diff options
| author | Tingwei Zhang <tingwei@codeaurora.org> | 2020-10-05 09:13:17 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-10-05 12:43:54 +0200 |
| commit | b8f8534b10b6ee3cec5e49682d7e0c4796cdccea (patch) | |
| tree | f8fac11b8074f33f6dae56ba7fbbc12c8f2923a4 /drivers/hwtracing/stm/ftrace.c | |
| parent | stm class: ftrace: Enable supported trace export flag (diff) | |
| download | linux-b8f8534b10b6ee3cec5e49682d7e0c4796cdccea.tar.xz linux-b8f8534b10b6ee3cec5e49682d7e0c4796cdccea.zip | |
stm class: ftrace: Use different channel accroding to CPU
To avoid mixup of packets from differnt ftrace packets simultaneously,
use different channel for packets from different CPU.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-7-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/hwtracing/stm/ftrace.c')
| -rw-r--r-- | drivers/hwtracing/stm/ftrace.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/hwtracing/stm/ftrace.c b/drivers/hwtracing/stm/ftrace.c index c694a6e692d1..3bb606dfa634 100644 --- a/drivers/hwtracing/stm/ftrace.c +++ b/drivers/hwtracing/stm/ftrace.c @@ -37,8 +37,10 @@ static void notrace stm_ftrace_write(struct trace_export *export, const void *buf, unsigned int len) { struct stm_ftrace *stm = container_of(export, struct stm_ftrace, ftrace); + /* This is called from trace system with preemption disabled */ + unsigned int cpu = smp_processor_id(); - stm_source_write(&stm->data, STM_FTRACE_CHAN, buf, len); + stm_source_write(&stm->data, STM_FTRACE_CHAN + cpu, buf, len); } static int stm_ftrace_link(struct stm_source_data *data) @@ -63,6 +65,7 @@ static int __init stm_ftrace_init(void) { int ret; + stm_ftrace.data.nr_chans = roundup_pow_of_two(num_possible_cpus()); ret = stm_source_register_device(NULL, &stm_ftrace.data); if (ret) pr_err("Failed to register stm_source - ftrace.\n"); |