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Fri, 01 Mar 2024 02:22:08 -0800 (PST) Received: from draig (localhost [IPv6:::1]) by draig.lan (Postfix) with ESMTP id 5F82F5F78A; Fri, 1 Mar 2024 10:22:08 +0000 (GMT) From: =?utf-8?Q?Alex_Benn=C3=A9e?= To: Zhao Liu Cc: qemu-devel@nongnu.org, Pierrick Bouvier , Akihiko Odaki , Alexandre Iooss , Mahmoud Mandour , Richard Henderson , Paolo Bonzini Subject: Re: [PULL 26/29] contrib/plugins: extend execlog to track register changes In-Reply-To: (Zhao Liu's message of "Fri, 1 Mar 2024 15:19:51 +0800") References: <20240228115701.1416107-1-alex.bennee@linaro.org> <20240228115701.1416107-27-alex.bennee@linaro.org> User-Agent: mu4e 1.12.0; emacs 29.1 Date: Fri, 01 Mar 2024 10:22:08 +0000 Message-ID: <87msri5k1b.fsf@draig.linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2a00:1450:4864:20::334; envelope-from=alex.bennee@linaro.org; helo=mail-wm1-x334.google.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Zhao Liu writes: > Hi Alex, > > I hit the following warnings (with "./configure --enable-werror"): > > /qemu/contrib/plugins/execlog.c: In function =E2=80=98registers_init=E2= =80=99: > /qemu/contrib/plugins/execlog.c:330:17: warning: =E2=80=98g_pattern_match= _string=E2=80=99 is deprecated: Use 'g_pattern_spec_match_string' instead [= -Wdeprecated-declarations] > 330 | if (g_pattern_match_string(pat, rd->name) || > | ^~ > In file included from /usr/include/glib-2.0/glib.h:65, > from /qemu/contrib/plugins/execlog.c:9: > /usr/include/glib-2.0/glib/gpattern.h:55:15: note: declared here > 55 | gboolean g_pattern_match_string (GPatternSpec *pspec, > | ^~~~~~~~~~~~~~~~~~~~~~ > /qemu/contrib/plugins/execlog.c:331:21: warning: =E2=80=98g_pattern_match= _string=E2=80=99 is deprecated: Use 'g_pattern_spec_match_string' instead [= -Wdeprecated-declarations] > 331 | g_pattern_match_string(pat, rd_lower)) { > | ^~~~~~~~~~~~~~~~~~~~~~ > In file included from /usr/include/glib-2.0/glib.h:65, > from /qemu/contrib/plugins/execlog.c:9: > /usr/include/glib-2.0/glib/gpattern.h:55:15: note: declared here > 55 | gboolean g_pattern_match_string (GPatternSpec *pspec, > | ^~~~~~~~~~~~~~~~~~~~~~ > /qemu/contrib/plugins/execlog.c:339:63: warning: passing argument 2 of = =E2=80=98g_ptr_array_add=E2=80=99 discards =E2=80=98const=E2=80=99 qualifie= r from pointer target type [-Wdiscarded-qualifiers] > 339 | g_ptr_array_add(all_reg_names, > reg->name); Hmm I missed that. Not sure what the neatest solution is in this case - g_ptr_array_new() doesn't have a destroy func so we shouldn't ever attempt to free it. We can manually re-add the const qualifier at the other end for completeness and I guess comment and cast? > | ~~~^~~= ~~~ > In file included from /usr/include/glib-2.0/glib.h:31, > from /qemu/contrib/plugins/execlog.c:9: > /usr/include/glib-2.0/glib/garray.h:192:62: note: expected =E2=80=98gpoin= ter=E2=80=99 {aka =E2=80=98void *=E2=80=99} but argument is of type =E2=80= =98const char *=E2=80=99 > 192 | gpointer data= ); > | ~~~~~~~~~~~~~~~~~~^~~~ > > In addition, I checked my glic version: > > $ldd --version > ldd (Ubuntu GLIBC 2.35-0ubuntu3.5) 2.35 > > I think it's v2.35. Are these three warning reports valid? It's the glib (not glibc) version that matters here. g_pattern_match_string was deprecated in 2.70 when the suggested alternative was added. However our baseline for glib is still: # When bumping glib minimum version, please check also whether to increase # the _WIN32_WINNT setting in osdep.h according to the value from glib glib_req_ver =3D '>=3D2.56.0' glib_pc =3D dependency('glib-2.0', version: glib_req_ver, required: true, method: 'pkg-config') The usual solution for this is to throw in a compat wrapper in glib-compat.h: --8<---------------cut here---------------start------------->8--- modified include/glib-compat.h @@ -105,6 +105,24 @@ static inline gpointer g_memdup2_qemu(gconstpointer me= m, gsize byte_size) } #define g_memdup2(m, s) g_memdup2_qemu(m, s) =20 +/* + * g_pattern_match_string has been deprecated in Glib since 2.70 and + * will complain about it if you try to use it. Fortunately the + * signature of both functions is the same making it easy to work + * around. + */ +static inline +gboolean g_pattern_spec_match_string_qemu(GPatternSpec *pspec, + const gchar *string) +{ +#if GLIB_CHECK_VERSION(2, 70, 0) + return g_pattern_spec_match_string(pspec, string); +#else + return g_pattern_match_string(pspec, string); +#endif +}; +#define g_pattern_spec_match_string(p, s) g_pattern_spec_match_string_qemu= (p, s) + #if defined(G_OS_UNIX) /* * Note: The fallback implementation is not MT-safe, and it returns a copy= of modified contrib/plugins/execlog.c @@ -334,8 +334,8 @@ static void registers_init(int vcpu_index) for (int p =3D 0; p < rmatches->len; p++) { g_autoptr(GPatternSpec) pat =3D g_pattern_spec_new(rmatche= s->pdata[p]); g_autofree gchar *rd_lower =3D g_utf8_strdown(rd->name, -1= ); - if (g_pattern_match_string(pat, rd->name) || - g_pattern_match_string(pat, rd_lower)) { + if (g_pattern_spec_match_string(pat, rd->name) || + g_pattern_spec_match_string(pat, rd_lower)) { Register *reg =3D init_vcpu_register(vcpu_index, rd); g_ptr_array_add(registers, reg); --8<---------------cut here---------------end--------------->8--- but I hesitated to add it for this case as plugins shouldn't assume they have access to QEMU's internals. Maybe the glib-compat.h header could be treated as a special case. > > I also noticed in target/arm/helper.c, there's another > g_pattern_match_string() but I haven't met the warning. Hmm that's weird. I suspect glib suppresses the warnings with: /* Ask for warnings for anything that was marked deprecated in * the defined version, or before. It is a candidate for rewrite. */ #define GLIB_VERSION_MIN_REQUIRED GLIB_VERSION_2_56 > > Regards, > Zhao > > On Wed, Feb 28, 2024 at 11:56:58AM +0000, Alex Benn=C3=A9e wrote: >> Date: Wed, 28 Feb 2024 11:56:58 +0000 >> From: Alex Benn=C3=A9e >> Subject: [PULL 26/29] contrib/plugins: extend execlog to track register >> changes >> X-Mailer: git-send-email 2.39.2 >>=20 >> With the new plugin register API we can now track changes to register >> values. Currently the implementation is fairly dumb which will slow >> down if a large number of register values are being tracked. This >> could be improved by only instrumenting instructions which mention >> registers we are interested in tracking. >>=20 >> Example usage: >>=20 >> ./qemu-aarch64 -D plugin.log -d plugin \ >> -cpu max,sve256=3Don \ >> -plugin contrib/plugins/libexeclog.so,reg=3Dsp,reg=3Dz\* \ >> ./tests/tcg/aarch64-linux-user/sha512-sve >>=20 >> will display in the execlog any changes to the stack pointer (sp) and >> the SVE Z registers. >>=20 >> As testing registers every instruction will be quite a heavy operation >> there is an additional flag which attempts to optimise the register >> tracking by only instrumenting instructions which are likely to change >> its value. This relies on the QEMU disassembler showing up the register >> names in disassembly so is an explicit opt-in. >>=20 >> Reviewed-by: Pierrick Bouvier >> Cc: Akihiko Odaki >> Based-On: <20231025093128.33116-19-akihiko.odaki@daynix.com> >> Signed-off-by: Alex Benn=C3=A9e >> Message-Id: <20240227144335.1196131-27-alex.bennee@linaro.org> >>=20 >> diff --git a/docs/devel/tcg-plugins.rst b/docs/devel/tcg-plugins.rst >> index 81dcd43a612..fa7421279f5 100644 >> --- a/docs/devel/tcg-plugins.rst >> +++ b/docs/devel/tcg-plugins.rst >> @@ -497,6 +497,22 @@ arguments if required:: >> $ qemu-system-arm $(QEMU_ARGS) \ >> -plugin ./contrib/plugins/libexeclog.so,ifilter=3Dst1w,afilter=3D0x= 40001808 -d plugin >>=20=20 >> +This plugin can also dump registers when they change value. Specify the= name of the >> +registers with multiple ``reg`` options. You can also use glob style ma= tching if you wish:: >> + >> + $ qemu-system-arm $(QEMU_ARGS) \ >> + -plugin ./contrib/plugins/libexeclog.so,reg=3D\*_el2,reg=3Dsp -d pl= ugin >> + >> +Be aware that each additional register to check will slow down >> +execution quite considerably. You can optimise the number of register >> +checks done by using the rdisas option. This will only instrument >> +instructions that mention the registers in question in disassembly. >> +This is not foolproof as some instructions implicitly change >> +instructions. You can use the ifilter to catch these cases: >> + >> + $ qemu-system-arm $(QEMU_ARGS) \ >> + -plugin ./contrib/plugins/libexeclog.so,ifilter=3Dmsr,ifilter=3Dblr= ,reg=3Dx30,reg=3D\*_el1,rdisas=3Don >> + >> - contrib/plugins/cache.c >>=20=20 >> Cache modelling plugin that measures the performance of a given L1 cache >> @@ -583,4 +599,3 @@ The following API is generated from the inline docum= entation in >> include the full kernel-doc annotations. >>=20=20 >> .. kernel-doc:: include/qemu/qemu-plugin.h >> - >> diff --git a/contrib/plugins/execlog.c b/contrib/plugins/execlog.c >> index f262e5555eb..a1dfd59ab71 100644 >> --- a/contrib/plugins/execlog.c >> +++ b/contrib/plugins/execlog.c >> @@ -1,7 +1,7 @@ >> /* >> * Copyright (C) 2021, Alexandre Iooss >> * >> - * Log instruction execution with memory access. >> + * Log instruction execution with memory access and register changes >> * >> * License: GNU GPL, version 2 or later. >> * See the COPYING file in the top-level directory. >> @@ -15,29 +15,40 @@ >>=20=20 >> #include >>=20=20 >> +typedef struct { >> + struct qemu_plugin_register *handle; >> + GByteArray *last; >> + GByteArray *new; >> + const char *name; >> +} Register; >> + >> +typedef struct CPU { >> + /* Store last executed instruction on each vCPU as a GString */ >> + GString *last_exec; >> + /* Ptr array of Register */ >> + GPtrArray *registers; >> +} CPU; >> + >> QEMU_PLUGIN_EXPORT int qemu_plugin_version =3D QEMU_PLUGIN_VERSION; >>=20=20 >> -/* Store last executed instruction on each vCPU as a GString */ >> -static GPtrArray *last_exec; >> +static GArray *cpus; >> static GRWLock expand_array_lock; >>=20=20 >> static GPtrArray *imatches; >> static GArray *amatches; >> +static GPtrArray *rmatches; >> +static bool disas_assist; >> +static GMutex add_reg_name_lock; >> +static GPtrArray *all_reg_names; >>=20=20 >> -/* >> - * Expand last_exec array. >> - * >> - * As we could have multiple threads trying to do this we need to >> - * serialise the expansion under a lock. >> - */ >> -static void expand_last_exec(int cpu_index) >> +static CPU *get_cpu(int vcpu_index) >> { >> - g_rw_lock_writer_lock(&expand_array_lock); >> - while (cpu_index >=3D last_exec->len) { >> - GString *s =3D g_string_new(NULL); >> - g_ptr_array_add(last_exec, s); >> - } >> - g_rw_lock_writer_unlock(&expand_array_lock); >> + CPU *c; >> + g_rw_lock_reader_lock(&expand_array_lock); >> + c =3D &g_array_index(cpus, CPU, vcpu_index); >> + g_rw_lock_reader_unlock(&expand_array_lock); >> + >> + return c; >> } >>=20=20 >> /** >> @@ -46,13 +57,10 @@ static void expand_last_exec(int cpu_index) >> static void vcpu_mem(unsigned int cpu_index, qemu_plugin_meminfo_t info, >> uint64_t vaddr, void *udata) >> { >> - GString *s; >> + CPU *c =3D get_cpu(cpu_index); >> + GString *s =3D c->last_exec; >>=20=20 >> /* Find vCPU in array */ >> - g_rw_lock_reader_lock(&expand_array_lock); >> - g_assert(cpu_index < last_exec->len); >> - s =3D g_ptr_array_index(last_exec, cpu_index); >> - g_rw_lock_reader_unlock(&expand_array_lock); >>=20=20 >> /* Indicate type of memory access */ >> if (qemu_plugin_mem_is_store(info)) { >> @@ -73,32 +81,91 @@ static void vcpu_mem(unsigned int cpu_index, qemu_pl= ugin_meminfo_t info, >> } >>=20=20 >> /** >> - * Log instruction execution >> + * Log instruction execution, outputting the last one. >> + * >> + * vcpu_insn_exec() is a copy and paste of vcpu_insn_exec_with_regs() >> + * without the checking of register values when we've attempted to >> + * optimise with disas_assist. >> */ >> -static void vcpu_insn_exec(unsigned int cpu_index, void *udata) >> +static void insn_check_regs(CPU *cpu) >> { >> - GString *s; >> + for (int n =3D 0; n < cpu->registers->len; n++) { >> + Register *reg =3D cpu->registers->pdata[n]; >> + int sz; >>=20=20 >> - /* Find or create vCPU in array */ >> - g_rw_lock_reader_lock(&expand_array_lock); >> - if (cpu_index >=3D last_exec->len) { >> - g_rw_lock_reader_unlock(&expand_array_lock); >> - expand_last_exec(cpu_index); >> - g_rw_lock_reader_lock(&expand_array_lock); >> + g_byte_array_set_size(reg->new, 0); >> + sz =3D qemu_plugin_read_register(reg->handle, reg->new); >> + g_assert(sz =3D=3D reg->last->len); >> + >> + if (memcmp(reg->last->data, reg->new->data, sz)) { >> + GByteArray *temp =3D reg->last; >> + g_string_append_printf(cpu->last_exec, ", %s -> 0x", reg->n= ame); >> + /* TODO: handle BE properly */ >> + for (int i =3D sz; i >=3D 0; i--) { >> + g_string_append_printf(cpu->last_exec, "%02x", >> + reg->new->data[i]); >> + } >> + reg->last =3D reg->new; >> + reg->new =3D temp; >> + } >> + } >> +} >> + >> +/* Log last instruction while checking registers */ >> +static void vcpu_insn_exec_with_regs(unsigned int cpu_index, void *udat= a) >> +{ >> + CPU *cpu =3D get_cpu(cpu_index); >> + >> + /* Print previous instruction in cache */ >> + if (cpu->last_exec->len) { >> + if (cpu->registers) { >> + insn_check_regs(cpu); >> + } >> + >> + qemu_plugin_outs(cpu->last_exec->str); >> + qemu_plugin_outs("\n"); >> + } >> + >> + /* Store new instruction in cache */ >> + /* vcpu_mem will add memory access information to last_exec */ >> + g_string_printf(cpu->last_exec, "%u, ", cpu_index); >> + g_string_append(cpu->last_exec, (char *)udata); >> +} >> + >> +/* Log last instruction while checking registers, ignore next */ >> +static void vcpu_insn_exec_only_regs(unsigned int cpu_index, void *udat= a) >> +{ >> + CPU *cpu =3D get_cpu(cpu_index); >> + >> + /* Print previous instruction in cache */ >> + if (cpu->last_exec->len) { >> + if (cpu->registers) { >> + insn_check_regs(cpu); >> + } >> + >> + qemu_plugin_outs(cpu->last_exec->str); >> + qemu_plugin_outs("\n"); >> } >> - s =3D g_ptr_array_index(last_exec, cpu_index); >> - g_rw_lock_reader_unlock(&expand_array_lock); >> + >> + /* reset */ >> + cpu->last_exec->len =3D 0; >> +} >> + >> +/* Log last instruction without checking regs, setup next */ >> +static void vcpu_insn_exec(unsigned int cpu_index, void *udata) >> +{ >> + CPU *cpu =3D get_cpu(cpu_index); >>=20=20 >> /* Print previous instruction in cache */ >> - if (s->len) { >> - qemu_plugin_outs(s->str); >> + if (cpu->last_exec->len) { >> + qemu_plugin_outs(cpu->last_exec->str); >> qemu_plugin_outs("\n"); >> } >>=20=20 >> /* Store new instruction in cache */ >> /* vcpu_mem will add memory access information to last_exec */ >> - g_string_printf(s, "%u, ", cpu_index); >> - g_string_append(s, (char *)udata); >> + g_string_printf(cpu->last_exec, "%u, ", cpu_index); >> + g_string_append(cpu->last_exec, (char *)udata); >> } >>=20=20 >> /** >> @@ -111,6 +178,8 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struc= t qemu_plugin_tb *tb) >> { >> struct qemu_plugin_insn *insn; >> bool skip =3D (imatches || amatches); >> + bool check_regs_this =3D rmatches; >> + bool check_regs_next =3D false; >>=20=20 >> size_t n =3D qemu_plugin_tb_n_insns(tb); >> for (size_t i =3D 0; i < n; i++) { >> @@ -131,7 +200,8 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struc= t qemu_plugin_tb *tb) >> /* >> * If we are filtering we better check out if we have any >> * hits. The skip "latches" so we can track memory accesses >> - * after the instruction we care about. >> + * after the instruction we care about. Also enable register >> + * checking on the next instruction. >> */ >> if (skip && imatches) { >> int j; >> @@ -139,6 +209,7 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, struc= t qemu_plugin_tb *tb) >> char *m =3D g_ptr_array_index(imatches, j); >> if (g_str_has_prefix(insn_disas, m)) { >> skip =3D false; >> + check_regs_next =3D rmatches; >> } >> } >> } >> @@ -153,8 +224,39 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, stru= ct qemu_plugin_tb *tb) >> } >> } >>=20=20 >> + /* >> + * Check the disassembly to see if a register we care about >> + * will be affected by this instruction. This relies on the >> + * dissembler doing something sensible for the registers we >> + * care about. >> + */ >> + if (disas_assist && rmatches) { >> + check_regs_next =3D false; >> + gchar *args =3D g_strstr_len(insn_disas, -1, " "); >> + for (int n =3D 0; n < all_reg_names->len; n++) { >> + gchar *reg =3D g_ptr_array_index(all_reg_names, n); >> + if (g_strrstr(args, reg)) { >> + check_regs_next =3D true; >> + skip =3D false; >> + } >> + } >> + } >> + >> + /* >> + * We now have 3 choices: >> + * >> + * - Log insn >> + * - Log insn while checking registers >> + * - Don't log this insn but check if last insn changed registe= rs >> + */ >> + >> if (skip) { >> - g_free(insn_disas); >> + if (check_regs_this) { >> + qemu_plugin_register_vcpu_insn_exec_cb(insn, >> + vcpu_insn_exec_o= nly_regs, >> + QEMU_PLUGIN_CB_R= _REGS, >> + NULL); >> + } >> } else { >> uint32_t insn_opcode; >> insn_opcode =3D *((uint32_t *)qemu_plugin_insn_data(insn)); >> @@ -167,30 +269,124 @@ static void vcpu_tb_trans(qemu_plugin_id_t id, st= ruct qemu_plugin_tb *tb) >> QEMU_PLUGIN_MEM_RW, NULL); >>=20=20 >> /* Register callback on instruction */ >> - qemu_plugin_register_vcpu_insn_exec_cb(insn, vcpu_insn_exec, >> - QEMU_PLUGIN_CB_NO_RE= GS, output); >> + if (check_regs_this) { >> + qemu_plugin_register_vcpu_insn_exec_cb( >> + insn, vcpu_insn_exec_with_regs, >> + QEMU_PLUGIN_CB_R_REGS, >> + output); >> + } else { >> + qemu_plugin_register_vcpu_insn_exec_cb( >> + insn, vcpu_insn_exec, >> + QEMU_PLUGIN_CB_NO_REGS, >> + output); >> + } >>=20=20 >> /* reset skip */ >> skip =3D (imatches || amatches); >> } >>=20=20 >> + /* set regs for next */ >> + if (disas_assist && rmatches) { >> + check_regs_this =3D check_regs_next; >> + } >> + >> + g_free(insn_disas); >> } >> } >>=20=20 >> +static Register *init_vcpu_register(qemu_plugin_reg_descriptor *desc) >> +{ >> + Register *reg =3D g_new0(Register, 1); >> + g_autofree gchar *lower =3D g_utf8_strdown(desc->name, -1); >> + int r; >> + >> + reg->handle =3D desc->handle; >> + reg->name =3D g_intern_string(lower); >> + reg->last =3D g_byte_array_new(); >> + reg->new =3D g_byte_array_new(); >> + >> + /* read the initial value */ >> + r =3D qemu_plugin_read_register(reg->handle, reg->last); >> + g_assert(r > 0); >> + return reg; >> +} >> + >> +static GPtrArray *registers_init(int vcpu_index) >> +{ >> + g_autoptr(GPtrArray) registers =3D g_ptr_array_new(); >> + g_autoptr(GArray) reg_list =3D qemu_plugin_get_registers(); >> + >> + if (rmatches && reg_list->len) { >> + /* >> + * Go through each register in the complete list and >> + * see if we want to track it. >> + */ >> + for (int r =3D 0; r < reg_list->len; r++) { >> + qemu_plugin_reg_descriptor *rd =3D &g_array_index( >> + reg_list, qemu_plugin_reg_descriptor, r); >> + for (int p =3D 0; p < rmatches->len; p++) { >> + g_autoptr(GPatternSpec) pat =3D g_pattern_spec_new(rmat= ches->pdata[p]); >> + g_autofree gchar *rd_lower =3D g_utf8_strdown(rd->name,= -1); >> + if (g_pattern_match_string(pat, rd->name) || >> + g_pattern_match_string(pat, rd_lower)) { >> + Register *reg =3D init_vcpu_register(rd); >> + g_ptr_array_add(registers, reg); >> + >> + /* we need a list of regnames at TB translation tim= e */ >> + if (disas_assist) { >> + g_mutex_lock(&add_reg_name_lock); >> + if (!g_ptr_array_find(all_reg_names, reg->name,= NULL)) { >> + g_ptr_array_add(all_reg_names, reg->name); >> + } >> + g_mutex_unlock(&add_reg_name_lock); >> + } >> + } >> + } >> + } >> + } >> + >> + return registers->len ? g_steal_pointer(®isters) : NULL; >> +} >> + >> +/* >> + * Initialise a new vcpu/thread with: >> + * - last_exec tracking data >> + * - list of tracked registers >> + * - initial value of registers >> + * >> + * As we could have multiple threads trying to do this we need to >> + * serialise the expansion under a lock. >> + */ >> +static void vcpu_init(qemu_plugin_id_t id, unsigned int vcpu_index) >> +{ >> + CPU *c; >> + >> + g_rw_lock_writer_lock(&expand_array_lock); >> + if (vcpu_index >=3D cpus->len) { >> + g_array_set_size(cpus, vcpu_index + 1); >> + } >> + g_rw_lock_writer_unlock(&expand_array_lock); >> + >> + c =3D get_cpu(vcpu_index); >> + c->last_exec =3D g_string_new(NULL); >> + c->registers =3D registers_init(vcpu_index); >> +} >> + >> /** >> * On plugin exit, print last instruction in cache >> */ >> static void plugin_exit(qemu_plugin_id_t id, void *p) >> { >> guint i; >> - GString *s; >> - for (i =3D 0; i < last_exec->len; i++) { >> - s =3D g_ptr_array_index(last_exec, i); >> - if (s->str) { >> - qemu_plugin_outs(s->str); >> + g_rw_lock_reader_lock(&expand_array_lock); >> + for (i =3D 0; i < cpus->len; i++) { >> + CPU *c =3D get_cpu(i); >> + if (c->last_exec && c->last_exec->str) { >> + qemu_plugin_outs(c->last_exec->str); >> qemu_plugin_outs("\n"); >> } >> } >> + g_rw_lock_reader_unlock(&expand_array_lock); >> } >>=20=20 >> /* Add a match to the array of matches */ >> @@ -212,6 +408,18 @@ static void parse_vaddr_match(char *match) >> g_array_append_val(amatches, v); >> } >>=20=20 >> +/* >> + * We have to wait until vCPUs are started before we can check the >> + * patterns find anything. >> + */ >> +static void add_regpat(char *regpat) >> +{ >> + if (!rmatches) { >> + rmatches =3D g_ptr_array_new(); >> + } >> + g_ptr_array_add(rmatches, g_strdup(regpat)); >> +} >> + >> /** >> * Install the plugin >> */ >> @@ -223,11 +431,8 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_plu= gin_id_t id, >> * Initialize dynamic array to cache vCPU instruction. In user mode >> * we don't know the size before emulation. >> */ >> - if (info->system_emulation) { >> - last_exec =3D g_ptr_array_sized_new(info->system.max_vcpus); >> - } else { >> - last_exec =3D g_ptr_array_new(); >> - } >> + cpus =3D g_array_sized_new(true, true, sizeof(CPU), >> + info->system_emulation ? info->system.max_= vcpus : 1); >>=20=20 >> for (int i =3D 0; i < argc; i++) { >> char *opt =3D argv[i]; >> @@ -236,13 +441,22 @@ QEMU_PLUGIN_EXPORT int qemu_plugin_install(qemu_pl= ugin_id_t id, >> parse_insn_match(tokens[1]); >> } else if (g_strcmp0(tokens[0], "afilter") =3D=3D 0) { >> parse_vaddr_match(tokens[1]); >> + } else if (g_strcmp0(tokens[0], "reg") =3D=3D 0) { >> + add_regpat(tokens[1]); >> + } else if (g_strcmp0(tokens[0], "rdisas") =3D=3D 0) { >> + if (!qemu_plugin_bool_parse(tokens[0], tokens[1], &disas_as= sist)) { >> + fprintf(stderr, "boolean argument parsing failed: %s\n"= , opt); >> + return -1; >> + } >> + all_reg_names =3D g_ptr_array_new(); >> } else { >> fprintf(stderr, "option parsing failed: %s\n", opt); >> return -1; >> } >> } >>=20=20 >> - /* Register translation block and exit callbacks */ >> + /* Register init, translation block and exit callbacks */ >> + qemu_plugin_register_vcpu_init_cb(id, vcpu_init); >> qemu_plugin_register_vcpu_tb_trans_cb(id, vcpu_tb_trans); >> qemu_plugin_register_atexit_cb(id, plugin_exit, NULL); >>=20=20 >> --=20 >> 2.39.2 >>=20 >>=20 --=20 Alex Benn=C3=A9e Virtualisation Tech Lead @ Linaro