iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

perf/x86/intel: Allocate space for storing LBR stack

Browse Source 
When the LBR call stack is enabled, it is necessary to save/restore
the LBR stack on context switch. We can use pmu specific data to
store LBR stack when task is scheduled out. This patch adds code
that allocates the pmu specific data.

Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Signed-off-by: Kan Liang <kan.liang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Stephane Eranian <eranian@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: jolsa@redhat.com
Link: http://lkml.kernel.org/r/1415156173-10035-8-git-send-email-kan.liang@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit is contained in:
Yan, Zheng 2014-11-04 21:56:03 -05:00 committed by Ingo Molnar
parent 5a158c3ccd
commit e18bf52642
2 changed files with 11 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
arch/x86/kernel/cpu/perf_event.c
View File

@ -432,6 +432,9 @@ int x86_pmu_hw_config(struct perf_event *event)
} }
} }
if (event->attr.branch_sample_type & PERF_SAMPLE_BRANCH_CALL_STACK)
event->attach_state |= PERF_ATTACH_TASK_DATA;
/* /*
* Generate PMC IRQs: * Generate PMC IRQs:
* (keep 'enabled' bit clear for now) * (keep 'enabled' bit clear for now)
@ -1950,6 +1953,7 @@ static struct pmu pmu = {
.event_idx = x86_pmu_event_idx, .event_idx = x86_pmu_event_idx,
.sched_task = x86_pmu_sched_task, .sched_task = x86_pmu_sched_task,
.task_ctx_size = sizeof(struct x86_perf_task_context),
}; };
void arch_perf_update_userpage(struct perf_event *event, void arch_perf_update_userpage(struct perf_event *event,

7
arch/x86/kernel/cpu/perf_event.h
View File

@ -516,6 +516,13 @@ struct x86_pmu {
struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr); struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr);
}; };
struct x86_perf_task_context {
u64 lbr_from[MAX_LBR_ENTRIES];
u64 lbr_to[MAX_LBR_ENTRIES];
int lbr_callstack_users;
int lbr_stack_state;
};
enum { enum {
PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT = PERF_SAMPLE_BRANCH_MAX_SHIFT, PERF_SAMPLE_BRANCH_CALL_STACK_SHIFT = PERF_SAMPLE_BRANCH_MAX_SHIFT,
PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE, PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE,