[v3] dump: Cleanup and consolidation

[PATCH v3 3/9] dump: Introduce shdr_num to decrease complexity

Posted by Janosch Frank 3 years, 10 months ago

Let's move from a boolean to a int variable which will later enable us
to store the number of sections that are in the dump file.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
---
 dump/dump.c           | 24 ++++++++++++------------
 include/sysemu/dump.h |  2 +-
 2 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/dump/dump.c b/dump/dump.c
index 0e6187c962..cd11dec0f4 100644
--- a/dump/dump.c
+++ b/dump/dump.c
@@ -140,12 +140,12 @@ static void write_elf64_header(DumpState *s, Error **errp)
     elf_header.e_phoff = cpu_to_dump64(s, sizeof(Elf64_Ehdr));
     elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr));
     elf_header.e_phnum = cpu_to_dump16(s, phnum);
-    if (s->have_section) {
+    if (s->shdr_num) {
         uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) * s->phdr_num;
 
         elf_header.e_shoff = cpu_to_dump64(s, shoff);
         elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr));
-        elf_header.e_shnum = cpu_to_dump16(s, 1);
+        elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
     }
 
     ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
@@ -172,12 +172,12 @@ static void write_elf32_header(DumpState *s, Error **errp)
     elf_header.e_phoff = cpu_to_dump32(s, sizeof(Elf32_Ehdr));
     elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr));
     elf_header.e_phnum = cpu_to_dump16(s, phnum);
-    if (s->have_section) {
+    if (s->shdr_num) {
         uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) * s->phdr_num;
 
         elf_header.e_shoff = cpu_to_dump32(s, shoff);
         elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr));
-        elf_header.e_shnum = cpu_to_dump16(s, 1);
+        elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
     }
 
     ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
@@ -556,7 +556,7 @@ static void dump_begin(DumpState *s, Error **errp)
         }
 
         /* write section to vmcore */
-        if (s->have_section) {
+        if (s->shdr_num) {
             write_elf_section(s, 1, errp);
             if (*errp) {
                 return;
@@ -582,7 +582,7 @@ static void dump_begin(DumpState *s, Error **errp)
         }
 
         /* write section to vmcore */
-        if (s->have_section) {
+        if (s->shdr_num) {
             write_elf_section(s, 0, errp);
             if (*errp) {
                 return;
@@ -1793,11 +1793,11 @@ static void dump_init(DumpState *s, int fd, bool has_format,
      */
     s->phdr_num = 1; /* PT_NOTE */
     if (s->list.num < UINT16_MAX - 2) {
+        s->shdr_num = 0;
         s->phdr_num += s->list.num;
-        s->have_section = false;
     } else {
         /* sh_info of section 0 holds the real number of phdrs */
-        s->have_section = true;
+        s->shdr_num = 1;
 
         /* the type of shdr->sh_info is uint32_t, so we should avoid overflow */
         if (s->list.num <= UINT32_MAX - 1) {
@@ -1808,19 +1808,19 @@ static void dump_init(DumpState *s, int fd, bool has_format,
     }
 
     if (s->dump_info.d_class == ELFCLASS64) {
-        if (s->have_section) {
+        if (s->shdr_num) {
             s->memory_offset = sizeof(Elf64_Ehdr) +
                                sizeof(Elf64_Phdr) * s->phdr_num +
-                               sizeof(Elf64_Shdr) + s->note_size;
+                               sizeof(Elf64_Shdr) * s->shdr_num + s->note_size;
         } else {
             s->memory_offset = sizeof(Elf64_Ehdr) +
                                sizeof(Elf64_Phdr) * s->phdr_num + s->note_size;
         }
     } else {
-        if (s->have_section) {
+        if (s->shdr_num) {
             s->memory_offset = sizeof(Elf32_Ehdr) +
                                sizeof(Elf32_Phdr) * s->phdr_num +
-                               sizeof(Elf32_Shdr) + s->note_size;
+                               sizeof(Elf32_Shdr) * s->shdr_num + s->note_size;
         } else {
             s->memory_offset = sizeof(Elf32_Ehdr) +
                                sizeof(Elf32_Phdr) * s->phdr_num + s->note_size;
diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
index b463fc9c02..19458bffbd 100644
--- a/include/sysemu/dump.h
+++ b/include/sysemu/dump.h
@@ -155,7 +155,7 @@ typedef struct DumpState {
     ArchDumpInfo dump_info;
     MemoryMappingList list;
     uint32_t phdr_num;
-    bool have_section;
+    uint32_t shdr_num;
     bool resume;
     bool detached;
     ssize_t note_size;
-- 
2.32.0

Re: [PATCH v3 3/9] dump: Introduce shdr_num to decrease complexity

Posted by Marc-André Lureau 3 years, 10 months ago

On Wed, Mar 30, 2022 at 4:45 PM Janosch Frank <frankja@linux.ibm.com> wrote:

> Let's move from a boolean to a int variable which will later enable us
> to store the number of sections that are in the dump file.
>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
>

Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>


> ---
>  dump/dump.c           | 24 ++++++++++++------------
>  include/sysemu/dump.h |  2 +-
>  2 files changed, 13 insertions(+), 13 deletions(-)
>
> diff --git a/dump/dump.c b/dump/dump.c
> index 0e6187c962..cd11dec0f4 100644
> --- a/dump/dump.c
> +++ b/dump/dump.c
> @@ -140,12 +140,12 @@ static void write_elf64_header(DumpState *s, Error
> **errp)
>      elf_header.e_phoff = cpu_to_dump64(s, sizeof(Elf64_Ehdr));
>      elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf64_Phdr));
>      elf_header.e_phnum = cpu_to_dump16(s, phnum);
> -    if (s->have_section) {
> +    if (s->shdr_num) {
>          uint64_t shoff = sizeof(Elf64_Ehdr) + sizeof(Elf64_Phdr) *
> s->phdr_num;
>
>          elf_header.e_shoff = cpu_to_dump64(s, shoff);
>          elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf64_Shdr));
> -        elf_header.e_shnum = cpu_to_dump16(s, 1);
> +        elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
>      }
>
>      ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
> @@ -172,12 +172,12 @@ static void write_elf32_header(DumpState *s, Error
> **errp)
>      elf_header.e_phoff = cpu_to_dump32(s, sizeof(Elf32_Ehdr));
>      elf_header.e_phentsize = cpu_to_dump16(s, sizeof(Elf32_Phdr));
>      elf_header.e_phnum = cpu_to_dump16(s, phnum);
> -    if (s->have_section) {
> +    if (s->shdr_num) {
>          uint32_t shoff = sizeof(Elf32_Ehdr) + sizeof(Elf32_Phdr) *
> s->phdr_num;
>
>          elf_header.e_shoff = cpu_to_dump32(s, shoff);
>          elf_header.e_shentsize = cpu_to_dump16(s, sizeof(Elf32_Shdr));
> -        elf_header.e_shnum = cpu_to_dump16(s, 1);
> +        elf_header.e_shnum = cpu_to_dump16(s, s->shdr_num);
>      }
>
>      ret = fd_write_vmcore(&elf_header, sizeof(elf_header), s);
> @@ -556,7 +556,7 @@ static void dump_begin(DumpState *s, Error **errp)
>          }
>
>          /* write section to vmcore */
> -        if (s->have_section) {
> +        if (s->shdr_num) {
>              write_elf_section(s, 1, errp);
>              if (*errp) {
>                  return;
> @@ -582,7 +582,7 @@ static void dump_begin(DumpState *s, Error **errp)
>          }
>
>          /* write section to vmcore */
> -        if (s->have_section) {
> +        if (s->shdr_num) {
>              write_elf_section(s, 0, errp);
>              if (*errp) {
>                  return;
> @@ -1793,11 +1793,11 @@ static void dump_init(DumpState *s, int fd, bool
> has_format,
>       */
>      s->phdr_num = 1; /* PT_NOTE */
>      if (s->list.num < UINT16_MAX - 2) {
> +        s->shdr_num = 0;
>          s->phdr_num += s->list.num;
> -        s->have_section = false;
>      } else {
>          /* sh_info of section 0 holds the real number of phdrs */
> -        s->have_section = true;
> +        s->shdr_num = 1;
>
>          /* the type of shdr->sh_info is uint32_t, so we should avoid
> overflow */
>          if (s->list.num <= UINT32_MAX - 1) {
> @@ -1808,19 +1808,19 @@ static void dump_init(DumpState *s, int fd, bool
> has_format,
>      }
>
>      if (s->dump_info.d_class == ELFCLASS64) {
> -        if (s->have_section) {
> +        if (s->shdr_num) {
>              s->memory_offset = sizeof(Elf64_Ehdr) +
>                                 sizeof(Elf64_Phdr) * s->phdr_num +
> -                               sizeof(Elf64_Shdr) + s->note_size;
> +                               sizeof(Elf64_Shdr) * s->shdr_num +
> s->note_size;
>          } else {
>              s->memory_offset = sizeof(Elf64_Ehdr) +
>                                 sizeof(Elf64_Phdr) * s->phdr_num +
> s->note_size;
>          }
>      } else {
> -        if (s->have_section) {
> +        if (s->shdr_num) {
>              s->memory_offset = sizeof(Elf32_Ehdr) +
>                                 sizeof(Elf32_Phdr) * s->phdr_num +
> -                               sizeof(Elf32_Shdr) + s->note_size;
> +                               sizeof(Elf32_Shdr) * s->shdr_num +
> s->note_size;
>          } else {
>              s->memory_offset = sizeof(Elf32_Ehdr) +
>                                 sizeof(Elf32_Phdr) * s->phdr_num +
> s->note_size;
> diff --git a/include/sysemu/dump.h b/include/sysemu/dump.h
> index b463fc9c02..19458bffbd 100644
> --- a/include/sysemu/dump.h
> +++ b/include/sysemu/dump.h
> @@ -155,7 +155,7 @@ typedef struct DumpState {
>      ArchDumpInfo dump_info;
>      MemoryMappingList list;
>      uint32_t phdr_num;
> -    bool have_section;
> +    uint32_t shdr_num;
>      bool resume;
>      bool detached;
>      ssize_t note_size;
> --
> 2.32.0
>
>
>

-- 
Marc-André Lureau

[PATCH v3 1/9] dump: Use ERRP_GUARD()
[PATCH v3 2/9] dump: Remove the sh_info variable
[PATCH v3 3/9] dump: Introduce shdr_num to decrease complexity
[PATCH v3 4/9] dump: Remove the section if when calculating the memory offset
[PATCH v3 5/9] dump: Add more offset variables
[PATCH v3 6/9] dump: Introduce dump_is_64bit() helper function
[PATCH v3 7/9] dump: Consolidate phdr note writes
[PATCH v3 8/9] dump: Cleanup dump_begin write functions
[PATCH v3 9/9] dump: Consolidate elf note function