diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-16 17:06:21 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2019-09-16 17:06:21 -0700 |
commit | 772c1d06bd402f7ee72c61a18c2db74cd74b6758 (patch) | |
tree | e362fc7e158b3580d810a26189ecf91ec8a4f141 /arch/x86/events/intel/pt.c | |
parent | c7eba51cfdf9cd1ca7ed4201b30be8b2bef15ff5 (diff) | |
parent | e336b4027775cb458dc713745e526fa1a1996b2a (diff) | |
download | blackbird-op-linux-772c1d06bd402f7ee72c61a18c2db74cd74b6758.tar.gz blackbird-op-linux-772c1d06bd402f7ee72c61a18c2db74cd74b6758.zip |
Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Ingo Molnar:
"Kernel side changes:
- Improved kbprobes robustness
- Intel PEBS support for PT hardware tracing
- Other Intel PT improvements: high order pages memory footprint
reduction and various related cleanups
- Misc cleanups
The perf tooling side has been very busy in this cycle, with over 300
commits. This is an incomplete high-level summary of the many
improvements done by over 30 developers:
- Lots of updates to the following tools:
'perf c2c'
'perf config'
'perf record'
'perf report'
'perf script'
'perf test'
'perf top'
'perf trace'
- Updates to libperf and libtraceevent, and a consolidation of the
proliferation of x86 instruction decoder libraries.
- Vendor event updates for Intel and PowerPC CPUs,
- Updates to hardware tracing tooling for ARM and Intel CPUs,
- ... and lots of other changes and cleanups - see the shortlog and
Git log for details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (322 commits)
kprobes: Prohibit probing on BUG() and WARN() address
perf/x86: Make more stuff static
x86, perf: Fix the dependency of the x86 insn decoder selftest
objtool: Ignore intentional differences for the x86 insn decoder
objtool: Update sync-check.sh from perf's check-headers.sh
perf build: Ignore intentional differences for the x86 insn decoder
perf intel-pt: Use shared x86 insn decoder
perf intel-pt: Remove inat.c from build dependency list
perf: Update .gitignore file
objtool: Move x86 insn decoder to a common location
perf metricgroup: Support multiple events for metricgroup
perf metricgroup: Scale the metric result
perf pmu: Change convert_scale from static to global
perf symbols: Move mem_info and branch_info out of symbol.h
perf auxtrace: Uninline functions that touch perf_session
perf tools: Remove needless evlist.h include directives
perf tools: Remove needless evlist.h include directives
perf tools: Remove needless thread_map.h include directives
perf tools: Remove needless thread.h include directives
perf tools: Remove needless map.h include directives
...
Diffstat (limited to 'arch/x86/events/intel/pt.c')
-rw-r--r-- | arch/x86/events/intel/pt.c | 330 |
1 files changed, 209 insertions, 121 deletions
diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index d3dc2274ddd4..b1bb4d28e0be 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -545,33 +545,62 @@ static void pt_config_buffer(void *buf, unsigned int topa_idx, wrmsrl(MSR_IA32_RTIT_OUTPUT_MASK, reg); } -/* - * Keep ToPA table-related metadata on the same page as the actual table, - * taking up a few words from the top - */ - -#define TENTS_PER_PAGE (((PAGE_SIZE - 40) / sizeof(struct topa_entry)) - 1) - /** - * struct topa - page-sized ToPA table with metadata at the top - * @table: actual ToPA table entries, as understood by PT hardware + * struct topa - ToPA metadata * @list: linkage to struct pt_buffer's list of tables - * @phys: physical address of this page * @offset: offset of the first entry in this table in the buffer * @size: total size of all entries in this table * @last: index of the last initialized entry in this table + * @z_count: how many times the first entry repeats */ struct topa { - struct topa_entry table[TENTS_PER_PAGE]; struct list_head list; - u64 phys; u64 offset; size_t size; int last; + unsigned int z_count; }; +/* + * Keep ToPA table-related metadata on the same page as the actual table, + * taking up a few words from the top + */ + +#define TENTS_PER_PAGE \ + ((PAGE_SIZE - sizeof(struct topa)) / sizeof(struct topa_entry)) + +/** + * struct topa_page - page-sized ToPA table with metadata at the top + * @table: actual ToPA table entries, as understood by PT hardware + * @topa: metadata + */ +struct topa_page { + struct topa_entry table[TENTS_PER_PAGE]; + struct topa topa; +}; + +static inline struct topa_page *topa_to_page(struct topa *topa) +{ + return container_of(topa, struct topa_page, topa); +} + +static inline struct topa_page *topa_entry_to_page(struct topa_entry *te) +{ + return (struct topa_page *)((unsigned long)te & PAGE_MASK); +} + +static inline phys_addr_t topa_pfn(struct topa *topa) +{ + return PFN_DOWN(virt_to_phys(topa_to_page(topa))); +} + /* make -1 stand for the last table entry */ -#define TOPA_ENTRY(t, i) ((i) == -1 ? &(t)->table[(t)->last] : &(t)->table[(i)]) +#define TOPA_ENTRY(t, i) \ + ((i) == -1 \ + ? &topa_to_page(t)->table[(t)->last] \ + : &topa_to_page(t)->table[(i)]) +#define TOPA_ENTRY_SIZE(t, i) (sizes(TOPA_ENTRY((t), (i))->size)) +#define TOPA_ENTRY_PAGES(t, i) (1 << TOPA_ENTRY((t), (i))->size) /** * topa_alloc() - allocate page-sized ToPA table @@ -583,27 +612,26 @@ struct topa { static struct topa *topa_alloc(int cpu, gfp_t gfp) { int node = cpu_to_node(cpu); - struct topa *topa; + struct topa_page *tp; struct page *p; p = alloc_pages_node(node, gfp | __GFP_ZERO, 0); if (!p) return NULL; - topa = page_address(p); - topa->last = 0; - topa->phys = page_to_phys(p); + tp = page_address(p); + tp->topa.last = 0; /* * In case of singe-entry ToPA, always put the self-referencing END * link as the 2nd entry in the table */ if (!intel_pt_validate_hw_cap(PT_CAP_topa_multiple_entries)) { - TOPA_ENTRY(topa, 1)->base = topa->phys >> TOPA_SHIFT; - TOPA_ENTRY(topa, 1)->end = 1; + TOPA_ENTRY(&tp->topa, 1)->base = page_to_phys(p); + TOPA_ENTRY(&tp->topa, 1)->end = 1; } - return topa; + return &tp->topa; } /** @@ -643,7 +671,7 @@ static void topa_insert_table(struct pt_buffer *buf, struct topa *topa) BUG_ON(last->last != TENTS_PER_PAGE - 1); - TOPA_ENTRY(last, -1)->base = topa->phys >> TOPA_SHIFT; + TOPA_ENTRY(last, -1)->base = topa_pfn(topa); TOPA_ENTRY(last, -1)->end = 1; } @@ -670,7 +698,7 @@ static bool topa_table_full(struct topa *topa) * * Return: 0 on success or error code. */ -static int topa_insert_pages(struct pt_buffer *buf, gfp_t gfp) +static int topa_insert_pages(struct pt_buffer *buf, int cpu, gfp_t gfp) { struct topa *topa = buf->last; int order = 0; @@ -681,13 +709,18 @@ static int topa_insert_pages(struct pt_buffer *buf, gfp_t gfp) order = page_private(p); if (topa_table_full(topa)) { - topa = topa_alloc(buf->cpu, gfp); + topa = topa_alloc(cpu, gfp); if (!topa) return -ENOMEM; topa_insert_table(buf, topa); } + if (topa->z_count == topa->last - 1) { + if (order == TOPA_ENTRY(topa, topa->last - 1)->size) + topa->z_count++; + } + TOPA_ENTRY(topa, -1)->base = page_to_phys(p) >> TOPA_SHIFT; TOPA_ENTRY(topa, -1)->size = order; if (!buf->snapshot && @@ -713,23 +746,26 @@ static void pt_topa_dump(struct pt_buffer *buf) struct topa *topa; list_for_each_entry(topa, &buf->tables, list) { + struct topa_page *tp = topa_to_page(topa); int i; - pr_debug("# table @%p (%016Lx), off %llx size %zx\n", topa->table, - topa->phys, topa->offset, topa->size); + pr_debug("# table @%p, off %llx size %zx\n", tp->table, + topa->offset, topa->size); for (i = 0; i < TENTS_PER_PAGE; i++) { pr_debug("# entry @%p (%lx sz %u %c%c%c) raw=%16llx\n", - &topa->table[i], - (unsigned long)topa->table[i].base << TOPA_SHIFT, - sizes(topa->table[i].size), - topa->table[i].end ? 'E' : ' ', - topa->table[i].intr ? 'I' : ' ', - topa->table[i].stop ? 'S' : ' ', - *(u64 *)&topa->table[i]); + &tp->table[i], + (unsigned long)tp->table[i].base << TOPA_SHIFT, + sizes(tp->table[i].size), + tp->table[i].end ? 'E' : ' ', + tp->table[i].intr ? 'I' : ' ', + tp->table[i].stop ? 'S' : ' ', + *(u64 *)&tp->table[i]); if ((intel_pt_validate_hw_cap(PT_CAP_topa_multiple_entries) && - topa->table[i].stop) || - topa->table[i].end) + tp->table[i].stop) || + tp->table[i].end) break; + if (!i && topa->z_count) + i += topa->z_count; } } } @@ -771,7 +807,7 @@ static void pt_update_head(struct pt *pt) /* offset of the current output region within this table */ for (topa_idx = 0; topa_idx < buf->cur_idx; topa_idx++) - base += sizes(buf->cur->table[topa_idx].size); + base += TOPA_ENTRY_SIZE(buf->cur, topa_idx); if (buf->snapshot) { local_set(&buf->data_size, base); @@ -791,7 +827,7 @@ static void pt_update_head(struct pt *pt) */ static void *pt_buffer_region(struct pt_buffer *buf) { - return phys_to_virt(buf->cur->table[buf->cur_idx].base << TOPA_SHIFT); + return phys_to_virt(TOPA_ENTRY(buf->cur, buf->cur_idx)->base << TOPA_SHIFT); } /** @@ -800,7 +836,7 @@ static void *pt_buffer_region(struct pt_buffer *buf) */ static size_t pt_buffer_region_size(struct pt_buffer *buf) { - return sizes(buf->cur->table[buf->cur_idx].size); + return TOPA_ENTRY_SIZE(buf->cur, buf->cur_idx); } /** @@ -830,7 +866,7 @@ static void pt_handle_status(struct pt *pt) * know. */ if (!intel_pt_validate_hw_cap(PT_CAP_topa_multiple_entries) || - buf->output_off == sizes(TOPA_ENTRY(buf->cur, buf->cur_idx)->size)) { + buf->output_off == pt_buffer_region_size(buf)) { perf_aux_output_flag(&pt->handle, PERF_AUX_FLAG_TRUNCATED); advance++; @@ -868,9 +904,11 @@ static void pt_handle_status(struct pt *pt) static void pt_read_offset(struct pt_buffer *buf) { u64 offset, base_topa; + struct topa_page *tp; rdmsrl(MSR_IA32_RTIT_OUTPUT_BASE, base_topa); - buf->cur = phys_to_virt(base_topa); + tp = phys_to_virt(base_topa); + buf->cur = &tp->topa; rdmsrl(MSR_IA32_RTIT_OUTPUT_MASK, offset); /* offset within current output region */ @@ -879,29 +917,97 @@ static void pt_read_offset(struct pt_buffer *buf) buf->cur_idx = (offset & 0xffffff80) >> 7; } -/** - * pt_topa_next_entry() - obtain index of the first page in the next ToPA entry - * @buf: PT buffer. - * @pg: Page offset in the buffer. - * - * When advancing to the next output region (ToPA entry), given a page offset - * into the buffer, we need to find the offset of the first page in the next - * region. - */ -static unsigned int pt_topa_next_entry(struct pt_buffer *buf, unsigned int pg) +static struct topa_entry * +pt_topa_entry_for_page(struct pt_buffer *buf, unsigned int pg) { - struct topa_entry *te = buf->topa_index[pg]; + struct topa_page *tp; + struct topa *topa; + unsigned int idx, cur_pg = 0, z_pg = 0, start_idx = 0; - /* one region */ - if (buf->first == buf->last && buf->first->last == 1) - return pg; + /* + * Indicates a bug in the caller. + */ + if (WARN_ON_ONCE(pg >= buf->nr_pages)) + return NULL; + + /* + * First, find the ToPA table where @pg fits. With high + * order allocations, there shouldn't be many of these. + */ + list_for_each_entry(topa, &buf->tables, list) { + if (topa->offset + topa->size > pg << PAGE_SHIFT) + goto found; + } + + /* + * Hitting this means we have a problem in the ToPA + * allocation code. + */ + WARN_ON_ONCE(1); - do { - pg++; - pg &= buf->nr_pages - 1; - } while (buf->topa_index[pg] == te); + return NULL; - return pg; +found: + /* + * Indicates a problem in the ToPA allocation code. + */ + if (WARN_ON_ONCE(topa->last == -1)) + return NULL; + + tp = topa_to_page(topa); + cur_pg = PFN_DOWN(topa->offset); + if (topa->z_count) { + z_pg = TOPA_ENTRY_PAGES(topa, 0) * (topa->z_count + 1); + start_idx = topa->z_count + 1; + } + + /* + * Multiple entries at the beginning of the table have the same size, + * ideally all of them; if @pg falls there, the search is done. + */ + if (pg >= cur_pg && pg < cur_pg + z_pg) { + idx = (pg - cur_pg) / TOPA_ENTRY_PAGES(topa, 0); + return &tp->table[idx]; + } + + /* + * Otherwise, slow path: iterate through the remaining entries. + */ + for (idx = start_idx, cur_pg += z_pg; idx < topa->last; idx++) { + if (cur_pg + TOPA_ENTRY_PAGES(topa, idx) > pg) + return &tp->table[idx]; + + cur_pg += TOPA_ENTRY_PAGES(topa, idx); + } + + /* + * Means we couldn't find a ToPA entry in the table that does match. + */ + WARN_ON_ONCE(1); + + return NULL; +} + +static struct topa_entry * +pt_topa_prev_entry(struct pt_buffer *buf, struct topa_entry *te) +{ + unsigned long table = (unsigned long)te & ~(PAGE_SIZE - 1); + struct topa_page *tp; + struct topa *topa; + + tp = (struct topa_page *)table; + if (tp->table != te) + return --te; + + topa = &tp->topa; + if (topa == buf->first) + topa = buf->last; + else + topa = list_prev_entry(topa, list); + + tp = topa_to_page(topa); + + return &tp->table[topa->last - 1]; } /** @@ -925,8 +1031,7 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, unsigned long idx, npages, wakeup; /* can't stop in the middle of an output region */ - if (buf->output_off + handle->size + 1 < - sizes(TOPA_ENTRY(buf->cur, buf->cur_idx)->size)) { + if (buf->output_off + handle->size + 1 < pt_buffer_region_size(buf)) { perf_aux_output_flag(handle, PERF_AUX_FLAG_TRUNCATED); return -EINVAL; } @@ -937,9 +1042,13 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, return 0; /* clear STOP and INT from current entry */ - buf->topa_index[buf->stop_pos]->stop = 0; - buf->topa_index[buf->stop_pos]->intr = 0; - buf->topa_index[buf->intr_pos]->intr = 0; + if (buf->stop_te) { + buf->stop_te->stop = 0; + buf->stop_te->intr = 0; + } + + if (buf->intr_te) + buf->intr_te->intr = 0; /* how many pages till the STOP marker */ npages = handle->size >> PAGE_SHIFT; @@ -950,7 +1059,12 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, idx = (head >> PAGE_SHIFT) + npages; idx &= buf->nr_pages - 1; - buf->stop_pos = idx; + + if (idx != buf->stop_pos) { + buf->stop_pos = idx; + buf->stop_te = pt_topa_entry_for_page(buf, idx); + buf->stop_te = pt_topa_prev_entry(buf, buf->stop_te); + } wakeup = handle->wakeup >> PAGE_SHIFT; @@ -960,51 +1074,20 @@ static int pt_buffer_reset_markers(struct pt_buffer *buf, idx = wakeup; idx &= buf->nr_pages - 1; - buf->intr_pos = idx; + if (idx != buf->intr_pos) { + buf->intr_pos = idx; + buf->intr_te = pt_topa_entry_for_page(buf, idx); + buf->intr_te = pt_topa_prev_entry(buf, buf->intr_te); + } - buf->topa_index[buf->stop_pos]->stop = 1; - buf->topa_index[buf->stop_pos]->intr = 1; - buf->topa_index[buf->intr_pos]->intr = 1; + buf->stop_te->stop = 1; + buf->stop_te->intr = 1; + buf->intr_te->intr = 1; return 0; } /** - * pt_buffer_setup_topa_index() - build topa_index[] table of regions - * @buf: PT buffer. - * - * topa_index[] references output regions indexed by offset into the - * buffer for purposes of quick reverse lookup. - */ -static void pt_buffer_setup_topa_index(struct pt_buffer *buf) -{ - struct topa *cur = buf->first, *prev = buf->last; - struct topa_entry *te_cur = TOPA_ENTRY(cur, 0), - *te_prev = TOPA_ENTRY(prev, prev->last - 1); - int pg = 0, idx = 0; - - while (pg < buf->nr_pages) { - int tidx; - - /* pages within one topa entry */ - for (tidx = 0; tidx < 1 << te_cur->size; tidx++, pg++) - buf->topa_index[pg] = te_prev; - - te_prev = te_cur; - - if (idx == cur->last - 1) { - /* advance to next topa table */ - idx = 0; - cur = list_entry(cur->list.next, struct topa, list); - } else { - idx++; - } - te_cur = TOPA_ENTRY(cur, idx); - } - -} - -/** * pt_buffer_reset_offsets() - adjust buffer's write pointers from aux_head * @buf: PT buffer. * @head: Write pointer (aux_head) from AUX buffer. @@ -1021,18 +1104,20 @@ static void pt_buffer_setup_topa_index(struct pt_buffer *buf) */ static void pt_buffer_reset_offsets(struct pt_buffer *buf, unsigned long head) { + struct topa_page *cur_tp; + struct topa_entry *te; int pg; if (buf->snapshot) head &= (buf->nr_pages << PAGE_SHIFT) - 1; pg = (head >> PAGE_SHIFT) & (buf->nr_pages - 1); - pg = pt_topa_next_entry(buf, pg); + te = pt_topa_entry_for_page(buf, pg); - buf->cur = (struct topa *)((unsigned long)buf->topa_index[pg] & PAGE_MASK); - buf->cur_idx = ((unsigned long)buf->topa_index[pg] - - (unsigned long)buf->cur) / sizeof(struct topa_entry); - buf->output_off = head & (sizes(buf->cur->table[buf->cur_idx].size) - 1); + cur_tp = topa_entry_to_page(te); + buf->cur = &cur_tp->topa; + buf->cur_idx = te - TOPA_ENTRY(buf->cur, 0); + buf->output_off = head & (pt_buffer_region_size(buf) - 1); local64_set(&buf->head, head); local_set(&buf->data_size, 0); @@ -1061,31 +1146,29 @@ static void pt_buffer_fini_topa(struct pt_buffer *buf) * @size: Total size of all regions within this ToPA. * @gfp: Allocation flags. */ -static int pt_buffer_init_topa(struct pt_buffer *buf, unsigned long nr_pages, - gfp_t gfp) +static int pt_buffer_init_topa(struct pt_buffer *buf, int cpu, + unsigned long nr_pages, gfp_t gfp) { struct topa *topa; int err; - topa = topa_alloc(buf->cpu, gfp); + topa = topa_alloc(cpu, gfp); if (!topa) return -ENOMEM; topa_insert_table(buf, topa); while (buf->nr_pages < nr_pages) { - err = topa_insert_pages(buf, gfp); + err = topa_insert_pages(buf, cpu, gfp); if (err) { pt_buffer_fini_topa(buf); return -ENOMEM; } } - pt_buffer_setup_topa_index(buf); - /* link last table to the first one, unless we're double buffering */ if (intel_pt_validate_hw_cap(PT_CAP_topa_multiple_entries)) { - TOPA_ENTRY(buf->last, -1)->base = buf->first->phys >> TOPA_SHIFT; + TOPA_ENTRY(buf->last, -1)->base = topa_pfn(buf->first); TOPA_ENTRY(buf->last, -1)->end = 1; } @@ -1119,18 +1202,18 @@ pt_buffer_setup_aux(struct perf_event *event, void **pages, cpu = raw_smp_processor_id(); node = cpu_to_node(cpu); - buf = kzalloc_node(offsetof(struct pt_buffer, topa_index[nr_pages]), - GFP_KERNEL, node); + buf = kzalloc_node(sizeof(struct pt_buffer), GFP_KERNEL, node); if (!buf) return NULL; - buf->cpu = cpu; buf->snapshot = snapshot; buf->data_pages = pages; + buf->stop_pos = -1; + buf->intr_pos = -1; INIT_LIST_HEAD(&buf->tables); - ret = pt_buffer_init_topa(buf, nr_pages, GFP_KERNEL); + ret = pt_buffer_init_topa(buf, cpu, nr_pages, GFP_KERNEL); if (ret) { kfree(buf); return NULL; @@ -1296,7 +1379,7 @@ void intel_pt_interrupt(void) return; } - pt_config_buffer(buf->cur->table, buf->cur_idx, + pt_config_buffer(topa_to_page(buf->cur)->table, buf->cur_idx, buf->output_off); pt_config(event); } @@ -1361,7 +1444,7 @@ static void pt_event_start(struct perf_event *event, int mode) WRITE_ONCE(pt->handle_nmi, 1); hwc->state = 0; - pt_config_buffer(buf->cur->table, buf->cur_idx, + pt_config_buffer(topa_to_page(buf->cur)->table, buf->cur_idx, buf->output_off); pt_config(event); @@ -1481,6 +1564,11 @@ void cpu_emergency_stop_pt(void) pt_event_stop(pt->handle.event, PERF_EF_UPDATE); } +int is_intel_pt_event(struct perf_event *event) +{ + return event->pmu == &pt_pmu.pmu; +} + static __init int pt_init(void) { int ret, cpu, prior_warn = 0; |