| Message ID | 5c0506e2d1bcdd513b9917716702c9bc5f656198.1728473602.git.petrm@nvidia.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | selftests: net: Introduce deferred commands | expand |
Hi, On 10/9/24 14:06, Petr Machata wrote: > diff --git a/tools/testing/selftests/net/lib/sh/defer.sh b/tools/testing/selftests/net/lib/sh/defer.sh > new file mode 100644 > index 000000000000..8d205c3f0445 > --- /dev/null > +++ b/tools/testing/selftests/net/lib/sh/defer.sh > @@ -0,0 +1,115 @@ > +#!/bin/bash > +# SPDX-License-Identifier: GPL-2.0 > + > +# map[(scope_id,track,cleanup_id) -> cleanup_command] > +# track={d=default | p=priority} > +declare -A __DEFER__JOBS > + > +# map[(scope_id,track) -> # cleanup_commands] > +declare -A __DEFER__NJOBS > + > +# scope_id of the topmost scope. > +__DEFER__SCOPE_ID=0 > + > +__defer__ndefer_key() > +{ > + local track=$1; shift Minor nit: IMHO the trailing shift is here a bit confusing: it let me think about other arguments, which are not really expected. [...] > +__defer__schedule() > +{ > + local track=$1; shift > + local ndefers=$(__defer__ndefers $track) > + local ndefers_key=$(__defer__ndefer_key $track) > + local defer_key=$(__defer__defer_key $track $ndefers) > + local defer="$@" > + > + __DEFER__JOBS[$defer_key]="$defer" > + __DEFER__NJOBS[$ndefers_key]=$((${__DEFER__NJOBS[$ndefers_key]} + 1)) '${__DEFER__NJOBS[$ndefers_key]}' is actually '$ndefers', right? If so it would be better to reuse the avail variable. Thanks, Paolo
Paolo Abeni <pabeni@redhat.com> writes: > Hi, > > On 10/9/24 14:06, Petr Machata wrote: >> diff --git a/tools/testing/selftests/net/lib/sh/defer.sh b/tools/testing/selftests/net/lib/sh/defer.sh >> new file mode 100644 >> index 000000000000..8d205c3f0445 >> --- /dev/null >> +++ b/tools/testing/selftests/net/lib/sh/defer.sh >> @@ -0,0 +1,115 @@ >> +#!/bin/bash >> +# SPDX-License-Identifier: GPL-2.0 >> + >> +# map[(scope_id,track,cleanup_id) -> cleanup_command] >> +# track={d=default | p=priority} >> +declare -A __DEFER__JOBS >> + >> +# map[(scope_id,track) -> # cleanup_commands] >> +declare -A __DEFER__NJOBS >> + >> +# scope_id of the topmost scope. >> +__DEFER__SCOPE_ID=0 >> + >> +__defer__ndefer_key() >> +{ >> + local track=$1; shift > > Minor nit: IMHO the trailing shift is here a bit confusing: it let me > think about other arguments, which are not really expected. This is IMHO how a function header should look like: function() { local foo=$1; shift local bar=$1; shift local baz=$1; shift ... } Because it lets you reorder the arguments freely just by reordering the lines, copy argument subsets to other functions without risking forgetting / screwing up renumbering, etc. It's easy to parse visually as well. If the function uses "$@" as rest argument, it will contain the rest by default. It's just a very convenient notation overall. Vast majority of net/lib.sh and net/forwarding/lib.sh use this. >> +__defer__schedule() >> +{ >> + local track=$1; shift >> + local ndefers=$(__defer__ndefers $track) >> + local ndefers_key=$(__defer__ndefer_key $track) >> + local defer_key=$(__defer__defer_key $track $ndefers) >> + local defer="$@" >> + >> + __DEFER__JOBS[$defer_key]="$defer" >> + __DEFER__NJOBS[$ndefers_key]=$((${__DEFER__NJOBS[$ndefers_key]} + 1)) > > '${__DEFER__NJOBS[$ndefers_key]}' is actually '$ndefers', right? If so > it would be better to reuse the avail variable. I figured I would leave it all spelled out, because the left hand side needs to be, and having the same expression on both sides makes it clear that this is just an X++ sort of a deal.
diff --git a/tools/testing/selftests/net/forwarding/lib.sh b/tools/testing/selftests/net/forwarding/lib.sh index c992e385159c..d24b6af7ebfa 100644 --- a/tools/testing/selftests/net/forwarding/lib.sh +++ b/tools/testing/selftests/net/forwarding/lib.sh @@ -1403,7 +1403,8 @@ tests_run() local current_test for current_test in ${TESTS:-$ALL_TESTS}; do - $current_test + in_defer_scope \ + $current_test done } diff --git a/tools/testing/selftests/net/lib.sh b/tools/testing/selftests/net/lib.sh index be8707bfb46e..c8991cc6bf28 100644 --- a/tools/testing/selftests/net/lib.sh +++ b/tools/testing/selftests/net/lib.sh @@ -1,6 +1,9 @@ #!/bin/bash # SPDX-License-Identifier: GPL-2.0 +net_dir=$(dirname "$(readlink -e "${BASH_SOURCE[0]}")") +source "$net_dir/lib/sh/defer.sh" + ############################################################################## # Defines diff --git a/tools/testing/selftests/net/lib/Makefile b/tools/testing/selftests/net/lib/Makefile index 82c3264b115e..18b9443454a9 100644 --- a/tools/testing/selftests/net/lib/Makefile +++ b/tools/testing/selftests/net/lib/Makefile @@ -10,6 +10,6 @@ TEST_FILES += ../../../../net/ynl TEST_GEN_FILES += csum -TEST_INCLUDES := $(wildcard py/*.py) +TEST_INCLUDES := $(wildcard py/*.py sh/*.sh) include ../../lib.mk diff --git a/tools/testing/selftests/net/lib/sh/defer.sh b/tools/testing/selftests/net/lib/sh/defer.sh new file mode 100644 index 000000000000..8d205c3f0445 --- /dev/null +++ b/tools/testing/selftests/net/lib/sh/defer.sh @@ -0,0 +1,115 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0 + +# map[(scope_id,track,cleanup_id) -> cleanup_command] +# track={d=default | p=priority} +declare -A __DEFER__JOBS + +# map[(scope_id,track) -> # cleanup_commands] +declare -A __DEFER__NJOBS + +# scope_id of the topmost scope. +__DEFER__SCOPE_ID=0 + +__defer__ndefer_key() +{ + local track=$1; shift + + echo $__DEFER__SCOPE_ID,$track +} + +__defer__defer_key() +{ + local track=$1; shift + local defer_ix=$1; shift + + echo $__DEFER__SCOPE_ID,$track,$defer_ix +} + +__defer__ndefers() +{ + local track=$1; shift + + echo ${__DEFER__NJOBS[$(__defer__ndefer_key $track)]} +} + +__defer__run() +{ + local track=$1; shift + local defer_ix=$1; shift + local defer_key=$(__defer__defer_key $track $defer_ix) + + ${__DEFER__JOBS[$defer_key]} + unset __DEFER__JOBS[$defer_key] +} + +__defer__schedule() +{ + local track=$1; shift + local ndefers=$(__defer__ndefers $track) + local ndefers_key=$(__defer__ndefer_key $track) + local defer_key=$(__defer__defer_key $track $ndefers) + local defer="$@" + + __DEFER__JOBS[$defer_key]="$defer" + __DEFER__NJOBS[$ndefers_key]=$((${__DEFER__NJOBS[$ndefers_key]} + 1)) +} + +__defer__scope_wipe() +{ + __DEFER__NJOBS[$(__defer__ndefer_key d)]=0 + __DEFER__NJOBS[$(__defer__ndefer_key p)]=0 +} + +defer_scope_push() +{ + ((__DEFER__SCOPE_ID++)) + __defer__scope_wipe +} + +defer_scope_pop() +{ + local defer_ix + + for ((defer_ix=$(__defer__ndefers p); defer_ix-->0; )); do + __defer__run p $defer_ix + done + + for ((defer_ix=$(__defer__ndefers d); defer_ix-->0; )); do + __defer__run d $defer_ix + done + + __defer__scope_wipe + ((__DEFER__SCOPE_ID--)) +} + +defer() +{ + __defer__schedule d "$@" +} + +defer_prio() +{ + __defer__schedule p "$@" +} + +defer_scopes_cleanup() +{ + while ((__DEFER__SCOPE_ID >= 0)); do + defer_scope_pop + done +} + +in_defer_scope() +{ + local ret + + defer_scope_push + "$@" + ret=$? + defer_scope_pop + + return $ret +} + +__defer__scope_wipe
In commit 8510801a9dbd ("selftests: drv-net: add ability to schedule cleanup with defer()"), a defer helper was added to Python selftests. The idea is to keep cleanup commands close to their dirtying counterparts, thereby making it more transparent what is cleaning up what, making it harder to miss a cleanup, and make the whole cleanup business exception safe. All these benefits are applicable to bash as well, exception safety can be interpreted in terms of safety vs. a SIGINT. This patch therefore introduces a framework of several helpers that serve to schedule cleanups in bash selftests: - defer_scope_push(), defer_scope_pop(): Deferred statements can be batched together in scopes. When a scope is popped, the deferred commands scheduled in that scope are executed in the order opposite to order of their scheduling. - defer(): Schedules a defer to the most recently pushed scope (or the default scope if none was pushed.) - defer_prio(): Schedules a defer on the priority track. The priority defer queue is run before the default defer queue when scope is popped. The issue that this is addressing is specifically the one of restoring devlink shared buffer threshold type. When setting up static thresholds, one has to first change the threshold type to static, then override the individual thresholds. When cleaning up, it would be natural to reset the threshold values first, then change the threshold type. But the values that are valid for dynamic thresholds are generally invalid for static thresholds and vice versa. Attempts to restore the values first would be bounced. Thus one has to first reset the threshold type, then adjust the thresholds. (You could argue that the shared buffer threshold type API is broken and you would be right, but here we are.) This cannot be solved by pure defers easily. I considered making it possible to disable an existing defer, so that one could then schedule a new defer and disable the original. But this forward-shifting of the defer job would have to take place after every threshold-adjusting command, which would make it very awkward to schedule these jobs. - defer_scopes_cleanup(): Pops any unpopped scopes, including the default one. The selftests that use defer should run this in their exit trap. This is important to get cleanups of interrupted scripts. - in_defer_scope(): Sometimes a function would like to introduce a new defer scope, then run whatever it is that it wants to run, and then pop the scope to run the deferred cleanups. The helper in_defer_scope() can be used to run another command within such environment, such that any scheduled defers run after the command finishes. The framework is added as a separate file lib/sh/defer.sh so that it can be used by all bash selftests, including those that do not currently use lib.sh. lib.sh however includes the file by default, because ideally all tests would use these helpers instead of hand-rolling their cleanups. Signed-off-by: Petr Machata <petrm@nvidia.com> --- tools/testing/selftests/net/forwarding/lib.sh | 3 +- tools/testing/selftests/net/lib.sh | 3 + tools/testing/selftests/net/lib/Makefile | 2 +- tools/testing/selftests/net/lib/sh/defer.sh | 115 ++++++++++++++++++ 4 files changed, 121 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/net/lib/sh/defer.sh