From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konrad Rzeszutek Wilk Subject: Re: [PATCH v2 01/13] Export hypervisor symbols Date: Mon, 23 Sep 2013 15:42:49 -0400 Message-ID: <20130923194249.GA3019@phenom.dumpdata.com> References: <1379670132-1748-1-git-send-email-boris.ostrovsky@oracle.com> <1379670132-1748-2-git-send-email-boris.ostrovsky@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <1379670132-1748-2-git-send-email-boris.ostrovsky@oracle.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Boris Ostrovsky Cc: jun.nakajima@intel.com, George.Dunlap@eu.citrix.com, jacob.shin@amd.com, eddie.dong@intel.com, dietmar.hahn@ts.fujitsu.com, xen-devel@lists.xen.org, JBeulich@suse.com, suravee.suthikulpanit@amd.com List-Id: xen-devel@lists.xenproject.org On Fri, Sep 20, 2013 at 05:42:00AM -0400, Boris Ostrovsky wrote: I think the title needs a prefix of say: "xen/platform_op:" or such. > Export Xen's symbols in format similar to Linux' /proc/kallsyms. Which is? I see in Linux: 000000000000bd58 D xen_cr3 ... 000000000000e978 d soft_lockup_hrtimer_cnt .. ffffffff8101cef0 T eager_fpu_init ffffffff8101d010 t ptrace_triggered I know that the first column is the EIP (thought some of them seem to be based on some offset). The last one is pretty obvious too. But the middle one: konrad@phenom:~$ cat /proc/kallsyms | awk '{print $2}' | sort | uniq b B d D r R t T V W Could you explain what those mean? And are they part of this? Or does Xen not carry those? > > Signed-off-by: Boris Ostrovsky > --- > xen/arch/x86/platform_hypercall.c | 9 +++++ > xen/arch/x86/x86_64/platform_hypercall.c | 2 +- > xen/common/symbols-dummy.c | 1 + > xen/common/symbols.c | 58 ++++++++++++++++++++++++++++++-- > xen/include/public/platform.h | 22 ++++++++++++ > xen/include/xen/symbols.h | 4 +++ > xen/tools/symbols.c | 4 +++ > 7 files changed, 97 insertions(+), 3 deletions(-) > > diff --git a/xen/arch/x86/platform_hypercall.c b/xen/arch/x86/platform_hypercall.c > index 7175a82..39376fe 100644 > --- a/xen/arch/x86/platform_hypercall.c > +++ b/xen/arch/x86/platform_hypercall.c > @@ -23,6 +23,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -597,6 +598,14 @@ ret_t do_platform_op(XEN_GUEST_HANDLE_PARAM(xen_platform_op_t) u_xenpf_op) > } > break; > > + case XENPF_get_symbols: > + { > + ret = xensyms_read(&op->u.symdata); > + if ( ret >= 0 && __copy_field_to_guest(u_xenpf_op, op, u.symdata) ) > + ret = -EFAULT; > + } > + break; > + > default: > ret = -ENOSYS; > break; > diff --git a/xen/arch/x86/x86_64/platform_hypercall.c b/xen/arch/x86/x86_64/platform_hypercall.c > index aa2ad54..9ef705a 100644 > --- a/xen/arch/x86/x86_64/platform_hypercall.c > +++ b/xen/arch/x86/x86_64/platform_hypercall.c > @@ -35,7 +35,7 @@ CHECK_pf_pcpu_version; > #undef xen_pf_pcpu_version > > #define xenpf_enter_acpi_sleep compat_pf_enter_acpi_sleep > - > +#define xenpf_symdata compat_pf_symdata > #define COMPAT > #define _XEN_GUEST_HANDLE(t) XEN_GUEST_HANDLE(t) > #define _XEN_GUEST_HANDLE_PARAM(t) XEN_GUEST_HANDLE_PARAM(t) > diff --git a/xen/common/symbols-dummy.c b/xen/common/symbols-dummy.c > index 5090c3b..52a86c7 100644 > --- a/xen/common/symbols-dummy.c > +++ b/xen/common/symbols-dummy.c > @@ -12,6 +12,7 @@ const unsigned int symbols_offsets[1]; > const unsigned long symbols_addresses[1]; > #endif > const unsigned int symbols_num_syms; > +const unsigned long symbols_names_bytes; > const u8 symbols_names[1]; > > const u8 symbols_token_table[1]; > diff --git a/xen/common/symbols.c b/xen/common/symbols.c > index 83b2b58..e74a585 100644 > --- a/xen/common/symbols.c > +++ b/xen/common/symbols.c > @@ -17,6 +17,8 @@ > #include > #include > #include > +#include > +#include > > #ifdef SYMBOLS_ORIGIN > extern const unsigned int symbols_offsets[1]; > @@ -26,6 +28,7 @@ extern const unsigned long symbols_addresses[]; > #define symbols_address(n) symbols_addresses[n] > #endif > extern const unsigned int symbols_num_syms; > +extern const unsigned long symbols_names_bytes; > extern const u8 symbols_names[]; > > extern const u8 symbols_token_table[]; > @@ -35,7 +38,8 @@ extern const unsigned int symbols_markers[]; > > /* expand a compressed symbol data into the resulting uncompressed string, > given the offset to where the symbol is in the compressed stream */ > -static unsigned int symbols_expand_symbol(unsigned int off, char *result) > +static unsigned int symbols_expand_symbol(unsigned int off, char *result, > + int maxlen) > { > int len, skipped_first = 0; > const u8 *tptr, *data; > @@ -49,6 +53,9 @@ static unsigned int symbols_expand_symbol(unsigned int off, char *result) > * the compressed stream */ > off += len + 1; > > + if (maxlen < len) > + len = maxlen; > + > /* for every byte on the compressed symbol data, copy the table > entry for that byte */ > while(len) { > @@ -129,7 +136,7 @@ const char *symbols_lookup(unsigned long addr, > --low; > > /* Grab name */ > - symbols_expand_symbol(get_symbol_offset(low), namebuf); > + symbols_expand_symbol(get_symbol_offset(low), namebuf, sizeof(namebuf)); > > /* Search for next non-aliased symbol */ > for (i = low + 1; i < symbols_num_syms; i++) { > @@ -174,3 +181,50 @@ void __print_symbol(const char *fmt, unsigned long address) > > spin_unlock_irqrestore(&lock, flags); > } > + > +/* > + * Get symbol type information. This is encoded as a single char at the > + * beginning of the symbol name. > + */ > +static char symbols_get_symbol_type(unsigned int off) > +{ > + /* > + * Get just the first code, look it up in the token table, > + * and return the first char from this token. > + */ > + return symbols_token_table[symbols_token_index[symbols_names[off + 1]]]; > +} > + > +/* > + * Symbols are most likely accessed sequentially so we remember position from > + * previous read. This can help us avoid extra call to get_symbol_offset(). > + */ > +static uint64_t next_symbol, next_offset; > +static DEFINE_SPINLOCK(symbols_mutex); > + > +int xensyms_read(struct xenpf_symdata *symdata) > +{ > + if ( symdata->xen_symnum > symbols_num_syms ) > + return -EINVAL; > + else if ( symdata->xen_symnum == symbols_num_syms ) > + return 0; > + > + spin_lock(&symbols_mutex); > + > + if ( symdata->xen_symnum == 0 ) > + next_offset = next_symbol = 0; > + else if ( next_symbol != symdata->xen_symnum ) > + /* Non-sequential access */ > + next_offset = get_symbol_offset(symdata->xen_symnum); > + > + symdata->type = symbols_get_symbol_type(next_offset); > + next_offset = symbols_expand_symbol(next_offset, symdata->name, > + sizeof(symdata->name)); > + symdata->address = symbols_offsets[symdata->xen_symnum] + SYMBOLS_ORIGIN; > + > + next_symbol = symdata->xen_symnum + 1; > + > + spin_unlock(&symbols_mutex); > + > + return strlen(symdata->name); > +} > diff --git a/xen/include/public/platform.h b/xen/include/public/platform.h > index 4341f54..870e14b 100644 > --- a/xen/include/public/platform.h > +++ b/xen/include/public/platform.h > @@ -527,6 +527,27 @@ struct xenpf_core_parking { > typedef struct xenpf_core_parking xenpf_core_parking_t; > DEFINE_XEN_GUEST_HANDLE(xenpf_core_parking_t); > > +#define XENPF_get_symbols 61 > + > +struct xenpf_symdata { > + /* IN variables */ > + uint64_t xen_symnum; > + > + /* OUT variables */ > + uint64_t address; > + uint64_t type; > + /* > + * KSYM_NAME_LEN is 128 bytes. However, we cannot be larger than pad in > + * xen_platform_op below (which is 128 bytes as well). Since the largest > + * symbol is around 50 bytes it's probably more trouble than it's worth > + * to try to deal with symbols that are close to 128 bytes in length. > + */ > +#define XEN_SYMS_MAX_LEN (128 - 3 * 8) > + char name[XEN_SYMS_MAX_LEN]; > +}; > +typedef struct xenpf_symdata xenpf_symdata_t; > +DEFINE_XEN_GUEST_HANDLE(xenpf_symdata_t); > + > /* > * ` enum neg_errnoval > * ` HYPERVISOR_platform_op(const struct xen_platform_op*); > @@ -553,6 +574,7 @@ struct xen_platform_op { > struct xenpf_cpu_hotadd cpu_add; > struct xenpf_mem_hotadd mem_add; > struct xenpf_core_parking core_parking; > + struct xenpf_symdata symdata; > uint8_t pad[128]; > } u; > }; > diff --git a/xen/include/xen/symbols.h b/xen/include/xen/symbols.h > index 37cf6bf..c8df28f 100644 > --- a/xen/include/xen/symbols.h > +++ b/xen/include/xen/symbols.h > @@ -2,6 +2,8 @@ > #define _XEN_SYMBOLS_H > > #include > +#include > +#include > > #define KSYM_NAME_LEN 127 > > @@ -34,4 +36,6 @@ do { \ > __print_symbol(fmt, addr); \ > } while(0) > > +extern int xensyms_read(struct xenpf_symdata *symdata); > + > #endif /*_XEN_SYMBOLS_H*/ > diff --git a/xen/tools/symbols.c b/xen/tools/symbols.c > index f39c906..818204d 100644 > --- a/xen/tools/symbols.c > +++ b/xen/tools/symbols.c > @@ -272,6 +272,10 @@ static void write_src(void) > } > printf("\n"); > > + output_label("symbols_names_bytes"); > + printf("\t.long\t%d\n", off); > + printf("\n"); > + > output_label("symbols_markers"); > for (i = 0; i < ((table_cnt + 255) >> 8); i++) > printf("\t.long\t%d\n", markers[i]); > -- > 1.8.1.4 > > > _______________________________________________ > Xen-devel mailing list > Xen-devel@lists.xen.org > http://lists.xen.org/xen-devel