wireguard-linux/tools/perf/util/symbol.c, branch jd/unified-crypt-queue

perf symbols: Don't try to find a vmlinux file when looking for kernel modules

2020-03-03T19:20:01Z

The dso->kernel value is now set to everything that is in machine->kmaps, but that was being used to decide if vmlinux lookup is needed, which ended up making that lookup be made for kernel modules, that now have dso->kernel set, leading to these kinds of warnings when running on a machine with compressed kernel modules, like fedora:31: [root@five ~]# perf record -F 10000 -a sleep 2 [ perf record: Woken up 1 times to write data ] lzma: fopen failed on vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory' lzma: fopen failed on vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory' lzma: fopen failed on vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory' lzma: fopen failed on vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory' lzma: fopen failed on vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux: 'No such file or directory' lzma: fopen failed on /boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /usr/lib/debug/boot/vmlinux-5.5.5-200.fc31.x86_64: 'No such file or directory' lzma: fopen failed on /lib/modules/5.5.5-200.fc31.x86_64/build/vmlinux: 'No such file or directory' [ perf record: Captured and wrote 1.024 MB perf.data (1366 samples) ] [root@five ~]# This happens when collecting the buildid, when we find samples for kernel modules, fix it by checking if the looked up DSO is a kernel module by other means. Fixes: 02213cec64bb ("perf maps: Mark module DSOs with kernel type") Tested-by: Jiri Olsa Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Kim Phillips Cc: Michael Petlan Cc: Namhyung Kim Cc: Ravi Bangoria Link: http://lore.kernel.org/lkml/20200302191007.GD10335@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Convert symbol__is_idle() to use strlist

2020-02-10T19:30:51Z

Use the more optimized strlist implementation to do the idle function lookup. Signed-off-by: Kim Phillips Acked-by: Song Liu Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Andi Kleen Cc: Cong Wang Cc: Davidlohr Bueso Cc: Jin Yao Cc: Jiri Olsa Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200210163147.25358-1-kim.phillips@amd.com Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Update the list of kernel idle symbols

2020-02-10T19:30:13Z

The "acpi_idle_do_entry", "acpi_processor_ffh_cstate_enter", and "idle_cpu" symbols appear in 'perf top' output, at least on AMD systems. Add them to perf's idle_symbols list, so they don't dominate 'perf top' output. Signed-off-by: Kim Phillips Acked-by: Jiri Olsa Acked-by: Song Liu Cc: Alexander Shishkin Cc: Andi Kleen Cc: Cong Wang Cc: Davidlohr Bueso Cc: Jin Yao Cc: Kan Liang Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200207230613.26709-2-kim.phillips@amd.com Signed-off-by: Arnaldo Carvalho de Melo

perf maps: Rename 'mg' variables to 'maps'

2019-11-26T14:07:46Z

Continuing the merge of 'struct maps' with 'struct map_groups'. Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-z8d14wrw393a0fbvmnk1bqd9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf maps: Merge 'struct maps' with 'struct map_groups'

2019-11-26T14:07:46Z

And pick the shortest name: 'struct maps'. The split existed because we used to have two groups of maps, one for functions and one for variables, but that only complicated things, sometimes we needed to figure out what was at some address and then had to first try it on the functions group and if that failed, fall back to the variables one. That split is long gone, so for quite a while we had only one struct maps per struct map_groups, simplify things by combining those structs. First patch is the minimum needed to merge both, follow up patches will rename 'thread->mg' to 'thread->maps', etc. Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-hom6639ro7020o708trhxh59@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf map_groups: Auto sort maps by name, if needed

2019-11-18T16:01:58Z

There are still lots of lookups by name, even if just when loading vmlinux, till that code is studied to figure out if its possible to do away with those map lookup by names, provide a way to sort it using libc's qsort/bsearch. Doing it at the first lookup defers the sorting a bit, and as the code stands now, is never done for user maps, just for the kernel ones. # perf probe -l # perf probe -x ~/bin/perf -L __map_groups__find_by_name <__map_groups__find_by_name@/home/acme/git/perf/tools/perf/util/symbol.c:0> 0 static struct map *__map_groups__find_by_name(struct map_groups *mg, const char *name) 1 { struct map **mapp; 4 if (mg->maps_by_name == NULL && 5 map__groups__sort_by_name_from_rbtree(mg)) 6 return NULL; 8 mapp = bsearch(name, mg->maps_by_name, mg->nr_maps, sizeof(*mapp), map__strcmp_name); 9 if (mapp) 10 return *mapp; 11 return NULL; 12 } struct map *map_groups__find_by_name(struct map_groups *mg, const char *name) { # perf probe -x ~/bin/perf 'found=__map_groups__find_by_name:10 name:string' Added new event: probe_perf:found (on __map_groups__find_by_name:10 in /home/acme/bin/perf with name:string) You can now use it in all perf tools, such as: perf record -e probe_perf:found -aR sleep 1 # # perf probe -x ~/bin/perf -L map_groups__find_by_name 0 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name) 1 { 2 struct maps *maps = &mg->maps; struct map *map; 5 down_read(&maps->lock); 7 if (mg->last_search_by_name && strcmp(mg->last_search_by_name->dso->short_name, name) == 0) { 8 map = mg->last_search_by_name; 9 goto out_unlock; } /* * If we have mg->maps_by_name, then the name isn't in the rbtree, * as mg->maps_by_name mirrors the rbtree when lookups by name are * made. */ 16 map = __map_groups__find_by_name(mg, name); 17 if (map || mg->maps_by_name != NULL) 18 goto out_unlock; /* Fallback to traversing the rbtree... */ 21 maps__for_each_entry(maps, map) 22 if (strcmp(map->dso->short_name, name) == 0) { 23 mg->last_search_by_name = map; 24 goto out_unlock; } 27 map = NULL; out_unlock: 30 up_read(&maps->lock); 31 return map; 32 } int dso__load_vmlinux(struct dso *dso, struct map *map, const char *vmlinux, bool vmlinux_allocated) # perf probe -x ~/bin/perf 'fallback=map_groups__find_by_name:21 name:string' Added new events: probe_perf:fallback (on map_groups__find_by_name:21 in /home/acme/bin/perf with name:string) probe_perf:fallback_1 (on map_groups__find_by_name:21 in /home/acme/bin/perf with name:string) You can now use it in all perf tools, such as: perf record -e probe_perf:fallback_1 -aR sleep 1 # # perf probe -l probe_perf:fallback (on map_groups__find_by_name:21@util/symbol.c in /home/acme/bin/perf with name_string) probe_perf:fallback_1 (on map_groups__find_by_name:21@util/symbol.c in /home/acme/bin/perf with name_string) probe_perf:found (on __map_groups__find_by_name:10@util/symbol.c in /home/acme/bin/perf with name_string) # # perf stat -e probe_perf:* Now run 'perf top' in another term and then, after a while, stop 'perf stat': Furthermore, if we ask for interval printing, we can see that that is done just at the start of the workload: # perf stat -I1000 -e probe_perf:* # time counts unit events 1.000319513 0 probe_perf:found 1.000319513 0 probe_perf:fallback_1 1.000319513 0 probe_perf:fallback 2.001868092 23,251 probe_perf:found 2.001868092 0 probe_perf:fallback_1 2.001868092 0 probe_perf:fallback 3.002901597 0 probe_perf:found 3.002901597 0 probe_perf:fallback_1 3.002901597 0 probe_perf:fallback 4.003358591 0 probe_perf:found 4.003358591 0 probe_perf:fallback_1 4.003358591 0 probe_perf:fallback ^C # Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-c5lmbyr14x448rcfii7y6t3k@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf machine: No need to check if kernel module maps pre-exist

2019-11-18T16:01:50Z

We'only populating maps for kernel modules either from perf.data file PERF_RECORD_MMAP records or when parsing /proc/modules, so there is no need to first look if we already have those module maps in the list, that would mean the kernel has duplicate entries. So ditch one use of looking up maps by name. Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-gnzjg2hhuz6jnrw91m35059y@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf map_groups: Add a front end cache for map lookups by name

2019-11-18T14:21:32Z

Lets see if it helps: First look at the probeable lines for the function that does lookups by name in a map_groups struct: # perf probe -x ~/bin/perf -L map_groups__find_by_name 0 struct map *map_groups__find_by_name(struct map_groups *mg, const char *name) 1 { 2 struct maps *maps = &mg->maps; struct map *map; 5 down_read(&maps->lock); 7 if (mg->last_search_by_name && strcmp(mg->last_search_by_name->dso->short_name, name) == 0) { 8 map = mg->last_search_by_name; 9 goto out_unlock; } 12 maps__for_each_entry(maps, map) 13 if (strcmp(map->dso->short_name, name) == 0) { 14 mg->last_search_by_name = map; 15 goto out_unlock; } 18 map = NULL; out_unlock: 21 up_read(&maps->lock); 22 return map; 23 } int dso__load_vmlinux(struct dso *dso, struct map *map, const char *vmlinux, bool vmlinux_allocated) # Now add a probe to the place where we reuse the last search: # perf probe -x ~/bin/perf map_groups__find_by_name:8 Added new event: probe_perf:map_groups__find_by_name (on map_groups__find_by_name:8 in /home/acme/bin/perf) You can now use it in all perf tools, such as: perf record -e probe_perf:map_groups__find_by_name -aR sleep 1 # Now lets do a system wide 'perf stat' counting those events: # perf stat -e probe_perf:* Leave it running and lets do a 'perf top', then, after a while, stop the 'perf stat': # perf stat -e probe_perf:* ^C Performance counter stats for 'system wide': 3,603 probe_perf:map_groups__find_by_name 44.565253139 seconds time elapsed # yeah, good to have. Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-tcz37g3nxv3tvxw3q90vga3p@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf maps: Do not use an rbtree to sort by map name

2019-11-18T14:19:51Z

This is only used for the kernel maps, shave 24 bytes out 'struct map' and just traverse the existing per ip rbtree to look for maps by name, use a front end cache to reuse the last search if its the same name. After this 'struct map' is down to just two cachelines: $ pahole -C map ~/bin/perf struct map { union { struct rb_node rb_node __attribute__((__aligned__(8))); /* 0 24 */ struct list_head node; /* 0 16 */ } __attribute__((__aligned__(8))); /* 0 24 */ u64 start; /* 24 8 */ u64 end; /* 32 8 */ _Bool erange_warned; /* 40 1 */ /* XXX 3 bytes hole, try to pack */ u32 priv; /* 44 4 */ u32 prot; /* 48 4 */ u32 flags; /* 52 4 */ u64 pgoff; /* 56 8 */ /* --- cacheline 1 boundary (64 bytes) --- */ u64 reloc; /* 64 8 */ u32 maj; /* 72 4 */ u32 min; /* 76 4 */ u64 ino; /* 80 8 */ u64 ino_generation; /* 88 8 */ u64 (*map_ip)(struct map *, u64); /* 96 8 */ u64 (*unmap_ip)(struct map *, u64); /* 104 8 */ struct dso * dso; /* 112 8 */ refcount_t refcnt; /* 120 4 */ /* size: 128, cachelines: 2, members: 17 */ /* sum members: 121, holes: 1, sum holes: 3 */ /* padding: 4 */ /* forced alignments: 1 */ } __attribute__((__aligned__(8))); $ Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-bvr8fqfgzxtgnhnwt5sssx5g@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Use kmaps(map)->machine when we know its a kernel map

2019-11-12T11:20:53Z

And then stop using map->groups to achieve that. To test that that branch is being taken, probe the function that is only called from there and then run something like 'perf top' in another xterm: # perf probe -x ~/bin/perf machine__map_x86_64_entry_trampolines Added new event: probe_perf:machine__map_x86_64_entry_trampolines (on machine__map_x86_64_entry_trampolines in /home/acme/bin/perf) You can now use it in all perf tools, such as: perf record -e probe_perf:machine__map_x86_64_entry_trampolines -aR sleep 1 # perf trace -e probe_perf:* 0.000 bash/10614 probe_perf:machine__map_x86_64_entry_trampolines(__probe_ip: 5224944) ^C# Cc: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-lgrrzdxo2p9liq2keivcg887@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo