From c6f781e50e75fc2e6b819291b6c5ce6c212f018b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Hyman=20Huang=28=E9=BB=84=E5=8B=87=29?= Date: Sun, 26 Jun 2022 01:38:30 +0800 Subject: [PATCH 1/3] accel/kvm/kvm-all: Refactor per-vcpu dirty ring reaping MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a non-required argument 'CPUState' to kvm_dirty_ring_reap so that it can cover single vcpu dirty-ring-reaping scenario. Signed-off-by: Hyman Huang(黄勇) Reviewed-by: Peter Xu Message-Id: Signed-off-by: Dr. David Alan Gilbert --- accel/kvm/kvm-all.c | 23 +++++++++++++---------- 1 file changed, 13 insertions(+), 10 deletions(-) diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c index f2ce5cd45a2..3bc6eb62945 100644 --- a/accel/kvm/kvm-all.c +++ b/accel/kvm/kvm-all.c @@ -773,17 +773,20 @@ static uint32_t kvm_dirty_ring_reap_one(KVMState *s, CPUState *cpu) } /* Must be with slots_lock held */ -static uint64_t kvm_dirty_ring_reap_locked(KVMState *s) +static uint64_t kvm_dirty_ring_reap_locked(KVMState *s, CPUState* cpu) { int ret; - CPUState *cpu; uint64_t total = 0; int64_t stamp; stamp = get_clock(); - CPU_FOREACH(cpu) { - total += kvm_dirty_ring_reap_one(s, cpu); + if (cpu) { + total = kvm_dirty_ring_reap_one(s, cpu); + } else { + CPU_FOREACH(cpu) { + total += kvm_dirty_ring_reap_one(s, cpu); + } } if (total) { @@ -804,7 +807,7 @@ static uint64_t kvm_dirty_ring_reap_locked(KVMState *s) * Currently for simplicity, we must hold BQL before calling this. We can * consider to drop the BQL if we're clear with all the race conditions. */ -static uint64_t kvm_dirty_ring_reap(KVMState *s) +static uint64_t kvm_dirty_ring_reap(KVMState *s, CPUState *cpu) { uint64_t total; @@ -824,7 +827,7 @@ static uint64_t kvm_dirty_ring_reap(KVMState *s) * reset below. */ kvm_slots_lock(); - total = kvm_dirty_ring_reap_locked(s); + total = kvm_dirty_ring_reap_locked(s, cpu); kvm_slots_unlock(); return total; @@ -871,7 +874,7 @@ static void kvm_dirty_ring_flush(void) * vcpus out in a synchronous way. */ kvm_cpu_synchronize_kick_all(); - kvm_dirty_ring_reap(kvm_state); + kvm_dirty_ring_reap(kvm_state, NULL); trace_kvm_dirty_ring_flush(1); } @@ -1415,7 +1418,7 @@ static void kvm_set_phys_mem(KVMMemoryListener *kml, * Not easy. Let's cross the fingers until it's fixed. */ if (kvm_state->kvm_dirty_ring_size) { - kvm_dirty_ring_reap_locked(kvm_state); + kvm_dirty_ring_reap_locked(kvm_state, NULL); } else { kvm_slot_get_dirty_log(kvm_state, mem); } @@ -1487,7 +1490,7 @@ static void *kvm_dirty_ring_reaper_thread(void *data) r->reaper_state = KVM_DIRTY_RING_REAPER_REAPING; qemu_mutex_lock_iothread(); - kvm_dirty_ring_reap(s); + kvm_dirty_ring_reap(s, NULL); qemu_mutex_unlock_iothread(); r->reaper_iteration++; @@ -2957,7 +2960,7 @@ int kvm_cpu_exec(CPUState *cpu) */ trace_kvm_dirty_ring_full(cpu->cpu_index); qemu_mutex_lock_iothread(); - kvm_dirty_ring_reap(kvm_state); + kvm_dirty_ring_reap(kvm_state, NULL); qemu_mutex_unlock_iothread(); ret = 0; break; -- Gitee From 6e057dd5df580f0e525d808f5476ee973280371d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Hyman=20Huang=28=E9=BB=84=E5=8B=87=29?= Date: Sun, 26 Jun 2022 01:38:31 +0800 Subject: [PATCH 2/3] cpus: Introduce cpu_list_generation_id MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Introduce cpu_list_generation_id to track cpu list generation so that cpu hotplug/unplug can be detected during measurement of dirty page rate. cpu_list_generation_id could be used to detect changes of cpu list, which is prepared for dirty page rate measurement. Signed-off-by: Hyman Huang(黄勇) Reviewed-by: Peter Xu Message-Id: <06e1f1362b2501a471dce796abb065b04f320fa5.1656177590.git.huangy81@chinatelecom.cn> Signed-off-by: Dr. David Alan Gilbert --- cpus-common.c | 8 ++++++++ include/exec/cpu-common.h | 1 + 2 files changed, 9 insertions(+) diff --git a/cpus-common.c b/cpus-common.c index 6e73d3e58da..31c6415f37c 100644 --- a/cpus-common.c +++ b/cpus-common.c @@ -73,6 +73,12 @@ static int cpu_get_free_index(void) } CPUTailQ cpus = QTAILQ_HEAD_INITIALIZER(cpus); +static unsigned int cpu_list_generation_id; + +unsigned int cpu_list_generation_id_get(void) +{ + return cpu_list_generation_id; +} void cpu_list_add(CPUState *cpu) { @@ -84,6 +90,7 @@ void cpu_list_add(CPUState *cpu) assert(!cpu_index_auto_assigned); } QTAILQ_INSERT_TAIL_RCU(&cpus, cpu, node); + cpu_list_generation_id++; } void cpu_list_remove(CPUState *cpu) @@ -96,6 +103,7 @@ void cpu_list_remove(CPUState *cpu) QTAILQ_REMOVE_RCU(&cpus, cpu, node); cpu->cpu_index = UNASSIGNED_CPU_INDEX; + cpu_list_generation_id++; } CPUState *qemu_get_cpu(int index) diff --git a/include/exec/cpu-common.h b/include/exec/cpu-common.h index 039d422bf4c..cdee668f20d 100644 --- a/include/exec/cpu-common.h +++ b/include/exec/cpu-common.h @@ -11,6 +11,7 @@ void qemu_init_cpu_list(void); void cpu_list_lock(void); void cpu_list_unlock(void); +unsigned int cpu_list_generation_id_get(void); void tcg_flush_softmmu_tlb(CPUState *cs); -- Gitee From b6d1e022b7bb06faf2dcad3062b7061b59ef68a9 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Hyman=20Huang=28=E9=BB=84=E5=8B=87=29?= Date: Sun, 26 Jun 2022 01:38:32 +0800 Subject: [PATCH 3/3] migration/dirtyrate: Refactor dirty page rate calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit abstract out dirty log change logic into function global_dirty_log_change. abstract out dirty page rate calculation logic via dirty-ring into function vcpu_calculate_dirtyrate. abstract out mathematical dirty page rate calculation into do_calculate_dirtyrate, decouple it from DirtyStat. rename set_sample_page_period to dirty_stat_wait, which is well-understood and will be reused in dirtylimit. handle cpu hotplug/unplug scenario during measurement of dirty page rate. export util functions outside migration. Signed-off-by: Hyman Huang(黄勇) Reviewed-by: Peter Xu Message-Id: <7b6f6f4748d5b3d017b31a0429e630229ae97538.1656177590.git.huangy81@chinatelecom.cn> Signed-off-by: Dr. David Alan Gilbert --- include/sysemu/dirtyrate.h | 28 +++++ migration/dirtyrate.c | 227 +++++++++++++++++++++++-------------- migration/dirtyrate.h | 7 +- 3 files changed, 174 insertions(+), 88 deletions(-) create mode 100644 include/sysemu/dirtyrate.h diff --git a/include/sysemu/dirtyrate.h b/include/sysemu/dirtyrate.h new file mode 100644 index 00000000000..4d3b9a49022 --- /dev/null +++ b/include/sysemu/dirtyrate.h @@ -0,0 +1,28 @@ +/* + * dirty page rate helper functions + * + * Copyright (c) 2022 CHINA TELECOM CO.,LTD. + * + * Authors: + * Hyman Huang(黄勇) + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef QEMU_DIRTYRATE_H +#define QEMU_DIRTYRATE_H + +typedef struct VcpuStat { + int nvcpu; /* number of vcpu */ + DirtyRateVcpu *rates; /* array of dirty rate for each vcpu */ +} VcpuStat; + +int64_t vcpu_calculate_dirtyrate(int64_t calc_time_ms, + VcpuStat *stat, + unsigned int flag, + bool one_shot); + +void global_dirty_log_change(unsigned int flag, + bool start); +#endif diff --git a/migration/dirtyrate.c b/migration/dirtyrate.c index 8043bc79468..c449095fc31 100644 --- a/migration/dirtyrate.c +++ b/migration/dirtyrate.c @@ -46,7 +46,7 @@ static struct DirtyRateStat DirtyStat; static DirtyRateMeasureMode dirtyrate_mode = DIRTY_RATE_MEASURE_MODE_PAGE_SAMPLING; -static int64_t set_sample_page_period(int64_t msec, int64_t initial_time) +static int64_t dirty_stat_wait(int64_t msec, int64_t initial_time) { int64_t current_time; @@ -60,6 +60,132 @@ static int64_t set_sample_page_period(int64_t msec, int64_t initial_time) return msec; } +static inline void record_dirtypages(DirtyPageRecord *dirty_pages, + CPUState *cpu, bool start) +{ + if (start) { + dirty_pages[cpu->cpu_index].start_pages = cpu->dirty_pages; + } else { + dirty_pages[cpu->cpu_index].end_pages = cpu->dirty_pages; + } +} + +static int64_t do_calculate_dirtyrate(DirtyPageRecord dirty_pages, + int64_t calc_time_ms) +{ + uint64_t memory_size_MB; + uint64_t increased_dirty_pages = + dirty_pages.end_pages - dirty_pages.start_pages; + + memory_size_MB = (increased_dirty_pages * TARGET_PAGE_SIZE) >> 20; + + return memory_size_MB * 1000 / calc_time_ms; +} + +void global_dirty_log_change(unsigned int flag, bool start) +{ + qemu_mutex_lock_iothread(); + if (start) { + memory_global_dirty_log_start(flag); + } else { + memory_global_dirty_log_stop(flag); + } + qemu_mutex_unlock_iothread(); +} + +/* + * global_dirty_log_sync + * 1. sync dirty log from kvm + * 2. stop dirty tracking if needed. + */ +static void global_dirty_log_sync(unsigned int flag, bool one_shot) +{ + qemu_mutex_lock_iothread(); + memory_global_dirty_log_sync(); + if (one_shot) { + memory_global_dirty_log_stop(flag); + } + qemu_mutex_unlock_iothread(); +} + +static DirtyPageRecord *vcpu_dirty_stat_alloc(VcpuStat *stat) +{ + CPUState *cpu; + DirtyPageRecord *records; + int nvcpu = 0; + + CPU_FOREACH(cpu) { + nvcpu++; + } + + stat->nvcpu = nvcpu; + stat->rates = g_malloc0(sizeof(DirtyRateVcpu) * nvcpu); + + records = g_malloc0(sizeof(DirtyPageRecord) * nvcpu); + + return records; +} + +static void vcpu_dirty_stat_collect(VcpuStat *stat, + DirtyPageRecord *records, + bool start) +{ + CPUState *cpu; + + CPU_FOREACH(cpu) { + record_dirtypages(records, cpu, start); + } +} + +int64_t vcpu_calculate_dirtyrate(int64_t calc_time_ms, + VcpuStat *stat, + unsigned int flag, + bool one_shot) +{ + DirtyPageRecord *records; + int64_t init_time_ms; + int64_t duration; + int64_t dirtyrate; + int i = 0; + unsigned int gen_id; + +retry: + init_time_ms = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); + + cpu_list_lock(); + gen_id = cpu_list_generation_id_get(); + records = vcpu_dirty_stat_alloc(stat); + vcpu_dirty_stat_collect(stat, records, true); + cpu_list_unlock(); + + duration = dirty_stat_wait(calc_time_ms, init_time_ms); + + global_dirty_log_sync(flag, one_shot); + + cpu_list_lock(); + if (gen_id != cpu_list_generation_id_get()) { + g_free(records); + g_free(stat->rates); + cpu_list_unlock(); + goto retry; + } + vcpu_dirty_stat_collect(stat, records, false); + cpu_list_unlock(); + + for (i = 0; i < stat->nvcpu; i++) { + dirtyrate = do_calculate_dirtyrate(records[i], duration); + + stat->rates[i].id = i; + stat->rates[i].dirty_rate = dirtyrate; + + trace_dirtyrate_do_calculate_vcpu(i, dirtyrate); + } + + g_free(records); + + return duration; +} + static bool is_sample_period_valid(int64_t sec) { if (sec < MIN_FETCH_DIRTYRATE_TIME_SEC || @@ -396,44 +522,6 @@ static bool compare_page_hash_info(struct RamblockDirtyInfo *info, return true; } -static inline void record_dirtypages(DirtyPageRecord *dirty_pages, - CPUState *cpu, bool start) -{ - if (start) { - dirty_pages[cpu->cpu_index].start_pages = cpu->dirty_pages; - } else { - dirty_pages[cpu->cpu_index].end_pages = cpu->dirty_pages; - } -} - -static void dirtyrate_global_dirty_log_start(void) -{ - qemu_mutex_lock_iothread(); - memory_global_dirty_log_start(GLOBAL_DIRTY_DIRTY_RATE); - qemu_mutex_unlock_iothread(); -} - -static void dirtyrate_global_dirty_log_stop(void) -{ - qemu_mutex_lock_iothread(); - memory_global_dirty_log_sync(); - memory_global_dirty_log_stop(GLOBAL_DIRTY_DIRTY_RATE); - qemu_mutex_unlock_iothread(); -} - -static int64_t do_calculate_dirtyrate_vcpu(DirtyPageRecord dirty_pages) -{ - uint64_t memory_size_MB; - int64_t time_s; - uint64_t increased_dirty_pages = - dirty_pages.end_pages - dirty_pages.start_pages; - - memory_size_MB = (increased_dirty_pages * TARGET_PAGE_SIZE) >> 20; - time_s = DirtyStat.calc_time; - - return memory_size_MB / time_s; -} - static inline void record_dirtypages_bitmap(DirtyPageRecord *dirty_pages, bool start) { @@ -444,11 +532,6 @@ static inline void record_dirtypages_bitmap(DirtyPageRecord *dirty_pages, } } -static void do_calculate_dirtyrate_bitmap(DirtyPageRecord dirty_pages) -{ - DirtyStat.dirty_rate = do_calculate_dirtyrate_vcpu(dirty_pages); -} - static inline void dirtyrate_manual_reset_protect(void) { RAMBlock *block = NULL; @@ -492,71 +575,49 @@ static void calculate_dirtyrate_dirty_bitmap(struct DirtyRateConfig config) DirtyStat.start_time = start_time / 1000; msec = config.sample_period_seconds * 1000; - msec = set_sample_page_period(msec, start_time); + msec = dirty_stat_wait(msec, start_time); DirtyStat.calc_time = msec / 1000; /* - * dirtyrate_global_dirty_log_stop do two things. + * do two things. * 1. fetch dirty bitmap from kvm * 2. stop dirty tracking */ - dirtyrate_global_dirty_log_stop(); + global_dirty_log_sync(GLOBAL_DIRTY_DIRTY_RATE, true); record_dirtypages_bitmap(&dirty_pages, false); - do_calculate_dirtyrate_bitmap(dirty_pages); + DirtyStat.dirty_rate = do_calculate_dirtyrate(dirty_pages, msec); } static void calculate_dirtyrate_dirty_ring(struct DirtyRateConfig config) { - CPUState *cpu; - int64_t msec = 0; - int64_t start_time; + int64_t duration; uint64_t dirtyrate = 0; uint64_t dirtyrate_sum = 0; - DirtyPageRecord *dirty_pages; - int nvcpu = 0; int i = 0; - CPU_FOREACH(cpu) { - nvcpu++; - } - - dirty_pages = g_new(DirtyPageRecord, nvcpu); - - DirtyStat.dirty_ring.nvcpu = nvcpu; - DirtyStat.dirty_ring.rates = g_new(DirtyRateVcpu, nvcpu); - - dirtyrate_global_dirty_log_start(); - - CPU_FOREACH(cpu) { - record_dirtypages(dirty_pages, cpu, true); - } - - start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME); - DirtyStat.start_time = start_time / 1000; + /* start log sync */ + global_dirty_log_change(GLOBAL_DIRTY_DIRTY_RATE, true); - msec = config.sample_period_seconds * 1000; - msec = set_sample_page_period(msec, start_time); - DirtyStat.calc_time = msec / 1000; + DirtyStat.start_time = qemu_clock_get_ms(QEMU_CLOCK_REALTIME) / 1000; - dirtyrate_global_dirty_log_stop(); + /* calculate vcpu dirtyrate */ + duration = vcpu_calculate_dirtyrate(config.sample_period_seconds * 1000, + &DirtyStat.dirty_ring, + GLOBAL_DIRTY_DIRTY_RATE, + true); - CPU_FOREACH(cpu) { - record_dirtypages(dirty_pages, cpu, false); - } + DirtyStat.calc_time = duration / 1000; + /* calculate vm dirtyrate */ for (i = 0; i < DirtyStat.dirty_ring.nvcpu; i++) { - dirtyrate = do_calculate_dirtyrate_vcpu(dirty_pages[i]); - trace_dirtyrate_do_calculate_vcpu(i, dirtyrate); - - DirtyStat.dirty_ring.rates[i].id = i; + dirtyrate = DirtyStat.dirty_ring.rates[i].dirty_rate; DirtyStat.dirty_ring.rates[i].dirty_rate = dirtyrate; dirtyrate_sum += dirtyrate; } DirtyStat.dirty_rate = dirtyrate_sum; - g_free(dirty_pages); } static void calculate_dirtyrate_sample_vm(struct DirtyRateConfig config) @@ -574,7 +635,7 @@ static void calculate_dirtyrate_sample_vm(struct DirtyRateConfig config) rcu_read_unlock(); msec = config.sample_period_seconds * 1000; - msec = set_sample_page_period(msec, initial_time); + msec = dirty_stat_wait(msec, initial_time); DirtyStat.start_time = initial_time / 1000; DirtyStat.calc_time = msec / 1000; diff --git a/migration/dirtyrate.h b/migration/dirtyrate.h index 69d4c5b8655..594a5c0bb64 100644 --- a/migration/dirtyrate.h +++ b/migration/dirtyrate.h @@ -13,6 +13,8 @@ #ifndef QEMU_MIGRATION_DIRTYRATE_H #define QEMU_MIGRATION_DIRTYRATE_H +#include "sysemu/dirtyrate.h" + /* * Sample 512 pages per GB as default. */ @@ -65,11 +67,6 @@ typedef struct SampleVMStat { uint64_t total_block_mem_MB; /* size of total sampled pages in MB */ } SampleVMStat; -typedef struct VcpuStat { - int nvcpu; /* number of vcpu */ - DirtyRateVcpu *rates; /* array of dirty rate for each vcpu */ -} VcpuStat; - /* * Store calculation statistics for each measure. */ -- Gitee