kernel/tools/perf/util/namespaces.h, branch linux-5.14.y

perf inject jit: Add namespaces support

2021-02-03T16:10:44Z

This patch fixes "perf inject --jit" to properly operate on namespaced/containerized processes: * jitdump files are generated by the process, thus they should be looked up in its mount NS. * DSOs of injected MMAP events will later be looked up in the process mount NS, so write them into its NS. * PIDs & TIDs from jitdump events need to be translated to the PID as seen by "perf record" before written into MMAP events. For a process in a different PID NS, the TID & PID given in the jitdump event are actually ignored; I use the TID & PID of the thread which mmap()ed the jitdump file. This is simplified and won't do for forks of the initial process, if they continue using the same jitdump file. Future patches might improve it. This was tested by recording a NodeJS process running with "--perf-prof", inside a Docker container, and by recording another NodeJS process running in the same namespaces as perf itself, to make sure it's not broken for non-containerized processes. Signed-off-by: Yonatan Goldschmidt Acked-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Mark Rutland Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20201105015604.1726943-1-yonatan.goldschmidt@granulate.io Signed-off-by: Arnaldo Carvalho de Melo

perf namespaces: Add 'in_pidns' to nsinfo struct

2021-02-03T16:10:44Z

Provides an accurate mean to determine if the owner thread is in a different PID namespace. Signed-off-by: Yonatan Goldschmidt Acked-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Mark Rutland Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20201105015418.1725218-1-yonatan.goldschmidt@granulate.io Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Move event synthesizing routines to separate .c file

2019-09-20T13:28:21Z

For better grouping, in time we may end up making most of these static, i.e. generalizing the 'perf record' synthesizing code so that based on the target it can do the right thing and call the needed synthesizers. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-s9zxxhk40s95pjng9panet16@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

libperf: Rename the PERF_RECORD_ structs to have a "perf" suffix

2019-08-26T22:39:11Z

Even more, to have a "perf_record_" prefix, so that they match the PERF_RECORD_ enum they map to. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-qbabmcz2a0pkzt72liyuz3p8@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf namespaces: Move the conditional setns() prototype to namespaces.h

2019-07-09T13:13:26Z

Out of util.h, to reduce its scope, and since we have a namespaces.h header, much better to have it there, where it is related to. Cc: Adrian Hunter Cc: Jiri Olsa Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-zlu81bbtccuzygh7m8nmgybc@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55Z

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

perf tools: Restore proper cwd on return from mnt namespace

2018-11-19T20:12:26Z

When reporting on 'record' server we try to retrieve/use the mnt namespace of the profiled tasks. We use following API with cookie to hold the return namespace, roughly: nsinfo__mountns_enter(struct nsinfo *nsi, struct nscookie *nc) setns(newns, 0); ... new ns related open.. ... nsinfo__mountns_exit(struct nscookie *nc) setns(nc->oldns) Once finished we setns to old namespace, which also sets the current working directory (cwd) to "/", trashing the cwd we had. This is mostly fine, because we use absolute paths almost everywhere, but it screws up 'perf diff': # perf diff failed to open perf.data: No such file or directory (try 'perf record' first) ... Adding the current working directory to be part of the cookie and restoring it in the nsinfo__mountns_exit call. Signed-off-by: Jiri Olsa Cc: Alexander Shishkin Cc: Krister Johansen Cc: Namhyung Kim Cc: Peter Zijlstra Fixes: 843ff37bb59e ("perf symbols: Find symbols in different mount namespace") Link: http://lkml.kernel.org/r/20181101170001.30019-1-jolsa@kernel.org [ No need to check for NULL args for free(), use zfree() for struct members ] Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Fix the build on the alpine:edge distro

2018-07-30T16:15:03Z

The UAPI file byteorder/little_endian.h uses the __always_inline define without including the header where it is defined, linux/stddef.h, this ends up working in all the other distros because that file gets included seemingly by luck from one of the files included from little_endian.h. But not on Alpine:edge, that fails for all files where perf_event.h is included but linux/stddef.h isn't include before that. Adding the missing linux/stddef.h file where it breaks on Alpine:edge to fix that, in all other distros, that is just a very small header anyway. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Namhyung Kim Cc: Wang Nan Link: https://lkml.kernel.org/n/tip-9r1pifftxvuxms8l7ir73p5l@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf namespaces: Add more appropriate set of headers

2017-10-23T19:30:54Z

We don't need perf.h, that is a kitchen sink, all we need is perf_events.h for perf_ns_link_info, sys/types.h for pid_t and linux/types.h for u64, list_head. Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Li Zhijian Cc: Namhyung Kim Cc: Wang Nan Link: http://lkml.kernel.org/n/tip-f2uxyaj4s2hmntkrezpa6dqz@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Allow placing uprobes in alternate namespaces.

2017-07-19T02:14:10Z

Teaches perf how to place a uprobe on a file that's in a different mount namespace. The user must add the probe using the --target-ns argument to perf probe. Once it has been placed, it may be recorded against without further namespace-specific commands. Signed-off-by: Krister Johansen Cc: Alexander Shishkin Cc: Brendan Gregg Cc: Peter Zijlstra Cc: Ravi Bangoria [ PPC build fixed by Ravi: ] Link: http://lkml.kernel.org/r/1500287542-6219-1-git-send-email-ravi.bangoria@linux.vnet.ibm.com Cc: Thomas-Mich Richter [ Fix !HAVE_DWARF_SUPPORT build ] Link: http://lkml.kernel.org/r/1499305693-1599-4-git-send-email-kjlx@templeofstupid.com Signed-off-by: Arnaldo Carvalho de Melo