|
Revision tags: v6.15, v6.15-rc7, v6.15-rc6, v6.15-rc5, v6.15-rc4, v6.15-rc3, v6.15-rc2, v6.15-rc1, v6.14, v6.14-rc7, v6.14-rc6, v6.14-rc5, v6.14-rc4, v6.14-rc3, v6.14-rc2, v6.14-rc1, v6.13, v6.13-rc7, v6.13-rc6, v6.13-rc5, v6.13-rc4, v6.13-rc3, v6.13-rc2, v6.13-rc1, v6.12, v6.12-rc7, v6.12-rc6, v6.12-rc5, v6.12-rc4, v6.12-rc3, v6.12-rc2, v6.12-rc1, v6.11, v6.11-rc7, v6.11-rc6, v6.11-rc5, v6.11-rc4, v6.11-rc3, v6.11-rc2, v6.11-rc1, v6.10, v6.10-rc7, v6.10-rc6, v6.10-rc5, v6.10-rc4, v6.10-rc3, v6.10-rc2, v6.10-rc1, v6.9, v6.9-rc7, v6.9-rc6, v6.9-rc5, v6.9-rc4, v6.9-rc3, v6.9-rc2, v6.9-rc1, v6.8, v6.8-rc7, v6.8-rc6, v6.8-rc5, v6.8-rc4, v6.8-rc3, v6.8-rc2, v6.8-rc1, v6.7, v6.7-rc8, v6.7-rc7, v6.7-rc6, v6.7-rc5, v6.7-rc4, v6.7-rc3, v6.7-rc2, v6.7-rc1, v6.6, v6.6-rc7, v6.6-rc6, v6.6-rc5, v6.6-rc4, v6.6-rc3, v6.6-rc2, v6.6-rc1 |
|
| #
d090ec0d |
| 31-Aug-2023 |
Leonardo Bras <[email protected]> |
smp: Change function signatures to use call_single_data_t
call_single_data_t is a size-aligned typedef of struct __call_single_data.
This alignment is desirable in order to have smp_call_function*(
smp: Change function signatures to use call_single_data_t
call_single_data_t is a size-aligned typedef of struct __call_single_data.
This alignment is desirable in order to have smp_call_function*() avoid bouncing an extra cacheline in case of an unaligned csd, given this would hurt performance.
Since the removal of struct request->csd in commit 660e802c76c8 ("blk-mq: use percpu csd to remote complete instead of per-rq csd") there are no current users of smp_call_function*() with unaligned csd.
Change every 'struct __call_single_data' function parameter to 'call_single_data_t', so we have warnings if any new code tries to introduce an smp_call_function*() call with unaligned csd.
Signed-off-by: Leonardo Bras <[email protected]> Reviewed-by: Guo Ren <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> Link: https://lore.kernel.org/r/[email protected]
show more ...
|
|
Revision tags: v6.5, v6.5-rc7, v6.5-rc6, v6.5-rc5, v6.5-rc4, v6.5-rc3, v6.5-rc2, v6.5-rc1, v6.4, v6.4-rc7 |
|
| #
bf5a8c26 |
| 15-Jun-2023 |
Leonardo Bras <[email protected]> |
trace,smp: Add tracepoints for scheduling remotelly called functions
Add a tracepoint for when a CSD is queued to a remote CPU's call_single_queue. This allows finding exactly which CPU queued a giv
trace,smp: Add tracepoints for scheduling remotelly called functions
Add a tracepoint for when a CSD is queued to a remote CPU's call_single_queue. This allows finding exactly which CPU queued a given CSD when looking at a csd_function_{entry,exit} event, and also enables us to accurately measure IPI delivery time with e.g. a synthetic event:
$ echo 'hist:keys=cpu,csd.hex:ts=common_timestamp.usecs' >\ /sys/kernel/tracing/events/smp/csd_queue_cpu/trigger $ echo 'csd_latency unsigned int dst_cpu; unsigned long csd; u64 time' >\ /sys/kernel/tracing/synthetic_events $ echo \ 'hist:keys=common_cpu,csd.hex:'\ 'time=common_timestamp.usecs-$ts:'\ 'onmatch(smp.csd_queue_cpu).trace(csd_latency,common_cpu,csd,$time)' >\ /sys/kernel/tracing/events/smp/csd_function_entry/trigger
$ trace-cmd record -e 'synthetic:csd_latency' hackbench $ trace-cmd report <...>-467 [001] 21.824263: csd_queue_cpu: cpu=0 callsite=try_to_wake_up+0x2ea func=sched_ttwu_pending csd=0xffff8880076148b8 <...>-467 [001] 21.824280: ipi_send_cpu: cpu=0 callsite=try_to_wake_up+0x2ea callback=generic_smp_call_function_single_interrupt+0x0 <...>-489 [000] 21.824299: csd_function_entry: func=sched_ttwu_pending csd=0xffff8880076148b8 <...>-489 [000] 21.824320: csd_latency: dst_cpu=0, csd=18446612682193848504, time=36
Suggested-by: Valentin Schneider <[email protected]> Signed-off-by: Leonardo Bras <[email protected]> Tested-and-reviewed-by: Valentin Schneider <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Link: https://lore.kernel.org/r/[email protected]
show more ...
|
| #
949fa3f1 |
| 15-Jun-2023 |
Leonardo Bras <[email protected]> |
trace,smp: Add tracepoints around remotelly called functions
The recently added ipi_send_{cpu,cpumask} tracepoints allow finding sources of IPIs targeting CPUs running latency-sensitive applications
trace,smp: Add tracepoints around remotelly called functions
The recently added ipi_send_{cpu,cpumask} tracepoints allow finding sources of IPIs targeting CPUs running latency-sensitive applications.
For NOHZ_FULL CPUs, all IPIs are interference, and those tracepoints are sufficient to find them and work on getting rid of them. In some setups however, not *all* IPIs are to be suppressed, but long-running IPI callbacks can still be problematic.
Add a pair of tracepoints to mark the start and end of processing a CSD IPI callback, similar to what exists for softirq, workqueue or timer callbacks.
Signed-off-by: Leonardo Bras <[email protected]> Tested-and-reviewed-by: Valentin Schneider <[email protected]> Signed-off-by: Peter Zijlstra (Intel) <[email protected]> Link: https://lore.kernel.org/r/[email protected]
show more ...
|