[v2,12/27] function_graph: Have the instances use their own ftrace_ops for filtering

Message ID	20240602033833.030750126@goodmis.org (mailing list archive)
State	Not Applicable
Delegated to:	BPF
Headers	show Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7F5BC2E3E9; Sun, 2 Jun 2024 03:37:26 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717299446; cv=none; b=G+G6ivSDpyqyB26Bm8ws/5Sh64XuPryaup/KalwSgpoaakJEshxDJASmz/p8bU/C9GYGFMOmsrF782PnyIaJB423oiq1uzV/GXW6cU+EMGGdD6uxoxFchZM8juF/suxC558gAOwMTDIt2QAfeCb6Xmhoj9TeO0SRQ0RGqfz8Fpc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1717299446; c=relaxed/simple; bh=A0U9sr9GFbpsRBnq39/LgmZBDUIWBAfS7ig9mkIzpvw=; h=Message-ID:Date:From:To:Cc:Subject:References:MIME-Version: Content-Type; b=ogwAqk2ENAEh6kDP4MXQCiWHDOwu+FQwD6ly8cZXQVMOsb8mRB1/JR/1CLKLHDZOJTAiyKNHAvQQNVeiP5Nxg73CtgBMr7x21av8GXs6bWjNf6wBQWH/JFmR6VscCjI3Si4gJypytHRcT9KO7vY1UkyE7s+jHqZLFhAq+Jqi29U= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 Received: by smtp.kernel.org (Postfix) with ESMTPSA id D7C0EC4DDE1; Sun, 2 Jun 2024 03:37:25 +0000 (UTC) Received: from rostedt by gandalf with local (Exim 4.97) (envelope-from <rostedt@goodmis.org>) id 1sDc3F-000000094Ow-0iNP; Sat, 01 Jun 2024 23:38:33 -0400 Message-ID: <20240602033833.030750126@goodmis.org> User-Agent: quilt/0.68 Date: Sat, 01 Jun 2024 23:37:56 -0400 From: Steven Rostedt <rostedt@goodmis.org> To: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org Cc: Masami Hiramatsu <mhiramat@kernel.org>, Mark Rutland <mark.rutland@arm.com>, Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Andrew Morton <akpm@linux-foundation.org>, Alexei Starovoitov <alexei.starovoitov@gmail.com>, Florent Revest <revest@chromium.org>, Martin KaFai Lau <martin.lau@linux.dev>, bpf <bpf@vger.kernel.org>, Sven Schnelle <svens@linux.ibm.com>, Alexei Starovoitov <ast@kernel.org>, Jiri Olsa <jolsa@kernel.org>, Arnaldo Carvalho de Melo <acme@kernel.org>, Daniel Borkmann <daniel@iogearbox.net>, Alan Maguire <alan.maguire@oracle.com>, Peter Zijlstra <peterz@infradead.org>, Thomas Gleixner <tglx@linutronix.de>, Guo Ren <guoren@kernel.org> Subject: [PATCH v2 12/27] function_graph: Have the instances use their own ftrace_ops for filtering References: <20240602033744.563858532@goodmis.org> Precedence: bulk X-Mailing-List: bpf@vger.kernel.org List-Id: <bpf.vger.kernel.org> List-Subscribe: <mailto:bpf+subscribe@vger.kernel.org> List-Unsubscribe: <mailto:bpf+unsubscribe@vger.kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8
Series	function_graph: Allow multiple users for function graph tracing \| expand [v2,00/27] function_graph: Allow multiple users for function graph tracing [v2,01/27] function_graph: Convert ret_stack to a series of longs [v2,02/27] fgraph: Use BUILD_BUG_ON() to make sure we have structures divisible by long [v2,03/27] function_graph: Add an array structure that will allow multiple callbacks [v2,04/27] function_graph: Allow multiple users to attach to function graph [v2,05/27] function_graph: Handle tail calls for stack unwinding [v2,06/27] function_graph: Remove logic around ftrace_graph_entry and return [v2,07/27] ftrace/function_graph: Pass fgraph_ops to function graph callbacks [v2,08/27] ftrace: Allow function_graph tracer to be enabled in instances [v2,09/27] ftrace: Allow ftrace startup flags to exist without dynamic ftrace [v2,10/27] ftrace: Add subops logic to allow one ops to manage many [v2,11/27] ftrace: Allow subops filtering to be modified [v2,12/27] function_graph: Have the instances use their own ftrace_ops for filtering [v2,13/27] function_graph: Add pid tracing back to function graph tracer [v2,14/27] function_graph: Use a simple LRU for fgraph_array index number [v2,15/27] function_graph: Add "task variables" per task for fgraph_ops [v2,16/27] function_graph: Move set_graph_function tests to shadow stack global var [v2,17/27] function_graph: Move graph depth stored data to shadow stack global var [v2,18/27] function_graph: Move graph notrace bit to shadow stack global var [v2,19/27] function_graph: Implement fgraph_reserve_data() and fgraph_retrieve_data() [v2,20/27] function_graph: Add selftest for passing local variables [v2,21/27] ftrace: Add multiple fgraph storage selftest [v2,22/27] function_graph: Use for_each_set_bit() in __ftrace_return_to_handler() [v2,23/27] function_graph: Use bitmask to loop on fgraph entry [v2,24/27] function_graph: Use static_call and branch to optimize entry function [v2,25/27] function_graph: Use static_call and branch to optimize return function [v2,26/27] selftests/ftrace: Add function_graph tracer to func-filter-pid test [v2,27/27] selftests/ftrace: Add fgraph-multi.tc test

Context	Check	Description
netdev/tree_selection	success	Not a local patch

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h index 63238a9a9270..8f865689e868 100644 --- a/include/linux/ftrace.h +++ b/include/linux/ftrace.h @@ -1046,6 +1046,7 @@ extern int ftrace_graph_entry_stub(struct ftrace_graph_ent *trace, struct fgraph struct fgraph_ops { trace_func_graph_ent_t entryfunc; trace_func_graph_ret_t retfunc; + struct ftrace_ops ops; /* for the hash lists */ void *private; int idx; }; diff --git a/kernel/trace/fgraph.c b/kernel/trace/fgraph.c index e39042c40937..3ef6db53c0bf 100644 --- a/kernel/trace/fgraph.c +++ b/kernel/trace/fgraph.c @@ -18,15 +18,6 @@ #include "ftrace_internal.h" #include "trace.h" -#ifdef CONFIG_DYNAMIC_FTRACE -#define ASSIGN_OPS_HASH(opsname, val) \ - .func_hash = val, \ - .local_hash.regex_lock = __MUTEX_INITIALIZER(opsname.local_hash.regex_lock), \ - .subop_list = LIST_HEAD_INIT(opsname.subop_list), -#else -#define ASSIGN_OPS_HASH(opsname, val) -#endif - /* * FGRAPH_FRAME_SIZE: Size in bytes of the meta data on the shadow stack * FGRAPH_FRAME_OFFSET: Size in long words of the meta data frame @@ -156,6 +147,13 @@ get_bitmap_bits(struct task_struct *t, int offset) return (t->ret_stack[offset] >> FGRAPH_INDEX_SHIFT) & FGRAPH_INDEX_MASK; } +/* For BITMAP type: set the bits in the bitmap bitmask at @offset on ret_stack */ +static inline void +set_bitmap_bits(struct task_struct *t, int offset, unsigned long bitmap) +{ + t->ret_stack[offset] |= (bitmap << FGRAPH_INDEX_SHIFT); +} + /* Write the bitmap to the ret_stack at @offset (does index, offset and bitmask) */ static inline void set_bitmap(struct task_struct *t, int offset, unsigned long bitmap) @@ -382,7 +380,8 @@ int function_graph_enter(unsigned long ret, unsigned long func, if (gops == &fgraph_stub) continue; - if (gops->entryfunc(&trace, gops)) + if (ftrace_ops_test(&gops->ops, func, NULL) && + gops->entryfunc(&trace, gops)) bitmap |= BIT(i); } @@ -665,16 +664,28 @@ unsigned long ftrace_graph_ret_addr(struct task_struct *task, int *idx, static struct ftrace_ops graph_ops = { .func = ftrace_graph_func, - .flags = FTRACE_OPS_FL_INITIALIZED | - FTRACE_OPS_FL_PID | - FTRACE_OPS_GRAPH_STUB, + .flags = FTRACE_OPS_GRAPH_STUB, #ifdef FTRACE_GRAPH_TRAMP_ADDR .trampoline = FTRACE_GRAPH_TRAMP_ADDR, /* trampoline_size is only needed for dynamically allocated tramps */ #endif - ASSIGN_OPS_HASH(graph_ops, &global_ops.local_hash) }; +void fgraph_init_ops(struct ftrace_ops *dst_ops, + struct ftrace_ops *src_ops) +{ + dst_ops->flags = FTRACE_OPS_FL_PID | FTRACE_OPS_GRAPH_STUB; + +#ifdef CONFIG_DYNAMIC_FTRACE + if (src_ops) { + dst_ops->func_hash = &src_ops->local_hash; + mutex_init(&dst_ops->local_hash.regex_lock); + INIT_LIST_HEAD(&dst_ops->subop_list); + dst_ops->flags |= FTRACE_OPS_FL_INITIALIZED; + } +#endif +} + void ftrace_graph_sleep_time_control(bool enable) { fgraph_sleep_time = enable; @@ -877,6 +888,7 @@ static int start_graph_tracing(void) int register_ftrace_graph(struct fgraph_ops *gops) { + int command = 0; int ret = 0; int i; @@ -894,7 +906,7 @@ int register_ftrace_graph(struct fgraph_ops *gops) break; } if (i >= FGRAPH_ARRAY_SIZE) { - ret = -EBUSY; + ret = -ENOSPC; goto out; } @@ -908,18 +920,22 @@ int register_ftrace_graph(struct fgraph_ops *gops) if (ftrace_graph_active == 1) { register_pm_notifier(&ftrace_suspend_notifier); ret = start_graph_tracing(); - if (ret) { - ftrace_graph_active--; - goto out; - } + if (ret) + goto error; /* * Some archs just test to see if these are not * the default function */ ftrace_graph_return = return_run; ftrace_graph_entry = entry_run; + command = FTRACE_START_FUNC_RET; + } - ret = ftrace_startup(&graph_ops, FTRACE_START_FUNC_RET); + ret = ftrace_startup_subops(&graph_ops, &gops->ops, command); +error: + if (ret) { + fgraph_array[i] = &fgraph_stub; + ftrace_graph_active--; } out: mutex_unlock(&ftrace_lock); @@ -928,6 +944,7 @@ int register_ftrace_graph(struct fgraph_ops *gops) void unregister_ftrace_graph(struct fgraph_ops *gops) { + int command = 0; int i; mutex_lock(&ftrace_lock); @@ -935,25 +952,29 @@ void unregister_ftrace_graph(struct fgraph_ops *gops) if (unlikely(!ftrace_graph_active)) goto out; - for (i = 0; i < fgraph_array_cnt; i++) - if (gops == fgraph_array[i]) - break; - if (i >= fgraph_array_cnt) + if (unlikely(gops->idx < 0 || gops->idx >= fgraph_array_cnt)) goto out; - fgraph_array[i] = &fgraph_stub; - if (i + 1 == fgraph_array_cnt) { - for (; i >= 0; i--) - if (fgraph_array[i] != &fgraph_stub) - break; + WARN_ON_ONCE(fgraph_array[gops->idx] != gops); + + fgraph_array[gops->idx] = &fgraph_stub; + if (gops->idx + 1 == fgraph_array_cnt) { + i = gops->idx; + while (i >= 0 && fgraph_array[i] == &fgraph_stub) + i--; fgraph_array_cnt = i + 1; } ftrace_graph_active--; + + if (!ftrace_graph_active) + command = FTRACE_STOP_FUNC_RET; + + ftrace_shutdown_subops(&graph_ops, &gops->ops, command); + if (!ftrace_graph_active) { ftrace_graph_return = ftrace_stub_graph; ftrace_graph_entry = ftrace_graph_entry_stub; - ftrace_shutdown(&graph_ops, FTRACE_STOP_FUNC_RET); unregister_pm_notifier(&ftrace_suspend_notifier); unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL); } diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index e447b04c0c9c..3615614bd116 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -7793,7 +7793,7 @@ __init void ftrace_init_global_array_ops(struct trace_array *tr) tr->ops = &global_ops; tr->ops->private = tr; ftrace_init_trace_array(tr); - init_array_fgraph_ops(tr); + init_array_fgraph_ops(tr, tr->ops); } void ftrace_init_array_ops(struct trace_array *tr, ftrace_func_t func) diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 9a70beb2cc46..f06b5ddd3580 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -894,8 +894,8 @@ extern int __trace_graph_entry(struct trace_array *tr, extern void __trace_graph_return(struct trace_array *tr, struct ftrace_graph_ret *trace, unsigned int trace_ctx); -extern void init_array_fgraph_ops(struct trace_array *tr); -extern int allocate_fgraph_ops(struct trace_array *tr); +extern void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops); +extern int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops); extern void free_fgraph_ops(struct trace_array *tr); #ifdef CONFIG_DYNAMIC_FTRACE @@ -1003,18 +1003,19 @@ static inline bool ftrace_graph_ignore_func(struct ftrace_graph_ent *trace) (fgraph_max_depth && trace->depth >= fgraph_max_depth); } +void fgraph_init_ops(struct ftrace_ops *dst_ops, + struct ftrace_ops *src_ops); + #else /* CONFIG_FUNCTION_GRAPH_TRACER */ static inline enum print_line_t print_graph_function_flags(struct trace_iterator *iter, u32 flags) { return TRACE_TYPE_UNHANDLED; } -static inline void init_array_fgraph_ops(struct trace_array *tr) { } -static inline int allocate_fgraph_ops(struct trace_array *tr) -{ - return 0; -} static inline void free_fgraph_ops(struct trace_array *tr) { } +/* ftrace_ops may not be defined */ +#define init_array_fgraph_ops(tr, ops) do { } while (0) +#define allocate_fgraph_ops(tr, ops) ({ 0; }) #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ extern struct list_head ftrace_pids; diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c index 8e8da0d0ee52..13bf2415245d 100644 --- a/kernel/trace/trace_functions.c +++ b/kernel/trace/trace_functions.c @@ -91,7 +91,7 @@ int ftrace_create_function_files(struct trace_array *tr, if (!tr->ops) return -EINVAL; - ret = allocate_fgraph_ops(tr); + ret = allocate_fgraph_ops(tr, tr->ops); if (ret) { kfree(tr->ops); return ret; diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c index 9ccc904a7703..7f30652f0e97 100644 --- a/kernel/trace/trace_functions_graph.c +++ b/kernel/trace/trace_functions_graph.c @@ -288,7 +288,7 @@ static struct fgraph_ops funcgraph_ops = { .retfunc = &trace_graph_return, }; -int allocate_fgraph_ops(struct trace_array *tr) +int allocate_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops) { struct fgraph_ops *gops; @@ -301,6 +301,9 @@ int allocate_fgraph_ops(struct trace_array *tr) tr->gops = gops; gops->private = tr; + + fgraph_init_ops(&gops->ops, ops); + return 0; } @@ -309,10 +312,11 @@ void free_fgraph_ops(struct trace_array *tr) kfree(tr->gops); } -__init void init_array_fgraph_ops(struct trace_array *tr) +__init void init_array_fgraph_ops(struct trace_array *tr, struct ftrace_ops *ops) { tr->gops = &funcgraph_ops; funcgraph_ops.private = tr; + fgraph_init_ops(&tr->gops->ops, ops); } static int graph_trace_init(struct trace_array *tr)

[v2,12/27] function_graph: Have the instances use their own ftrace_ops for filtering

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