NAK: [SRU][Bionic][Cosmic][PATCH 0/1] Fix for perf top problem on s390x (LP: #1828166)
kleber.souza at canonical.com
Tue May 14 13:24:03 UTC 2019
On 5/9/19 2:44 PM, Kleber Sacilotto de Souza wrote:
> BugLink: https://bugs.launchpad.net/1828166
> * The perf top tool hangs and shows error messages, like 'Not enough
> memory for annotating'
> * edeb0c90df3581b821a764052d185df985f8b8dc edeb0c9 "perf tools: Stop
> fallbacking to kallsyms for vdso symbols lookup"
> * The patch can be cleany applied to Cosmic but needed a simple
> backport for Bionic for context adjustment.
> [Test Case]
> * start a benchmark (mem_alloc, but it doesn't really matter what)
> * execute perf top in a second terminal
> * the output of perf top is correct
> * now stop the benchmark
> * and perf top shows an error message, like "Not enough memory for
> annotating '__irf_end' symbol!)"
> * and perf top can't be exited anymore
> [Regression Potential]
> * The regression potential can be considered as low since this
> happens only while using the perf top tool
> * and it is known that the commit (above) fixes the problem
> * and the fix is upstream since 4.19
> Arnaldo Carvalho de Melo (1):
> perf tools: Stop fallbacking to kallsyms for vdso symbols lookup
> tools/perf/util/event.c | 21 ++-------------------
> 1 file changed, 2 insertions(+), 19 deletions(-)
This patch doesn't really fix the issue reported, so I'm NAK'ing
it and will not apply the patch until we are sure of the fix.
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