From cb6c33d4dc09a8fddda1867708956c27615775f4 Mon Sep 17 00:00:00 2001 From: Wenchao Hao Date: Thu, 8 Dec 2022 22:21:30 +0800 Subject: [PATCH] cma: tracing: print alloc result in trace_cma_alloc_finish The result of the allocation attempt is not printed in trace_cma_alloc_finish, but it's important to do it so we can set filters to catch specific errors on allocation or to trigger some operations on specific errors. We have printed the result in log, but the log is conditional and could not be filtered by tracing events. It introduces little overhead to print this result. The result of allocation is named `errorno' in the trace. Link: https://lkml.kernel.org/r/20221208142130.1501195-1-haowenchao@huawei.com Signed-off-by: Wenchao Hao Cc: Masami Hiramatsu (Google) Cc: Steven Rostedt (Google) Signed-off-by: Andrew Morton --- include/trace/events/cma.h | 32 +++++++++++++++++++++++++++++--- mm/cma.c | 2 +- 2 files changed, 30 insertions(+), 4 deletions(-) diff --git a/include/trace/events/cma.h b/include/trace/events/cma.h index 3d708dae1542..ef75ea606ab2 100644 --- a/include/trace/events/cma.h +++ b/include/trace/events/cma.h @@ -91,12 +91,38 @@ TRACE_EVENT(cma_alloc_start, __entry->align) ); -DEFINE_EVENT(cma_alloc_class, cma_alloc_finish, +TRACE_EVENT(cma_alloc_finish, TP_PROTO(const char *name, unsigned long pfn, const struct page *page, - unsigned long count, unsigned int align), + unsigned long count, unsigned int align, int errorno), - TP_ARGS(name, pfn, page, count, align) + TP_ARGS(name, pfn, page, count, align, errorno), + + TP_STRUCT__entry( + __string(name, name) + __field(unsigned long, pfn) + __field(const struct page *, page) + __field(unsigned long, count) + __field(unsigned int, align) + __field(int, errorno) + ), + + TP_fast_assign( + __assign_str(name, name); + __entry->pfn = pfn; + __entry->page = page; + __entry->count = count; + __entry->align = align; + __entry->errorno = errorno; + ), + + TP_printk("name=%s pfn=0x%lx page=%p count=%lu align=%u errorno=%d", + __get_str(name), + __entry->pfn, + __entry->page, + __entry->count, + __entry->align, + __entry->errorno) ); DEFINE_EVENT(cma_alloc_class, cma_alloc_busy_retry, diff --git a/mm/cma.c b/mm/cma.c index 4a978e09547a..a75b17b03b66 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -491,7 +491,7 @@ struct page *cma_alloc(struct cma *cma, unsigned long count, start = bitmap_no + mask + 1; } - trace_cma_alloc_finish(cma->name, pfn, page, count, align); + trace_cma_alloc_finish(cma->name, pfn, page, count, align, ret); /* * CMA can allocate multiple page blocks, which results in different -- 2.11.0