feat(bisect): Add new bisection feature

When kernel breaks we need to be able to use automated way
bisection, using bisect command. This is initial version,
that just works, but needs a bit more work to work reliably.
I prefer to commit early, so we don't accumulate too much
uncommited code.

Signed-off-by: Denys Fedoryshchenko <[email protected]>

kcidev/main.py

@@ -4,7 +4,8 @@
 import click
 
 from kcidev.libs.common import *
-from kcidev.subcommands import checkout, commit, patch, results, testretry
+from kcidev.subcommands import (bisect, checkout, commit, patch, results,
+                                testretry)
 
 
 @click.group(
@@ -35,6 +36,7 @@ def cli(ctx, settings, instance):
 
 
 def run():
+    cli.add_command(bisect.bisect)
     cli.add_command(checkout.checkout)
     cli.add_command(commit.commit)
     cli.add_command(patch.patch)

kcidev/subcommands/bisect.py

@@ -0,0 +1,292 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+
+import json
+import os
+import re
+import subprocess
+import sys
+
+import click
+import requests
+import toml
+from git import Repo
+
+"""
+To not lose the state of the bisection, we need to store the state in a file
+The state file is a json file that contains the following keys:
+- giturl: the repository url
+- branch: the repository branch
+- good: the known good commit
+- bad: the known bad commit
+- retryfail: the number of times to retry the failed test
+- history: the list of commits that have been tested (each entry has "commitid": state)
+"""
+default_state = {
+    "giturl": "",
+    "branch": "",
+    "retryfail": 0,
+    "good": "",
+    "bad": "",
+    "history": [],
+    "jobfilter": [],
+    "platformfilter": [],
+    "test": "",
+    "workdir": "",
+    "bisect_init": False,
+    "next_commit": None,
+}
+
+
+def api_connection(host):
+    click.secho("api connect: " + host, fg="green")
+    return host
+
+
+def load_state(file="state.json"):
+    if os.path.exists(file):
+        with open(file, "r") as f:
+            return json.load(f)
+    else:
+        return None
+
+
+def print_state(state):
+    click.secho("Loaded state file", fg="green")
+    click.secho("giturl: " + state["giturl"], fg="green")
+    click.secho("branch: " + state["branch"], fg="green")
+    click.secho("good: " + state["good"], fg="green")
+    click.secho("bad: " + state["bad"], fg="green")
+    click.secho("retryfail: " + str(state["retryfail"]), fg="green")
+    click.secho("history: " + str(state["history"]), fg="green")
+    click.secho("jobfilter: " + str(state["jobfilter"]), fg="green")
+    click.secho("platformfilter: " + str(state["platformfilter"]), fg="green")
+    click.secho("test: " + state["test"], fg="green")
+    click.secho("workdir: " + state["workdir"], fg="green")
+    click.secho("bisect_init: " + str(state["bisect_init"]), fg="green")
+    click.secho("next_commit: " + str(state["next_commit"]), fg="green")
+
+
+def save_state(state, file="state.json"):
+    with open(file, "w") as f:
+        json.dump(state, f)
+
+
+def git_exec_getcommit(cmd):
+    click.secho("Executing git command: " + " ".join(cmd), fg="green")
+    result = subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
+    if result.returncode != 0:
+        click.secho("git command return failed", fg="red")
+        sys.exit(1)
+    lines = result.stdout.split(b"\n")
+    if len(lines) < 2:
+        click.secho(f"git command answer length failed: {lines}", fg="red")
+        sys.exit(1)
+    # is it last bisect?: "is the first bad commit"
+    if "is the first bad commit" in str(lines[1]):
+        click.secho(f"git command: {lines}", fg="green")
+        # TBD save state somehow?
+        sys.exit(0)
+    re_commit = re.search(r"\[([a-f0-9]+)\]", str(lines[1]))
+    if not re_commit:
+        click.secho(f"git command regex failed: {lines}", fg="red")
+        sys.exit(1)
+    return re_commit.group(1)
+
+
+def kcidev_exec(cmd):
+    """
+    Execute a kci-dev and return the return code
+    """
+    process = None
+    click.secho("Executing kci-dev command: " + " " + str(cmd), fg="green")
+    with subprocess.Popen(
+        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, text=True
+    ) as process:
+        try:
+            for line in process.stdout:
+                click.echo(line, nl=False)
+            process.wait()
+        except Exception as e:
+            click.secho(f"Error executing kci-dev: {e}", fg="red")
+            sys.exit(1)
+
+    return process
+
+
+def init_bisect(state):
+    olddir = os.getcwd()
+    os.chdir(state["workdir"])
+    click.secho("init bisect", fg="green")
+    r = os.system("git bisect start")
+    if r != 0:
+        click.secho("git bisect start failed", fg="red")
+        sys.exit(1)
+    r = os.system("git bisect good " + state["good"])
+    if r != 0:
+        click.secho("git bisect good failed", fg="red")
+        sys.exit(1)
+    # result = subprocess.run(['ls', '-l'], stdout=subprocess.PIPE)
+    cmd = ["git", "bisect", "bad", state["bad"]]
+    commitid = git_exec_getcommit(cmd)
+    os.chdir(olddir)
+    return commitid
+
+
+def bisection_loop(state):
+    olddir = os.getcwd()
+    os.chdir(state["workdir"])
+    commit = state["next_commit"]
+    if commit is None:
+        click.secho("Bisection error?", fg="green")
+        return
+    click.secho("Testing commit: " + commit, fg="green")
+    cmd = [
+        "kci-dev",
+        "checkout",
+        "--giturl",
+        state["giturl"],
+        "--branch",
+        state["branch"],
+        "--test",
+        state["test"],
+        "--commit",
+        commit,
+        "--watch",
+    ]
+    # jobfilter is array, so we need to add each element as a separate argument
+    for job in state["jobfilter"]:
+        cmd.append("--jobfilter")
+        cmd.append(job)
+    for platform in state["platformfilter"]:
+        cmd.append("--platformfilter")
+        cmd.append(platform)
+    result = kcidev_exec(cmd)
+    try:
+        testret = result.returncode
+    except Exception as e:
+        click.secho(f"Error executing kci-dev, no returncode: {e}", fg="red")
+        sys.exit
+    if testret == 0:
+        bisect_result = "good"
+    elif testret == 1:
+        # TBD: Retry failed test to make sure it is not a flaky test
+        bisect_result = "bad"
+    elif testret == 2:
+        # TBD: Retry failed test to make sure it is not a flaky test
+        bisect_result = "skip"
+    else:
+        click.secho("Maestro failed to execute the test", fg="red")
+        # Internal maestro error, retry procesure
+        return None
+    cmd = ["git", "bisect", bisect_result]
+    commitid = git_exec_getcommit(cmd)
+    if not commitid:
+        click.secho("git bisect failed, commit return is empty", fg="red")
+        sys.exit(1)
+    state["history"].append({commit: bisect_result})
+    state["next_commit"] = commitid
+    os.chdir(olddir)
+    return state
+
+
+@click.command(help="Bisect Linux Kernel regression")
+@click.option("--giturl", help="define the repository url")
+@click.option("--branch", help="define the repository branch")
+@click.option("--good", help="known good commit")
+@click.option("--bad", help="known bad commit")
+@click.option("--retryfail", help="retry failed test N times", default=2)
+@click.option("--workdir", help="define the repository origin", default="kcidev-src")
+@click.option("--ignorestate", help="ignore save state", is_flag=True)
+@click.option("--statefile", help="state file", default="state.json")
+@click.option("--jobfilter", help="filter the job", multiple=True)
+@click.option("--platformfilter", help="filter the platform", multiple=True)
+@click.option("--test", help="Test expected to fail")
+
+# test
+@click.pass_context
+def bisect(
+    ctx,
+    giturl,
+    branch,
+    good,
+    bad,
+    retryfail,
+    workdir,
+    ignorestate,
+    statefile,
+    jobfilter,
+    platformfilter,
+    test,
+):
+    config = ctx.obj.get("CFG")
+    instance = ctx.obj.get("INSTANCE")
+    p_url = api_connection(config[instance]["pipeline"])
+
+    state_file = os.path.join(workdir, statefile)
+    state = load_state(state_file)
+    if state is None or ignorestate:
+        state = default_state
+        if not giturl:
+            click.secho("--giturl is required", fg="red")
+            return
+        if not branch:
+            click.secho("--branch is required", fg="red")
+            return
+        if not good:
+            click.secho("--good is required", fg="red")
+            return
+        if not bad:
+            click.secho("--bad is required", fg="red")
+            return
+        if not jobfilter:
+            click.secho("--jobfilter is required", fg="red")
+            return
+        if not platformfilter:
+            click.secho("--platformfilter is required", fg="red")
+            return
+        if not test:
+            click.secho("--test is required", fg="red")
+            return
+
+        state["giturl"] = giturl
+        state["branch"] = branch
+        state["good"] = good
+        state["bad"] = bad
+        state["retryfail"] = retryfail
+        state["jobfilter"] = jobfilter
+        state["platformfilter"] = platformfilter
+        state["test"] = test
+        state["workdir"] = workdir
+        save_state(state, state_file)
+    else:
+        print_state(state)
+
+    # if workdir doesnt exist, clone the repository
+    if not os.path.exists(workdir):
+        click.secho("Cloning repository", fg="green")
+        repo = Repo.clone_from(giturl, workdir)
+        repo.git.checkout(branch)
+    else:
+        click.secho("Pulling repository", fg="green")
+        repo = Repo(workdir)
+        repo.git.checkout(branch)
+        repo.git.pull()
+
+    if not state["bisect_init"]:
+        state["next_commit"] = init_bisect(state)
+        state["bisect_init"] = True
+        save_state(state, state_file)
+
+    while True:
+        click.secho("Bisection loop", fg="green")
+        new_state = bisection_loop(state)
+        if new_state is None:
+            click.secho("Retry failed test", fg="green")
+            continue
+        state = new_state
+        save_state(state, state_file)
+
+
+if __name__ == "__main__":
+    main_kcidev()