diff options
Diffstat (limited to 'tools/rcu')
| -rwxr-xr-x | tools/rcu/extract-stall.sh | 48 | ||||
| -rw-r--r-- | tools/rcu/rcu-cbs.py | 46 | ||||
| -rwxr-xr-x | tools/rcu/rcu-updaters.sh | 50 |
3 files changed, 144 insertions, 0 deletions
diff --git a/tools/rcu/extract-stall.sh b/tools/rcu/extract-stall.sh new file mode 100755 index 000000000..08a39ad44 --- /dev/null +++ b/tools/rcu/extract-stall.sh @@ -0,0 +1,48 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0+ + +usage() { + echo Extract any RCU CPU stall warnings present in specified file. + echo Filter out clocksource lines. Note that preceding-lines excludes the + echo initial line of the stall warning but trailing-lines includes it. + echo + echo Usage: $(basename $0) dmesg-file [ preceding-lines [ trailing-lines ] ] + echo + echo Error: $1 +} + +# Terminate the script, if the argument is missing + +if test -f "$1" && test -r "$1" +then + : +else + usage "Console log file \"$1\" missing or unreadable." + exit 1 +fi + +echo $1 +preceding_lines="${2-3}" +trailing_lines="${3-10}" + +awk -v preceding_lines="$preceding_lines" -v trailing_lines="$trailing_lines" ' +suffix <= 0 { + for (i = preceding_lines; i > 0; i--) + last[i] = last[i - 1]; + last[0] = $0; +} + +suffix > 0 { + print $0; + suffix--; + if (suffix <= 0) + print ""; +} + +suffix <= 0 && /detected stall/ { + for (i = preceding_lines; i >= 0; i--) + if (last[i] != "") + print last[i]; + suffix = trailing_lines; +}' < "$1" | tr -d '\015' | grep -v clocksource + diff --git a/tools/rcu/rcu-cbs.py b/tools/rcu/rcu-cbs.py new file mode 100644 index 000000000..f8b461b9e --- /dev/null +++ b/tools/rcu/rcu-cbs.py @@ -0,0 +1,46 @@ +#!/usr/bin/env drgn +# SPDX-License-Identifier: GPL-2.0+ +# +# Dump out the number of RCU callbacks outstanding. +# +# On older kernels having multiple flavors of RCU, this dumps out the +# number of callbacks for the most heavily used flavor. +# +# Usage: sudo drgn rcu-cbs.py +# +# Copyright (C) 2021 Facebook, Inc. +# +# Authors: Paul E. McKenney <paulmck@kernel.org> + +import sys +import drgn +from drgn import NULL, Object +from drgn.helpers.linux import * + +def get_rdp0(prog): + try: + rdp0 = prog.variable('rcu_preempt_data', 'kernel/rcu/tree.c'); + except LookupError: + rdp0 = NULL; + + if rdp0 == NULL: + try: + rdp0 = prog.variable('rcu_sched_data', + 'kernel/rcu/tree.c'); + except LookupError: + rdp0 = NULL; + + if rdp0 == NULL: + rdp0 = prog.variable('rcu_data', 'kernel/rcu/tree.c'); + return rdp0.address_of_(); + +rdp0 = get_rdp0(prog); + +# Sum up RCU callbacks. +sum = 0; +for cpu in for_each_possible_cpu(prog): + rdp = per_cpu_ptr(rdp0, cpu); + len = rdp.cblist.len.value_(); + # print("CPU " + str(cpu) + " RCU callbacks: " + str(len)); + sum += len; +print("Number of RCU callbacks in flight: " + str(sum)); diff --git a/tools/rcu/rcu-updaters.sh b/tools/rcu/rcu-updaters.sh new file mode 100755 index 000000000..8a5df3f22 --- /dev/null +++ b/tools/rcu/rcu-updaters.sh @@ -0,0 +1,50 @@ +#!/bin/sh +# SPDX-License-Identifier: GPL-2.0+ +# +# Run bpftrace to obtain a histogram of the types of primitives used to +# initiate RCU grace periods. The count associated with rcu_gp_init() +# is the number of normal (non-expedited) grace periods. +# +# Usage: rcu-updaters.sh [ duration-in-seconds ] +# +# Note that not all kernel builds have all of these functions. In those +# that do not, this script will issue a diagnostic for each that is not +# found, but continue normally for the rest of the functions. + +duration=${1} +if test -n "${duration}" +then + exitclause='interval:s:'"${duration}"' { exit(); }' +else + echo 'Hit control-C to end sample and print results.' +fi +bpftrace -e 'kprobe:kvfree_call_rcu, + kprobe:call_rcu, + kprobe:call_rcu_tasks, + kprobe:call_rcu_tasks_trace, + kprobe:call_srcu, + kprobe:rcu_barrier, + kprobe:rcu_barrier_tasks, + kprobe:rcu_barrier_tasks_trace, + kprobe:srcu_barrier, + kprobe:synchronize_rcu, + kprobe:synchronize_rcu_expedited, + kprobe:synchronize_rcu_tasks, + kprobe:synchronize_rcu_tasks_rude, + kprobe:synchronize_rcu_tasks_trace, + kprobe:synchronize_srcu, + kprobe:synchronize_srcu_expedited, + kprobe:get_state_synchronize_rcu, + kprobe:get_state_synchronize_rcu_full, + kprobe:start_poll_synchronize_rcu, + kprobe:start_poll_synchronize_rcu_expedited, + kprobe:start_poll_synchronize_rcu_full, + kprobe:start_poll_synchronize_rcu_expedited_full, + kprobe:poll_state_synchronize_rcu, + kprobe:poll_state_synchronize_rcu_full, + kprobe:cond_synchronize_rcu, + kprobe:cond_synchronize_rcu_full, + kprobe:start_poll_synchronize_srcu, + kprobe:poll_state_synchronize_srcu, + kprobe:rcu_gp_init + { @counts[func] = count(); } '"${exitclause}" |