perf, x86: Extract PEBS/BTS allocation functions (5ee25c87) · Commits · 戴 / test

arch/x86/kernel/cpu/perf_event_intel_ds.c

+56 −34

Original line number	Diff line number	Diff line
		@@ -74,6 +74,32 @@ static void fini_debug_store_on_cpu(int cpu)
		wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA, 0, 0);
		}

		static int alloc_pebs_buffer(int cpu)
		{
		struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
		int max, thresh = 1; /* always use a single PEBS record */
		void *buffer;

		if (!x86_pmu.pebs)
		return 0;

		buffer = kzalloc(PEBS_BUFFER_SIZE, GFP_KERNEL);
		if (unlikely(!buffer))
		return -ENOMEM;

		max = PEBS_BUFFER_SIZE / x86_pmu.pebs_record_size;

		ds->pebs_buffer_base = (u64)(unsigned long)buffer;
		ds->pebs_index = ds->pebs_buffer_base;
		ds->pebs_absolute_maximum = ds->pebs_buffer_base +
		max * x86_pmu.pebs_record_size;

		ds->pebs_interrupt_threshold = ds->pebs_buffer_base +
		thresh * x86_pmu.pebs_record_size;

		return 0;
		}

		static void release_pebs_buffer(int cpu)
		{
		struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
		@@ -85,6 +111,32 @@ static void release_pebs_buffer(int cpu)
		ds->pebs_buffer_base = 0;
		}

		static int alloc_bts_buffer(int cpu)
		{
		struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
		int max, thresh;
		void *buffer;

		if (!x86_pmu.bts)
		return 0;

		buffer = kzalloc(BTS_BUFFER_SIZE, GFP_KERNEL);
		if (unlikely(!buffer))
		return -ENOMEM;

		max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
		thresh = max / 16;

		ds->bts_buffer_base = (u64)(unsigned long)buffer;
		ds->bts_index = ds->bts_buffer_base;
		ds->bts_absolute_maximum = ds->bts_buffer_base +
		max * BTS_RECORD_SIZE;
		ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
		thresh * BTS_RECORD_SIZE;

		return 0;
		}

		static void release_bts_buffer(int cpu)
		{
		struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
		@@ -133,8 +185,6 @@ static int reserve_ds_buffers(void)

		for_each_possible_cpu(cpu) {
		struct debug_store *ds;
		void *buffer;
		int max, thresh;

		err = -ENOMEM;
		ds = kzalloc(sizeof(*ds), GFP_KERNEL);
		@@ -142,40 +192,12 @@ static int reserve_ds_buffers(void)
		break;
		per_cpu(cpu_hw_events, cpu).ds = ds;

		if (x86_pmu.bts) {
		buffer = kzalloc(BTS_BUFFER_SIZE, GFP_KERNEL);
		if (unlikely(!buffer))
		if (alloc_bts_buffer(cpu))
		break;

		max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
		thresh = max / 16;

		ds->bts_buffer_base = (u64)(unsigned long)buffer;
		ds->bts_index = ds->bts_buffer_base;
		ds->bts_absolute_maximum = ds->bts_buffer_base +
		max * BTS_RECORD_SIZE;
		ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
		thresh * BTS_RECORD_SIZE;
		}

		if (x86_pmu.pebs) {
		buffer = kzalloc(PEBS_BUFFER_SIZE, GFP_KERNEL);
		if (unlikely(!buffer))
		if (alloc_pebs_buffer(cpu))
		break;

		max = PEBS_BUFFER_SIZE / x86_pmu.pebs_record_size;

		ds->pebs_buffer_base = (u64)(unsigned long)buffer;
		ds->pebs_index = ds->pebs_buffer_base;
		ds->pebs_absolute_maximum = ds->pebs_buffer_base +
		max * x86_pmu.pebs_record_size;
		/*
		* Always use single record PEBS
		*/
		ds->pebs_interrupt_threshold = ds->pebs_buffer_base +
		x86_pmu.pebs_record_size;
		}

		err = 0;
		}

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