Messages in this thread Patch in this message | | | Date | Tue, 12 Dec 2023 09:16:54 +0000 | From | Will Deacon <> | Subject | Re: [PATCH] perf/arm-cmn: Fail DTC counter allocation correctly |
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On Mon, Dec 11, 2023 at 07:27:28PM +0000, Robin Murphy wrote: > Calling arm_cmn_event_clear() before all DTC indices are allocated is > wrong, and can lead to arm_cmn_event_add() erroneously clearing live > counters from full DTCs where allocation fails. Since the DTC counters > are only updated by arm_cmn_init_counter() after all DTC and DTM > allocations succeed, nothing actually needs cleaning up in this case > anyway, and it should just return directly as it did before. > > Fixes: 7633ec2c262f ("perf/arm-cmn: Rework DTC counters (again)") > Signed-off-by: Robin Murphy <robin.murphy@arm.com> > --- > drivers/perf/arm-cmn.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/perf/arm-cmn.c b/drivers/perf/arm-cmn.c > index 86d970e74129..c584165b13ba 100644 > --- a/drivers/perf/arm-cmn.c > +++ b/drivers/perf/arm-cmn.c > @@ -1816,7 +1816,7 @@ static int arm_cmn_event_add(struct perf_event *event, int flags) > idx = 0; > while (cmn->dtc[j].counters[idx]) > if (++idx == CMN_DT_NUM_COUNTERS) > - goto free_dtms; > + return -ENOSPC; > } > hw->dtc_idx[j] = idx; > } > -- > 2.39.2.101.g768bb238c484.dirty
Acked-by: Will Deacon <will@kernel.org>
Catalin -- please can you take this one as a fix?
Cheers,
Will
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