util/symbol-elf.c @@ -1392,8 +1392,7 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, 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; @@ -1455,8 +1454,7 @@ static int dso__process_kernel_symbol(struct dso *dso, struct map *map, 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)) diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 82cc74b9358e..314c0263bf3c 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -956,8 +956,7 @@ static int maps__split_kallsyms(struct maps *kmaps, struct dso *dso, u64 delta, 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; @@ -1475,8 +1474,7 @@ static int dso__load_kcore(struct dso *dso, struct map *map, 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);