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qemu/include/exec/plugin-gen.h

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plugin-gen: add module for TCG-related code We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-07 23:33:56 +03:00
/*
* Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
*
* License: GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
* plugin-gen.h - TCG-dependent definitions for generating plugin code
*
* This header should be included only from plugin.c and C files that emit
* TCG code.
*/
#ifndef QEMU_PLUGIN_GEN_H
#define QEMU_PLUGIN_GEN_H
#include "qemu/plugin.h"
#include "tcg/tcg.h"
struct DisasContextBase;
#ifdef CONFIG_PLUGIN
accel/tcg: allow plugin instrumentation to be disable via cflags When icount is enabled and we recompile an MMIO access we end up double counting the instruction execution. To avoid this we introduce the CF_MEMI cflag which only allows memory instrumentation for the next TB (which won't yet have been counted). As this is part of the hashed compile flags we will only execute the generated TB while coming out of a cpu_io_recompile. While we are at it delete the old TODO. We might as well keep the translation handy as it's likely you will repeatedly hit it on each MMIO access. Reported-by: Aaron Lindsay <aaron@os.amperecomputing.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Tested-by: Aaron Lindsay <aaron@os.amperecomputing.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20210213130325.14781-21-alex.bennee@linaro.org>
2021-02-13 16:03:22 +03:00
bool plugin_gen_tb_start(CPUState *cpu, const TranslationBlock *tb, bool supress);
plugin-gen: add module for TCG-related code We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-07 23:33:56 +03:00
void plugin_gen_tb_end(CPUState *cpu);
void plugin_gen_insn_start(CPUState *cpu, const struct DisasContextBase *db);
void plugin_gen_insn_end(void);
void plugin_gen_disable_mem_helpers(void);
void plugin_gen_empty_mem_callback(TCGv addr, uint32_t info);
plugins: try and make plugin_insn_append more ergonomic Currently we make the assumption that the guest frontend loads all op code bytes sequentially. This mostly holds up for regular fixed encodings but some architectures like s390x like to re-read the instruction which causes weirdness to occur. Rather than changing the frontends make the plugin API a little more ergonomic and able to handle the re-read case. Stuff will still get strange if we read ahead of the opcode but so far no front ends have done that and this patch asserts the case so we can catch it early if they do. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20211026102234.3961636-21-alex.bennee@linaro.org>
2021-10-26 13:22:26 +03:00
static inline void plugin_insn_append(abi_ptr pc, const void *from, size_t size)
plugin-gen: add plugin_insn_append By adding it to plugin-gen's header file, we can export is as an inline, since tcg.h is included in the header (we need tcg_ctx). Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: use g_byte_array] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-08 04:53:09 +03:00
{
struct qemu_plugin_insn *insn = tcg_ctx->plugin_insn;
plugins: try and make plugin_insn_append more ergonomic Currently we make the assumption that the guest frontend loads all op code bytes sequentially. This mostly holds up for regular fixed encodings but some architectures like s390x like to re-read the instruction which causes weirdness to occur. Rather than changing the frontends make the plugin API a little more ergonomic and able to handle the re-read case. Stuff will still get strange if we read ahead of the opcode but so far no front ends have done that and this patch asserts the case so we can catch it early if they do. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20211026102234.3961636-21-alex.bennee@linaro.org>
2021-10-26 13:22:26 +03:00
abi_ptr off;
plugin-gen: add plugin_insn_append By adding it to plugin-gen's header file, we can export is as an inline, since tcg.h is included in the header (we need tcg_ctx). Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: use g_byte_array] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-08 04:53:09 +03:00
if (insn == NULL) {
return;
}
plugins: try and make plugin_insn_append more ergonomic Currently we make the assumption that the guest frontend loads all op code bytes sequentially. This mostly holds up for regular fixed encodings but some architectures like s390x like to re-read the instruction which causes weirdness to occur. Rather than changing the frontends make the plugin API a little more ergonomic and able to handle the re-read case. Stuff will still get strange if we read ahead of the opcode but so far no front ends have done that and this patch asserts the case so we can catch it early if they do. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20211026102234.3961636-21-alex.bennee@linaro.org>
2021-10-26 13:22:26 +03:00
off = pc - insn->vaddr;
if (off < insn->data->len) {
g_byte_array_set_size(insn->data, off);
} else if (off > insn->data->len) {
/* we have an unexpected gap */
g_assert_not_reached();
}
plugin-gen: add plugin_insn_append By adding it to plugin-gen's header file, we can export is as an inline, since tcg.h is included in the header (we need tcg_ctx). Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: use g_byte_array] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-08 04:53:09 +03:00
insn->data = g_byte_array_append(insn->data, from, size);
}
plugin-gen: add module for TCG-related code We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-07 23:33:56 +03:00
#else /* !CONFIG_PLUGIN */
static inline
accel/tcg: allow plugin instrumentation to be disable via cflags When icount is enabled and we recompile an MMIO access we end up double counting the instruction execution. To avoid this we introduce the CF_MEMI cflag which only allows memory instrumentation for the next TB (which won't yet have been counted). As this is part of the hashed compile flags we will only execute the generated TB while coming out of a cpu_io_recompile. While we are at it delete the old TODO. We might as well keep the translation handy as it's likely you will repeatedly hit it on each MMIO access. Reported-by: Aaron Lindsay <aaron@os.amperecomputing.com> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Tested-by: Aaron Lindsay <aaron@os.amperecomputing.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20210213130325.14781-21-alex.bennee@linaro.org>
2021-02-13 16:03:22 +03:00
bool plugin_gen_tb_start(CPUState *cpu, const TranslationBlock *tb, bool supress)
plugin-gen: add module for TCG-related code We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-07 23:33:56 +03:00
{
return false;
}
static inline
void plugin_gen_insn_start(CPUState *cpu, const struct DisasContextBase *db)
{ }
static inline void plugin_gen_insn_end(void)
{ }
static inline void plugin_gen_tb_end(CPUState *cpu)
{ }
static inline void plugin_gen_disable_mem_helpers(void)
{ }
static inline void plugin_gen_empty_mem_callback(TCGv addr, uint32_t info)
{ }
plugins: try and make plugin_insn_append more ergonomic Currently we make the assumption that the guest frontend loads all op code bytes sequentially. This mostly holds up for regular fixed encodings but some architectures like s390x like to re-read the instruction which causes weirdness to occur. Rather than changing the frontends make the plugin API a little more ergonomic and able to handle the re-read case. Stuff will still get strange if we read ahead of the opcode but so far no front ends have done that and this patch asserts the case so we can catch it early if they do. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Suggested-by: Richard Henderson <richard.henderson@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Message-Id: <20211026102234.3961636-21-alex.bennee@linaro.org>
2021-10-26 13:22:26 +03:00
static inline void plugin_insn_append(abi_ptr pc, const void *from, size_t size)
plugin-gen: add plugin_insn_append By adding it to plugin-gen's header file, we can export is as an inline, since tcg.h is included in the header (we need tcg_ctx). Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: use g_byte_array] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-08 04:53:09 +03:00
{ }
plugin-gen: add module for TCG-related code We first inject empty instrumentation from translator_loop. After translation, we go through the plugins to see what they want to register for, filling in the empty instrumentation. If if turns out that some instrumentation remains unused, we remove it. This approach supports the following features: - Inlining TCG code for simple operations. Note that we do not export TCG ops to plugins. Instead, we give them a C API to insert inlined ops. So far we only support adding an immediate to a u64, e.g. to count events. - "Direct" callbacks. These are callbacks that do not go via a helper. Instead, the helper is defined at run-time, so that the plugin code is directly called from TCG. This makes direct callbacks as efficient as possible; they are therefore used for very frequent events, e.g. memory callbacks. - Passing the host address to memory callbacks. Most of this is implemented in a later patch though. - Instrumentation of memory accesses performed from helpers. See the corresponding comment, as well as a later patch. Signed-off-by: Emilio G. Cota <cota@braap.org> [AJB: add alloc_tcg_plugin_context, use glib, rm hwaddr] Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-12-07 23:33:56 +03:00
#endif /* CONFIG_PLUGIN */
#endif /* QEMU_PLUGIN_GEN_H */
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