From: Yan, Zheng Date: Wed, 5 Nov 2014 02:56:02 +0000 (-0500) Subject: perf: Always switch pmu specific data during context switch X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=5a158c3ccd2183a7b0866be6685d001fe653430f;p=GitHub%2FLineageOS%2FG12%2Fandroid_kernel_amlogic_linux-4.9.git perf: Always switch pmu specific data during context switch If two tasks were both forked from the same parent task, Events in their perf task contexts can be the same. Perf core may leave out switching the perf event contexts. Previous patch inroduces pmu specific data. The data is for saving the LBR stack, it is task specific. So we need to switch the data even when context switch is optimized out. Signed-off-by: Yan, Zheng Signed-off-by: Kan Liang Signed-off-by: Peter Zijlstra (Intel) Cc: Arnaldo Carvalho de Melo Cc: Linus Torvalds Cc: Paul Mackerras Cc: eranian@google.com Cc: jolsa@redhat.com Link: http://lkml.kernel.org/r/1415156173-10035-7-git-send-email-kan.liang@intel.com Signed-off-by: Ingo Molnar --- diff --git a/kernel/events/core.c b/kernel/events/core.c index 688086bb7144..84451c0debba 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -2562,6 +2562,9 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn, next->perf_event_ctxp[ctxn] = ctx; ctx->task = next; next_ctx->task = task; + + swap(ctx->task_ctx_data, next_ctx->task_ctx_data); + do_switch = 0; perf_event_sync_stat(ctx, next_ctx);