| Message ID | 20230321052337.26553-2-qiuxu.zhuo@intel.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 2b310e064e797a07765afd4b61c61de70d57ac78 |
| Headers | show |
| Series | [v3,1/2] rcu/rcuscale: Move rcu_scale_*() after kfree_scale_cleanup() | expand |
On Tue, 21 Mar 2023, Qiuxu Zhuo wrote: >When running the 'kfree_rcu_test' test case with commands [1] the call >trace [2] was thrown. This was because the kfree_scale_thread thread(s) >still run after unloading rcuscale and torture modules. Fix the call >trace by invoking kfree_scale_cleanup() from rcu_scale_cleanup() when >removing the rcuscale module. > >[1] modprobe rcuscale kfree_rcu_test=1 > // After some time > rmmod rcuscale > rmmod torture > >[2] BUG: unable to handle page fault for address: ffffffffc0601a87 > #PF: supervisor instruction fetch in kernel mode > #PF: error_code(0x0010) - not-present page > PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0 > Oops: 0010 [#1] PREEMPT SMP NOPTI > CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1 > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 > RIP: 0010:0xffffffffc0601a87 > Code: Unable to access opcode bytes at 0xffffffffc0601a5d. > RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297 > RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000 > RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de > RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000 > R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 > R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe > FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > <TASK> > ? kvfree_call_rcu+0xf0/0x3a0 > ? kthread+0xf3/0x120 > ? kthread_complete_and_exit+0x20/0x20 > ? ret_from_fork+0x1f/0x30 > </TASK> > Modules linked in: rfkill sunrpc ... [last unloaded: torture] > CR2: ffffffffc0601a87 > ---[ end trace 0000000000000000 ]--- > >Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") >Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> Reviewed-by: Davidlohr Bueso <dave@stgolabs.net>
On Tue, Mar 21, 2023 at 08:47:51AM -0700, Davidlohr Bueso wrote: > On Tue, 21 Mar 2023, Qiuxu Zhuo wrote: > > > When running the 'kfree_rcu_test' test case with commands [1] the call > > trace [2] was thrown. This was because the kfree_scale_thread thread(s) > > still run after unloading rcuscale and torture modules. Fix the call > > trace by invoking kfree_scale_cleanup() from rcu_scale_cleanup() when > > removing the rcuscale module. > > > > [1] modprobe rcuscale kfree_rcu_test=1 > > // After some time > > rmmod rcuscale > > rmmod torture > > > > [2] BUG: unable to handle page fault for address: ffffffffc0601a87 > > #PF: supervisor instruction fetch in kernel mode > > #PF: error_code(0x0010) - not-present page > > PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0 > > Oops: 0010 [#1] PREEMPT SMP NOPTI > > CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1 > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 > > RIP: 0010:0xffffffffc0601a87 > > Code: Unable to access opcode bytes at 0xffffffffc0601a5d. > > RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297 > > RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000 > > RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de > > RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000 > > R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 > > R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe > > FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000 > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0 > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > Call Trace: > > <TASK> > > ? kvfree_call_rcu+0xf0/0x3a0 > > ? kthread+0xf3/0x120 > > ? kthread_complete_and_exit+0x20/0x20 > > ? ret_from_fork+0x1f/0x30 > > </TASK> > > Modules linked in: rfkill sunrpc ... [last unloaded: torture] > > CR2: ffffffffc0601a87 > > ---[ end trace 0000000000000000 ]--- > > > > Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") > > Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> > > Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> Much better, thank you both! But unfortunately, these patches do not apply cleanly. Qiuxu Zhuo, could you please forward port these to the -rcu "dev" branch [1]? Thanx, Paul [1] https://mirrors.edge.kernel.org/pub/linux/kernel/people/paulmck/rcutodo.html
On Tue, Mar 21, 2023 at 3:24 PM Paul E. McKenney <paulmck@kernel.org> wrote: > > On Tue, Mar 21, 2023 at 08:47:51AM -0700, Davidlohr Bueso wrote: > > On Tue, 21 Mar 2023, Qiuxu Zhuo wrote: > > > > > When running the 'kfree_rcu_test' test case with commands [1] the call > > > trace [2] was thrown. This was because the kfree_scale_thread thread(s) > > > still run after unloading rcuscale and torture modules. Fix the call > > > trace by invoking kfree_scale_cleanup() from rcu_scale_cleanup() when > > > removing the rcuscale module. > > > > > > [1] modprobe rcuscale kfree_rcu_test=1 > > > // After some time > > > rmmod rcuscale > > > rmmod torture > > > > > > [2] BUG: unable to handle page fault for address: ffffffffc0601a87 > > > #PF: supervisor instruction fetch in kernel mode > > > #PF: error_code(0x0010) - not-present page > > > PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0 > > > Oops: 0010 [#1] PREEMPT SMP NOPTI > > > CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1 > > > Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 > > > RIP: 0010:0xffffffffc0601a87 > > > Code: Unable to access opcode bytes at 0xffffffffc0601a5d. > > > RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297 > > > RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000 > > > RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de > > > RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000 > > > R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 > > > R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe > > > FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000 > > > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > > > CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0 > > > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > > > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > > > Call Trace: > > > <TASK> > > > ? kvfree_call_rcu+0xf0/0x3a0 > > > ? kthread+0xf3/0x120 > > > ? kthread_complete_and_exit+0x20/0x20 > > > ? ret_from_fork+0x1f/0x30 > > > </TASK> > > > Modules linked in: rfkill sunrpc ... [last unloaded: torture] > > > CR2: ffffffffc0601a87 > > > ---[ end trace 0000000000000000 ]--- > > > > > > Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") > > > Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> > > > > Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> > > Much better, thank you both! > > But unfortunately, these patches do not apply cleanly. Qiuxu Zhuo, > could you please forward port these to the -rcu "dev" branch [1]? After making it cleanly apply: Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> thanks, - Joel > > Thanx, Paul > > [1] https://mirrors.edge.kernel.org/pub/linux/kernel/people/paulmck/rcutodo.html
> From: Paul E. McKenney <paulmck@kernel.org> > [...] > > > Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") > > > Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> > > > > Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> > > Much better, thank you both! > > But unfortunately, these patches do not apply cleanly. Qiuxu Zhuo, could > you please forward port these to the -rcu "dev" branch [1]? > Hi Paul, OK. I'll be making v4 patches rebased on the top of the -rcu "dev" branch. Thanks for letting me know more about the RCU patch workflow. Also thank you Davidlohr Bueso and Joel for reviewing the patches. - Qiuxu > Thanx, Paul > > [1] > https://mirrors.edge.kernel.org/pub/linux/kernel/people/paulmck/rcutodo. > html
On Tue, Mar 21, 2023 at 9:26 PM Zhuo, Qiuxu <qiuxu.zhuo@intel.com> wrote: > > > From: Paul E. McKenney <paulmck@kernel.org> > > [...] > > > > Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") > > > > Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> > > > > > > Reviewed-by: Davidlohr Bueso <dave@stgolabs.net> > > > > Much better, thank you both! > > > > But unfortunately, these patches do not apply cleanly. Qiuxu Zhuo, could > > you please forward port these to the -rcu "dev" branch [1]? > > > > Hi Paul, > > OK. > I'll be making v4 patches rebased on the top of the -rcu "dev" branch. > Thanks for letting me know more about the RCU patch workflow. > > Also thank you Davidlohr Bueso and Joel for reviewing the patches. You're welcome and thanks for your interactions on the mailing list and RCU interest. :-) - Joel
diff --git a/kernel/rcu/rcuscale.c b/kernel/rcu/rcuscale.c index e99096a4f094..5a000d26f03e 100644 --- a/kernel/rcu/rcuscale.c +++ b/kernel/rcu/rcuscale.c @@ -797,6 +797,11 @@ rcu_scale_cleanup(void) if (gp_exp && gp_async) SCALEOUT_ERRSTRING("No expedited async GPs, so went with async!"); + if (kfree_rcu_test) { + kfree_scale_cleanup(); + return; + } + if (torture_cleanup_begin()) return; if (!cur_ops) {
When running the 'kfree_rcu_test' test case with commands [1] the call trace [2] was thrown. This was because the kfree_scale_thread thread(s) still run after unloading rcuscale and torture modules. Fix the call trace by invoking kfree_scale_cleanup() from rcu_scale_cleanup() when removing the rcuscale module. [1] modprobe rcuscale kfree_rcu_test=1 // After some time rmmod rcuscale rmmod torture [2] BUG: unable to handle page fault for address: ffffffffc0601a87 #PF: supervisor instruction fetch in kernel mode #PF: error_code(0x0010) - not-present page PGD 11de4f067 P4D 11de4f067 PUD 11de51067 PMD 112f4d067 PTE 0 Oops: 0010 [#1] PREEMPT SMP NOPTI CPU: 1 PID: 1798 Comm: kfree_scale_thr Not tainted 6.3.0-rc1-rcu+ #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 0.0.0 02/06/2015 RIP: 0010:0xffffffffc0601a87 Code: Unable to access opcode bytes at 0xffffffffc0601a5d. RSP: 0018:ffffb25bc2e57e18 EFLAGS: 00010297 RAX: 0000000000000000 RBX: ffffffffc061f0b6 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff962fd0de RDI: ffffffff962fd0de RBP: ffffb25bc2e57ea8 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000 R13: 0000000000000000 R14: 000000000000000a R15: 00000000001c1dbe FS: 0000000000000000(0000) GS:ffff921fa2200000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffffffc0601a5d CR3: 000000011de4c006 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> ? kvfree_call_rcu+0xf0/0x3a0 ? kthread+0xf3/0x120 ? kthread_complete_and_exit+0x20/0x20 ? ret_from_fork+0x1f/0x30 </TASK> Modules linked in: rfkill sunrpc ... [last unloaded: torture] CR2: ffffffffc0601a87 ---[ end trace 0000000000000000 ]--- Fixes: e6e78b004fa7 ("rcuperf: Add kfree_rcu() performance Tests") Signed-off-by: Qiuxu Zhuo <qiuxu.zhuo@intel.com> --- v1 -> v2: - Move rcu_scale_cleanup() after kfree_scale_cleanup() to eliminate the declaration of kfree_scale_cleanup(). - Remove the unnecessary step "modprobe torture" from the commit message. - Add the description for why move rcu_scale_cleanup() after kfree_scale_cleanup() to the commit message. v2 -> v3: - Split the single v2 patch into two patches. - Move the commit message description for why move rcu_scale_cleanup() after kfree_scale_cleanup() to Patch 1. kernel/rcu/rcuscale.c | 5 +++++ 1 file changed, 5 insertions(+)