Searched hist:c66a36af7ba3a628453da1d91f42ee64fb36ea5a (Results 1 – 2 of 2) sorted by relevance
/openbmc/linux/tools/perf/util/ |
H A D | bpf_lock_contention.c | diff c66a36af7ba3a628453da1d91f42ee64fb36ea5a Fri Nov 18 13:01:09 CST 2022 Namhyung Kim <namhyung@kernel.org> perf lock contention: Do not use BPF task local storage
It caused some troubles when a lock inside kmalloc is contended because task local storage would allocate memory using kmalloc. It'd create a recusion and even crash in my system.
There could be a couple of workarounds but I think the simplest one is to use a pre-allocated hash map. We could fix the task local storage to use the safe BPF allocator, but it takes time so let's change this until it happens actually.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Blake Jones <blakejones@google.com> Cc: Chris Li <chriscli@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20221118190109.1512674-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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/openbmc/linux/tools/perf/util/bpf_skel/ |
H A D | lock_contention.bpf.c | diff c66a36af7ba3a628453da1d91f42ee64fb36ea5a Fri Nov 18 13:01:09 CST 2022 Namhyung Kim <namhyung@kernel.org> perf lock contention: Do not use BPF task local storage
It caused some troubles when a lock inside kmalloc is contended because task local storage would allocate memory using kmalloc. It'd create a recusion and even crash in my system.
There could be a couple of workarounds but I think the simplest one is to use a pre-allocated hash map. We could fix the task local storage to use the safe BPF allocator, but it takes time so let's change this until it happens actually.
Signed-off-by: Namhyung Kim <namhyung@kernel.org> Acked-by: Martin KaFai Lau <martin.lau@kernel.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Blake Jones <blakejones@google.com> Cc: Chris Li <chriscli@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Song Liu <song@kernel.org> Cc: bpf@vger.kernel.org Link: https://lore.kernel.org/r/20221118190109.1512674-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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