Home
last modified time | relevance | path

Searched hist:c66a36af7ba3a628453da1d91f42ee64fb36ea5a (Results 1 – 2 of 2) sorted by relevance

/openbmc/linux/tools/perf/util/
H A Dbpf_lock_contention.cdiff 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>
/openbmc/linux/tools/perf/util/bpf_skel/
H A Dlock_contention.bpf.cdiff 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>