client: fix the pd client could be blocked in some cases (#3283)

[ti-srebot]

cherry-pick #3283 to release-4.0

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Signed-off-by: leoppro zhaoyilin@pingcap.com

What problem does this PR solve?

Fix the PD client could be blocked in some cases

What is changed and how it works?

There are two levels of context in PD client: client context and tso request context.
the tsoRequest.Wait() function could be blocked when the client context is canceled because the Wait() function haven't listened the client context

Benchmark

the version of PD server: v4.0.8

before this PR:

Start benchmark #0, duration: 5s
Create 3 client(s) for benchmark
count:768290, max:9, min:0, avg:0, >1ms:34372, >2ms:2037, >5ms:457, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:800952, max:9, min:0, avg:0, >1ms:96750, >2ms:13593, >5ms:1495, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:745906, max:8, min:0, avg:0, >1ms:12877, >2ms:3652, >5ms:1330, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:759058, max:4, min:0, avg:0, >1ms:11232, >2ms:5776, >5ms:0, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0

Total:
count:3074206, max:9, min:0, avg:0, >1ms:155231, >2ms:25058, >5ms:3282, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:3074206, >1ms:5.05%, >2ms:0.82%, >5ms:0.11%, >10ms:0.00%, >30ms:0.00% >50ms:0.00% >100ms:0.00% >200ms:0.00% >400ms:0.00% >800ms:0.00% >1s:0.00%

after this PR:

Start benchmark #0, duration: 5s
Create 3 client(s) for benchmark
count:1361814, max:7, min:0, avg:1, >1ms:900605, >2ms:204456, >5ms:2896, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:1357623, max:11, min:0, avg:1, >1ms:931611, >2ms:151281, >5ms:3936, >10ms:1, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:737217, max:7, min:0, avg:0, >1ms:3830, >2ms:3444, >5ms:1028, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:1033124, max:8, min:0, avg:0, >1ms:430725, >2ms:83313, >5ms:460, >10ms:0, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0

Total:
count:4489778, max:11, min:0, avg:1, >1ms:2266771, >2ms:442494, >5ms:8320, >10ms:1, >30ms:0 >50ms:0 >100ms:0 >200ms:0 >400ms:0 >800ms:0 >1s:0
count:4489778, >1ms:50.49%, >2ms:9.86%, >5ms:0.19%, >10ms:0.00%, >30ms:0.00% >50ms:0.00% >100ms:0.00% >200ms:0.00% >400ms:0.00% >800ms:0.00% >1s:0.00%

Check List

Tests

• Unit test

Release note

• Fix the pd client could be blocked in some cases

[ti-srebot]

@leoppro please accept the invitation then you can push to the cherry-pick pull requests.
https://github.com/ti-srebot/pd/invitations

[JmPotato]

@leoppro Please resolve the conflicts.

[JmPotato]

@leoppro It seems that applying suggestions doesn't have sign-off and misses fomating to the codes.

[JmPotato]

/lgtm

[codecov]

Codecov Report

Merging #3285 (2dc9207) into release-4.0 (35e2d08) will decrease coverage by 0.09%.
The diff coverage is 75.00%.

@@               Coverage Diff               @@
##           release-4.0    #3285      +/-   ##
===============================================
- Coverage        74.68%   74.59%   -0.10%     
===============================================
  Files              209      209              
  Lines            19591    19594       +3     
===============================================
- Hits             14632    14616      -16     
- Misses            3633     3645      +12     
- Partials          1326     1333       +7     

Flag	Coverage Δ
unittests	74.59% <75.00%> (-0.10%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
client/client.go	69.03% <75.00%> (+0.23%)	⬆️
pkg/tempurl/tempurl.go	60.00% <0.00%> (-10.00%)	⬇️
pkg/etcdutil/etcdutil.go	76.47% <0.00%> (-5.89%)	⬇️
pkg/dashboard/adapter/manager.go	77.17% <0.00%> (-4.35%)	⬇️
server/member/leader.go	63.76% <0.00%> (-2.76%)	⬇️
server/api/member.go	52.25% <0.00%> (-2.71%)	⬇️
pkg/btree/btree.go	85.30% <0.00%> (-0.97%)	⬇️
server/server.go	73.16% <0.00%> (-0.84%)	⬇️
server/handler.go	44.27% <0.00%> (-0.50%)	⬇️
... and 4 more

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[nolouch]

/merge

[ti-chi-bot]

@nolouch: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/ti-community-prow repository.

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: f4e5e7f

[ti-chi-bot]

@ti-srebot: Your PR has out-of-dated and I have automatically updated it for you.
At the same time I will also trigger all tests for you:

/run-all-tests

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/ti-community-prow repository.